// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (interfaces/draft-IERC1822.sol)
pragma solidity ^0.8.0;
/**
 * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
 * proxy whose upgrades are fully controlled by the current implementation.
 */
interface IERC1822Proxiable {
    /**
     * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
     * address.
     *
     * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
     * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
     * function revert if invoked through a proxy.
     */
    function proxiableUUID() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Proxy.sol)
pragma solidity ^0.8.0;
import "../Proxy.sol";
import "./ERC1967Upgrade.sol";
/**
 * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
 * implementation address that can be changed. This address is stored in storage in the location specified by
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
 * implementation behind the proxy.
 */
contract ERC1967Proxy is Proxy, ERC1967Upgrade {
    /**
     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
     *
     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
     * function call, and allows initializating the storage of the proxy like a Solidity constructor.
     */
    constructor(address _logic, bytes memory _data) payable {
        assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
        _upgradeToAndCall(_logic, _data, false);
    }
    /**
     * @dev Returns the current implementation address.
     */
    function _implementation() internal view virtual override returns (address impl) {
        return ERC1967Upgrade._getImplementation();
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/ERC1967/ERC1967Upgrade.sol)
pragma solidity ^0.8.2;
import "../beacon/IBeacon.sol";
import "../../interfaces/draft-IERC1822.sol";
import "../../utils/Address.sol";
import "../../utils/StorageSlot.sol";
/**
 * @dev This abstract contract provides getters and event emitting update functions for
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
 *
 * _Available since v4.1._
 *
 * @custom:oz-upgrades-unsafe-allow delegatecall
 */
abstract contract ERC1967Upgrade {
    // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
    bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
    /**
     * @dev Emitted when the implementation is upgraded.
     */
    event Upgraded(address indexed implementation);
    /**
     * @dev Returns the current implementation address.
     */
    function _getImplementation() internal view returns (address) {
        return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
    }
    /**
     * @dev Stores a new address in the EIP1967 implementation slot.
     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
        StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
    }
    /**
     * @dev Perform implementation upgrade
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }
    /**
     * @dev Perform implementation upgrade with additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCall(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        _upgradeTo(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }
    }
    /**
     * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCallUUPS(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        // Upgrades from old implementations will perform a rollback test. This test requires the new
        // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
        // this special case will break upgrade paths from old UUPS implementation to new ones.
        if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
            _setImplementation(newImplementation);
        } else {
            try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
            } catch {
                revert("ERC1967Upgrade: new implementation is not UUPS");
            }
            _upgradeToAndCall(newImplementation, data, forceCall);
        }
    }
    /**
     * @dev Storage slot with the admin of the contract.
     * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
    /**
     * @dev Emitted when the admin account has changed.
     */
    event AdminChanged(address previousAdmin, address newAdmin);
    /**
     * @dev Returns the current admin.
     */
    function _getAdmin() internal view virtual returns (address) {
        return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
    }
    /**
     * @dev Stores a new address in the EIP1967 admin slot.
     */
    function _setAdmin(address newAdmin) private {
        require(newAdmin != address(0), "ERC1967: new admin is the zero address");
        StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
    }
    /**
     * @dev Changes the admin of the proxy.
     *
     * Emits an {AdminChanged} event.
     */
    function _changeAdmin(address newAdmin) internal {
        emit AdminChanged(_getAdmin(), newAdmin);
        _setAdmin(newAdmin);
    }
    /**
     * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
     * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
     */
    bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
    /**
     * @dev Emitted when the beacon is upgraded.
     */
    event BeaconUpgraded(address indexed beacon);
    /**
     * @dev Returns the current beacon.
     */
    function _getBeacon() internal view returns (address) {
        return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
    }
    /**
     * @dev Stores a new beacon in the EIP1967 beacon slot.
     */
    function _setBeacon(address newBeacon) private {
        require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
        require(Address.isContract(IBeacon(newBeacon).implementation()), "ERC1967: beacon implementation is not a contract");
        StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
    }
    /**
     * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
     * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
     *
     * Emits a {BeaconUpgraded} event.
     */
    function _upgradeBeaconToAndCall(
        address newBeacon,
        bytes memory data,
        bool forceCall
    ) internal {
        _setBeacon(newBeacon);
        emit BeaconUpgraded(newBeacon);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/Proxy.sol)
pragma solidity ^0.8.0;
/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 *
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 *
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     *
     * This function does not return to its internal call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal virtual {
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())
            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())
            switch result
            // delegatecall returns 0 on error.
            case 0 {
                revert(0, returndatasize())
            }
            default {
                return(0, returndatasize())
            }
        }
    }
    /**
     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal view virtual returns (address);
    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     *
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _fallback() internal virtual {
        _beforeFallback();
        _delegate(_implementation());
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback() external payable virtual {
        _fallback();
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive() external payable virtual {
        _fallback();
    }
    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     *
     * If overriden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
pragma solidity ^0.8.0;
/**
 * @dev This is the interface that {BeaconProxy} expects of its beacon.
 */
interface IBeacon {
    /**
     * @dev Must return an address that can be used as a delegate call target.
     *
     * {BeaconProxy} will check that this address is a contract.
     */
    function implementation() external view returns (address);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/transparent/TransparentUpgradeableProxy.sol)
pragma solidity ^0.8.0;
import "../ERC1967/ERC1967Proxy.sol";
/**
 * @dev This contract implements a proxy that is upgradeable by an admin.
 *
 * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
 * clashing], which can potentially be used in an attack, this contract uses the
 * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
 * things that go hand in hand:
 *
 * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
 * that call matches one of the admin functions exposed by the proxy itself.
 * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
 * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
 * "admin cannot fallback to proxy target".
 *
 * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
 * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
 * to sudden errors when trying to call a function from the proxy implementation.
 *
 * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
 * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
 */
contract TransparentUpgradeableProxy is ERC1967Proxy {
    /**
     * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
     * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
     */
    constructor(
        address _logic,
        address admin_,
        bytes memory _data
    ) payable ERC1967Proxy(_logic, _data) {
        assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
        _changeAdmin(admin_);
    }
    /**
     * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
     */
    modifier ifAdmin() {
        if (msg.sender == _getAdmin()) {
            _;
        } else {
            _fallback();
        }
    }
    /**
     * @dev Returns the current admin.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
     *
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
     */
    function admin() external ifAdmin returns (address admin_) {
        admin_ = _getAdmin();
    }
    /**
     * @dev Returns the current implementation.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
     *
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
     */
    function implementation() external ifAdmin returns (address implementation_) {
        implementation_ = _implementation();
    }
    /**
     * @dev Changes the admin of the proxy.
     *
     * Emits an {AdminChanged} event.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
     */
    function changeAdmin(address newAdmin) external virtual ifAdmin {
        _changeAdmin(newAdmin);
    }
    /**
     * @dev Upgrade the implementation of the proxy.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
     */
    function upgradeTo(address newImplementation) external ifAdmin {
        _upgradeToAndCall(newImplementation, bytes(""), false);
    }
    /**
     * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
     * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
     * proxied contract.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
     */
    function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
        _upgradeToAndCall(newImplementation, data, true);
    }
    /**
     * @dev Returns the current admin.
     */
    function _admin() internal view virtual returns (address) {
        return _getAdmin();
    }
    /**
     * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
     */
    function _beforeFallback() internal virtual override {
        require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
        super._beforeFallback();
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.
        return account.code.length > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
pragma solidity ^0.8.0;
/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC1967 implementation slot:
 * ```
 * contract ERC1967 {
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }
    struct BooleanSlot {
        bool value;
    }
    struct Bytes32Slot {
        bytes32 value;
    }
    struct Uint256Slot {
        uint256 value;
    }
    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        assembly {
            r.slot := slot
        }
    }
}

// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "./interfaces/IAuthorizer.sol";
import "./interfaces/IWETH.sol";
import "./VaultAuthorization.sol";
import "./FlashLoans.sol";
import "./Swaps.sol";
/**
 * @dev The `Vault` is Balancer V2's core contract. A single instance of it exists for the entire network, and it is the
 * entity used to interact with Pools by Liquidity Providers who join and exit them, Traders who swap, and Asset
 * Managers who withdraw and deposit tokens.
 *
 * The `Vault`'s source code is split among a number of sub-contracts, with the goal of improving readability and making
 * understanding the system easier. Most sub-contracts have been marked as `abstract` to explicitly indicate that only
 * the full `Vault` is meant to be deployed.
 *
 * Roughly speaking, these are the contents of each sub-contract:
 *
 *  - `AssetManagers`: Pool token Asset Manager registry, and Asset Manager interactions.
 *  - `Fees`: set and compute protocol fees.
 *  - `FlashLoans`: flash loan transfers and fees.
 *  - `PoolBalances`: Pool joins and exits.
 *  - `PoolRegistry`: Pool registration, ID management, and basic queries.
 *  - `PoolTokens`: Pool token registration and registration, and balance queries.
 *  - `Swaps`: Pool swaps.
 *  - `UserBalance`: manage user balances (Internal Balance operations and external balance transfers)
 *  - `VaultAuthorization`: access control, relayers and signature validation.
 *
 * Additionally, the different Pool specializations are handled by the `GeneralPoolsBalance`,
 * `MinimalSwapInfoPoolsBalance` and `TwoTokenPoolsBalance` sub-contracts, which in turn make use of the
 * `BalanceAllocation` library.
 *
 * The most important goal of the `Vault` is to make token swaps use as little gas as possible. This is reflected in a
 * multitude of design decisions, from minor things like the format used to store Pool IDs, to major features such as
 * the different Pool specialization settings.
 *
 * Finally, the large number of tasks carried out by the Vault means its bytecode is very large, close to exceeding
 * the contract size limit imposed by EIP 170 (https://eips.ethereum.org/EIPS/eip-170). Manual tuning of the source code
 * was required to improve code generation and bring the bytecode size below this limit. This includes extensive
 * utilization of `internal` functions (particularly inside modifiers), usage of named return arguments, dedicated
 * storage access methods, dynamic revert reason generation, and usage of inline assembly, to name a few.
 */
contract Vault is VaultAuthorization, FlashLoans, Swaps {
    constructor(
        IAuthorizer authorizer,
        IWETH weth,
        uint256 pauseWindowDuration,
        uint256 bufferPeriodDuration
    ) VaultAuthorization(authorizer) AssetHelpers(weth) TemporarilyPausable(pauseWindowDuration, bufferPeriodDuration) {
        // solhint-disable-previous-line no-empty-blocks
    }
    function setPaused(bool paused) external override nonReentrant authenticate {
        _setPaused(paused);
    }
    // solhint-disable-next-line func-name-mixedcase
    function WETH() external view override returns (IWETH) {
        return _WETH();
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
interface IAuthorizer {
    /**
     * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
     */
    function canPerform(
        bytes32 actionId,
        address account,
        address where
    ) external view returns (bool);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../../lib/openzeppelin/IERC20.sol";
/**
 * @dev Interface for the WETH token contract used internally for wrapping and unwrapping, to support
 * sending and receiving ETH in joins, swaps, and internal balance deposits and withdrawals.
 */
interface IWETH is IERC20 {
    function deposit() external payable;
    function withdraw(uint256 amount) external;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/helpers/BalancerErrors.sol";
import "../lib/helpers/Authentication.sol";
import "../lib/helpers/TemporarilyPausable.sol";
import "../lib/helpers/BalancerErrors.sol";
import "../lib/helpers/SignaturesValidator.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "./interfaces/IVault.sol";
import "./interfaces/IAuthorizer.sol";
/**
 * @dev Manages access control of Vault permissioned functions by relying on the Authorizer and signature validation.
 *
 * Additionally handles relayer access and approval.
 */
abstract contract VaultAuthorization is
    IVault,
    ReentrancyGuard,
    Authentication,
    SignaturesValidator,
    TemporarilyPausable
{
    // Ideally, we'd store the type hashes as immutable state variables to avoid computing the hash at runtime, but
    // unfortunately immutable variables cannot be used in assembly, so we just keep the precomputed hashes instead.
    // _JOIN_TYPE_HASH = keccak256("JoinPool(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
    bytes32 private constant _JOIN_TYPE_HASH = 0x3f7b71252bd19113ff48c19c6e004a9bcfcca320a0d74d58e85877cbd7dcae58;
    // _EXIT_TYPE_HASH = keccak256("ExitPool(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
    bytes32 private constant _EXIT_TYPE_HASH = 0x8bbc57f66ea936902f50a71ce12b92c43f3c5340bb40c27c4e90ab84eeae3353;
    // _SWAP_TYPE_HASH = keccak256("Swap(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
    bytes32 private constant _SWAP_TYPE_HASH = 0xe192dcbc143b1e244ad73b813fd3c097b832ad260a157340b4e5e5beda067abe;
    // _BATCH_SWAP_TYPE_HASH = keccak256("BatchSwap(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
    bytes32 private constant _BATCH_SWAP_TYPE_HASH = 0x9bfc43a4d98313c6766986ffd7c916c7481566d9f224c6819af0a53388aced3a;
    // _SET_RELAYER_TYPE_HASH =
    //     keccak256("SetRelayerApproval(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
    bytes32
        private constant _SET_RELAYER_TYPE_HASH = 0xa3f865aa351e51cfeb40f5178d1564bb629fe9030b83caf6361d1baaf5b90b5a;
    IAuthorizer private _authorizer;
    mapping(address => mapping(address => bool)) private _approvedRelayers;
    /**
     * @dev Reverts unless `user` is the caller, or the caller is approved by the Authorizer to call this function (that
     * is, it is a relayer for that function), and either:
     *  a) `user` approved the caller as a relayer (via `setRelayerApproval`), or
     *  b) a valid signature from them was appended to the calldata.
     *
     * Should only be applied to external functions.
     */
    modifier authenticateFor(address user) {
        _authenticateFor(user);
        _;
    }
    constructor(IAuthorizer authorizer)
        // The Vault is a singleton, so it simply uses its own address to disambiguate action identifiers.
        Authentication(bytes32(uint256(address(this))))
        SignaturesValidator("Balancer V2 Vault")
    {
        _setAuthorizer(authorizer);
    }
    function setAuthorizer(IAuthorizer newAuthorizer) external override nonReentrant authenticate {
        _setAuthorizer(newAuthorizer);
    }
    function _setAuthorizer(IAuthorizer newAuthorizer) private {
        emit AuthorizerChanged(newAuthorizer);
        _authorizer = newAuthorizer;
    }
    function getAuthorizer() external view override returns (IAuthorizer) {
        return _authorizer;
    }
    function setRelayerApproval(
        address sender,
        address relayer,
        bool approved
    ) external override nonReentrant whenNotPaused authenticateFor(sender) {
        _approvedRelayers[sender][relayer] = approved;
        emit RelayerApprovalChanged(relayer, sender, approved);
    }
    function hasApprovedRelayer(address user, address relayer) external view override returns (bool) {
        return _hasApprovedRelayer(user, relayer);
    }
    /**
     * @dev Reverts unless `user` is the caller, or the caller is approved by the Authorizer to call the entry point
     * function (that is, it is a relayer for that function) and either:
     *  a) `user` approved the caller as a relayer (via `setRelayerApproval`), or
     *  b) a valid signature from them was appended to the calldata.
     */
    function _authenticateFor(address user) internal {
        if (msg.sender != user) {
            // In this context, 'permission to call a function' means 'being a relayer for a function'.
            _authenticateCaller();
            // Being a relayer is not sufficient: `user` must have also approved the caller either via
            // `setRelayerApproval`, or by providing a signature appended to the calldata.
            if (!_hasApprovedRelayer(user, msg.sender)) {
                _validateSignature(user, Errors.USER_DOESNT_ALLOW_RELAYER);
            }
        }
    }
    /**
     * @dev Returns true if `user` approved `relayer` to act as a relayer for them.
     */
    function _hasApprovedRelayer(address user, address relayer) internal view returns (bool) {
        return _approvedRelayers[user][relayer];
    }
    function _canPerform(bytes32 actionId, address user) internal view override returns (bool) {
        // Access control is delegated to the Authorizer.
        return _authorizer.canPerform(actionId, user, address(this));
    }
    function _typeHash() internal pure override returns (bytes32 hash) {
        // This is a simple switch-case statement, trivially written in Solidity by chaining else-if statements, but the
        // assembly implementation results in much denser bytecode.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            // The function selector is located at the first 4 bytes of calldata. We copy the first full calldata
            // 256 word, and then perform a logical shift to the right, moving the selector to the least significant
            // 4 bytes.
            let selector := shr(224, calldataload(0))
            // With the selector in the least significant 4 bytes, we can use 4 byte literals with leading zeros,
            // resulting in dense bytecode (PUSH4 opcodes).
            switch selector
                case 0xb95cac28 {
                    hash := _JOIN_TYPE_HASH
                }
                case 0x8bdb3913 {
                    hash := _EXIT_TYPE_HASH
                }
                case 0x52bbbe29 {
                    hash := _SWAP_TYPE_HASH
                }
                case 0x945bcec9 {
                    hash := _BATCH_SWAP_TYPE_HASH
                }
                case 0xfa6e671d {
                    hash := _SET_RELAYER_TYPE_HASH
                }
                default {
                    hash := 0x0000000000000000000000000000000000000000000000000000000000000000
                }
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
// This flash loan provider was based on the Aave protocol's open source
// implementation and terminology and interfaces are intentionally kept
// similar
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/helpers/BalancerErrors.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "./Fees.sol";
import "./interfaces/IFlashLoanRecipient.sol";
/**
 * @dev Handles Flash Loans through the Vault. Calls the `receiveFlashLoan` hook on the flash loan recipient
 * contract, which implements the `IFlashLoanRecipient` interface.
 */
abstract contract FlashLoans is Fees, ReentrancyGuard, TemporarilyPausable {
    using SafeERC20 for IERC20;
    function flashLoan(
        IFlashLoanRecipient recipient,
        IERC20[] memory tokens,
        uint256[] memory amounts,
        bytes memory userData
    ) external override nonReentrant whenNotPaused {
        InputHelpers.ensureInputLengthMatch(tokens.length, amounts.length);
        uint256[] memory feeAmounts = new uint256[](tokens.length);
        uint256[] memory preLoanBalances = new uint256[](tokens.length);
        // Used to ensure `tokens` is sorted in ascending order, which ensures token uniqueness.
        IERC20 previousToken = IERC20(0);
        for (uint256 i = 0; i < tokens.length; ++i) {
            IERC20 token = tokens[i];
            uint256 amount = amounts[i];
            _require(token > previousToken, token == IERC20(0) ? Errors.ZERO_TOKEN : Errors.UNSORTED_TOKENS);
            previousToken = token;
            preLoanBalances[i] = token.balanceOf(address(this));
            feeAmounts[i] = _calculateFlashLoanFeeAmount(amount);
            _require(preLoanBalances[i] >= amount, Errors.INSUFFICIENT_FLASH_LOAN_BALANCE);
            token.safeTransfer(address(recipient), amount);
        }
        recipient.receiveFlashLoan(tokens, amounts, feeAmounts, userData);
        for (uint256 i = 0; i < tokens.length; ++i) {
            IERC20 token = tokens[i];
            uint256 preLoanBalance = preLoanBalances[i];
            // Checking for loan repayment first (without accounting for fees) makes for simpler debugging, and results
            // in more accurate revert reasons if the flash loan protocol fee percentage is zero.
            uint256 postLoanBalance = token.balanceOf(address(this));
            _require(postLoanBalance >= preLoanBalance, Errors.INVALID_POST_LOAN_BALANCE);
            // No need for checked arithmetic since we know the loan was fully repaid.
            uint256 receivedFeeAmount = postLoanBalance - preLoanBalance;
            _require(receivedFeeAmount >= feeAmounts[i], Errors.INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT);
            _payFeeAmount(token, receivedFeeAmount);
            emit FlashLoan(recipient, token, amounts[i], receivedFeeAmount);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/math/Math.sol";
import "../lib/helpers/BalancerErrors.sol";
import "../lib/helpers/InputHelpers.sol";
import "../lib/openzeppelin/EnumerableMap.sol";
import "../lib/openzeppelin/EnumerableSet.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "../lib/openzeppelin/SafeCast.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "./PoolBalances.sol";
import "./interfaces/IPoolSwapStructs.sol";
import "./interfaces/IGeneralPool.sol";
import "./interfaces/IMinimalSwapInfoPool.sol";
import "./balances/BalanceAllocation.sol";
/**
 * Implements the Vault's high-level swap functionality.
 *
 * Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. They need not trust the Pool
 * contracts to do this: all security checks are made by the Vault.
 *
 * The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
 * In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
 * and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
 * More complex swaps, such as one 'token in' to multiple tokens out can be achieved by batching together
 * individual swaps.
 */
abstract contract Swaps is ReentrancyGuard, PoolBalances {
    using SafeERC20 for IERC20;
    using EnumerableSet for EnumerableSet.AddressSet;
    using EnumerableMap for EnumerableMap.IERC20ToBytes32Map;
    using Math for int256;
    using Math for uint256;
    using SafeCast for uint256;
    using BalanceAllocation for bytes32;
    function swap(
        SingleSwap memory singleSwap,
        FundManagement memory funds,
        uint256 limit,
        uint256 deadline
    )
        external
        payable
        override
        nonReentrant
        whenNotPaused
        authenticateFor(funds.sender)
        returns (uint256 amountCalculated)
    {
        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
        // solhint-disable-next-line not-rely-on-time
        _require(block.timestamp <= deadline, Errors.SWAP_DEADLINE);
        // This revert reason is for consistency with `batchSwap`: an equivalent `swap` performed using that function
        // would result in this error.
        _require(singleSwap.amount > 0, Errors.UNKNOWN_AMOUNT_IN_FIRST_SWAP);
        IERC20 tokenIn = _translateToIERC20(singleSwap.assetIn);
        IERC20 tokenOut = _translateToIERC20(singleSwap.assetOut);
        _require(tokenIn != tokenOut, Errors.CANNOT_SWAP_SAME_TOKEN);
        // Initializing each struct field one-by-one uses less gas than setting all at once.
        IPoolSwapStructs.SwapRequest memory poolRequest;
        poolRequest.poolId = singleSwap.poolId;
        poolRequest.kind = singleSwap.kind;
        poolRequest.tokenIn = tokenIn;
        poolRequest.tokenOut = tokenOut;
        poolRequest.amount = singleSwap.amount;
        poolRequest.userData = singleSwap.userData;
        poolRequest.from = funds.sender;
        poolRequest.to = funds.recipient;
        // The lastChangeBlock field is left uninitialized.
        uint256 amountIn;
        uint256 amountOut;
        (amountCalculated, amountIn, amountOut) = _swapWithPool(poolRequest);
        _require(singleSwap.kind == SwapKind.GIVEN_IN ? amountOut >= limit : amountIn <= limit, Errors.SWAP_LIMIT);
        _receiveAsset(singleSwap.assetIn, amountIn, funds.sender, funds.fromInternalBalance);
        _sendAsset(singleSwap.assetOut, amountOut, funds.recipient, funds.toInternalBalance);
        // If the asset in is ETH, then `amountIn` ETH was wrapped into WETH.
        _handleRemainingEth(_isETH(singleSwap.assetIn) ? amountIn : 0);
    }
    function batchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds,
        int256[] memory limits,
        uint256 deadline
    )
        external
        payable
        override
        nonReentrant
        whenNotPaused
        authenticateFor(funds.sender)
        returns (int256[] memory assetDeltas)
    {
        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
        // solhint-disable-next-line not-rely-on-time
        _require(block.timestamp <= deadline, Errors.SWAP_DEADLINE);
        InputHelpers.ensureInputLengthMatch(assets.length, limits.length);
        // Perform the swaps, updating the Pool token balances and computing the net Vault asset deltas.
        assetDeltas = _swapWithPools(swaps, assets, funds, kind);
        // Process asset deltas, by either transferring assets from the sender (for positive deltas) or to the recipient
        // (for negative deltas).
        uint256 wrappedEth = 0;
        for (uint256 i = 0; i < assets.length; ++i) {
            IAsset asset = assets[i];
            int256 delta = assetDeltas[i];
            _require(delta <= limits[i], Errors.SWAP_LIMIT);
            if (delta > 0) {
                uint256 toReceive = uint256(delta);
                _receiveAsset(asset, toReceive, funds.sender, funds.fromInternalBalance);
                if (_isETH(asset)) {
                    wrappedEth = wrappedEth.add(toReceive);
                }
            } else if (delta < 0) {
                uint256 toSend = uint256(-delta);
                _sendAsset(asset, toSend, funds.recipient, funds.toInternalBalance);
            }
        }
        // Handle any used and remaining ETH.
        _handleRemainingEth(wrappedEth);
    }
    // For `_swapWithPools` to handle both 'given in' and 'given out' swaps, it internally tracks the 'given' amount
    // (supplied by the caller), and the 'calculated' amount (returned by the Pool in response to the swap request).
    /**
     * @dev Given the two swap tokens and the swap kind, returns which one is the 'given' token (the token whose
     * amount is supplied by the caller).
     */
    function _tokenGiven(
        SwapKind kind,
        IERC20 tokenIn,
        IERC20 tokenOut
    ) private pure returns (IERC20) {
        return kind == SwapKind.GIVEN_IN ? tokenIn : tokenOut;
    }
    /**
     * @dev Given the two swap tokens and the swap kind, returns which one is the 'calculated' token (the token whose
     * amount is calculated by the Pool).
     */
    function _tokenCalculated(
        SwapKind kind,
        IERC20 tokenIn,
        IERC20 tokenOut
    ) private pure returns (IERC20) {
        return kind == SwapKind.GIVEN_IN ? tokenOut : tokenIn;
    }
    /**
     * @dev Returns an ordered pair (amountIn, amountOut) given the 'given' and 'calculated' amounts, and the swap kind.
     */
    function _getAmounts(
        SwapKind kind,
        uint256 amountGiven,
        uint256 amountCalculated
    ) private pure returns (uint256 amountIn, uint256 amountOut) {
        if (kind == SwapKind.GIVEN_IN) {
            (amountIn, amountOut) = (amountGiven, amountCalculated);
        } else {
            // SwapKind.GIVEN_OUT
            (amountIn, amountOut) = (amountCalculated, amountGiven);
        }
    }
    /**
     * @dev Performs all `swaps`, calling swap hooks on the Pool contracts and updating their balances. Does not cause
     * any transfer of tokens - instead it returns the net Vault token deltas: positive if the Vault should receive
     * tokens, and negative if it should send them.
     */
    function _swapWithPools(
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds,
        SwapKind kind
    ) private returns (int256[] memory assetDeltas) {
        assetDeltas = new int256[](assets.length);
        // These variables could be declared inside the loop, but that causes the compiler to allocate memory on each
        // loop iteration, increasing gas costs.
        BatchSwapStep memory batchSwapStep;
        IPoolSwapStructs.SwapRequest memory poolRequest;
        // These store data about the previous swap here to implement multihop logic across swaps.
        IERC20 previousTokenCalculated;
        uint256 previousAmountCalculated;
        for (uint256 i = 0; i < swaps.length; ++i) {
            batchSwapStep = swaps[i];
            bool withinBounds = batchSwapStep.assetInIndex < assets.length &&
                batchSwapStep.assetOutIndex < assets.length;
            _require(withinBounds, Errors.OUT_OF_BOUNDS);
            IERC20 tokenIn = _translateToIERC20(assets[batchSwapStep.assetInIndex]);
            IERC20 tokenOut = _translateToIERC20(assets[batchSwapStep.assetOutIndex]);
            _require(tokenIn != tokenOut, Errors.CANNOT_SWAP_SAME_TOKEN);
            // Sentinel value for multihop logic
            if (batchSwapStep.amount == 0) {
                // When the amount given is zero, we use the calculated amount for the previous swap, as long as the
                // current swap's given token is the previous calculated token. This makes it possible to swap a
                // given amount of token A for token B, and then use the resulting token B amount to swap for token C.
                _require(i > 0, Errors.UNKNOWN_AMOUNT_IN_FIRST_SWAP);
                bool usingPreviousToken = previousTokenCalculated == _tokenGiven(kind, tokenIn, tokenOut);
                _require(usingPreviousToken, Errors.MALCONSTRUCTED_MULTIHOP_SWAP);
                batchSwapStep.amount = previousAmountCalculated;
            }
            // Initializing each struct field one-by-one uses less gas than setting all at once
            poolRequest.poolId = batchSwapStep.poolId;
            poolRequest.kind = kind;
            poolRequest.tokenIn = tokenIn;
            poolRequest.tokenOut = tokenOut;
            poolRequest.amount = batchSwapStep.amount;
            poolRequest.userData = batchSwapStep.userData;
            poolRequest.from = funds.sender;
            poolRequest.to = funds.recipient;
            // The lastChangeBlock field is left uninitialized
            uint256 amountIn;
            uint256 amountOut;
            (previousAmountCalculated, amountIn, amountOut) = _swapWithPool(poolRequest);
            previousTokenCalculated = _tokenCalculated(kind, tokenIn, tokenOut);
            // Accumulate Vault deltas across swaps
            assetDeltas[batchSwapStep.assetInIndex] = assetDeltas[batchSwapStep.assetInIndex].add(amountIn.toInt256());
            assetDeltas[batchSwapStep.assetOutIndex] = assetDeltas[batchSwapStep.assetOutIndex].sub(
                amountOut.toInt256()
            );
        }
    }
    /**
     * @dev Performs a swap according to the parameters specified in `request`, calling the Pool's contract hook and
     * updating the Pool's balance.
     *
     * Returns the amount of tokens going into or out of the Vault as a result of this swap, depending on the swap kind.
     */
    function _swapWithPool(IPoolSwapStructs.SwapRequest memory request)
        private
        returns (
            uint256 amountCalculated,
            uint256 amountIn,
            uint256 amountOut
        )
    {
        // Get the calculated amount from the Pool and update its balances
        address pool = _getPoolAddress(request.poolId);
        PoolSpecialization specialization = _getPoolSpecialization(request.poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            amountCalculated = _processTwoTokenPoolSwapRequest(request, IMinimalSwapInfoPool(pool));
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            amountCalculated = _processMinimalSwapInfoPoolSwapRequest(request, IMinimalSwapInfoPool(pool));
        } else {
            // PoolSpecialization.GENERAL
            amountCalculated = _processGeneralPoolSwapRequest(request, IGeneralPool(pool));
        }
        (amountIn, amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
        emit Swap(request.poolId, request.tokenIn, request.tokenOut, amountIn, amountOut);
    }
    function _processTwoTokenPoolSwapRequest(IPoolSwapStructs.SwapRequest memory request, IMinimalSwapInfoPool pool)
        private
        returns (uint256 amountCalculated)
    {
        // For gas efficiency reasons, this function uses low-level knowledge of how Two Token Pool balances are
        // stored internally, instead of using getters and setters for all operations.
        (
            bytes32 tokenABalance,
            bytes32 tokenBBalance,
            TwoTokenPoolBalances storage poolBalances
        ) = _getTwoTokenPoolSharedBalances(request.poolId, request.tokenIn, request.tokenOut);
        // We have the two Pool balances, but we don't know which one is 'token in' or 'token out'.
        bytes32 tokenInBalance;
        bytes32 tokenOutBalance;
        // In Two Token Pools, token A has a smaller address than token B
        if (request.tokenIn < request.tokenOut) {
            // in is A, out is B
            tokenInBalance = tokenABalance;
            tokenOutBalance = tokenBBalance;
        } else {
            // in is B, out is A
            tokenOutBalance = tokenABalance;
            tokenInBalance = tokenBBalance;
        }
        // Perform the swap request and compute the new balances for 'token in' and 'token out' after the swap
        (tokenInBalance, tokenOutBalance, amountCalculated) = _callMinimalSwapInfoPoolOnSwapHook(
            request,
            pool,
            tokenInBalance,
            tokenOutBalance
        );
        // We check the token ordering again to create the new shared cash packed struct
        poolBalances.sharedCash = request.tokenIn < request.tokenOut
            ? BalanceAllocation.toSharedCash(tokenInBalance, tokenOutBalance) // in is A, out is B
            : BalanceAllocation.toSharedCash(tokenOutBalance, tokenInBalance); // in is B, out is A
    }
    function _processMinimalSwapInfoPoolSwapRequest(
        IPoolSwapStructs.SwapRequest memory request,
        IMinimalSwapInfoPool pool
    ) private returns (uint256 amountCalculated) {
        bytes32 tokenInBalance = _getMinimalSwapInfoPoolBalance(request.poolId, request.tokenIn);
        bytes32 tokenOutBalance = _getMinimalSwapInfoPoolBalance(request.poolId, request.tokenOut);
        // Perform the swap request and compute the new balances for 'token in' and 'token out' after the swap
        (tokenInBalance, tokenOutBalance, amountCalculated) = _callMinimalSwapInfoPoolOnSwapHook(
            request,
            pool,
            tokenInBalance,
            tokenOutBalance
        );
        _minimalSwapInfoPoolsBalances[request.poolId][request.tokenIn] = tokenInBalance;
        _minimalSwapInfoPoolsBalances[request.poolId][request.tokenOut] = tokenOutBalance;
    }
    /**
     * @dev Calls the onSwap hook for a Pool that implements IMinimalSwapInfoPool: both Minimal Swap Info and Two Token
     * Pools do this.
     */
    function _callMinimalSwapInfoPoolOnSwapHook(
        IPoolSwapStructs.SwapRequest memory request,
        IMinimalSwapInfoPool pool,
        bytes32 tokenInBalance,
        bytes32 tokenOutBalance
    )
        internal
        returns (
            bytes32 newTokenInBalance,
            bytes32 newTokenOutBalance,
            uint256 amountCalculated
        )
    {
        uint256 tokenInTotal = tokenInBalance.total();
        uint256 tokenOutTotal = tokenOutBalance.total();
        request.lastChangeBlock = Math.max(tokenInBalance.lastChangeBlock(), tokenOutBalance.lastChangeBlock());
        // Perform the swap request callback, and compute the new balances for 'token in' and 'token out' after the swap
        amountCalculated = pool.onSwap(request, tokenInTotal, tokenOutTotal);
        (uint256 amountIn, uint256 amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
        newTokenInBalance = tokenInBalance.increaseCash(amountIn);
        newTokenOutBalance = tokenOutBalance.decreaseCash(amountOut);
    }
    function _processGeneralPoolSwapRequest(IPoolSwapStructs.SwapRequest memory request, IGeneralPool pool)
        private
        returns (uint256 amountCalculated)
    {
        bytes32 tokenInBalance;
        bytes32 tokenOutBalance;
        // We access both token indexes without checking existence, because we will do it manually immediately after.
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[request.poolId];
        uint256 indexIn = poolBalances.unchecked_indexOf(request.tokenIn);
        uint256 indexOut = poolBalances.unchecked_indexOf(request.tokenOut);
        if (indexIn == 0 || indexOut == 0) {
            // The tokens might not be registered because the Pool itself is not registered. We check this to provide a
            // more accurate revert reason.
            _ensureRegisteredPool(request.poolId);
            _revert(Errors.TOKEN_NOT_REGISTERED);
        }
        // EnumerableMap stores indices *plus one* to use the zero index as a sentinel value - because these are valid,
        // we can undo this.
        indexIn -= 1;
        indexOut -= 1;
        uint256 tokenAmount = poolBalances.length();
        uint256[] memory currentBalances = new uint256[](tokenAmount);
        request.lastChangeBlock = 0;
        for (uint256 i = 0; i < tokenAmount; i++) {
            // Because the iteration is bounded by `tokenAmount`, and no tokens are registered or deregistered here, we
            // know `i` is a valid token index and can use `unchecked_valueAt` to save storage reads.
            bytes32 balance = poolBalances.unchecked_valueAt(i);
            currentBalances[i] = balance.total();
            request.lastChangeBlock = Math.max(request.lastChangeBlock, balance.lastChangeBlock());
            if (i == indexIn) {
                tokenInBalance = balance;
            } else if (i == indexOut) {
                tokenOutBalance = balance;
            }
        }
        // Perform the swap request callback and compute the new balances for 'token in' and 'token out' after the swap
        amountCalculated = pool.onSwap(request, currentBalances, indexIn, indexOut);
        (uint256 amountIn, uint256 amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
        tokenInBalance = tokenInBalance.increaseCash(amountIn);
        tokenOutBalance = tokenOutBalance.decreaseCash(amountOut);
        // Because no tokens were registered or deregistered between now or when we retrieved the indexes for
        // 'token in' and 'token out', we can use `unchecked_setAt` to save storage reads.
        poolBalances.unchecked_setAt(indexIn, tokenInBalance);
        poolBalances.unchecked_setAt(indexOut, tokenOutBalance);
    }
    // This function is not marked as `nonReentrant` because the underlying mechanism relies on reentrancy
    function queryBatchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds
    ) external override returns (int256[] memory) {
        // In order to accurately 'simulate' swaps, this function actually does perform the swaps, including calling the
        // Pool hooks and updating balances in storage. However, once it computes the final Vault Deltas, it
        // reverts unconditionally, returning this array as the revert data.
        //
        // By wrapping this reverting call, we can decode the deltas 'returned' and return them as a normal Solidity
        // function would. The only caveat is the function becomes non-view, but off-chain clients can still call it
        // via eth_call to get the expected result.
        //
        // This technique was inspired by the work from the Gnosis team in the Gnosis Safe contract:
        // https://github.com/gnosis/safe-contracts/blob/v1.2.0/contracts/GnosisSafe.sol#L265
        //
        // Most of this function is implemented using inline assembly, as the actual work it needs to do is not
        // significant, and Solidity is not particularly well-suited to generate this behavior, resulting in a large
        // amount of generated bytecode.
        if (msg.sender != address(this)) {
            // We perform an external call to ourselves, forwarding the same calldata. In this call, the else clause of
            // the preceding if statement will be executed instead.
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, ) = address(this).call(msg.data);
            // solhint-disable-next-line no-inline-assembly
            assembly {
                // This call should always revert to decode the actual asset deltas from the revert reason
                switch success
                    case 0 {
                        // Note we are manually writing the memory slot 0. We can safely overwrite whatever is
                        // stored there as we take full control of the execution and then immediately return.
                        // We copy the first 4 bytes to check if it matches with the expected signature, otherwise
                        // there was another revert reason and we should forward it.
                        returndatacopy(0, 0, 0x04)
                        let error := and(mload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
                        // If the first 4 bytes don't match with the expected signature, we forward the revert reason.
                        if eq(eq(error, 0xfa61cc1200000000000000000000000000000000000000000000000000000000), 0) {
                            returndatacopy(0, 0, returndatasize())
                            revert(0, returndatasize())
                        }
                        // The returndata contains the signature, followed by the raw memory representation of an array:
                        // length + data. We need to return an ABI-encoded representation of this array.
                        // An ABI-encoded array contains an additional field when compared to its raw memory
                        // representation: an offset to the location of the length. The offset itself is 32 bytes long,
                        // so the smallest value we  can use is 32 for the data to be located immediately after it.
                        mstore(0, 32)
                        // We now copy the raw memory array from returndata into memory. Since the offset takes up 32
                        // bytes, we start copying at address 0x20. We also get rid of the error signature, which takes
                        // the first four bytes of returndata.
                        let size := sub(returndatasize(), 0x04)
                        returndatacopy(0x20, 0x04, size)
                        // We finally return the ABI-encoded array, which has a total length equal to that of the array
                        // (returndata), plus the 32 bytes for the offset.
                        return(0, add(size, 32))
                    }
                    default {
                        // This call should always revert, but we fail nonetheless if that didn't happen
                        invalid()
                    }
            }
        } else {
            int256[] memory deltas = _swapWithPools(swaps, assets, funds, kind);
            // solhint-disable-next-line no-inline-assembly
            assembly {
                // We will return a raw representation of the array in memory, which is composed of a 32 byte length,
                // followed by the 32 byte int256 values. Because revert expects a size in bytes, we multiply the array
                // length (stored at `deltas`) by 32.
                let size := mul(mload(deltas), 32)
                // We send one extra value for the error signature "QueryError(int256[])" which is 0xfa61cc12.
                // We store it in the previous slot to the `deltas` array. We know there will be at least one available
                // slot due to how the memory scratch space works.
                // We can safely overwrite whatever is stored in this slot as we will revert immediately after that.
                mstore(sub(deltas, 0x20), 0x00000000000000000000000000000000000000000000000000000000fa61cc12)
                let start := sub(deltas, 0x04)
                // When copying from `deltas` into returndata, we copy an additional 36 bytes to also return the array's
                // length and the error signature.
                revert(start, add(size, 36))
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
// solhint-disable
/**
 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
 * supported.
 */
function _require(bool condition, uint256 errorCode) pure {
    if (!condition) _revert(errorCode);
}
/**
 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
 */
function _revert(uint256 errorCode) pure {
    // We're going to dynamically create a revert string based on the error code, with the following format:
    // 'BAL#{errorCode}'
    // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
    //
    // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
    // number (8 to 16 bits) than the individual string characters.
    //
    // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
    assembly {
        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
        // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
        // the '0' character.
        let units := add(mod(errorCode, 10), 0x30)
        errorCode := div(errorCode, 10)
        let tenths := add(mod(errorCode, 10), 0x30)
        errorCode := div(errorCode, 10)
        let hundreds := add(mod(errorCode, 10), 0x30)
        // With the individual characters, we can now construct the full string. The "BAL#" part is a known constant
        // (0x42414c23): we simply shift this by 24 (to provide space for the 3 bytes of the error code), and add the
        // characters to it, each shifted by a multiple of 8.
        // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
        // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
        // array).
        let revertReason := shl(200, add(0x42414c23000000, add(add(units, shl(8, tenths)), shl(16, hundreds))))
        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
        // message will have the following layout:
        // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]
        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
        // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
        // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
        // The string length is fixed: 7 characters.
        mstore(0x24, 7)
        // Finally, the string itself is stored.
        mstore(0x44, revertReason)
        // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
        revert(0, 100)
    }
}
library Errors {
    // Math
    uint256 internal constant ADD_OVERFLOW = 0;
    uint256 internal constant SUB_OVERFLOW = 1;
    uint256 internal constant SUB_UNDERFLOW = 2;
    uint256 internal constant MUL_OVERFLOW = 3;
    uint256 internal constant ZERO_DIVISION = 4;
    uint256 internal constant DIV_INTERNAL = 5;
    uint256 internal constant X_OUT_OF_BOUNDS = 6;
    uint256 internal constant Y_OUT_OF_BOUNDS = 7;
    uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
    uint256 internal constant INVALID_EXPONENT = 9;
    // Input
    uint256 internal constant OUT_OF_BOUNDS = 100;
    uint256 internal constant UNSORTED_ARRAY = 101;
    uint256 internal constant UNSORTED_TOKENS = 102;
    uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
    uint256 internal constant ZERO_TOKEN = 104;
    // Shared pools
    uint256 internal constant MIN_TOKENS = 200;
    uint256 internal constant MAX_TOKENS = 201;
    uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
    uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
    uint256 internal constant MINIMUM_BPT = 204;
    uint256 internal constant CALLER_NOT_VAULT = 205;
    uint256 internal constant UNINITIALIZED = 206;
    uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
    uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
    uint256 internal constant EXPIRED_PERMIT = 209;
    // Pools
    uint256 internal constant MIN_AMP = 300;
    uint256 internal constant MAX_AMP = 301;
    uint256 internal constant MIN_WEIGHT = 302;
    uint256 internal constant MAX_STABLE_TOKENS = 303;
    uint256 internal constant MAX_IN_RATIO = 304;
    uint256 internal constant MAX_OUT_RATIO = 305;
    uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
    uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
    uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
    uint256 internal constant INVALID_TOKEN = 309;
    uint256 internal constant UNHANDLED_JOIN_KIND = 310;
    uint256 internal constant ZERO_INVARIANT = 311;
    // Lib
    uint256 internal constant REENTRANCY = 400;
    uint256 internal constant SENDER_NOT_ALLOWED = 401;
    uint256 internal constant PAUSED = 402;
    uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
    uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
    uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
    uint256 internal constant INSUFFICIENT_BALANCE = 406;
    uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
    uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
    uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
    uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
    uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
    uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
    uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
    uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
    uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
    uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
    uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
    uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
    uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
    uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
    uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
    uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
    uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
    uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
    // Vault
    uint256 internal constant INVALID_POOL_ID = 500;
    uint256 internal constant CALLER_NOT_POOL = 501;
    uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
    uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
    uint256 internal constant INVALID_SIGNATURE = 504;
    uint256 internal constant EXIT_BELOW_MIN = 505;
    uint256 internal constant JOIN_ABOVE_MAX = 506;
    uint256 internal constant SWAP_LIMIT = 507;
    uint256 internal constant SWAP_DEADLINE = 508;
    uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
    uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
    uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
    uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
    uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
    uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
    uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
    uint256 internal constant INSUFFICIENT_ETH = 516;
    uint256 internal constant UNALLOCATED_ETH = 517;
    uint256 internal constant ETH_TRANSFER = 518;
    uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
    uint256 internal constant TOKENS_MISMATCH = 520;
    uint256 internal constant TOKEN_NOT_REGISTERED = 521;
    uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
    uint256 internal constant TOKENS_ALREADY_SET = 523;
    uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
    uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
    uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
    uint256 internal constant POOL_NO_TOKENS = 527;
    uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;
    // Fees
    uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
    uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
    uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "./BalancerErrors.sol";
import "./IAuthentication.sol";
/**
 * @dev Building block for performing access control on external functions.
 *
 * This contract is used via the `authenticate` modifier (or the `_authenticateCaller` function), which can be applied
 * to external functions to only make them callable by authorized accounts.
 *
 * Derived contracts must implement the `_canPerform` function, which holds the actual access control logic.
 */
abstract contract Authentication is IAuthentication {
    bytes32 private immutable _actionIdDisambiguator;
    /**
     * @dev The main purpose of the `actionIdDisambiguator` is to prevent accidental function selector collisions in
     * multi contract systems.
     *
     * There are two main uses for it:
     *  - if the contract is a singleton, any unique identifier can be used to make the associated action identifiers
     *    unique. The contract's own address is a good option.
     *  - if the contract belongs to a family that shares action identifiers for the same functions, an identifier
     *    shared by the entire family (and no other contract) should be used instead.
     */
    constructor(bytes32 actionIdDisambiguator) {
        _actionIdDisambiguator = actionIdDisambiguator;
    }
    /**
     * @dev Reverts unless the caller is allowed to call this function. Should only be applied to external functions.
     */
    modifier authenticate() {
        _authenticateCaller();
        _;
    }
    /**
     * @dev Reverts unless the caller is allowed to call the entry point function.
     */
    function _authenticateCaller() internal view {
        bytes32 actionId = getActionId(msg.sig);
        _require(_canPerform(actionId, msg.sender), Errors.SENDER_NOT_ALLOWED);
    }
    function getActionId(bytes4 selector) public view override returns (bytes32) {
        // Each external function is dynamically assigned an action identifier as the hash of the disambiguator and the
        // function selector. Disambiguation is necessary to avoid potential collisions in the function selectors of
        // multiple contracts.
        return keccak256(abi.encodePacked(_actionIdDisambiguator, selector));
    }
    function _canPerform(bytes32 actionId, address user) internal view virtual returns (bool);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "./BalancerErrors.sol";
import "./ITemporarilyPausable.sol";
/**
 * @dev Allows for a contract to be paused during an initial period after deployment, disabling functionality. Can be
 * used as an emergency switch in case a security vulnerability or threat is identified.
 *
 * The contract can only be paused during the Pause Window, a period that starts at deployment. It can also be
 * unpaused and repaused any number of times during this period. This is intended to serve as a safety measure: it lets
 * system managers react quickly to potentially dangerous situations, knowing that this action is reversible if careful
 * analysis later determines there was a false alarm.
 *
 * If the contract is paused when the Pause Window finishes, it will remain in the paused state through an additional
 * Buffer Period, after which it will be automatically unpaused forever. This is to ensure there is always enough time
 * to react to an emergency, even if the threat is discovered shortly before the Pause Window expires.
 *
 * Note that since the contract can only be paused within the Pause Window, unpausing during the Buffer Period is
 * irreversible.
 */
abstract contract TemporarilyPausable is ITemporarilyPausable {
    // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
    // solhint-disable not-rely-on-time
    uint256 private constant _MAX_PAUSE_WINDOW_DURATION = 90 days;
    uint256 private constant _MAX_BUFFER_PERIOD_DURATION = 30 days;
    uint256 private immutable _pauseWindowEndTime;
    uint256 private immutable _bufferPeriodEndTime;
    bool private _paused;
    constructor(uint256 pauseWindowDuration, uint256 bufferPeriodDuration) {
        _require(pauseWindowDuration <= _MAX_PAUSE_WINDOW_DURATION, Errors.MAX_PAUSE_WINDOW_DURATION);
        _require(bufferPeriodDuration <= _MAX_BUFFER_PERIOD_DURATION, Errors.MAX_BUFFER_PERIOD_DURATION);
        uint256 pauseWindowEndTime = block.timestamp + pauseWindowDuration;
        _pauseWindowEndTime = pauseWindowEndTime;
        _bufferPeriodEndTime = pauseWindowEndTime + bufferPeriodDuration;
    }
    /**
     * @dev Reverts if the contract is paused.
     */
    modifier whenNotPaused() {
        _ensureNotPaused();
        _;
    }
    /**
     * @dev Returns the current contract pause status, as well as the end times of the Pause Window and Buffer
     * Period.
     */
    function getPausedState()
        external
        view
        override
        returns (
            bool paused,
            uint256 pauseWindowEndTime,
            uint256 bufferPeriodEndTime
        )
    {
        paused = !_isNotPaused();
        pauseWindowEndTime = _getPauseWindowEndTime();
        bufferPeriodEndTime = _getBufferPeriodEndTime();
    }
    /**
     * @dev Sets the pause state to `paused`. The contract can only be paused until the end of the Pause Window, and
     * unpaused until the end of the Buffer Period.
     *
     * Once the Buffer Period expires, this function reverts unconditionally.
     */
    function _setPaused(bool paused) internal {
        if (paused) {
            _require(block.timestamp < _getPauseWindowEndTime(), Errors.PAUSE_WINDOW_EXPIRED);
        } else {
            _require(block.timestamp < _getBufferPeriodEndTime(), Errors.BUFFER_PERIOD_EXPIRED);
        }
        _paused = paused;
        emit PausedStateChanged(paused);
    }
    /**
     * @dev Reverts if the contract is paused.
     */
    function _ensureNotPaused() internal view {
        _require(_isNotPaused(), Errors.PAUSED);
    }
    /**
     * @dev Returns true if the contract is unpaused.
     *
     * Once the Buffer Period expires, the gas cost of calling this function is reduced dramatically, as storage is no
     * longer accessed.
     */
    function _isNotPaused() internal view returns (bool) {
        // After the Buffer Period, the (inexpensive) timestamp check short-circuits the storage access.
        return block.timestamp > _getBufferPeriodEndTime() || !_paused;
    }
    // These getters lead to reduced bytecode size by inlining the immutable variables in a single place.
    function _getPauseWindowEndTime() private view returns (uint256) {
        return _pauseWindowEndTime;
    }
    function _getBufferPeriodEndTime() private view returns (uint256) {
        return _bufferPeriodEndTime;
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "./BalancerErrors.sol";
import "./ISignaturesValidator.sol";
import "../openzeppelin/EIP712.sol";
/**
 * @dev Utility for signing Solidity function calls.
 *
 * This contract relies on the fact that Solidity contracts can be called with extra calldata, and enables
 * meta-transaction schemes by appending an EIP712 signature of the original calldata at the end.
 *
 * Derived contracts must implement the `_typeHash` function to map function selectors to EIP712 structs.
 */
abstract contract SignaturesValidator is ISignaturesValidator, EIP712 {
    // The appended data consists of a deadline, plus the [v,r,s] signature. For simplicity, we use a full 256 bit slot
    // for each of these values, even if 'v' is typically an 8 bit value.
    uint256 internal constant _EXTRA_CALLDATA_LENGTH = 4 * 32;
    // Replay attack prevention for each user.
    mapping(address => uint256) internal _nextNonce;
    constructor(string memory name) EIP712(name, "1") {
        // solhint-disable-previous-line no-empty-blocks
    }
    function getDomainSeparator() external view override returns (bytes32) {
        return _domainSeparatorV4();
    }
    function getNextNonce(address user) external view override returns (uint256) {
        return _nextNonce[user];
    }
    /**
     * @dev Reverts with `errorCode` unless a valid signature for `user` was appended to the calldata.
     */
    function _validateSignature(address user, uint256 errorCode) internal {
        uint256 nextNonce = _nextNonce[user]++;
        _require(_isSignatureValid(user, nextNonce), errorCode);
    }
    function _isSignatureValid(address user, uint256 nonce) private view returns (bool) {
        uint256 deadline = _deadline();
        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
        // solhint-disable-next-line not-rely-on-time
        if (deadline < block.timestamp) {
            return false;
        }
        bytes32 typeHash = _typeHash();
        if (typeHash == bytes32(0)) {
            // Prevent accidental signature validation for functions that don't have an associated type hash.
            return false;
        }
        // All type hashes have this format: (bytes calldata, address sender, uint256 nonce, uint256 deadline).
        bytes32 structHash = keccak256(abi.encode(typeHash, keccak256(_calldata()), msg.sender, nonce, deadline));
        bytes32 digest = _hashTypedDataV4(structHash);
        (uint8 v, bytes32 r, bytes32 s) = _signature();
        address recoveredAddress = ecrecover(digest, v, r, s);
        // ecrecover returns the zero address on recover failure, so we need to handle that explicitly.
        return recoveredAddress != address(0) && recoveredAddress == user;
    }
    /**
     * @dev Returns the EIP712 type hash for the current entry point function, which can be identified by its function
     * selector (available as `msg.sig`).
     *
     * The type hash must conform to the following format:
     *  <name>(bytes calldata, address sender, uint256 nonce, uint256 deadline)
     *
     * If 0x00, all signatures will be considered invalid.
     */
    function _typeHash() internal view virtual returns (bytes32);
    /**
     * @dev Extracts the signature deadline from extra calldata.
     *
     * This function returns bogus data if no signature is included.
     */
    function _deadline() internal pure returns (uint256) {
        // The deadline is the first extra argument at the end of the original calldata.
        return uint256(_decodeExtraCalldataWord(0));
    }
    /**
     * @dev Extracts the signature parameters from extra calldata.
     *
     * This function returns bogus data if no signature is included. This is not a security risk, as that data would not
     * be considered a valid signature in the first place.
     */
    function _signature()
        internal
        pure
        returns (
            uint8 v,
            bytes32 r,
            bytes32 s
        )
    {
        // v, r and s are appended after the signature deadline, in that order.
        v = uint8(uint256(_decodeExtraCalldataWord(0x20)));
        r = _decodeExtraCalldataWord(0x40);
        s = _decodeExtraCalldataWord(0x60);
    }
    /**
     * @dev Returns the original calldata, without the extra bytes containing the signature.
     *
     * This function returns bogus data if no signature is included.
     */
    function _calldata() internal pure returns (bytes memory result) {
        result = msg.data; // A calldata to memory assignment results in memory allocation and copy of contents.
        if (result.length > _EXTRA_CALLDATA_LENGTH) {
            // solhint-disable-next-line no-inline-assembly
            assembly {
                // We simply overwrite the array length with the reduced one.
                mstore(result, sub(calldatasize(), _EXTRA_CALLDATA_LENGTH))
            }
        }
    }
    /**
     * @dev Returns a 256 bit word from 'extra' calldata, at some offset from the expected end of the original calldata.
     *
     * This function returns bogus data if no signature is included.
     */
    function _decodeExtraCalldataWord(uint256 offset) private pure returns (bytes32 result) {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            result := calldataload(add(sub(calldatasize(), _EXTRA_CALLDATA_LENGTH), offset))
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
// Based on the ReentrancyGuard library from OpenZeppelin contracts, altered to reduce bytecode size.
// Modifier code is inlined by the compiler, which causes its code to appear multiple times in the codebase. By using
// private functions, we achieve the same end result with slightly higher runtime gas costs but reduced bytecode size.
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor() {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _enterNonReentrant();
        _;
        _exitNonReentrant();
    }
    function _enterNonReentrant() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        _require(_status != _ENTERED, Errors.REENTRANCY);
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }
    function _exitNonReentrant() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma experimental ABIEncoderV2;
import "../../lib/openzeppelin/IERC20.sol";
import "./IWETH.sol";
import "./IAsset.sol";
import "./IAuthorizer.sol";
import "./IFlashLoanRecipient.sol";
import "../ProtocolFeesCollector.sol";
import "../../lib/helpers/ISignaturesValidator.sol";
import "../../lib/helpers/ITemporarilyPausable.sol";
pragma solidity ^0.7.0;
/**
 * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
 * don't override one of these declarations.
 */
interface IVault is ISignaturesValidator, ITemporarilyPausable {
    // Generalities about the Vault:
    //
    // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
    // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
    // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
    // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
    // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
    //
    // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
    // while execution control is transferred to a token contract during a swap) will result in a revert. View
    // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
    // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
    //
    // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.
    // Authorizer
    //
    // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
    // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
    // can perform a given action.
    /**
     * @dev Returns the Vault's Authorizer.
     */
    function getAuthorizer() external view returns (IAuthorizer);
    /**
     * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
     *
     * Emits an `AuthorizerChanged` event.
     */
    function setAuthorizer(IAuthorizer newAuthorizer) external;
    /**
     * @dev Emitted when a new authorizer is set by `setAuthorizer`.
     */
    event AuthorizerChanged(IAuthorizer indexed newAuthorizer);
    // Relayers
    //
    // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
    // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
    // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
    // this power, two things must occur:
    //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
    //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
    //    functions.
    //  - Each user must approve the relayer to act on their behalf.
    // This double protection means users cannot be tricked into approving malicious relayers (because they will not
    // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
    // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.
    /**
     * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
     */
    function hasApprovedRelayer(address user, address relayer) external view returns (bool);
    /**
     * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
     *
     * Emits a `RelayerApprovalChanged` event.
     */
    function setRelayerApproval(
        address sender,
        address relayer,
        bool approved
    ) external;
    /**
     * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
     */
    event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);
    // Internal Balance
    //
    // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
    // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
    // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
    // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
    //
    // Internal Balance management features batching, which means a single contract call can be used to perform multiple
    // operations of different kinds, with different senders and recipients, at once.
    /**
     * @dev Returns `user`'s Internal Balance for a set of tokens.
     */
    function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);
    /**
     * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
     * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
     * it lets integrators reuse a user's Vault allowance.
     *
     * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
     */
    function manageUserBalance(UserBalanceOp[] memory ops) external payable;
    /**
     * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
     without manual WETH wrapping or unwrapping.
     */
    struct UserBalanceOp {
        UserBalanceOpKind kind;
        IAsset asset;
        uint256 amount;
        address sender;
        address payable recipient;
    }
    // There are four possible operations in `manageUserBalance`:
    //
    // - DEPOSIT_INTERNAL
    // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
    // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
    //
    // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
    // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
    // relevant for relayers).
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - WITHDRAW_INTERNAL
    // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
    //
    // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
    // it to the recipient as ETH.
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - TRANSFER_INTERNAL
    // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
    //
    // Reverts if the ETH sentinel value is passed.
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - TRANSFER_EXTERNAL
    // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
    // relayers, as it lets them reuse a user's Vault allowance.
    //
    // Reverts if the ETH sentinel value is passed.
    //
    // Emits an `ExternalBalanceTransfer` event.
    enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }
    /**
     * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
     * interacting with Pools using Internal Balance.
     *
     * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
     * address.
     */
    event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);
    /**
     * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
     */
    event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);
    // Pools
    //
    // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
    // functionality:
    //
    //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
    // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
    // which increase with the number of registered tokens.
    //
    //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
    // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
    // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
    // independent of the number of registered tokens.
    //
    //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
    // minimal swap info Pools, these are called via IMinimalSwapInfoPool.
    enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }
    /**
     * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
     * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
     * changed.
     *
     * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
     * depending on the chosen specialization setting. This contract is known as the Pool's contract.
     *
     * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
     * multiple Pools may share the same contract.
     *
     * Emits a `PoolRegistered` event.
     */
    function registerPool(PoolSpecialization specialization) external returns (bytes32);
    /**
     * @dev Emitted when a Pool is registered by calling `registerPool`.
     */
    event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);
    /**
     * @dev Returns a Pool's contract address and specialization setting.
     */
    function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);
    /**
     * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
     *
     * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
     * exit by receiving registered tokens, and can only swap registered tokens.
     *
     * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
     * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
     * ascending order.
     *
     * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
     * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
     * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
     * expected to be highly secured smart contracts with sound design principles, and the decision to register an
     * Asset Manager should not be made lightly.
     *
     * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
     * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
     * different Asset Manager.
     *
     * Emits a `TokensRegistered` event.
     */
    function registerTokens(
        bytes32 poolId,
        IERC20[] memory tokens,
        address[] memory assetManagers
    ) external;
    /**
     * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
     */
    event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);
    /**
     * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
     *
     * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
     * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
     * must be deregistered in the same `deregisterTokens` call.
     *
     * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
     *
     * Emits a `TokensDeregistered` event.
     */
    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;
    /**
     * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
     */
    event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);
    /**
     * @dev Returns detailed information for a Pool's registered token.
     *
     * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
     * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
     * equals the sum of `cash` and `managed`.
     *
     * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
     * `managed` or `total` balance to be greater than 2^112 - 1.
     *
     * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
     * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
     * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
     * change for this purpose, and will update `lastChangeBlock`.
     *
     * `assetManager` is the Pool's token Asset Manager.
     */
    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
        external
        view
        returns (
            uint256 cash,
            uint256 managed,
            uint256 lastChangeBlock,
            address assetManager
        );
    /**
     * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
     * the tokens' `balances` changed.
     *
     * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
     * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
     *
     * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
     * order as passed to `registerTokens`.
     *
     * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
     * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
     * instead.
     */
    function getPoolTokens(bytes32 poolId)
        external
        view
        returns (
            IERC20[] memory tokens,
            uint256[] memory balances,
            uint256 lastChangeBlock
        );
    /**
     * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
     * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
     * Pool shares.
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
     * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
     * these maximums.
     *
     * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
     * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
     * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
     * back to the caller (not the sender, which is important for relayers).
     *
     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
     * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
     * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
     * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
     *
     * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
     * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
     * withdrawn from Internal Balance: attempting to do so will trigger a revert.
     *
     * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
     * their own custom logic. This typically requires additional information from the user (such as the expected number
     * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
     * directly to the Pool's contract, as is `recipient`.
     *
     * Emits a `PoolBalanceChanged` event.
     */
    function joinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        JoinPoolRequest memory request
    ) external payable;
    struct JoinPoolRequest {
        IAsset[] assets;
        uint256[] maxAmountsIn;
        bytes userData;
        bool fromInternalBalance;
    }
    /**
     * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
     * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
     * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
     * `getPoolTokenInfo`).
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
     * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
     * it just enforces these minimums.
     *
     * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
     * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
     * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
     *
     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
     * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
     * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
     * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
     *
     * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
     * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
     * do so will trigger a revert.
     *
     * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
     * `tokens` array. This array must match the Pool's registered tokens.
     *
     * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
     * their own custom logic. This typically requires additional information from the user (such as the expected number
     * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
     * passed directly to the Pool's contract.
     *
     * Emits a `PoolBalanceChanged` event.
     */
    function exitPool(
        bytes32 poolId,
        address sender,
        address payable recipient,
        ExitPoolRequest memory request
    ) external;
    struct ExitPoolRequest {
        IAsset[] assets;
        uint256[] minAmountsOut;
        bytes userData;
        bool toInternalBalance;
    }
    /**
     * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
     */
    event PoolBalanceChanged(
        bytes32 indexed poolId,
        address indexed liquidityProvider,
        IERC20[] tokens,
        int256[] deltas,
        uint256[] protocolFeeAmounts
    );
    enum PoolBalanceChangeKind { JOIN, EXIT }
    // Swaps
    //
    // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
    // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
    // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
    //
    // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
    // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
    // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
    // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
    // individual swaps.
    //
    // There are two swap kinds:
    //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
    // `onSwap` hook) the amount of tokens out (to send to the recipient).
    //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
    // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
    //
    // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
    // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
    // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
    // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
    // the final intended token.
    //
    // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
    // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
    // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
    // much less gas than they would otherwise.
    //
    // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
    // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
    // updating the Pool's internal accounting).
    //
    // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
    // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
    // minimum amount of tokens to receive (by passing a negative value) is specified.
    //
    // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
    // this point in time (e.g. if the transaction failed to be included in a block promptly).
    //
    // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
    // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
    // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
    // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
    //
    // Finally, Internal Balance can be used when either sending or receiving tokens.
    enum SwapKind { GIVEN_IN, GIVEN_OUT }
    /**
     * @dev Performs a swap with a single Pool.
     *
     * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
     * taken from the Pool, which must be greater than or equal to `limit`.
     *
     * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
     * sent to the Pool, which must be less than or equal to `limit`.
     *
     * Internal Balance usage and the recipient are determined by the `funds` struct.
     *
     * Emits a `Swap` event.
     */
    function swap(
        SingleSwap memory singleSwap,
        FundManagement memory funds,
        uint256 limit,
        uint256 deadline
    ) external payable returns (uint256);
    /**
     * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
     * the `kind` value.
     *
     * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
     * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
     *
     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
     * used to extend swap behavior.
     */
    struct SingleSwap {
        bytes32 poolId;
        SwapKind kind;
        IAsset assetIn;
        IAsset assetOut;
        uint256 amount;
        bytes userData;
    }
    /**
     * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
     * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
     *
     * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
     * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
     * the same index in the `assets` array.
     *
     * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
     * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
     * `amountOut` depending on the swap kind.
     *
     * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
     * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
     * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
     *
     * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
     * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
     * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
     * or unwrapped from WETH by the Vault.
     *
     * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
     * the minimum or maximum amount of each token the vault is allowed to transfer.
     *
     * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
     * equivalent `swap` call.
     *
     * Emits `Swap` events.
     */
    function batchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds,
        int256[] memory limits,
        uint256 deadline
    ) external payable returns (int256[] memory);
    /**
     * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
     * `assets` array passed to that function, and ETH assets are converted to WETH.
     *
     * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
     * from the previous swap, depending on the swap kind.
     *
     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
     * used to extend swap behavior.
     */
    struct BatchSwapStep {
        bytes32 poolId;
        uint256 assetInIndex;
        uint256 assetOutIndex;
        uint256 amount;
        bytes userData;
    }
    /**
     * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
     */
    event Swap(
        bytes32 indexed poolId,
        IERC20 indexed tokenIn,
        IERC20 indexed tokenOut,
        uint256 amountIn,
        uint256 amountOut
    );
    /**
     * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
     * `recipient` account.
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
     * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
     * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
     * `joinPool`.
     *
     * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
     * transferred. This matches the behavior of `exitPool`.
     *
     * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
     * revert.
     */
    struct FundManagement {
        address sender;
        bool fromInternalBalance;
        address payable recipient;
        bool toInternalBalance;
    }
    /**
     * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
     * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
     *
     * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
     * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
     * receives are the same that an equivalent `batchSwap` call would receive.
     *
     * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
     * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
     * approve them for the Vault, or even know a user's address.
     *
     * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
     * eth_call instead of eth_sendTransaction.
     */
    function queryBatchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds
    ) external returns (int256[] memory assetDeltas);
    // Flash Loans
    /**
     * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
     * and then reverting unless the tokens plus a proportional protocol fee have been returned.
     *
     * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
     * for each token contract. `tokens` must be sorted in ascending order.
     *
     * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
     * `receiveFlashLoan` call.
     *
     * Emits `FlashLoan` events.
     */
    function flashLoan(
        IFlashLoanRecipient recipient,
        IERC20[] memory tokens,
        uint256[] memory amounts,
        bytes memory userData
    ) external;
    /**
     * @dev Emitted for each individual flash loan performed by `flashLoan`.
     */
    event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);
    // Asset Management
    //
    // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
    // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
    // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
    // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
    // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
    // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
    //
    // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
    // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
    //
    // This concept is unrelated to the IAsset interface.
    /**
     * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
     *
     * Pool Balance management features batching, which means a single contract call can be used to perform multiple
     * operations of different kinds, with different Pools and tokens, at once.
     *
     * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
     */
    function managePoolBalance(PoolBalanceOp[] memory ops) external;
    struct PoolBalanceOp {
        PoolBalanceOpKind kind;
        bytes32 poolId;
        IERC20 token;
        uint256 amount;
    }
    /**
     * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
     *
     * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
     *
     * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
     * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
     */
    enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }
    /**
     * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
     */
    event PoolBalanceManaged(
        bytes32 indexed poolId,
        address indexed assetManager,
        IERC20 indexed token,
        int256 cashDelta,
        int256 managedDelta
    );
    // Protocol Fees
    //
    // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
    // permissioned accounts.
    //
    // There are two kinds of protocol fees:
    //
    //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
    //
    //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
    // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
    // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
    // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
    // exiting a Pool in debt without first paying their share.
    /**
     * @dev Returns the current protocol fee module.
     */
    function getProtocolFeesCollector() external view returns (ProtocolFeesCollector);
    /**
     * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
     * error in some part of the system.
     *
     * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
     *
     * While the contract is paused, the following features are disabled:
     * - depositing and transferring internal balance
     * - transferring external balance (using the Vault's allowance)
     * - swaps
     * - joining Pools
     * - Asset Manager interactions
     *
     * Internal Balance can still be withdrawn, and Pools exited.
     */
    function setPaused(bool paused) external;
    /**
     * @dev Returns the Vault's WETH instance.
     */
    function WETH() external view returns (IWETH);
    // solhint-disable-previous-line func-name-mixedcase
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
interface IAuthentication {
    /**
     * @dev Returns the action identifier associated with the external function described by `selector`.
     */
    function getActionId(bytes4 selector) external view returns (bytes32);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev Interface for the TemporarilyPausable helper.
 */
interface ITemporarilyPausable {
    /**
     * @dev Emitted every time the pause state changes by `_setPaused`.
     */
    event PausedStateChanged(bool paused);
    /**
     * @dev Returns the current paused state.
     */
    function getPausedState()
        external
        view
        returns (
            bool paused,
            uint256 pauseWindowEndTime,
            uint256 bufferPeriodEndTime
        );
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
 */
interface ISignaturesValidator {
    /**
     * @dev Returns the EIP712 domain separator.
     */
    function getDomainSeparator() external view returns (bytes32);
    /**
     * @dev Returns the next nonce used by an address to sign messages.
     */
    function getNextNonce(address user) external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;
    /* solhint-enable var-name-mixedcase */
    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        _HASHED_NAME = keccak256(bytes(name));
        _HASHED_VERSION = keccak256(bytes(version));
        _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
    }
    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view virtual returns (bytes32) {
        return keccak256(abi.encode(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION, _getChainId(), address(this)));
    }
    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return keccak256(abi.encodePacked("\\x19\\x01", _domainSeparatorV4(), structHash));
    }
    function _getChainId() private view returns (uint256 chainId) {
        // Silence state mutability warning without generating bytecode.
        // See https://github.com/ethereum/solidity/issues/10090#issuecomment-741789128 and
        // https://github.com/ethereum/solidity/issues/2691
        this;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            chainId := chainid()
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
 * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
 * types.
 *
 * This concept is unrelated to a Pool's Asset Managers.
 */
interface IAsset {
    // solhint-disable-previous-line no-empty-blocks
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
// Inspired by Aave Protocol's IFlashLoanReceiver.
import "../../lib/openzeppelin/IERC20.sol";
interface IFlashLoanRecipient {
    /**
     * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
     *
     * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
     * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
     * Vault, or else the entire flash loan will revert.
     *
     * `userData` is the same value passed in the `IVault.flashLoan` call.
     */
    function receiveFlashLoan(
        IERC20[] memory tokens,
        uint256[] memory amounts,
        uint256[] memory feeAmounts,
        bytes memory userData
    ) external;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/openzeppelin/IERC20.sol";
import "../lib/helpers/InputHelpers.sol";
import "../lib/helpers/Authentication.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "./interfaces/IVault.sol";
import "./interfaces/IAuthorizer.sol";
/**
 * @dev This an auxiliary contract to the Vault, deployed by it during construction. It offloads some of the tasks the
 * Vault performs to reduce its overall bytecode size.
 *
 * The current values for all protocol fee percentages are stored here, and any tokens charged as protocol fees are
 * sent to this contract, where they may be withdrawn by authorized entities. All authorization tasks are delegated
 * to the Vault's own authorizer.
 */
contract ProtocolFeesCollector is Authentication, ReentrancyGuard {
    using SafeERC20 for IERC20;
    // Absolute maximum fee percentages (1e18 = 100%, 1e16 = 1%).
    uint256 private constant _MAX_PROTOCOL_SWAP_FEE_PERCENTAGE = 50e16; // 50%
    uint256 private constant _MAX_PROTOCOL_FLASH_LOAN_FEE_PERCENTAGE = 1e16; // 1%
    IVault public immutable vault;
    // All fee percentages are 18-decimal fixed point numbers.
    // The swap fee is charged whenever a swap occurs, as a percentage of the fee charged by the Pool. These are not
    // actually charged on each individual swap: the `Vault` relies on the Pools being honest and reporting fees due
    // when users join and exit them.
    uint256 private _swapFeePercentage;
    // The flash loan fee is charged whenever a flash loan occurs, as a percentage of the tokens lent.
    uint256 private _flashLoanFeePercentage;
    event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
    event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);
    constructor(IVault _vault)
        // The ProtocolFeesCollector is a singleton, so it simply uses its own address to disambiguate action
        // identifiers.
        Authentication(bytes32(uint256(address(this))))
    {
        vault = _vault;
    }
    function withdrawCollectedFees(
        IERC20[] calldata tokens,
        uint256[] calldata amounts,
        address recipient
    ) external nonReentrant authenticate {
        InputHelpers.ensureInputLengthMatch(tokens.length, amounts.length);
        for (uint256 i = 0; i < tokens.length; ++i) {
            IERC20 token = tokens[i];
            uint256 amount = amounts[i];
            token.safeTransfer(recipient, amount);
        }
    }
    function setSwapFeePercentage(uint256 newSwapFeePercentage) external authenticate {
        _require(newSwapFeePercentage <= _MAX_PROTOCOL_SWAP_FEE_PERCENTAGE, Errors.SWAP_FEE_PERCENTAGE_TOO_HIGH);
        _swapFeePercentage = newSwapFeePercentage;
        emit SwapFeePercentageChanged(newSwapFeePercentage);
    }
    function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external authenticate {
        _require(
            newFlashLoanFeePercentage <= _MAX_PROTOCOL_FLASH_LOAN_FEE_PERCENTAGE,
            Errors.FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH
        );
        _flashLoanFeePercentage = newFlashLoanFeePercentage;
        emit FlashLoanFeePercentageChanged(newFlashLoanFeePercentage);
    }
    function getSwapFeePercentage() external view returns (uint256) {
        return _swapFeePercentage;
    }
    function getFlashLoanFeePercentage() external view returns (uint256) {
        return _flashLoanFeePercentage;
    }
    function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts) {
        feeAmounts = new uint256[](tokens.length);
        for (uint256 i = 0; i < tokens.length; ++i) {
            feeAmounts[i] = tokens[i].balanceOf(address(this));
        }
    }
    function getAuthorizer() external view returns (IAuthorizer) {
        return _getAuthorizer();
    }
    function _canPerform(bytes32 actionId, address account) internal view override returns (bool) {
        return _getAuthorizer().canPerform(actionId, account, address(this));
    }
    function _getAuthorizer() internal view returns (IAuthorizer) {
        return vault.getAuthorizer();
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../openzeppelin/IERC20.sol";
import "./BalancerErrors.sol";
import "../../vault/interfaces/IAsset.sol";
library InputHelpers {
    function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
        _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
    }
    function ensureInputLengthMatch(
        uint256 a,
        uint256 b,
        uint256 c
    ) internal pure {
        _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
    }
    function ensureArrayIsSorted(IAsset[] memory array) internal pure {
        address[] memory addressArray;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            addressArray := array
        }
        ensureArrayIsSorted(addressArray);
    }
    function ensureArrayIsSorted(IERC20[] memory array) internal pure {
        address[] memory addressArray;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            addressArray := array
        }
        ensureArrayIsSorted(addressArray);
    }
    function ensureArrayIsSorted(address[] memory array) internal pure {
        if (array.length < 2) {
            return;
        }
        address previous = array[0];
        for (uint256 i = 1; i < array.length; ++i) {
            address current = array[i];
            _require(previous < current, Errors.UNSORTED_ARRAY);
            previous = current;
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
import "./IERC20.sol";
/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(address(token), abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(address(token), abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     *
     * WARNING: `token` is assumed to be a contract: calls to EOAs will *not* revert.
     */
    function _callOptionalReturn(address token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves.
        (bool success, bytes memory returndata) = token.call(data);
        // If the low-level call didn't succeed we return whatever was returned from it.
        assembly {
            if eq(success, 0) {
                returndatacopy(0, 0, returndatasize())
                revert(0, returndatasize())
            }
        }
        // Finally we check the returndata size is either zero or true - note that this check will always pass for EOAs
        _require(returndata.length == 0 || abi.decode(returndata, (bool)), Errors.SAFE_ERC20_CALL_FAILED);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/math/FixedPoint.sol";
import "../lib/helpers/BalancerErrors.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "./ProtocolFeesCollector.sol";
import "./VaultAuthorization.sol";
import "./interfaces/IVault.sol";
/**
 * @dev To reduce the bytecode size of the Vault, most of the protocol fee logic is not here, but in the
 * ProtocolFeesCollector contract.
 */
abstract contract Fees is IVault {
    using SafeERC20 for IERC20;
    ProtocolFeesCollector private immutable _protocolFeesCollector;
    constructor() {
        _protocolFeesCollector = new ProtocolFeesCollector(IVault(this));
    }
    function getProtocolFeesCollector() public view override returns (ProtocolFeesCollector) {
        return _protocolFeesCollector;
    }
    /**
     * @dev Returns the protocol swap fee percentage.
     */
    function _getProtocolSwapFeePercentage() internal view returns (uint256) {
        return getProtocolFeesCollector().getSwapFeePercentage();
    }
    /**
     * @dev Returns the protocol fee amount to charge for a flash loan of `amount`.
     */
    function _calculateFlashLoanFeeAmount(uint256 amount) internal view returns (uint256) {
        // Fixed point multiplication introduces error: we round up, which means in certain scenarios the charged
        // percentage can be slightly higher than intended.
        uint256 percentage = getProtocolFeesCollector().getFlashLoanFeePercentage();
        return FixedPoint.mulUp(amount, percentage);
    }
    function _payFeeAmount(IERC20 token, uint256 amount) internal {
        if (amount > 0) {
            token.safeTransfer(address(getProtocolFeesCollector()), amount);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "./LogExpMath.sol";
import "../helpers/BalancerErrors.sol";
/* solhint-disable private-vars-leading-underscore */
library FixedPoint {
    uint256 internal constant ONE = 1e18; // 18 decimal places
    uint256 internal constant MAX_POW_RELATIVE_ERROR = 10000; // 10^(-14)
    // Minimum base for the power function when the exponent is 'free' (larger than ONE).
    uint256 internal constant MIN_POW_BASE_FREE_EXPONENT = 0.7e18;
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        // Fixed Point addition is the same as regular checked addition
        uint256 c = a + b;
        _require(c >= a, Errors.ADD_OVERFLOW);
        return c;
    }
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        // Fixed Point addition is the same as regular checked addition
        _require(b <= a, Errors.SUB_OVERFLOW);
        uint256 c = a - b;
        return c;
    }
    function mulDown(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 product = a * b;
        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
        return product / ONE;
    }
    function mulUp(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 product = a * b;
        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
        if (product == 0) {
            return 0;
        } else {
            // The traditional divUp formula is:
            // divUp(x, y) := (x + y - 1) / y
            // To avoid intermediate overflow in the addition, we distribute the division and get:
            // divUp(x, y) := (x - 1) / y + 1
            // Note that this requires x != 0, which we already tested for.
            return ((product - 1) / ONE) + 1;
        }
    }
    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        if (a == 0) {
            return 0;
        } else {
            uint256 aInflated = a * ONE;
            _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
            return aInflated / b;
        }
    }
    function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        if (a == 0) {
            return 0;
        } else {
            uint256 aInflated = a * ONE;
            _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
            // The traditional divUp formula is:
            // divUp(x, y) := (x + y - 1) / y
            // To avoid intermediate overflow in the addition, we distribute the division and get:
            // divUp(x, y) := (x - 1) / y + 1
            // Note that this requires x != 0, which we already tested for.
            return ((aInflated - 1) / b) + 1;
        }
    }
    /**
     * @dev Returns x^y, assuming both are fixed point numbers, rounding down. The result is guaranteed to not be above
     * the true value (that is, the error function expected - actual is always positive).
     */
    function powDown(uint256 x, uint256 y) internal pure returns (uint256) {
        uint256 raw = LogExpMath.pow(x, y);
        uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
        if (raw < maxError) {
            return 0;
        } else {
            return sub(raw, maxError);
        }
    }
    /**
     * @dev Returns x^y, assuming both are fixed point numbers, rounding up. The result is guaranteed to not be below
     * the true value (that is, the error function expected - actual is always negative).
     */
    function powUp(uint256 x, uint256 y) internal pure returns (uint256) {
        uint256 raw = LogExpMath.pow(x, y);
        uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
        return add(raw, maxError);
    }
    /**
     * @dev Returns the complement of a value (1 - x), capped to 0 if x is larger than 1.
     *
     * Useful when computing the complement for values with some level of relative error, as it strips this error and
     * prevents intermediate negative values.
     */
    function complement(uint256 x) internal pure returns (uint256) {
        return (x < ONE) ? (ONE - x) : 0;
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General internal License for more details.
// You should have received a copy of the GNU General internal License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
/* solhint-disable */
/**
 * @dev Exponentiation and logarithm functions for 18 decimal fixed point numbers (both base and exponent/argument).
 *
 * Exponentiation and logarithm with arbitrary bases (x^y and log_x(y)) are implemented by conversion to natural
 * exponentiation and logarithm (where the base is Euler's number).
 *
 * @author Fernando Martinelli - @fernandomartinelli
 * @author Sergio Yuhjtman - @sergioyuhjtman
 * @author Daniel Fernandez - @dmf7z
 */
library LogExpMath {
    // All fixed point multiplications and divisions are inlined. This means we need to divide by ONE when multiplying
    // two numbers, and multiply by ONE when dividing them.
    // All arguments and return values are 18 decimal fixed point numbers.
    int256 constant ONE_18 = 1e18;
    // Internally, intermediate values are computed with higher precision as 20 decimal fixed point numbers, and in the
    // case of ln36, 36 decimals.
    int256 constant ONE_20 = 1e20;
    int256 constant ONE_36 = 1e36;
    // The domain of natural exponentiation is bound by the word size and number of decimals used.
    //
    // Because internally the result will be stored using 20 decimals, the largest possible result is
    // (2^255 - 1) / 10^20, which makes the largest exponent ln((2^255 - 1) / 10^20) = 130.700829182905140221.
    // The smallest possible result is 10^(-18), which makes largest negative argument
    // ln(10^(-18)) = -41.446531673892822312.
    // We use 130.0 and -41.0 to have some safety margin.
    int256 constant MAX_NATURAL_EXPONENT = 130e18;
    int256 constant MIN_NATURAL_EXPONENT = -41e18;
    // Bounds for ln_36's argument. Both ln(0.9) and ln(1.1) can be represented with 36 decimal places in a fixed point
    // 256 bit integer.
    int256 constant LN_36_LOWER_BOUND = ONE_18 - 1e17;
    int256 constant LN_36_UPPER_BOUND = ONE_18 + 1e17;
    uint256 constant MILD_EXPONENT_BOUND = 2**254 / uint256(ONE_20);
    // 18 decimal constants
    int256 constant x0 = 128000000000000000000; // 2ˆ7
    int256 constant a0 = 38877084059945950922200000000000000000000000000000000000; // eˆ(x0) (no decimals)
    int256 constant x1 = 64000000000000000000; // 2ˆ6
    int256 constant a1 = 6235149080811616882910000000; // eˆ(x1) (no decimals)
    // 20 decimal constants
    int256 constant x2 = 3200000000000000000000; // 2ˆ5
    int256 constant a2 = 7896296018268069516100000000000000; // eˆ(x2)
    int256 constant x3 = 1600000000000000000000; // 2ˆ4
    int256 constant a3 = 888611052050787263676000000; // eˆ(x3)
    int256 constant x4 = 800000000000000000000; // 2ˆ3
    int256 constant a4 = 298095798704172827474000; // eˆ(x4)
    int256 constant x5 = 400000000000000000000; // 2ˆ2
    int256 constant a5 = 5459815003314423907810; // eˆ(x5)
    int256 constant x6 = 200000000000000000000; // 2ˆ1
    int256 constant a6 = 738905609893065022723; // eˆ(x6)
    int256 constant x7 = 100000000000000000000; // 2ˆ0
    int256 constant a7 = 271828182845904523536; // eˆ(x7)
    int256 constant x8 = 50000000000000000000; // 2ˆ-1
    int256 constant a8 = 164872127070012814685; // eˆ(x8)
    int256 constant x9 = 25000000000000000000; // 2ˆ-2
    int256 constant a9 = 128402541668774148407; // eˆ(x9)
    int256 constant x10 = 12500000000000000000; // 2ˆ-3
    int256 constant a10 = 113314845306682631683; // eˆ(x10)
    int256 constant x11 = 6250000000000000000; // 2ˆ-4
    int256 constant a11 = 106449445891785942956; // eˆ(x11)
    /**
     * @dev Exponentiation (x^y) with unsigned 18 decimal fixed point base and exponent.
     *
     * Reverts if ln(x) * y is smaller than `MIN_NATURAL_EXPONENT`, or larger than `MAX_NATURAL_EXPONENT`.
     */
    function pow(uint256 x, uint256 y) internal pure returns (uint256) {
        if (y == 0) {
            // We solve the 0^0 indetermination by making it equal one.
            return uint256(ONE_18);
        }
        if (x == 0) {
            return 0;
        }
        // Instead of computing x^y directly, we instead rely on the properties of logarithms and exponentiation to
        // arrive at that result. In particular, exp(ln(x)) = x, and ln(x^y) = y * ln(x). This means
        // x^y = exp(y * ln(x)).
        // The ln function takes a signed value, so we need to make sure x fits in the signed 256 bit range.
        _require(x < 2**255, Errors.X_OUT_OF_BOUNDS);
        int256 x_int256 = int256(x);
        // We will compute y * ln(x) in a single step. Depending on the value of x, we can either use ln or ln_36. In
        // both cases, we leave the division by ONE_18 (due to fixed point multiplication) to the end.
        // This prevents y * ln(x) from overflowing, and at the same time guarantees y fits in the signed 256 bit range.
        _require(y < MILD_EXPONENT_BOUND, Errors.Y_OUT_OF_BOUNDS);
        int256 y_int256 = int256(y);
        int256 logx_times_y;
        if (LN_36_LOWER_BOUND < x_int256 && x_int256 < LN_36_UPPER_BOUND) {
            int256 ln_36_x = ln_36(x_int256);
            // ln_36_x has 36 decimal places, so multiplying by y_int256 isn't as straightforward, since we can't just
            // bring y_int256 to 36 decimal places, as it might overflow. Instead, we perform two 18 decimal
            // multiplications and add the results: one with the first 18 decimals of ln_36_x, and one with the
            // (downscaled) last 18 decimals.
            logx_times_y = ((ln_36_x / ONE_18) * y_int256 + ((ln_36_x % ONE_18) * y_int256) / ONE_18);
        } else {
            logx_times_y = ln(x_int256) * y_int256;
        }
        logx_times_y /= ONE_18;
        // Finally, we compute exp(y * ln(x)) to arrive at x^y
        _require(
            MIN_NATURAL_EXPONENT <= logx_times_y && logx_times_y <= MAX_NATURAL_EXPONENT,
            Errors.PRODUCT_OUT_OF_BOUNDS
        );
        return uint256(exp(logx_times_y));
    }
    /**
     * @dev Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
     *
     * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
     */
    function exp(int256 x) internal pure returns (int256) {
        _require(x >= MIN_NATURAL_EXPONENT && x <= MAX_NATURAL_EXPONENT, Errors.INVALID_EXPONENT);
        if (x < 0) {
            // We only handle positive exponents: e^(-x) is computed as 1 / e^x. We can safely make x positive since it
            // fits in the signed 256 bit range (as it is larger than MIN_NATURAL_EXPONENT).
            // Fixed point division requires multiplying by ONE_18.
            return ((ONE_18 * ONE_18) / exp(-x));
        }
        // First, we use the fact that e^(x+y) = e^x * e^y to decompose x into a sum of powers of two, which we call x_n,
        // where x_n == 2^(7 - n), and e^x_n = a_n has been precomputed. We choose the first x_n, x0, to equal 2^7
        // because all larger powers are larger than MAX_NATURAL_EXPONENT, and therefore not present in the
        // decomposition.
        // At the end of this process we will have the product of all e^x_n = a_n that apply, and the remainder of this
        // decomposition, which will be lower than the smallest x_n.
        // exp(x) = k_0 * a_0 * k_1 * a_1 * ... + k_n * a_n * exp(remainder), where each k_n equals either 0 or 1.
        // We mutate x by subtracting x_n, making it the remainder of the decomposition.
        // The first two a_n (e^(2^7) and e^(2^6)) are too large if stored as 18 decimal numbers, and could cause
        // intermediate overflows. Instead we store them as plain integers, with 0 decimals.
        // Additionally, x0 + x1 is larger than MAX_NATURAL_EXPONENT, which means they will not both be present in the
        // decomposition.
        // For each x_n, we test if that term is present in the decomposition (if x is larger than it), and if so deduct
        // it and compute the accumulated product.
        int256 firstAN;
        if (x >= x0) {
            x -= x0;
            firstAN = a0;
        } else if (x >= x1) {
            x -= x1;
            firstAN = a1;
        } else {
            firstAN = 1; // One with no decimal places
        }
        // We now transform x into a 20 decimal fixed point number, to have enhanced precision when computing the
        // smaller terms.
        x *= 100;
        // `product` is the accumulated product of all a_n (except a0 and a1), which starts at 20 decimal fixed point
        // one. Recall that fixed point multiplication requires dividing by ONE_20.
        int256 product = ONE_20;
        if (x >= x2) {
            x -= x2;
            product = (product * a2) / ONE_20;
        }
        if (x >= x3) {
            x -= x3;
            product = (product * a3) / ONE_20;
        }
        if (x >= x4) {
            x -= x4;
            product = (product * a4) / ONE_20;
        }
        if (x >= x5) {
            x -= x5;
            product = (product * a5) / ONE_20;
        }
        if (x >= x6) {
            x -= x6;
            product = (product * a6) / ONE_20;
        }
        if (x >= x7) {
            x -= x7;
            product = (product * a7) / ONE_20;
        }
        if (x >= x8) {
            x -= x8;
            product = (product * a8) / ONE_20;
        }
        if (x >= x9) {
            x -= x9;
            product = (product * a9) / ONE_20;
        }
        // x10 and x11 are unnecessary here since we have high enough precision already.
        // Now we need to compute e^x, where x is small (in particular, it is smaller than x9). We use the Taylor series
        // expansion for e^x: 1 + x + (x^2 / 2!) + (x^3 / 3!) + ... + (x^n / n!).
        int256 seriesSum = ONE_20; // The initial one in the sum, with 20 decimal places.
        int256 term; // Each term in the sum, where the nth term is (x^n / n!).
        // The first term is simply x.
        term = x;
        seriesSum += term;
        // Each term (x^n / n!) equals the previous one times x, divided by n. Since x is a fixed point number,
        // multiplying by it requires dividing by ONE_20, but dividing by the non-fixed point n values does not.
        term = ((term * x) / ONE_20) / 2;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 3;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 4;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 5;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 6;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 7;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 8;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 9;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 10;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 11;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 12;
        seriesSum += term;
        // 12 Taylor terms are sufficient for 18 decimal precision.
        // We now have the first a_n (with no decimals), and the product of all other a_n present, and the Taylor
        // approximation of the exponentiation of the remainder (both with 20 decimals). All that remains is to multiply
        // all three (one 20 decimal fixed point multiplication, dividing by ONE_20, and one integer multiplication),
        // and then drop two digits to return an 18 decimal value.
        return (((product * seriesSum) / ONE_20) * firstAN) / 100;
    }
    /**
     * @dev Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
     */
    function ln(int256 a) internal pure returns (int256) {
        // The real natural logarithm is not defined for negative numbers or zero.
        _require(a > 0, Errors.OUT_OF_BOUNDS);
        if (a < ONE_18) {
            // Since ln(a^k) = k * ln(a), we can compute ln(a) as ln(a) = ln((1/a)^(-1)) = - ln((1/a)). If a is less
            // than one, 1/a will be greater than one, and this if statement will not be entered in the recursive call.
            // Fixed point division requires multiplying by ONE_18.
            return (-ln((ONE_18 * ONE_18) / a));
        }
        // First, we use the fact that ln^(a * b) = ln(a) + ln(b) to decompose ln(a) into a sum of powers of two, which
        // we call x_n, where x_n == 2^(7 - n), which are the natural logarithm of precomputed quantities a_n (that is,
        // ln(a_n) = x_n). We choose the first x_n, x0, to equal 2^7 because the exponential of all larger powers cannot
        // be represented as 18 fixed point decimal numbers in 256 bits, and are therefore larger than a.
        // At the end of this process we will have the sum of all x_n = ln(a_n) that apply, and the remainder of this
        // decomposition, which will be lower than the smallest a_n.
        // ln(a) = k_0 * x_0 + k_1 * x_1 + ... + k_n * x_n + ln(remainder), where each k_n equals either 0 or 1.
        // We mutate a by subtracting a_n, making it the remainder of the decomposition.
        // For reasons related to how `exp` works, the first two a_n (e^(2^7) and e^(2^6)) are not stored as fixed point
        // numbers with 18 decimals, but instead as plain integers with 0 decimals, so we need to multiply them by
        // ONE_18 to convert them to fixed point.
        // For each a_n, we test if that term is present in the decomposition (if a is larger than it), and if so divide
        // by it and compute the accumulated sum.
        int256 sum = 0;
        if (a >= a0 * ONE_18) {
            a /= a0; // Integer, not fixed point division
            sum += x0;
        }
        if (a >= a1 * ONE_18) {
            a /= a1; // Integer, not fixed point division
            sum += x1;
        }
        // All other a_n and x_n are stored as 20 digit fixed point numbers, so we convert the sum and a to this format.
        sum *= 100;
        a *= 100;
        // Because further a_n are  20 digit fixed point numbers, we multiply by ONE_20 when dividing by them.
        if (a >= a2) {
            a = (a * ONE_20) / a2;
            sum += x2;
        }
        if (a >= a3) {
            a = (a * ONE_20) / a3;
            sum += x3;
        }
        if (a >= a4) {
            a = (a * ONE_20) / a4;
            sum += x4;
        }
        if (a >= a5) {
            a = (a * ONE_20) / a5;
            sum += x5;
        }
        if (a >= a6) {
            a = (a * ONE_20) / a6;
            sum += x6;
        }
        if (a >= a7) {
            a = (a * ONE_20) / a7;
            sum += x7;
        }
        if (a >= a8) {
            a = (a * ONE_20) / a8;
            sum += x8;
        }
        if (a >= a9) {
            a = (a * ONE_20) / a9;
            sum += x9;
        }
        if (a >= a10) {
            a = (a * ONE_20) / a10;
            sum += x10;
        }
        if (a >= a11) {
            a = (a * ONE_20) / a11;
            sum += x11;
        }
        // a is now a small number (smaller than a_11, which roughly equals 1.06). This means we can use a Taylor series
        // that converges rapidly for values of `a` close to one - the same one used in ln_36.
        // Let z = (a - 1) / (a + 1).
        // ln(a) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
        // Recall that 20 digit fixed point division requires multiplying by ONE_20, and multiplication requires
        // division by ONE_20.
        int256 z = ((a - ONE_20) * ONE_20) / (a + ONE_20);
        int256 z_squared = (z * z) / ONE_20;
        // num is the numerator of the series: the z^(2 * n + 1) term
        int256 num = z;
        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
        int256 seriesSum = num;
        // In each step, the numerator is multiplied by z^2
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 3;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 5;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 7;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 9;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 11;
        // 6 Taylor terms are sufficient for 36 decimal precision.
        // Finally, we multiply by 2 (non fixed point) to compute ln(remainder)
        seriesSum *= 2;
        // We now have the sum of all x_n present, and the Taylor approximation of the logarithm of the remainder (both
        // with 20 decimals). All that remains is to sum these two, and then drop two digits to return a 18 decimal
        // value.
        return (sum + seriesSum) / 100;
    }
    /**
     * @dev Logarithm (log(arg, base), with signed 18 decimal fixed point base and argument argument.
     */
    function log(int256 arg, int256 base) internal pure returns (int256) {
        // This performs a simple base change: log(arg, base) = ln(arg) / ln(base).
        // Both logBase and logArg are computed as 36 decimal fixed point numbers, either by using ln_36, or by
        // upscaling.
        int256 logBase;
        if (LN_36_LOWER_BOUND < base && base < LN_36_UPPER_BOUND) {
            logBase = ln_36(base);
        } else {
            logBase = ln(base) * ONE_18;
        }
        int256 logArg;
        if (LN_36_LOWER_BOUND < arg && arg < LN_36_UPPER_BOUND) {
            logArg = ln_36(arg);
        } else {
            logArg = ln(arg) * ONE_18;
        }
        // When dividing, we multiply by ONE_18 to arrive at a result with 18 decimal places
        return (logArg * ONE_18) / logBase;
    }
    /**
     * @dev High precision (36 decimal places) natural logarithm (ln(x)) with signed 18 decimal fixed point argument,
     * for x close to one.
     *
     * Should only be used if x is between LN_36_LOWER_BOUND and LN_36_UPPER_BOUND.
     */
    function ln_36(int256 x) private pure returns (int256) {
        // Since ln(1) = 0, a value of x close to one will yield a very small result, which makes using 36 digits
        // worthwhile.
        // First, we transform x to a 36 digit fixed point value.
        x *= ONE_18;
        // We will use the following Taylor expansion, which converges very rapidly. Let z = (x - 1) / (x + 1).
        // ln(x) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
        // Recall that 36 digit fixed point division requires multiplying by ONE_36, and multiplication requires
        // division by ONE_36.
        int256 z = ((x - ONE_36) * ONE_36) / (x + ONE_36);
        int256 z_squared = (z * z) / ONE_36;
        // num is the numerator of the series: the z^(2 * n + 1) term
        int256 num = z;
        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
        int256 seriesSum = num;
        // In each step, the numerator is multiplied by z^2
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 3;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 5;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 7;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 9;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 11;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 13;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 15;
        // 8 Taylor terms are sufficient for 36 decimal precision.
        // All that remains is multiplying by 2 (non fixed point).
        return seriesSum * 2;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
 * Adapted from OpenZeppelin's SafeMath library
 */
library Math {
    /**
     * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        _require(c >= a, Errors.ADD_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the addition of two signed integers, reverting on overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b <= a, Errors.SUB_OVERFLOW);
        uint256 c = a - b;
        return c;
    }
    /**
     * @dev Returns the subtraction of two signed integers, reverting on overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the largest of two numbers of 256 bits.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }
    /**
     * @dev Returns the smallest of two numbers of 256 bits.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a * b;
        _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
        return c;
    }
    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        return a / b;
    }
    function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        if (a == 0) {
            return 0;
        } else {
            return 1 + (a - 1) / b;
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
// Based on the EnumerableMap library from OpenZeppelin contracts, altered to include the following:
//  * a map from IERC20 to bytes32
//  * entries are stored in mappings instead of arrays, reducing implicit storage reads for out-of-bounds checks
//  * unchecked_at and unchecked_valueAt, which allow for more gas efficient data reads in some scenarios
//  * unchecked_indexOf and unchecked_setAt, which allow for more gas efficient data writes in some scenarios
//
// Additionally, the base private functions that work on bytes32 were removed and replaced with a native implementation
// for IERC20 keys, to reduce bytecode size and runtime costs.
// We're using non-standard casing for the unchecked functions to differentiate them, so we need to turn off that rule
// solhint-disable func-name-mixedcase
import "./IERC20.sol";
import "../helpers/BalancerErrors.sol";
/**
 * @dev Library for managing an enumerable variant of Solidity's
 * https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
 * type.
 *
 * Maps have the following properties:
 *
 * - Entries are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Entries are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableMap for EnumerableMap.UintToAddressMap;
 *
 *     // Declare a set state variable
 *     EnumerableMap.UintToAddressMap private myMap;
 * }
 * ```
 */
library EnumerableMap {
    // The original OpenZeppelin implementation uses a generic Map type with bytes32 keys: this was replaced with
    // IERC20ToBytes32Map, which uses IERC20 keys natively, resulting in more dense bytecode.
    struct IERC20ToBytes32MapEntry {
        IERC20 _key;
        bytes32 _value;
    }
    struct IERC20ToBytes32Map {
        // Number of entries in the map
        uint256 _length;
        // Storage of map keys and values
        mapping(uint256 => IERC20ToBytes32MapEntry) _entries;
        // Position of the entry defined by a key in the `entries` array, plus 1
        // because index 0 means a key is not in the map.
        mapping(IERC20 => uint256) _indexes;
    }
    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(
        IERC20ToBytes32Map storage map,
        IERC20 key,
        bytes32 value
    ) internal returns (bool) {
        // We read and store the key's index to prevent multiple reads from the same storage slot
        uint256 keyIndex = map._indexes[key];
        // Equivalent to !contains(map, key)
        if (keyIndex == 0) {
            uint256 previousLength = map._length;
            map._entries[previousLength] = IERC20ToBytes32MapEntry({ _key: key, _value: value });
            map._length = previousLength + 1;
            // The entry is stored at previousLength, but we add 1 to all indexes
            // and use 0 as a sentinel value
            map._indexes[key] = previousLength + 1;
            return true;
        } else {
            map._entries[keyIndex - 1]._value = value;
            return false;
        }
    }
    /**
     * @dev Updates the value for an entry, given its key's index. The key index can be retrieved via
     * {unchecked_indexOf}, and it should be noted that key indices may change when calling {set} or {remove}. O(1).
     *
     * This function performs one less storage read than {set}, but it should only be used when `index` is known to be
     * within bounds.
     */
    function unchecked_setAt(
        IERC20ToBytes32Map storage map,
        uint256 index,
        bytes32 value
    ) internal {
        map._entries[index]._value = value;
    }
    /**
     * @dev Removes a key-value pair from a map. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(IERC20ToBytes32Map storage map, IERC20 key) internal returns (bool) {
        // We read and store the key's index to prevent multiple reads from the same storage slot
        uint256 keyIndex = map._indexes[key];
        // Equivalent to contains(map, key)
        if (keyIndex != 0) {
            // To delete a key-value pair from the _entries pseudo-array in O(1), we swap the entry to delete with the
            // one at the highest index, and then remove this last entry (sometimes called as 'swap and pop').
            // This modifies the order of the pseudo-array, as noted in {at}.
            uint256 toDeleteIndex = keyIndex - 1;
            uint256 lastIndex = map._length - 1;
            // When the entry to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
            IERC20ToBytes32MapEntry storage lastEntry = map._entries[lastIndex];
            // Move the last entry to the index where the entry to delete is
            map._entries[toDeleteIndex] = lastEntry;
            // Update the index for the moved entry
            map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based
            // Delete the slot where the moved entry was stored
            delete map._entries[lastIndex];
            map._length = lastIndex;
            // Delete the index for the deleted slot
            delete map._indexes[key];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(IERC20ToBytes32Map storage map, IERC20 key) internal view returns (bool) {
        return map._indexes[key] != 0;
    }
    /**
     * @dev Returns the number of key-value pairs in the map. O(1).
     */
    function length(IERC20ToBytes32Map storage map) internal view returns (uint256) {
        return map._length;
    }
    /**
     * @dev Returns the key-value pair stored at position `index` in the map. O(1).
     *
     * Note that there are no guarantees on the ordering of entries inside the
     * array, and it may change when more entries are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(IERC20ToBytes32Map storage map, uint256 index) internal view returns (IERC20, bytes32) {
        _require(map._length > index, Errors.OUT_OF_BOUNDS);
        return unchecked_at(map, index);
    }
    /**
     * @dev Same as {at}, except this doesn't revert if `index` it outside of the map (i.e. if it is equal or larger
     * than {length}). O(1).
     *
     * This function performs one less storage read than {at}, but should only be used when `index` is known to be
     * within bounds.
     */
    function unchecked_at(IERC20ToBytes32Map storage map, uint256 index) internal view returns (IERC20, bytes32) {
        IERC20ToBytes32MapEntry storage entry = map._entries[index];
        return (entry._key, entry._value);
    }
    /**
     * @dev Same as {unchecked_At}, except it only returns the value and not the key (performing one less storage
     * read). O(1).
     */
    function unchecked_valueAt(IERC20ToBytes32Map storage map, uint256 index) internal view returns (bytes32) {
        return map._entries[index]._value;
    }
    /**
     * @dev Returns the value associated with `key`. O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map. Reverts with `errorCode` otherwise.
     */
    function get(
        IERC20ToBytes32Map storage map,
        IERC20 key,
        uint256 errorCode
    ) internal view returns (bytes32) {
        uint256 index = map._indexes[key];
        _require(index > 0, errorCode);
        return unchecked_valueAt(map, index - 1);
    }
    /**
     * @dev Returns the index for `key` **plus one**. Does not revert if the key is not in the map, and returns 0
     * instead.
     */
    function unchecked_indexOf(IERC20ToBytes32Map storage map, IERC20 key) internal view returns (uint256) {
        return map._indexes[key];
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
// Based on the EnumerableSet library from OpenZeppelin contracts, altered to remove the base private functions that
// work on bytes32, replacing them with a native implementation for address values, to reduce bytecode size and runtime
// costs.
// The `unchecked_at` function was also added, which allows for more gas efficient data reads in some scenarios.
/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // The original OpenZeppelin implementation uses a generic Set type with bytes32 values: this was replaced with
    // AddressSet, which uses address keys natively, resulting in more dense bytecode.
    struct AddressSet {
        // Storage of set values
        address[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(address => uint256) _indexes;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        if (!contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];
        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.
            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;
            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
            address lastValue = set._values[lastIndex];
            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastValue;
            // Update the index for the moved value
            set._indexes[lastValue] = toDeleteIndex + 1; // All indexes are 1-based
            // Delete the slot where the moved value was stored
            set._values.pop();
            // Delete the index for the deleted slot
            delete set._indexes[value];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return set._indexes[value] != 0;
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return set._values.length;
    }
    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        _require(set._values.length > index, Errors.OUT_OF_BOUNDS);
        return unchecked_at(set, index);
    }
    /**
     * @dev Same as {at}, except this doesn't revert if `index` it outside of the set (i.e. if it is equal or larger
     * than {length}). O(1).
     *
     * This function performs one less storage read than {at}, but should only be used when `index` is known to be
     * within bounds.
     */
    function unchecked_at(AddressSet storage set, uint256 index) internal view returns (address) {
        return set._values[index];
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {
    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        _require(value < 2**255, Errors.SAFE_CAST_VALUE_CANT_FIT_INT256);
        return int256(value);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/math/Math.sol";
import "../lib/helpers/BalancerErrors.sol";
import "../lib/helpers/InputHelpers.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "./Fees.sol";
import "./PoolTokens.sol";
import "./UserBalance.sol";
import "./interfaces/IBasePool.sol";
/**
 * @dev Stores the Asset Managers (by Pool and token), and implements the top level Asset Manager and Pool interfaces,
 * such as registering and deregistering tokens, joining and exiting Pools, and informational functions like `getPool`
 * and `getPoolTokens`, delegating to specialization-specific functions as needed.
 *
 * `managePoolBalance` handles all Asset Manager interactions.
 */
abstract contract PoolBalances is Fees, ReentrancyGuard, PoolTokens, UserBalance {
    using Math for uint256;
    using SafeERC20 for IERC20;
    using BalanceAllocation for bytes32;
    using BalanceAllocation for bytes32[];
    function joinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        JoinPoolRequest memory request
    ) external payable override whenNotPaused {
        // This function doesn't have the nonReentrant modifier: it is applied to `_joinOrExit` instead.
        // Note that `recipient` is not actually payable in the context of a join - we cast it because we handle both
        // joins and exits at once.
        _joinOrExit(PoolBalanceChangeKind.JOIN, poolId, sender, payable(recipient), _toPoolBalanceChange(request));
    }
    function exitPool(
        bytes32 poolId,
        address sender,
        address payable recipient,
        ExitPoolRequest memory request
    ) external override {
        // This function doesn't have the nonReentrant modifier: it is applied to `_joinOrExit` instead.
        _joinOrExit(PoolBalanceChangeKind.EXIT, poolId, sender, recipient, _toPoolBalanceChange(request));
    }
    // This has the exact same layout as JoinPoolRequest and ExitPoolRequest, except the `maxAmountsIn` and
    // `minAmountsOut` are called `limits`. Internally we use this struct for both since these two functions are quite
    // similar, but expose the others to callers for clarity.
    struct PoolBalanceChange {
        IAsset[] assets;
        uint256[] limits;
        bytes userData;
        bool useInternalBalance;
    }
    /**
     * @dev Converts a JoinPoolRequest into a PoolBalanceChange, with no runtime cost.
     */
    function _toPoolBalanceChange(JoinPoolRequest memory request)
        private
        pure
        returns (PoolBalanceChange memory change)
    {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            change := request
        }
    }
    /**
     * @dev Converts an ExitPoolRequest into a PoolBalanceChange, with no runtime cost.
     */
    function _toPoolBalanceChange(ExitPoolRequest memory request)
        private
        pure
        returns (PoolBalanceChange memory change)
    {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            change := request
        }
    }
    /**
     * @dev Implements both `joinPool` and `exitPool`, based on `kind`.
     */
    function _joinOrExit(
        PoolBalanceChangeKind kind,
        bytes32 poolId,
        address sender,
        address payable recipient,
        PoolBalanceChange memory change
    ) private nonReentrant withRegisteredPool(poolId) authenticateFor(sender) {
        // This function uses a large number of stack variables (poolId, sender and recipient, balances, amounts, fees,
        // etc.), which leads to 'stack too deep' issues. It relies on private functions with seemingly arbitrary
        // interfaces to work around this limitation.
        InputHelpers.ensureInputLengthMatch(change.assets.length, change.limits.length);
        // We first check that the caller passed the Pool's registered tokens in the correct order, and retrieve the
        // current balance for each.
        IERC20[] memory tokens = _translateToIERC20(change.assets);
        bytes32[] memory balances = _validateTokensAndGetBalances(poolId, tokens);
        // The bulk of the work is done here: the corresponding Pool hook is called, its final balances are computed,
        // assets are transferred, and fees are paid.
        (
            bytes32[] memory finalBalances,
            uint256[] memory amountsInOrOut,
            uint256[] memory paidProtocolSwapFeeAmounts
        ) = _callPoolBalanceChange(kind, poolId, sender, recipient, change, balances);
        // All that remains is storing the new Pool balances.
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            _setTwoTokenPoolCashBalances(poolId, tokens[0], finalBalances[0], tokens[1], finalBalances[1]);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            _setMinimalSwapInfoPoolBalances(poolId, tokens, finalBalances);
        } else {
            // PoolSpecialization.GENERAL
            _setGeneralPoolBalances(poolId, finalBalances);
        }
        bool positive = kind == PoolBalanceChangeKind.JOIN; // Amounts in are positive, out are negative
        emit PoolBalanceChanged(
            poolId,
            sender,
            tokens,
            // We can unsafely cast to int256 because balances are actually stored as uint112
            _unsafeCastToInt256(amountsInOrOut, positive),
            paidProtocolSwapFeeAmounts
        );
    }
    /**
     * @dev Calls the corresponding Pool hook to get the amounts in/out plus protocol fee amounts, and performs the
     * associated token transfers and fee payments, returning the Pool's final balances.
     */
    function _callPoolBalanceChange(
        PoolBalanceChangeKind kind,
        bytes32 poolId,
        address sender,
        address payable recipient,
        PoolBalanceChange memory change,
        bytes32[] memory balances
    )
        private
        returns (
            bytes32[] memory finalBalances,
            uint256[] memory amountsInOrOut,
            uint256[] memory dueProtocolFeeAmounts
        )
    {
        (uint256[] memory totalBalances, uint256 lastChangeBlock) = balances.totalsAndLastChangeBlock();
        IBasePool pool = IBasePool(_getPoolAddress(poolId));
        (amountsInOrOut, dueProtocolFeeAmounts) = kind == PoolBalanceChangeKind.JOIN
            ? pool.onJoinPool(
                poolId,
                sender,
                recipient,
                totalBalances,
                lastChangeBlock,
                _getProtocolSwapFeePercentage(),
                change.userData
            )
            : pool.onExitPool(
                poolId,
                sender,
                recipient,
                totalBalances,
                lastChangeBlock,
                _getProtocolSwapFeePercentage(),
                change.userData
            );
        InputHelpers.ensureInputLengthMatch(balances.length, amountsInOrOut.length, dueProtocolFeeAmounts.length);
        // The Vault ignores the `recipient` in joins and the `sender` in exits: it is up to the Pool to keep track of
        // their participation.
        finalBalances = kind == PoolBalanceChangeKind.JOIN
            ? _processJoinPoolTransfers(sender, change, balances, amountsInOrOut, dueProtocolFeeAmounts)
            : _processExitPoolTransfers(recipient, change, balances, amountsInOrOut, dueProtocolFeeAmounts);
    }
    /**
     * @dev Transfers `amountsIn` from `sender`, checking that they are within their accepted limits, and pays
     * accumulated protocol swap fees.
     *
     * Returns the Pool's final balances, which are the current balances plus `amountsIn` minus accumulated protocol
     * swap fees.
     */
    function _processJoinPoolTransfers(
        address sender,
        PoolBalanceChange memory change,
        bytes32[] memory balances,
        uint256[] memory amountsIn,
        uint256[] memory dueProtocolFeeAmounts
    ) private returns (bytes32[] memory finalBalances) {
        // We need to track how much of the received ETH was used and wrapped into WETH to return any excess.
        uint256 wrappedEth = 0;
        finalBalances = new bytes32[](balances.length);
        for (uint256 i = 0; i < change.assets.length; ++i) {
            uint256 amountIn = amountsIn[i];
            _require(amountIn <= change.limits[i], Errors.JOIN_ABOVE_MAX);
            // Receive assets from the sender - possibly from Internal Balance.
            IAsset asset = change.assets[i];
            _receiveAsset(asset, amountIn, sender, change.useInternalBalance);
            if (_isETH(asset)) {
                wrappedEth = wrappedEth.add(amountIn);
            }
            uint256 feeAmount = dueProtocolFeeAmounts[i];
            _payFeeAmount(_translateToIERC20(asset), feeAmount);
            // Compute the new Pool balances. Note that the fee amount might be larger than `amountIn`,
            // resulting in an overall decrease of the Pool's balance for a token.
            finalBalances[i] = (amountIn >= feeAmount) // This lets us skip checked arithmetic
                ? balances[i].increaseCash(amountIn - feeAmount)
                : balances[i].decreaseCash(feeAmount - amountIn);
        }
        // Handle any used and remaining ETH.
        _handleRemainingEth(wrappedEth);
    }
    /**
     * @dev Transfers `amountsOut` to `recipient`, checking that they are within their accepted limits, and pays
     * accumulated protocol swap fees from the Pool.
     *
     * Returns the Pool's final balances, which are the current `balances` minus `amountsOut` and fees paid
     * (`dueProtocolFeeAmounts`).
     */
    function _processExitPoolTransfers(
        address payable recipient,
        PoolBalanceChange memory change,
        bytes32[] memory balances,
        uint256[] memory amountsOut,
        uint256[] memory dueProtocolFeeAmounts
    ) private returns (bytes32[] memory finalBalances) {
        finalBalances = new bytes32[](balances.length);
        for (uint256 i = 0; i < change.assets.length; ++i) {
            uint256 amountOut = amountsOut[i];
            _require(amountOut >= change.limits[i], Errors.EXIT_BELOW_MIN);
            // Send tokens to the recipient - possibly to Internal Balance
            IAsset asset = change.assets[i];
            _sendAsset(asset, amountOut, recipient, change.useInternalBalance);
            uint256 feeAmount = dueProtocolFeeAmounts[i];
            _payFeeAmount(_translateToIERC20(asset), feeAmount);
            // Compute the new Pool balances. A Pool's token balance always decreases after an exit (potentially by 0).
            finalBalances[i] = balances[i].decreaseCash(amountOut.add(feeAmount));
        }
    }
    /**
     * @dev Returns the total balance for `poolId`'s `expectedTokens`.
     *
     * `expectedTokens` must exactly equal the token array returned by `getPoolTokens`: both arrays must have the same
     * length, elements and order. Additionally, the Pool must have at least one registered token.
     */
    function _validateTokensAndGetBalances(bytes32 poolId, IERC20[] memory expectedTokens)
        private
        view
        returns (bytes32[] memory)
    {
        (IERC20[] memory actualTokens, bytes32[] memory balances) = _getPoolTokens(poolId);
        InputHelpers.ensureInputLengthMatch(actualTokens.length, expectedTokens.length);
        _require(actualTokens.length > 0, Errors.POOL_NO_TOKENS);
        for (uint256 i = 0; i < actualTokens.length; ++i) {
            _require(actualTokens[i] == expectedTokens[i], Errors.TOKENS_MISMATCH);
        }
        return balances;
    }
    /**
     * @dev Casts an array of uint256 to int256, setting the sign of the result according to the `positive` flag,
     * without checking whether the values fit in the signed 256 bit range.
     */
    function _unsafeCastToInt256(uint256[] memory values, bool positive)
        private
        pure
        returns (int256[] memory signedValues)
    {
        signedValues = new int256[](values.length);
        for (uint256 i = 0; i < values.length; i++) {
            signedValues[i] = positive ? int256(values[i]) : -int256(values[i]);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../../lib/openzeppelin/IERC20.sol";
import "./IVault.sol";
interface IPoolSwapStructs {
    // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
    // IMinimalSwapInfoPool.
    //
    // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
    // 'given out') which indicates whether or not the amount sent by the pool is known.
    //
    // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
    // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
    //
    // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
    // some Pools.
    //
    // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
    // one Pool.
    //
    // The meaning of `lastChangeBlock` depends on the Pool specialization:
    //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
    //    balance.
    //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
    //
    // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
    // where the Pool sends the outgoing tokens.
    //
    // `userData` is extra data provided by the caller - typically a signature from a trusted party.
    struct SwapRequest {
        IVault.SwapKind kind;
        IERC20 tokenIn;
        IERC20 tokenOut;
        uint256 amount;
        // Misc data
        bytes32 poolId;
        uint256 lastChangeBlock;
        address from;
        address to;
        bytes userData;
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "./IBasePool.sol";
/**
 * @dev IPools with the General specialization setting should implement this interface.
 *
 * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
 * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will
 * grant to the pool in a 'given out' swap.
 *
 * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
 * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
 * indeed the Vault.
 */
interface IGeneralPool is IBasePool {
    function onSwap(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut
    ) external returns (uint256 amount);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "./IBasePool.sol";
/**
 * @dev Pool contracts with the MinimalSwapInfo or TwoToken specialization settings should implement this interface.
 *
 * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
 * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will grant
 * to the pool in a 'given out' swap.
 *
 * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
 * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
 * indeed the Vault.
 */
interface IMinimalSwapInfoPool is IBasePool {
    function onSwap(
        SwapRequest memory swapRequest,
        uint256 currentBalanceTokenIn,
        uint256 currentBalanceTokenOut
    ) external returns (uint256 amount);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../../lib/math/Math.sol";
// This library is used to create a data structure that represents a token's balance for a Pool. 'cash' is how many
// tokens the Pool has sitting inside of the Vault. 'managed' is how many tokens were withdrawn from the Vault by the
// Pool's Asset Manager. 'total' is the sum of these two, and represents the Pool's total token balance, including
// tokens that are *not* inside of the Vault.
//
// 'cash' is updated whenever tokens enter and exit the Vault, while 'managed' is only updated if the reason tokens are
// moving is due to an Asset Manager action. This is reflected in the different methods available: 'increaseCash'
// and 'decreaseCash' for swaps and add/remove liquidity events, and 'cashToManaged' and 'managedToCash' for events
// transferring funds to and from the Asset Manager.
//
// The Vault disallows the Pool's 'cash' from becoming negative. In other words, it can never use any tokens that are
// not inside the Vault.
//
// One of the goals of this library is to store the entire token balance in a single storage slot, which is why we use
// 112 bit unsigned integers for 'cash' and 'managed'. For consistency, we also disallow any combination of 'cash' and
// 'managed' that yields a 'total' that doesn't fit in 112 bits.
//
// The remaining 32 bits of the slot are used to store the most recent block when the total balance changed. This
// can be used to implement price oracles that are resilient to 'sandwich' attacks.
//
// We could use a Solidity struct to pack these three values together in a single storage slot, but unfortunately
// Solidity only allows for structs to live in either storage, calldata or memory. Because a memory struct still takes
// up a slot in the stack (to store its memory location), and because the entire balance fits in a single stack slot
// (two 112 bit values plus the 32 bit block), using memory is strictly less gas performant. Therefore, we do manual
// packing and unpacking.
//
// Since we cannot define new types, we rely on bytes32 to represent these values instead, as it doesn't have any
// associated arithmetic operations and therefore reduces the chance of misuse.
library BalanceAllocation {
    using Math for uint256;
    // The 'cash' portion of the balance is stored in the least significant 112 bits of a 256 bit word, while the
    // 'managed' part uses the following 112 bits. The most significant 32 bits are used to store the block
    /**
     * @dev Returns the total amount of Pool tokens, including those that are not currently in the Vault ('managed').
     */
    function total(bytes32 balance) internal pure returns (uint256) {
        // Since 'cash' and 'managed' are 112 bit values, we don't need checked arithmetic. Additionally, `toBalance`
        // ensures that 'total' always fits in 112 bits.
        return cash(balance) + managed(balance);
    }
    /**
     * @dev Returns the amount of Pool tokens currently in the Vault.
     */
    function cash(bytes32 balance) internal pure returns (uint256) {
        uint256 mask = 2**(112) - 1;
        return uint256(balance) & mask;
    }
    /**
     * @dev Returns the amount of Pool tokens that are being managed by an Asset Manager.
     */
    function managed(bytes32 balance) internal pure returns (uint256) {
        uint256 mask = 2**(112) - 1;
        return uint256(balance >> 112) & mask;
    }
    /**
     * @dev Returns the last block when the total balance changed.
     */
    function lastChangeBlock(bytes32 balance) internal pure returns (uint256) {
        uint256 mask = 2**(32) - 1;
        return uint256(balance >> 224) & mask;
    }
    /**
     * @dev Returns the difference in 'managed' between two balances.
     */
    function managedDelta(bytes32 newBalance, bytes32 oldBalance) internal pure returns (int256) {
        // Because `managed` is a 112 bit value, we can safely perform unchecked arithmetic in 256 bits.
        return int256(managed(newBalance)) - int256(managed(oldBalance));
    }
    /**
     * @dev Returns the total balance for each entry in `balances`, as well as the latest block when the total
     * balance of *any* of them last changed.
     */
    function totalsAndLastChangeBlock(bytes32[] memory balances)
        internal
        pure
        returns (
            uint256[] memory results,
            uint256 lastChangeBlock_ // Avoid shadowing
        )
    {
        results = new uint256[](balances.length);
        lastChangeBlock_ = 0;
        for (uint256 i = 0; i < results.length; i++) {
            bytes32 balance = balances[i];
            results[i] = total(balance);
            lastChangeBlock_ = Math.max(lastChangeBlock_, lastChangeBlock(balance));
        }
    }
    /**
     * @dev Returns true if `balance`'s 'total' balance is zero. Costs less gas than computing 'total' and comparing
     * with zero.
     */
    function isZero(bytes32 balance) internal pure returns (bool) {
        // We simply need to check the least significant 224 bytes of the word: the block does not affect this.
        uint256 mask = 2**(224) - 1;
        return (uint256(balance) & mask) == 0;
    }
    /**
     * @dev Returns true if `balance`'s 'total' balance is not zero. Costs less gas than computing 'total' and comparing
     * with zero.
     */
    function isNotZero(bytes32 balance) internal pure returns (bool) {
        return !isZero(balance);
    }
    /**
     * @dev Packs together `cash` and `managed` amounts with a block to create a balance value.
     *
     * For consistency, this also checks that the sum of `cash` and `managed` (`total`) fits in 112 bits.
     */
    function toBalance(
        uint256 _cash,
        uint256 _managed,
        uint256 _blockNumber
    ) internal pure returns (bytes32) {
        uint256 _total = _cash + _managed;
        // Since both 'cash' and 'managed' are positive integers, by checking that their sum ('total') fits in 112 bits
        // we are also indirectly checking that both 'cash' and 'managed' themselves fit in 112 bits.
        _require(_total >= _cash && _total < 2**112, Errors.BALANCE_TOTAL_OVERFLOW);
        // We assume the block fits in 32 bits - this is expected to hold for at least a few decades.
        return _pack(_cash, _managed, _blockNumber);
    }
    /**
     * @dev Increases a Pool's 'cash' (and therefore its 'total'). Called when Pool tokens are sent to the Vault (except
     * for Asset Manager deposits).
     *
     * Updates the last total balance change block, even if `amount` is zero.
     */
    function increaseCash(bytes32 balance, uint256 amount) internal view returns (bytes32) {
        uint256 newCash = cash(balance).add(amount);
        uint256 currentManaged = managed(balance);
        uint256 newLastChangeBlock = block.number;
        return toBalance(newCash, currentManaged, newLastChangeBlock);
    }
    /**
     * @dev Decreases a Pool's 'cash' (and therefore its 'total'). Called when Pool tokens are sent from the Vault
     * (except for Asset Manager withdrawals).
     *
     * Updates the last total balance change block, even if `amount` is zero.
     */
    function decreaseCash(bytes32 balance, uint256 amount) internal view returns (bytes32) {
        uint256 newCash = cash(balance).sub(amount);
        uint256 currentManaged = managed(balance);
        uint256 newLastChangeBlock = block.number;
        return toBalance(newCash, currentManaged, newLastChangeBlock);
    }
    /**
     * @dev Moves 'cash' into 'managed', leaving 'total' unchanged. Called when an Asset Manager withdraws Pool tokens
     * from the Vault.
     */
    function cashToManaged(bytes32 balance, uint256 amount) internal pure returns (bytes32) {
        uint256 newCash = cash(balance).sub(amount);
        uint256 newManaged = managed(balance).add(amount);
        uint256 currentLastChangeBlock = lastChangeBlock(balance);
        return toBalance(newCash, newManaged, currentLastChangeBlock);
    }
    /**
     * @dev Moves 'managed' into 'cash', leaving 'total' unchanged. Called when an Asset Manager deposits Pool tokens
     * into the Vault.
     */
    function managedToCash(bytes32 balance, uint256 amount) internal pure returns (bytes32) {
        uint256 newCash = cash(balance).add(amount);
        uint256 newManaged = managed(balance).sub(amount);
        uint256 currentLastChangeBlock = lastChangeBlock(balance);
        return toBalance(newCash, newManaged, currentLastChangeBlock);
    }
    /**
     * @dev Sets 'managed' balance to an arbitrary value, changing 'total'. Called when the Asset Manager reports
     * profits or losses. It's the Manager's responsibility to provide a meaningful value.
     *
     * Updates the last total balance change block, even if `newManaged` is equal to the current 'managed' value.
     */
    function setManaged(bytes32 balance, uint256 newManaged) internal view returns (bytes32) {
        uint256 currentCash = cash(balance);
        uint256 newLastChangeBlock = block.number;
        return toBalance(currentCash, newManaged, newLastChangeBlock);
    }
    // Alternative mode for Pools with the Two Token specialization setting
    // Instead of storing cash and external for each 'token in' a single storage slot, Two Token Pools store the cash
    // for both tokens in the same slot, and the managed for both in another one. This reduces the gas cost for swaps,
    // because the only slot that needs to be updated is the one with the cash. However, it also means that managing
    // balances is more cumbersome, as both tokens need to be read/written at the same time.
    //
    // The field with both cash balances packed is called sharedCash, and the one with external amounts is called
    // sharedManaged. These two are collectively called the 'shared' balance fields. In both of these, the portion
    // that corresponds to token A is stored in the least significant 112 bits of a 256 bit word, while token B's part
    // uses the next least significant 112 bits.
    //
    // Because only cash is written to during a swap, we store the last total balance change block with the
    // packed cash fields. Typically Pools have a distinct block per token: in the case of Two Token Pools they
    // are the same.
    /**
     * @dev Extracts the part of the balance that corresponds to token A. This function can be used to decode both
     * shared cash and managed balances.
     */
    function _decodeBalanceA(bytes32 sharedBalance) private pure returns (uint256) {
        uint256 mask = 2**(112) - 1;
        return uint256(sharedBalance) & mask;
    }
    /**
     * @dev Extracts the part of the balance that corresponds to token B. This function can be used to decode both
     * shared cash and managed balances.
     */
    function _decodeBalanceB(bytes32 sharedBalance) private pure returns (uint256) {
        uint256 mask = 2**(112) - 1;
        return uint256(sharedBalance >> 112) & mask;
    }
    // To decode the last balance change block, we can simply use the `blockNumber` function.
    /**
     * @dev Unpacks the shared token A and token B cash and managed balances into the balance for token A.
     */
    function fromSharedToBalanceA(bytes32 sharedCash, bytes32 sharedManaged) internal pure returns (bytes32) {
        // Note that we extract the block from the sharedCash field, which is the one that is updated by swaps.
        // Both token A and token B use the same block
        return toBalance(_decodeBalanceA(sharedCash), _decodeBalanceA(sharedManaged), lastChangeBlock(sharedCash));
    }
    /**
     * @dev Unpacks the shared token A and token B cash and managed balances into the balance for token B.
     */
    function fromSharedToBalanceB(bytes32 sharedCash, bytes32 sharedManaged) internal pure returns (bytes32) {
        // Note that we extract the block from the sharedCash field, which is the one that is updated by swaps.
        // Both token A and token B use the same block
        return toBalance(_decodeBalanceB(sharedCash), _decodeBalanceB(sharedManaged), lastChangeBlock(sharedCash));
    }
    /**
     * @dev Returns the sharedCash shared field, given the current balances for token A and token B.
     */
    function toSharedCash(bytes32 tokenABalance, bytes32 tokenBBalance) internal pure returns (bytes32) {
        // Both balances are assigned the same block  Since it is possible a single one of them has changed (for
        // example, in an Asset Manager update), we keep the latest (largest) one.
        uint32 newLastChangeBlock = uint32(Math.max(lastChangeBlock(tokenABalance), lastChangeBlock(tokenBBalance)));
        return _pack(cash(tokenABalance), cash(tokenBBalance), newLastChangeBlock);
    }
    /**
     * @dev Returns the sharedManaged shared field, given the current balances for token A and token B.
     */
    function toSharedManaged(bytes32 tokenABalance, bytes32 tokenBBalance) internal pure returns (bytes32) {
        // We don't bother storing a last change block, as it is read from the shared cash field.
        return _pack(managed(tokenABalance), managed(tokenBBalance), 0);
    }
    // Shared functions
    /**
     * @dev Packs together two uint112 and one uint32 into a bytes32
     */
    function _pack(
        uint256 _leastSignificant,
        uint256 _midSignificant,
        uint256 _mostSignificant
    ) private pure returns (bytes32) {
        return bytes32((_mostSignificant << 224) + (_midSignificant << 112) + _leastSignificant);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/helpers/BalancerErrors.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "./AssetManagers.sol";
import "./PoolRegistry.sol";
import "./balances/BalanceAllocation.sol";
abstract contract PoolTokens is ReentrancyGuard, PoolRegistry, AssetManagers {
    using BalanceAllocation for bytes32;
    using BalanceAllocation for bytes32[];
    function registerTokens(
        bytes32 poolId,
        IERC20[] memory tokens,
        address[] memory assetManagers
    ) external override nonReentrant whenNotPaused onlyPool(poolId) {
        InputHelpers.ensureInputLengthMatch(tokens.length, assetManagers.length);
        // Validates token addresses and assigns Asset Managers
        for (uint256 i = 0; i < tokens.length; ++i) {
            IERC20 token = tokens[i];
            _require(token != IERC20(0), Errors.INVALID_TOKEN);
            _poolAssetManagers[poolId][token] = assetManagers[i];
        }
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            _require(tokens.length == 2, Errors.TOKENS_LENGTH_MUST_BE_2);
            _registerTwoTokenPoolTokens(poolId, tokens[0], tokens[1]);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            _registerMinimalSwapInfoPoolTokens(poolId, tokens);
        } else {
            // PoolSpecialization.GENERAL
            _registerGeneralPoolTokens(poolId, tokens);
        }
        emit TokensRegistered(poolId, tokens, assetManagers);
    }
    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens)
        external
        override
        nonReentrant
        whenNotPaused
        onlyPool(poolId)
    {
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            _require(tokens.length == 2, Errors.TOKENS_LENGTH_MUST_BE_2);
            _deregisterTwoTokenPoolTokens(poolId, tokens[0], tokens[1]);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            _deregisterMinimalSwapInfoPoolTokens(poolId, tokens);
        } else {
            // PoolSpecialization.GENERAL
            _deregisterGeneralPoolTokens(poolId, tokens);
        }
        // The deregister calls above ensure the total token balance is zero. Therefore it is now safe to remove any
        // associated Asset Managers, since they hold no Pool balance.
        for (uint256 i = 0; i < tokens.length; ++i) {
            delete _poolAssetManagers[poolId][tokens[i]];
        }
        emit TokensDeregistered(poolId, tokens);
    }
    function getPoolTokens(bytes32 poolId)
        external
        view
        override
        withRegisteredPool(poolId)
        returns (
            IERC20[] memory tokens,
            uint256[] memory balances,
            uint256 lastChangeBlock
        )
    {
        bytes32[] memory rawBalances;
        (tokens, rawBalances) = _getPoolTokens(poolId);
        (balances, lastChangeBlock) = rawBalances.totalsAndLastChangeBlock();
    }
    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
        external
        view
        override
        withRegisteredPool(poolId)
        returns (
            uint256 cash,
            uint256 managed,
            uint256 lastChangeBlock,
            address assetManager
        )
    {
        bytes32 balance;
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            balance = _getTwoTokenPoolBalance(poolId, token);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            balance = _getMinimalSwapInfoPoolBalance(poolId, token);
        } else {
            // PoolSpecialization.GENERAL
            balance = _getGeneralPoolBalance(poolId, token);
        }
        cash = balance.cash();
        managed = balance.managed();
        lastChangeBlock = balance.lastChangeBlock();
        assetManager = _poolAssetManagers[poolId][token];
    }
    /**
     * @dev Returns all of `poolId`'s registered tokens, along with their raw balances.
     */
    function _getPoolTokens(bytes32 poolId) internal view returns (IERC20[] memory tokens, bytes32[] memory balances) {
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            return _getTwoTokenPoolTokens(poolId);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            return _getMinimalSwapInfoPoolTokens(poolId);
        } else {
            // PoolSpecialization.GENERAL
            return _getGeneralPoolTokens(poolId);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/helpers/BalancerErrors.sol";
import "../lib/math/Math.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "../lib/openzeppelin/SafeCast.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "./AssetTransfersHandler.sol";
import "./VaultAuthorization.sol";
/**
 * Implement User Balance interactions, which combine Internal Balance and using the Vault's ERC20 allowance.
 *
 * Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
 * transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
 * when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
 * gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
 *
 * Internal Balance management features batching, which means a single contract call can be used to perform multiple
 * operations of different kinds, with different senders and recipients, at once.
 */
abstract contract UserBalance is ReentrancyGuard, AssetTransfersHandler, VaultAuthorization {
    using Math for uint256;
    using SafeCast for uint256;
    using SafeERC20 for IERC20;
    // Internal Balance for each token, for each account.
    mapping(address => mapping(IERC20 => uint256)) private _internalTokenBalance;
    function getInternalBalance(address user, IERC20[] memory tokens)
        external
        view
        override
        returns (uint256[] memory balances)
    {
        balances = new uint256[](tokens.length);
        for (uint256 i = 0; i < tokens.length; i++) {
            balances[i] = _getInternalBalance(user, tokens[i]);
        }
    }
    function manageUserBalance(UserBalanceOp[] memory ops) external payable override nonReentrant {
        // We need to track how much of the received ETH was used and wrapped into WETH to return any excess.
        uint256 ethWrapped = 0;
        // Cache for these checks so we only perform them once (if at all).
        bool checkedCallerIsRelayer = false;
        bool checkedNotPaused = false;
        for (uint256 i = 0; i < ops.length; i++) {
            UserBalanceOpKind kind;
            IAsset asset;
            uint256 amount;
            address sender;
            address payable recipient;
            // This destructuring by calling `_validateUserBalanceOp` seems odd, but results in reduced bytecode size.
            (kind, asset, amount, sender, recipient, checkedCallerIsRelayer) = _validateUserBalanceOp(
                ops[i],
                checkedCallerIsRelayer
            );
            if (kind == UserBalanceOpKind.WITHDRAW_INTERNAL) {
                // Internal Balance withdrawals can always be performed by an authorized account.
                _withdrawFromInternalBalance(asset, sender, recipient, amount);
            } else {
                // All other operations are blocked if the contract is paused.
                // We cache the result of the pause check and skip it for other operations in this same transaction
                // (if any).
                if (!checkedNotPaused) {
                    _ensureNotPaused();
                    checkedNotPaused = true;
                }
                if (kind == UserBalanceOpKind.DEPOSIT_INTERNAL) {
                    _depositToInternalBalance(asset, sender, recipient, amount);
                    // Keep track of all ETH wrapped into WETH as part of a deposit.
                    if (_isETH(asset)) {
                        ethWrapped = ethWrapped.add(amount);
                    }
                } else {
                    // Transfers don't support ETH.
                    _require(!_isETH(asset), Errors.CANNOT_USE_ETH_SENTINEL);
                    IERC20 token = _asIERC20(asset);
                    if (kind == UserBalanceOpKind.TRANSFER_INTERNAL) {
                        _transferInternalBalance(token, sender, recipient, amount);
                    } else {
                        // TRANSFER_EXTERNAL
                        _transferToExternalBalance(token, sender, recipient, amount);
                    }
                }
            }
        }
        // Handle any remaining ETH.
        _handleRemainingEth(ethWrapped);
    }
    function _depositToInternalBalance(
        IAsset asset,
        address sender,
        address recipient,
        uint256 amount
    ) private {
        _increaseInternalBalance(recipient, _translateToIERC20(asset), amount);
        _receiveAsset(asset, amount, sender, false);
    }
    function _withdrawFromInternalBalance(
        IAsset asset,
        address sender,
        address payable recipient,
        uint256 amount
    ) private {
        // A partial decrease of Internal Balance is disallowed: `sender` must have the full `amount`.
        _decreaseInternalBalance(sender, _translateToIERC20(asset), amount, false);
        _sendAsset(asset, amount, recipient, false);
    }
    function _transferInternalBalance(
        IERC20 token,
        address sender,
        address recipient,
        uint256 amount
    ) private {
        // A partial decrease of Internal Balance is disallowed: `sender` must have the full `amount`.
        _decreaseInternalBalance(sender, token, amount, false);
        _increaseInternalBalance(recipient, token, amount);
    }
    function _transferToExternalBalance(
        IERC20 token,
        address sender,
        address recipient,
        uint256 amount
    ) private {
        if (amount > 0) {
            token.safeTransferFrom(sender, recipient, amount);
            emit ExternalBalanceTransfer(token, sender, recipient, amount);
        }
    }
    /**
     * @dev Increases `account`'s Internal Balance for `token` by `amount`.
     */
    function _increaseInternalBalance(
        address account,
        IERC20 token,
        uint256 amount
    ) internal override {
        uint256 currentBalance = _getInternalBalance(account, token);
        uint256 newBalance = currentBalance.add(amount);
        _setInternalBalance(account, token, newBalance, amount.toInt256());
    }
    /**
     * @dev Decreases `account`'s Internal Balance for `token` by `amount`. If `allowPartial` is true, this function
     * doesn't revert if `account` doesn't have enough balance, and sets it to zero and returns the deducted amount
     * instead.
     */
    function _decreaseInternalBalance(
        address account,
        IERC20 token,
        uint256 amount,
        bool allowPartial
    ) internal override returns (uint256 deducted) {
        uint256 currentBalance = _getInternalBalance(account, token);
        _require(allowPartial || (currentBalance >= amount), Errors.INSUFFICIENT_INTERNAL_BALANCE);
        deducted = Math.min(currentBalance, amount);
        // By construction, `deducted` is lower or equal to `currentBalance`, so we don't need to use checked
        // arithmetic.
        uint256 newBalance = currentBalance - deducted;
        _setInternalBalance(account, token, newBalance, -(deducted.toInt256()));
    }
    /**
     * @dev Sets `account`'s Internal Balance for `token` to `newBalance`.
     *
     * Emits an `InternalBalanceChanged` event. This event includes `delta`, which is the amount the balance increased
     * (if positive) or decreased (if negative). To avoid reading the current balance in order to compute the delta,
     * this function relies on the caller providing it directly.
     */
    function _setInternalBalance(
        address account,
        IERC20 token,
        uint256 newBalance,
        int256 delta
    ) private {
        _internalTokenBalance[account][token] = newBalance;
        emit InternalBalanceChanged(account, token, delta);
    }
    /**
     * @dev Returns `account`'s Internal Balance for `token`.
     */
    function _getInternalBalance(address account, IERC20 token) internal view returns (uint256) {
        return _internalTokenBalance[account][token];
    }
    /**
     * @dev Destructures a User Balance operation, validating that the contract caller is allowed to perform it.
     */
    function _validateUserBalanceOp(UserBalanceOp memory op, bool checkedCallerIsRelayer)
        private
        view
        returns (
            UserBalanceOpKind,
            IAsset,
            uint256,
            address,
            address payable,
            bool
        )
    {
        // The only argument we need to validate is `sender`, which can only be either the contract caller, or a
        // relayer approved by `sender`.
        address sender = op.sender;
        if (sender != msg.sender) {
            // We need to check both that the contract caller is a relayer, and that `sender` approved them.
            // Because the relayer check is global (i.e. independent of `sender`), we cache that result and skip it for
            // other operations in this same transaction (if any).
            if (!checkedCallerIsRelayer) {
                _authenticateCaller();
                checkedCallerIsRelayer = true;
            }
            _require(_hasApprovedRelayer(sender, msg.sender), Errors.USER_DOESNT_ALLOW_RELAYER);
        }
        return (op.kind, op.asset, op.amount, sender, op.recipient, checkedCallerIsRelayer);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "./IVault.sol";
import "./IPoolSwapStructs.sol";
/**
 * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
 * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
 * either IGeneralPool or IMinimalSwapInfoPool
 */
interface IBasePool is IPoolSwapStructs {
    /**
     * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
     * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
     * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
     * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
     *
     * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
     *
     * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
     * designated to receive any benefits (typically pool shares). `currentBalances` contains the total balances
     * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
     *
     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
     * balance.
     *
     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
     * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
     *
     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
     * state-changing operations, such as minting pool shares.
     */
    function onJoinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);
    /**
     * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
     * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
     * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
     * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
     * `protocolSwapFeePercentage`.
     *
     * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
     *
     * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
     * to which the Vault will send the proceeds. `currentBalances` contains the total token balances for each token
     * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
     *
     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
     * balance.
     *
     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
     * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
     *
     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
     * state-changing operations, such as burning pool shares.
     */
    function onExitPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/math/Math.sol";
import "../lib/helpers/BalancerErrors.sol";
import "../lib/helpers/InputHelpers.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "./UserBalance.sol";
import "./balances/BalanceAllocation.sol";
import "./balances/GeneralPoolsBalance.sol";
import "./balances/MinimalSwapInfoPoolsBalance.sol";
import "./balances/TwoTokenPoolsBalance.sol";
abstract contract AssetManagers is
    ReentrancyGuard,
    GeneralPoolsBalance,
    MinimalSwapInfoPoolsBalance,
    TwoTokenPoolsBalance
{
    using Math for uint256;
    using SafeERC20 for IERC20;
    // Stores the Asset Manager for each token of each Pool.
    mapping(bytes32 => mapping(IERC20 => address)) internal _poolAssetManagers;
    function managePoolBalance(PoolBalanceOp[] memory ops) external override nonReentrant whenNotPaused {
        // This variable could be declared inside the loop, but that causes the compiler to allocate memory on each
        // loop iteration, increasing gas costs.
        PoolBalanceOp memory op;
        for (uint256 i = 0; i < ops.length; ++i) {
            // By indexing the array only once, we don't spend extra gas in the same bounds check.
            op = ops[i];
            bytes32 poolId = op.poolId;
            _ensureRegisteredPool(poolId);
            IERC20 token = op.token;
            _require(_isTokenRegistered(poolId, token), Errors.TOKEN_NOT_REGISTERED);
            _require(_poolAssetManagers[poolId][token] == msg.sender, Errors.SENDER_NOT_ASSET_MANAGER);
            PoolBalanceOpKind kind = op.kind;
            uint256 amount = op.amount;
            (int256 cashDelta, int256 managedDelta) = _performPoolManagementOperation(kind, poolId, token, amount);
            emit PoolBalanceManaged(poolId, msg.sender, token, cashDelta, managedDelta);
        }
    }
    /**
     * @dev Performs the `kind` Asset Manager operation on a Pool.
     *
     * Withdrawals will transfer `amount` tokens to the caller, deposits will transfer `amount` tokens from the caller,
     * and updates will set the managed balance to `amount`.
     *
     * Returns a tuple with the 'cash' and 'managed' balance deltas as a result of this call.
     */
    function _performPoolManagementOperation(
        PoolBalanceOpKind kind,
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) private returns (int256, int256) {
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (kind == PoolBalanceOpKind.WITHDRAW) {
            return _withdrawPoolBalance(poolId, specialization, token, amount);
        } else if (kind == PoolBalanceOpKind.DEPOSIT) {
            return _depositPoolBalance(poolId, specialization, token, amount);
        } else {
            // PoolBalanceOpKind.UPDATE
            return _updateManagedBalance(poolId, specialization, token, amount);
        }
    }
    /**
     * @dev Moves `amount` tokens from a Pool's 'cash' to 'managed' balance, and transfers them to the caller.
     *
     * Returns the 'cash' and 'managed' balance deltas as a result of this call, which will be complementary.
     */
    function _withdrawPoolBalance(
        bytes32 poolId,
        PoolSpecialization specialization,
        IERC20 token,
        uint256 amount
    ) private returns (int256 cashDelta, int256 managedDelta) {
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            _twoTokenPoolCashToManaged(poolId, token, amount);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            _minimalSwapInfoPoolCashToManaged(poolId, token, amount);
        } else {
            // PoolSpecialization.GENERAL
            _generalPoolCashToManaged(poolId, token, amount);
        }
        if (amount > 0) {
            token.safeTransfer(msg.sender, amount);
        }
        // Since 'cash' and 'managed' are stored as uint112, `amount` is guaranteed to also fit in 112 bits. It will
        // therefore always fit in a 256 bit integer.
        cashDelta = int256(-amount);
        managedDelta = int256(amount);
    }
    /**
     * @dev Moves `amount` tokens from a Pool's 'managed' to 'cash' balance, and transfers them from the caller.
     *
     * Returns the 'cash' and 'managed' balance deltas as a result of this call, which will be complementary.
     */
    function _depositPoolBalance(
        bytes32 poolId,
        PoolSpecialization specialization,
        IERC20 token,
        uint256 amount
    ) private returns (int256 cashDelta, int256 managedDelta) {
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            _twoTokenPoolManagedToCash(poolId, token, amount);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            _minimalSwapInfoPoolManagedToCash(poolId, token, amount);
        } else {
            // PoolSpecialization.GENERAL
            _generalPoolManagedToCash(poolId, token, amount);
        }
        if (amount > 0) {
            token.safeTransferFrom(msg.sender, address(this), amount);
        }
        // Since 'cash' and 'managed' are stored as uint112, `amount` is guaranteed to also fit in 112 bits. It will
        // therefore always fit in a 256 bit integer.
        cashDelta = int256(amount);
        managedDelta = int256(-amount);
    }
    /**
     * @dev Sets a Pool's 'managed' balance to `amount`.
     *
     * Returns the 'cash' and 'managed' balance deltas as a result of this call (the 'cash' delta will always be zero).
     */
    function _updateManagedBalance(
        bytes32 poolId,
        PoolSpecialization specialization,
        IERC20 token,
        uint256 amount
    ) private returns (int256 cashDelta, int256 managedDelta) {
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            managedDelta = _setTwoTokenPoolManagedBalance(poolId, token, amount);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            managedDelta = _setMinimalSwapInfoPoolManagedBalance(poolId, token, amount);
        } else {
            // PoolSpecialization.GENERAL
            managedDelta = _setGeneralPoolManagedBalance(poolId, token, amount);
        }
        cashDelta = 0;
    }
    /**
     * @dev Returns true if `token` is registered for `poolId`.
     */
    function _isTokenRegistered(bytes32 poolId, IERC20 token) private view returns (bool) {
        PoolSpecialization specialization = _getPoolSpecialization(poolId);
        if (specialization == PoolSpecialization.TWO_TOKEN) {
            return _isTwoTokenPoolTokenRegistered(poolId, token);
        } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
            return _isMinimalSwapInfoPoolTokenRegistered(poolId, token);
        } else {
            // PoolSpecialization.GENERAL
            return _isGeneralPoolTokenRegistered(poolId, token);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/helpers/BalancerErrors.sol";
import "../lib/openzeppelin/ReentrancyGuard.sol";
import "./VaultAuthorization.sol";
/**
 * @dev Maintains the Pool ID data structure, implements Pool ID creation and registration, and defines useful modifiers
 * and helper functions for ensuring correct behavior when working with Pools.
 */
abstract contract PoolRegistry is ReentrancyGuard, VaultAuthorization {
    // Each pool is represented by their unique Pool ID. We use `bytes32` for them, for lack of a way to define new
    // types.
    mapping(bytes32 => bool) private _isPoolRegistered;
    // We keep an increasing nonce to make Pool IDs unique. It is interpreted as a `uint80`, but storing it as a
    // `uint256` results in reduced bytecode on reads and writes due to the lack of masking.
    uint256 private _nextPoolNonce;
    /**
     * @dev Reverts unless `poolId` corresponds to a registered Pool.
     */
    modifier withRegisteredPool(bytes32 poolId) {
        _ensureRegisteredPool(poolId);
        _;
    }
    /**
     * @dev Reverts unless `poolId` corresponds to a registered Pool, and the caller is the Pool's contract.
     */
    modifier onlyPool(bytes32 poolId) {
        _ensurePoolIsSender(poolId);
        _;
    }
    /**
     * @dev Reverts unless `poolId` corresponds to a registered Pool.
     */
    function _ensureRegisteredPool(bytes32 poolId) internal view {
        _require(_isPoolRegistered[poolId], Errors.INVALID_POOL_ID);
    }
    /**
     * @dev Reverts unless `poolId` corresponds to a registered Pool, and the caller is the Pool's contract.
     */
    function _ensurePoolIsSender(bytes32 poolId) private view {
        _ensureRegisteredPool(poolId);
        _require(msg.sender == _getPoolAddress(poolId), Errors.CALLER_NOT_POOL);
    }
    function registerPool(PoolSpecialization specialization)
        external
        override
        nonReentrant
        whenNotPaused
        returns (bytes32)
    {
        // Each Pool is assigned a unique ID based on an incrementing nonce. This assumes there will never be more than
        // 2**80 Pools, and the nonce will not overflow.
        bytes32 poolId = _toPoolId(msg.sender, specialization, uint80(_nextPoolNonce));
        _require(!_isPoolRegistered[poolId], Errors.INVALID_POOL_ID); // Should never happen as Pool IDs are unique.
        _isPoolRegistered[poolId] = true;
        _nextPoolNonce += 1;
        // Note that msg.sender is the pool's contract
        emit PoolRegistered(poolId, msg.sender, specialization);
        return poolId;
    }
    function getPool(bytes32 poolId)
        external
        view
        override
        withRegisteredPool(poolId)
        returns (address, PoolSpecialization)
    {
        return (_getPoolAddress(poolId), _getPoolSpecialization(poolId));
    }
    /**
     * @dev Creates a Pool ID.
     *
     * These are deterministically created by packing the Pool's contract address and its specialization setting into
     * the ID. This saves gas by making this data easily retrievable from a Pool ID with no storage accesses.
     *
     * Since a single contract can register multiple Pools, a unique nonce must be provided to ensure Pool IDs are
     * unique.
     *
     * Pool IDs have the following layout:
     * | 20 bytes pool contract address | 2 bytes specialization setting | 10 bytes nonce |
     * MSB                                                                              LSB
     *
     * 2 bytes for the specialization setting is a bit overkill: there only three of them, which means two bits would
     * suffice. However, there's nothing else of interest to store in this extra space.
     */
    function _toPoolId(
        address pool,
        PoolSpecialization specialization,
        uint80 nonce
    ) internal pure returns (bytes32) {
        bytes32 serialized;
        serialized |= bytes32(uint256(nonce));
        serialized |= bytes32(uint256(specialization)) << (10 * 8);
        serialized |= bytes32(uint256(pool)) << (12 * 8);
        return serialized;
    }
    /**
     * @dev Returns the address of a Pool's contract.
     *
     * Due to how Pool IDs are created, this is done with no storage accesses and costs little gas.
     */
    function _getPoolAddress(bytes32 poolId) internal pure returns (address) {
        // 12 byte logical shift left to remove the nonce and specialization setting. We don't need to mask,
        // since the logical shift already sets the upper bits to zero.
        return address(uint256(poolId) >> (12 * 8));
    }
    /**
     * @dev Returns the specialization setting of a Pool.
     *
     * Due to how Pool IDs are created, this is done with no storage accesses and costs little gas.
     */
    function _getPoolSpecialization(bytes32 poolId) internal pure returns (PoolSpecialization specialization) {
        // 10 byte logical shift left to remove the nonce, followed by a 2 byte mask to remove the address.
        uint256 value = uint256(poolId >> (10 * 8)) & (2**(2 * 8) - 1);
        // Casting a value into an enum results in a runtime check that reverts unless the value is within the enum's
        // range. Passing an invalid Pool ID to this function would then result in an obscure revert with no reason
        // string: we instead perform the check ourselves to help in error diagnosis.
        // There are three Pool specialization settings: general, minimal swap info and two tokens, which correspond to
        // values 0, 1 and 2.
        _require(value < 3, Errors.INVALID_POOL_ID);
        // Because we have checked that `value` is within the enum range, we can use assembly to skip the runtime check.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            specialization := value
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../../lib/helpers/BalancerErrors.sol";
import "../../lib/openzeppelin/EnumerableMap.sol";
import "../../lib/openzeppelin/IERC20.sol";
import "./BalanceAllocation.sol";
abstract contract GeneralPoolsBalance {
    using BalanceAllocation for bytes32;
    using EnumerableMap for EnumerableMap.IERC20ToBytes32Map;
    // Data for Pools with the General specialization setting
    //
    // These Pools use the IGeneralPool interface, which means the Vault must query the balance for *all* of their
    // tokens in every swap. If we kept a mapping of token to balance plus a set (array) of tokens, it'd be very gas
    // intensive to read all token addresses just to then do a lookup on the balance mapping.
    //
    // Instead, we use our customized EnumerableMap, which lets us read the N balances in N+1 storage accesses (one for
    // each token in the Pool), access the index of any 'token in' a single read (required for the IGeneralPool call),
    // and update an entry's value given its index.
    // Map of token -> balance pairs for each Pool with this specialization. Many functions rely on storage pointers to
    // a Pool's EnumerableMap to save gas when computing storage slots.
    mapping(bytes32 => EnumerableMap.IERC20ToBytes32Map) internal _generalPoolsBalances;
    /**
     * @dev Registers a list of tokens in a General Pool.
     *
     * This function assumes `poolId` exists and corresponds to the General specialization setting.
     *
     * Requirements:
     *
     * - `tokens` must not be registered in the Pool
     * - `tokens` must not contain duplicates
     */
    function _registerGeneralPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        for (uint256 i = 0; i < tokens.length; ++i) {
            // EnumerableMaps require an explicit initial value when creating a key-value pair: we use zero, the same
            // value that is found in uninitialized storage, which corresponds to an empty balance.
            bool added = poolBalances.set(tokens[i], 0);
            _require(added, Errors.TOKEN_ALREADY_REGISTERED);
        }
    }
    /**
     * @dev Deregisters a list of tokens in a General Pool.
     *
     * This function assumes `poolId` exists and corresponds to the General specialization setting.
     *
     * Requirements:
     *
     * - `tokens` must be registered in the Pool
     * - `tokens` must have zero balance in the Vault
     * - `tokens` must not contain duplicates
     */
    function _deregisterGeneralPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        for (uint256 i = 0; i < tokens.length; ++i) {
            IERC20 token = tokens[i];
            bytes32 currentBalance = _getGeneralPoolBalance(poolBalances, token);
            _require(currentBalance.isZero(), Errors.NONZERO_TOKEN_BALANCE);
            // We don't need to check remove's return value, since _getGeneralPoolBalance already checks that the token
            // was registered.
            poolBalances.remove(token);
        }
    }
    /**
     * @dev Sets the balances of a General Pool's tokens to `balances`.
     *
     * WARNING: this assumes `balances` has the same length and order as the Pool's tokens.
     */
    function _setGeneralPoolBalances(bytes32 poolId, bytes32[] memory balances) internal {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        for (uint256 i = 0; i < balances.length; ++i) {
            // Since we assume all balances are properly ordered, we can simply use `unchecked_setAt` to avoid one less
            // storage read per token.
            poolBalances.unchecked_setAt(i, balances[i]);
        }
    }
    /**
     * @dev Transforms `amount` of `token`'s balance in a General Pool from cash into managed.
     *
     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
     * registered for that Pool.
     */
    function _generalPoolCashToManaged(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal {
        _updateGeneralPoolBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
    }
    /**
     * @dev Transforms `amount` of `token`'s balance in a General Pool from managed into cash.
     *
     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
     * registered for that Pool.
     */
    function _generalPoolManagedToCash(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal {
        _updateGeneralPoolBalance(poolId, token, BalanceAllocation.managedToCash, amount);
    }
    /**
     * @dev Sets `token`'s managed balance in a General Pool to `amount`.
     *
     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
     * registered for that Pool.
     *
     * Returns the managed balance delta as a result of this call.
     */
    function _setGeneralPoolManagedBalance(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal returns (int256) {
        return _updateGeneralPoolBalance(poolId, token, BalanceAllocation.setManaged, amount);
    }
    /**
     * @dev Sets `token`'s balance in a General Pool to the result of the `mutation` function when called with the
     * current balance and `amount`.
     *
     * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
     * registered for that Pool.
     *
     * Returns the managed balance delta as a result of this call.
     */
    function _updateGeneralPoolBalance(
        bytes32 poolId,
        IERC20 token,
        function(bytes32, uint256) returns (bytes32) mutation,
        uint256 amount
    ) private returns (int256) {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        bytes32 currentBalance = _getGeneralPoolBalance(poolBalances, token);
        bytes32 newBalance = mutation(currentBalance, amount);
        poolBalances.set(token, newBalance);
        return newBalance.managedDelta(currentBalance);
    }
    /**
     * @dev Returns an array with all the tokens and balances in a General Pool. The order may change when tokens are
     * registered or deregistered.
     *
     * This function assumes `poolId` exists and corresponds to the General specialization setting.
     */
    function _getGeneralPoolTokens(bytes32 poolId)
        internal
        view
        returns (IERC20[] memory tokens, bytes32[] memory balances)
    {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        tokens = new IERC20[](poolBalances.length());
        balances = new bytes32[](tokens.length);
        for (uint256 i = 0; i < tokens.length; ++i) {
            // Because the iteration is bounded by `tokens.length`, which matches the EnumerableMap's length, we can use
            // `unchecked_at` as we know `i` is a valid token index, saving storage reads.
            (tokens[i], balances[i]) = poolBalances.unchecked_at(i);
        }
    }
    /**
     * @dev Returns the balance of a token in a General Pool.
     *
     * This function assumes `poolId` exists and corresponds to the General specialization setting.
     *
     * Requirements:
     *
     * - `token` must be registered in the Pool
     */
    function _getGeneralPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        return _getGeneralPoolBalance(poolBalances, token);
    }
    /**
     * @dev Same as `_getGeneralPoolBalance` but using a Pool's storage pointer, which saves gas in repeated reads and
     * writes.
     */
    function _getGeneralPoolBalance(EnumerableMap.IERC20ToBytes32Map storage poolBalances, IERC20 token)
        private
        view
        returns (bytes32)
    {
        return poolBalances.get(token, Errors.TOKEN_NOT_REGISTERED);
    }
    /**
     * @dev Returns true if `token` is registered in a General Pool.
     *
     * This function assumes `poolId` exists and corresponds to the General specialization setting.
     */
    function _isGeneralPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
        EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
        return poolBalances.contains(token);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../../lib/helpers/BalancerErrors.sol";
import "../../lib/openzeppelin/EnumerableSet.sol";
import "../../lib/openzeppelin/IERC20.sol";
import "./BalanceAllocation.sol";
import "../PoolRegistry.sol";
abstract contract MinimalSwapInfoPoolsBalance is PoolRegistry {
    using BalanceAllocation for bytes32;
    using EnumerableSet for EnumerableSet.AddressSet;
    // Data for Pools with the Minimal Swap Info specialization setting
    //
    // These Pools use the IMinimalSwapInfoPool interface, and so the Vault must read the balance of the two tokens
    // in the swap. The best solution is to use a mapping from token to balance, which lets us read or write any token's
    // balance in a single storage access.
    //
    // We also keep a set of registered tokens. Because tokens with non-zero balance are by definition registered, in
    // some balance getters we skip checking for token registration if a non-zero balance is found, saving gas by
    // performing a single read instead of two.
    mapping(bytes32 => mapping(IERC20 => bytes32)) internal _minimalSwapInfoPoolsBalances;
    mapping(bytes32 => EnumerableSet.AddressSet) internal _minimalSwapInfoPoolsTokens;
    /**
     * @dev Registers a list of tokens in a Minimal Swap Info Pool.
     *
     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
     *
     * Requirements:
     *
     * - `tokens` must not be registered in the Pool
     * - `tokens` must not contain duplicates
     */
    function _registerMinimalSwapInfoPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
        for (uint256 i = 0; i < tokens.length; ++i) {
            bool added = poolTokens.add(address(tokens[i]));
            _require(added, Errors.TOKEN_ALREADY_REGISTERED);
            // Note that we don't initialize the balance mapping: the default value of zero corresponds to an empty
            // balance.
        }
    }
    /**
     * @dev Deregisters a list of tokens in a Minimal Swap Info Pool.
     *
     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
     *
     * Requirements:
     *
     * - `tokens` must be registered in the Pool
     * - `tokens` must have zero balance in the Vault
     * - `tokens` must not contain duplicates
     */
    function _deregisterMinimalSwapInfoPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
        for (uint256 i = 0; i < tokens.length; ++i) {
            IERC20 token = tokens[i];
            _require(_minimalSwapInfoPoolsBalances[poolId][token].isZero(), Errors.NONZERO_TOKEN_BALANCE);
            // For consistency with other Pool specialization settings, we explicitly reset the balance (which may have
            // a non-zero last change block).
            delete _minimalSwapInfoPoolsBalances[poolId][token];
            bool removed = poolTokens.remove(address(token));
            _require(removed, Errors.TOKEN_NOT_REGISTERED);
        }
    }
    /**
     * @dev Sets the balances of a Minimal Swap Info Pool's tokens to `balances`.
     *
     * WARNING: this assumes `balances` has the same length and order as the Pool's tokens.
     */
    function _setMinimalSwapInfoPoolBalances(
        bytes32 poolId,
        IERC20[] memory tokens,
        bytes32[] memory balances
    ) internal {
        for (uint256 i = 0; i < tokens.length; ++i) {
            _minimalSwapInfoPoolsBalances[poolId][tokens[i]] = balances[i];
        }
    }
    /**
     * @dev Transforms `amount` of `token`'s balance in a Minimal Swap Info Pool from cash into managed.
     *
     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
     * `token` is registered for that Pool.
     */
    function _minimalSwapInfoPoolCashToManaged(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal {
        _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
    }
    /**
     * @dev Transforms `amount` of `token`'s balance in a Minimal Swap Info Pool from managed into cash.
     *
     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
     * `token` is registered for that Pool.
     */
    function _minimalSwapInfoPoolManagedToCash(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal {
        _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.managedToCash, amount);
    }
    /**
     * @dev Sets `token`'s managed balance in a Minimal Swap Info Pool to `amount`.
     *
     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
     * `token` is registered for that Pool.
     *
     * Returns the managed balance delta as a result of this call.
     */
    function _setMinimalSwapInfoPoolManagedBalance(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal returns (int256) {
        return _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.setManaged, amount);
    }
    /**
     * @dev Sets `token`'s balance in a Minimal Swap Info Pool to the result of the `mutation` function when called with
     * the current balance and `amount`.
     *
     * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
     * `token` is registered for that Pool.
     *
     * Returns the managed balance delta as a result of this call.
     */
    function _updateMinimalSwapInfoPoolBalance(
        bytes32 poolId,
        IERC20 token,
        function(bytes32, uint256) returns (bytes32) mutation,
        uint256 amount
    ) internal returns (int256) {
        bytes32 currentBalance = _getMinimalSwapInfoPoolBalance(poolId, token);
        bytes32 newBalance = mutation(currentBalance, amount);
        _minimalSwapInfoPoolsBalances[poolId][token] = newBalance;
        return newBalance.managedDelta(currentBalance);
    }
    /**
     * @dev Returns an array with all the tokens and balances in a Minimal Swap Info Pool. The order may change when
     * tokens are registered or deregistered.
     *
     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
     */
    function _getMinimalSwapInfoPoolTokens(bytes32 poolId)
        internal
        view
        returns (IERC20[] memory tokens, bytes32[] memory balances)
    {
        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
        tokens = new IERC20[](poolTokens.length());
        balances = new bytes32[](tokens.length);
        for (uint256 i = 0; i < tokens.length; ++i) {
            // Because the iteration is bounded by `tokens.length`, which matches the EnumerableSet's length, we can use
            // `unchecked_at` as we know `i` is a valid token index, saving storage reads.
            IERC20 token = IERC20(poolTokens.unchecked_at(i));
            tokens[i] = token;
            balances[i] = _minimalSwapInfoPoolsBalances[poolId][token];
        }
    }
    /**
     * @dev Returns the balance of a token in a Minimal Swap Info Pool.
     *
     * Requirements:
     *
     * - `poolId` must be a Minimal Swap Info Pool
     * - `token` must be registered in the Pool
     */
    function _getMinimalSwapInfoPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
        bytes32 balance = _minimalSwapInfoPoolsBalances[poolId][token];
        // A non-zero balance guarantees that the token is registered. If zero, we manually check if the token is
        // registered in the Pool. Token registration implies that the Pool is registered as well, which lets us save
        // gas by not performing the check.
        bool tokenRegistered = balance.isNotZero() || _minimalSwapInfoPoolsTokens[poolId].contains(address(token));
        if (!tokenRegistered) {
            // The token might not be registered because the Pool itself is not registered. We check this to provide a
            // more accurate revert reason.
            _ensureRegisteredPool(poolId);
            _revert(Errors.TOKEN_NOT_REGISTERED);
        }
        return balance;
    }
    /**
     * @dev Returns true if `token` is registered in a Minimal Swap Info Pool.
     *
     * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
     */
    function _isMinimalSwapInfoPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
        EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
        return poolTokens.contains(address(token));
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../../lib/helpers/BalancerErrors.sol";
import "../../lib/openzeppelin/IERC20.sol";
import "./BalanceAllocation.sol";
import "../PoolRegistry.sol";
abstract contract TwoTokenPoolsBalance is PoolRegistry {
    using BalanceAllocation for bytes32;
    // Data for Pools with the Two Token specialization setting
    //
    // These are similar to the Minimal Swap Info Pool case (because the Pool only has two tokens, and therefore there
    // are only two balances to read), but there's a key difference in how data is stored. Keeping a set makes little
    // sense, as it will only ever hold two tokens, so we can just store those two directly.
    //
    // The gas savings associated with using these Pools come from how token balances are stored: cash amounts for token
    // A and token B are packed together, as are managed amounts. Because only cash changes in a swap, there's no need
    // to write to this second storage slot. A single last change block number for both tokens is stored with the packed
    // cash fields.
    struct TwoTokenPoolBalances {
        bytes32 sharedCash;
        bytes32 sharedManaged;
    }
    // We could just keep a mapping from Pool ID to TwoTokenSharedBalances, but there's an issue: we wouldn't know to
    // which tokens those balances correspond. This would mean having to also check which are registered with the Pool.
    //
    // What we do instead to save those storage reads is keep a nested mapping from the token pair hash to the balances
    // struct. The Pool only has two tokens, so only a single entry of this mapping is set (the one that corresponds to
    // that pair's hash).
    //
    // This has the trade-off of making Vault code that interacts with these Pools cumbersome: both balances must be
    // accessed at the same time by using both token addresses, and some logic is needed to determine how the pair hash
    // is computed. We do this by sorting the tokens, calling the token with the lowest numerical address value token A,
    // and the other one token B. In functions where the token arguments could be either A or B, we use X and Y instead.
    //
    // If users query a token pair containing an unregistered token, the Pool will generate a hash for a mapping entry
    // that was not set, and return zero balances. Non-zero balances are only possible if both tokens in the pair
    // are registered with the Pool, which means we don't have to check the TwoTokenPoolTokens struct, and can save
    // storage reads.
    struct TwoTokenPoolTokens {
        IERC20 tokenA;
        IERC20 tokenB;
        mapping(bytes32 => TwoTokenPoolBalances) balances;
    }
    mapping(bytes32 => TwoTokenPoolTokens) private _twoTokenPoolTokens;
    /**
     * @dev Registers tokens in a Two Token Pool.
     *
     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
     *
     * Requirements:
     *
     * - `tokenX` and `tokenY` must not be the same
     * - The tokens must be ordered: tokenX < tokenY
     */
    function _registerTwoTokenPoolTokens(
        bytes32 poolId,
        IERC20 tokenX,
        IERC20 tokenY
    ) internal {
        // Not technically true since we didn't register yet, but this is consistent with the error messages of other
        // specialization settings.
        _require(tokenX != tokenY, Errors.TOKEN_ALREADY_REGISTERED);
        _require(tokenX < tokenY, Errors.UNSORTED_TOKENS);
        // A Two Token Pool with no registered tokens is identified by having zero addresses for tokens A and B.
        TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
        _require(poolTokens.tokenA == IERC20(0) && poolTokens.tokenB == IERC20(0), Errors.TOKENS_ALREADY_SET);
        // Since tokenX < tokenY, tokenX is A and tokenY is B
        poolTokens.tokenA = tokenX;
        poolTokens.tokenB = tokenY;
        // Note that we don't initialize the balance mapping: the default value of zero corresponds to an empty
        // balance.
    }
    /**
     * @dev Deregisters tokens in a Two Token Pool.
     *
     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
     *
     * Requirements:
     *
     * - `tokenX` and `tokenY` must be registered in the Pool
     * - both tokens must have zero balance in the Vault
     */
    function _deregisterTwoTokenPoolTokens(
        bytes32 poolId,
        IERC20 tokenX,
        IERC20 tokenY
    ) internal {
        (
            bytes32 balanceA,
            bytes32 balanceB,
            TwoTokenPoolBalances storage poolBalances
        ) = _getTwoTokenPoolSharedBalances(poolId, tokenX, tokenY);
        _require(balanceA.isZero() && balanceB.isZero(), Errors.NONZERO_TOKEN_BALANCE);
        delete _twoTokenPoolTokens[poolId];
        // For consistency with other Pool specialization settings, we explicitly reset the packed cash field (which may
        // have a non-zero last change block).
        delete poolBalances.sharedCash;
    }
    /**
     * @dev Sets the cash balances of a Two Token Pool's tokens.
     *
     * WARNING: this assumes `tokenA` and `tokenB` are the Pool's two registered tokens, and are in the correct order.
     */
    function _setTwoTokenPoolCashBalances(
        bytes32 poolId,
        IERC20 tokenA,
        bytes32 balanceA,
        IERC20 tokenB,
        bytes32 balanceB
    ) internal {
        bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
        TwoTokenPoolBalances storage poolBalances = _twoTokenPoolTokens[poolId].balances[pairHash];
        poolBalances.sharedCash = BalanceAllocation.toSharedCash(balanceA, balanceB);
    }
    /**
     * @dev Transforms `amount` of `token`'s balance in a Two Token Pool from cash into managed.
     *
     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
     * registered for that Pool.
     */
    function _twoTokenPoolCashToManaged(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal {
        _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
    }
    /**
     * @dev Transforms `amount` of `token`'s balance in a Two Token Pool from managed into cash.
     *
     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
     * registered for that Pool.
     */
    function _twoTokenPoolManagedToCash(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal {
        _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.managedToCash, amount);
    }
    /**
     * @dev Sets `token`'s managed balance in a Two Token Pool to `amount`.
     *
     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
     * registered for that Pool.
     *
     * Returns the managed balance delta as a result of this call.
     */
    function _setTwoTokenPoolManagedBalance(
        bytes32 poolId,
        IERC20 token,
        uint256 amount
    ) internal returns (int256) {
        return _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.setManaged, amount);
    }
    /**
     * @dev Sets `token`'s balance in a Two Token Pool to the result of the `mutation` function when called with
     * the current balance and `amount`.
     *
     * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
     * registered for that Pool.
     *
     * Returns the managed balance delta as a result of this call.
     */
    function _updateTwoTokenPoolSharedBalance(
        bytes32 poolId,
        IERC20 token,
        function(bytes32, uint256) returns (bytes32) mutation,
        uint256 amount
    ) private returns (int256) {
        (
            TwoTokenPoolBalances storage balances,
            IERC20 tokenA,
            bytes32 balanceA,
            ,
            bytes32 balanceB
        ) = _getTwoTokenPoolBalances(poolId);
        int256 delta;
        if (token == tokenA) {
            bytes32 newBalance = mutation(balanceA, amount);
            delta = newBalance.managedDelta(balanceA);
            balanceA = newBalance;
        } else {
            // token == tokenB
            bytes32 newBalance = mutation(balanceB, amount);
            delta = newBalance.managedDelta(balanceB);
            balanceB = newBalance;
        }
        balances.sharedCash = BalanceAllocation.toSharedCash(balanceA, balanceB);
        balances.sharedManaged = BalanceAllocation.toSharedManaged(balanceA, balanceB);
        return delta;
    }
    /*
     * @dev Returns an array with all the tokens and balances in a Two Token Pool. The order may change when
     * tokens are registered or deregistered.
     *
     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
     */
    function _getTwoTokenPoolTokens(bytes32 poolId)
        internal
        view
        returns (IERC20[] memory tokens, bytes32[] memory balances)
    {
        (, IERC20 tokenA, bytes32 balanceA, IERC20 tokenB, bytes32 balanceB) = _getTwoTokenPoolBalances(poolId);
        // Both tokens will either be zero (if unregistered) or non-zero (if registered), but we keep the full check for
        // clarity.
        if (tokenA == IERC20(0) || tokenB == IERC20(0)) {
            return (new IERC20[](0), new bytes32[](0));
        }
        // Note that functions relying on this getter expect tokens to be properly ordered, so we use the (A, B)
        // ordering.
        tokens = new IERC20[](2);
        tokens[0] = tokenA;
        tokens[1] = tokenB;
        balances = new bytes32[](2);
        balances[0] = balanceA;
        balances[1] = balanceB;
    }
    /**
     * @dev Same as `_getTwoTokenPoolTokens`, except it returns the two tokens and balances directly instead of using
     * an array, as well as a storage pointer to the `TwoTokenPoolBalances` struct, which can be used to update it
     * without having to recompute the pair hash and storage slot.
     */
    function _getTwoTokenPoolBalances(bytes32 poolId)
        private
        view
        returns (
            TwoTokenPoolBalances storage poolBalances,
            IERC20 tokenA,
            bytes32 balanceA,
            IERC20 tokenB,
            bytes32 balanceB
        )
    {
        TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
        tokenA = poolTokens.tokenA;
        tokenB = poolTokens.tokenB;
        bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
        poolBalances = poolTokens.balances[pairHash];
        bytes32 sharedCash = poolBalances.sharedCash;
        bytes32 sharedManaged = poolBalances.sharedManaged;
        balanceA = BalanceAllocation.fromSharedToBalanceA(sharedCash, sharedManaged);
        balanceB = BalanceAllocation.fromSharedToBalanceB(sharedCash, sharedManaged);
    }
    /**
     * @dev Returns the balance of a token in a Two Token Pool.
     *
     * This function assumes `poolId` exists and corresponds to the General specialization setting.
     *
     * This function is convenient but not particularly gas efficient, and should be avoided during gas-sensitive
     * operations, such as swaps. For those, _getTwoTokenPoolSharedBalances provides a more flexible interface.
     *
     * Requirements:
     *
     * - `token` must be registered in the Pool
     */
    function _getTwoTokenPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
        // We can't just read the balance of token, because we need to know the full pair in order to compute the pair
        // hash and access the balance mapping. We therefore rely on `_getTwoTokenPoolBalances`.
        (, IERC20 tokenA, bytes32 balanceA, IERC20 tokenB, bytes32 balanceB) = _getTwoTokenPoolBalances(poolId);
        if (token == tokenA) {
            return balanceA;
        } else if (token == tokenB) {
            return balanceB;
        } else {
            _revert(Errors.TOKEN_NOT_REGISTERED);
        }
    }
    /**
     * @dev Returns the balance of the two tokens in a Two Token Pool.
     *
     * The returned balances are those of token A and token B, where token A is the lowest of token X and token Y, and
     * token B the other.
     *
     * This function also returns a storage pointer to the TwoTokenPoolBalances struct associated with the token pair,
     * which can be used to update it without having to recompute the pair hash and storage slot.
     *
     * Requirements:
     *
     * - `poolId` must be a Minimal Swap Info Pool
     * - `tokenX` and `tokenY` must be registered in the Pool
     */
    function _getTwoTokenPoolSharedBalances(
        bytes32 poolId,
        IERC20 tokenX,
        IERC20 tokenY
    )
        internal
        view
        returns (
            bytes32 balanceA,
            bytes32 balanceB,
            TwoTokenPoolBalances storage poolBalances
        )
    {
        (IERC20 tokenA, IERC20 tokenB) = _sortTwoTokens(tokenX, tokenY);
        bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
        poolBalances = _twoTokenPoolTokens[poolId].balances[pairHash];
        // Because we're reading balances using the pair hash, if either token X or token Y is not registered then
        // *both* balance entries will be zero.
        bytes32 sharedCash = poolBalances.sharedCash;
        bytes32 sharedManaged = poolBalances.sharedManaged;
        // A non-zero balance guarantees that both tokens are registered. If zero, we manually check whether each
        // token is registered in the Pool. Token registration implies that the Pool is registered as well, which
        // lets us save gas by not performing the check.
        bool tokensRegistered = sharedCash.isNotZero() ||
            sharedManaged.isNotZero() ||
            (_isTwoTokenPoolTokenRegistered(poolId, tokenA) && _isTwoTokenPoolTokenRegistered(poolId, tokenB));
        if (!tokensRegistered) {
            // The tokens might not be registered because the Pool itself is not registered. We check this to provide a
            // more accurate revert reason.
            _ensureRegisteredPool(poolId);
            _revert(Errors.TOKEN_NOT_REGISTERED);
        }
        balanceA = BalanceAllocation.fromSharedToBalanceA(sharedCash, sharedManaged);
        balanceB = BalanceAllocation.fromSharedToBalanceB(sharedCash, sharedManaged);
    }
    /**
     * @dev Returns true if `token` is registered in a Two Token Pool.
     *
     * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
     */
    function _isTwoTokenPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
        TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
        // The zero address can never be a registered token.
        return (token == poolTokens.tokenA || token == poolTokens.tokenB) && token != IERC20(0);
    }
    /**
     * @dev Returns the hash associated with a given token pair.
     */
    function _getTwoTokenPairHash(IERC20 tokenA, IERC20 tokenB) private pure returns (bytes32) {
        return keccak256(abi.encodePacked(tokenA, tokenB));
    }
    /**
     * @dev Sorts two tokens in ascending order, returning them as a (tokenA, tokenB) tuple.
     */
    function _sortTwoTokens(IERC20 tokenX, IERC20 tokenY) private pure returns (IERC20, IERC20) {
        return tokenX < tokenY ? (tokenX, tokenY) : (tokenY, tokenX);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../lib/math/Math.sol";
import "../lib/helpers/BalancerErrors.sol";
import "../lib/openzeppelin/IERC20.sol";
import "../lib/helpers/AssetHelpers.sol";
import "../lib/openzeppelin/SafeERC20.sol";
import "../lib/openzeppelin/Address.sol";
import "./interfaces/IWETH.sol";
import "./interfaces/IAsset.sol";
import "./interfaces/IVault.sol";
abstract contract AssetTransfersHandler is AssetHelpers {
    using SafeERC20 for IERC20;
    using Address for address payable;
    /**
     * @dev Receives `amount` of `asset` from `sender`. If `fromInternalBalance` is true, it first withdraws as much
     * as possible from Internal Balance, then transfers any remaining amount.
     *
     * If `asset` is ETH, `fromInternalBalance` must be false (as ETH cannot be held as internal balance), and the funds
     * will be wrapped into WETH.
     *
     * WARNING: this function does not check that the contract caller has actually supplied any ETH - it is up to the
     * caller of this function to check that this is true to prevent the Vault from using its own ETH (though the Vault
     * typically doesn't hold any).
     */
    function _receiveAsset(
        IAsset asset,
        uint256 amount,
        address sender,
        bool fromInternalBalance
    ) internal {
        if (amount == 0) {
            return;
        }
        if (_isETH(asset)) {
            _require(!fromInternalBalance, Errors.INVALID_ETH_INTERNAL_BALANCE);
            // The ETH amount to receive is deposited into the WETH contract, which will in turn mint WETH for
            // the Vault at a 1:1 ratio.
            // A check for this condition is also introduced by the compiler, but this one provides a revert reason.
            // Note we're checking for the Vault's total balance, *not* ETH sent in this transaction.
            _require(address(this).balance >= amount, Errors.INSUFFICIENT_ETH);
            _WETH().deposit{ value: amount }();
        } else {
            IERC20 token = _asIERC20(asset);
            if (fromInternalBalance) {
                // We take as many tokens from Internal Balance as possible: any remaining amounts will be transferred.
                uint256 deductedBalance = _decreaseInternalBalance(sender, token, amount, true);
                // Because `deductedBalance` will be always the lesser of the current internal balance
                // and the amount to decrease, it is safe to perform unchecked arithmetic.
                amount -= deductedBalance;
            }
            if (amount > 0) {
                token.safeTransferFrom(sender, address(this), amount);
            }
        }
    }
    /**
     * @dev Sends `amount` of `asset` to `recipient`. If `toInternalBalance` is true, the asset is deposited as Internal
     * Balance instead of being transferred.
     *
     * If `asset` is ETH, `toInternalBalance` must be false (as ETH cannot be held as internal balance), and the funds
     * are instead sent directly after unwrapping WETH.
     */
    function _sendAsset(
        IAsset asset,
        uint256 amount,
        address payable recipient,
        bool toInternalBalance
    ) internal {
        if (amount == 0) {
            return;
        }
        if (_isETH(asset)) {
            // Sending ETH is not as involved as receiving it: the only special behavior is it cannot be
            // deposited to Internal Balance.
            _require(!toInternalBalance, Errors.INVALID_ETH_INTERNAL_BALANCE);
            // First, the Vault withdraws deposited ETH from the WETH contract, by burning the same amount of WETH
            // from the Vault. This receipt will be handled by the Vault's `receive`.
            _WETH().withdraw(amount);
            // Then, the withdrawn ETH is sent to the recipient.
            recipient.sendValue(amount);
        } else {
            IERC20 token = _asIERC20(asset);
            if (toInternalBalance) {
                _increaseInternalBalance(recipient, token, amount);
            } else {
                token.safeTransfer(recipient, amount);
            }
        }
    }
    /**
     * @dev Returns excess ETH back to the contract caller, assuming `amountUsed` has been spent. Reverts
     * if the caller sent less ETH than `amountUsed`.
     *
     * Because the caller might not know exactly how much ETH a Vault action will require, they may send extra.
     * Note that this excess value is returned *to the contract caller* (msg.sender). If caller and e.g. swap sender are
     * not the same (because the caller is a relayer for the sender), then it is up to the caller to manage this
     * returned ETH.
     */
    function _handleRemainingEth(uint256 amountUsed) internal {
        _require(msg.value >= amountUsed, Errors.INSUFFICIENT_ETH);
        uint256 excess = msg.value - amountUsed;
        if (excess > 0) {
            msg.sender.sendValue(excess);
        }
    }
    /**
     * @dev Enables the Vault to receive ETH. This is required for it to be able to unwrap WETH, which sends ETH to the
     * caller.
     *
     * Any ETH sent to the Vault outside of the WETH unwrapping mechanism would be forever locked inside the Vault, so
     * we prevent that from happening. Other mechanisms used to send ETH to the Vault (such as being the recipient of an
     * ETH swap, Pool exit or withdrawal, contract self-destruction, or receiving the block mining reward) will result
     * in locked funds, but are not otherwise a security or soundness issue. This check only exists as an attempt to
     * prevent user error.
     */
    receive() external payable {
        _require(msg.sender == address(_WETH()), Errors.ETH_TRANSFER);
    }
    // This contract uses virtual internal functions instead of inheriting from the modules that implement them (in
    // this case UserBalance) in order to decouple it from the rest of the system and enable standalone testing by
    // implementing these with mocks.
    function _increaseInternalBalance(
        address account,
        IERC20 token,
        uint256 amount
    ) internal virtual;
    function _decreaseInternalBalance(
        address account,
        IERC20 token,
        uint256 amount,
        bool capped
    ) internal virtual returns (uint256);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../openzeppelin/IERC20.sol";
import "../../vault/interfaces/IAsset.sol";
import "../../vault/interfaces/IWETH.sol";
abstract contract AssetHelpers {
    // solhint-disable-next-line var-name-mixedcase
    IWETH private immutable _weth;
    // Sentinel value used to indicate WETH with wrapping/unwrapping semantics. The zero address is a good choice for
    // multiple reasons: it is cheap to pass as a calldata argument, it is a known invalid token and non-contract, and
    // it is an address Pools cannot register as a token.
    address private constant _ETH = address(0);
    constructor(IWETH weth) {
        _weth = weth;
    }
    // solhint-disable-next-line func-name-mixedcase
    function _WETH() internal view returns (IWETH) {
        return _weth;
    }
    /**
     * @dev Returns true if `asset` is the sentinel value that represents ETH.
     */
    function _isETH(IAsset asset) internal pure returns (bool) {
        return address(asset) == _ETH;
    }
    /**
     * @dev Translates `asset` into an equivalent IERC20 token address. If `asset` represents ETH, it will be translated
     * to the WETH contract.
     */
    function _translateToIERC20(IAsset asset) internal view returns (IERC20) {
        return _isETH(asset) ? _WETH() : _asIERC20(asset);
    }
    /**
     * @dev Same as `_translateToIERC20(IAsset)`, but for an entire array.
     */
    function _translateToIERC20(IAsset[] memory assets) internal view returns (IERC20[] memory) {
        IERC20[] memory tokens = new IERC20[](assets.length);
        for (uint256 i = 0; i < assets.length; ++i) {
            tokens[i] = _translateToIERC20(assets[i]);
        }
        return tokens;
    }
    /**
     * @dev Interprets `asset` as an IERC20 token. This function should only be called on `asset` if `_isETH` previously
     * returned false for it, that is, if `asset` is guaranteed not to be the ETH sentinel value.
     */
    function _asIERC20(IAsset asset) internal pure returns (IERC20) {
        return IERC20(address(asset));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../helpers/BalancerErrors.sol";
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        _require(address(this).balance >= amount, Errors.ADDRESS_INSUFFICIENT_BALANCE);
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        _require(success, Errors.ADDRESS_CANNOT_SEND_VALUE);
    }
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
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Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
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    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
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    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
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might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/utils/Context.sol';
import '@openzeppelin/contracts/access/Ownable.sol';
import '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
import './dependency/Permitable.sol';
import './interfaces/IAggregationExecutor.sol';
import './interfaces/IAggregationExecutor1Inch.sol';
import './libraries/TransferHelper.sol';
import './libraries/RevertReasonParser.sol';
contract MetaAggregationRouterV2 is Permitable, Ownable {
  using SafeERC20 for IERC20;
  address public immutable WETH;
  address private constant ETH_ADDRESS = address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
  uint256 private constant _PARTIAL_FILL = 0x01;
  uint256 private constant _REQUIRES_EXTRA_ETH = 0x02;
  uint256 private constant _SHOULD_CLAIM = 0x04;
  uint256 private constant _BURN_FROM_MSG_SENDER = 0x08;
  uint256 private constant _BURN_FROM_TX_ORIGIN = 0x10;
  uint256 private constant _SIMPLE_SWAP = 0x20;
  uint256 private constant _FEE_ON_DST = 0x40;
  uint256 private constant _FEE_IN_BPS = 0x80;
  uint256 private constant _APPROVE_FUND = 0x100;
  uint256 private constant BPS = 10000;
  mapping(address => bool) public isWhitelist;
  struct SwapDescriptionV2 {
    IERC20 srcToken;
    IERC20 dstToken;
    address[] srcReceivers; // transfer src token to these addresses, default
    uint256[] srcAmounts;
    address[] feeReceivers;
    uint256[] feeAmounts;
    address dstReceiver;
    uint256 amount;
    uint256 minReturnAmount;
    uint256 flags;
    bytes permit;
  }
  /// @dev  use for swapGeneric and swap to avoid stack too deep
  struct SwapExecutionParams {
    address callTarget; // call this address
    address approveTarget; // approve this address if _APPROVE_FUND set
    bytes targetData;
    SwapDescriptionV2 desc;
    bytes clientData;
  }
  struct SimpleSwapData {
    address[] firstPools;
    uint256[] firstSwapAmounts;
    bytes[] swapDatas;
    uint256 deadline;
    bytes destTokenFeeData;
  }
  event Swapped(
    address sender,
    IERC20 srcToken,
    IERC20 dstToken,
    address dstReceiver,
    uint256 spentAmount,
    uint256 returnAmount
  );
  event ClientData(bytes clientData);
  event Exchange(address pair, uint256 amountOut, address output);
  event Fee(address token, uint256 totalAmount, uint256 totalFee, address[] recipients, uint256[] amounts, bool isBps);
  constructor(address _WETH) {
    WETH = _WETH;
  }
  receive() external payable {}
  function rescueFunds(address token, uint256 amount) external onlyOwner {
    if (_isETH(IERC20(token))) {
      TransferHelper.safeTransferETH(msg.sender, amount);
    } else {
      TransferHelper.safeTransfer(token, msg.sender, amount);
    }
  }
  function updateWhitelist(address[] memory addr, bool[] memory value) external onlyOwner {
    require(addr.length == value.length);
    for (uint256 i; i < addr.length; ++i) {
      isWhitelist[addr[i]] = value[i];
    }
  }
  function swapGeneric(SwapExecutionParams calldata execution)
    external
    payable
    returns (uint256 returnAmount, uint256 gasUsed)
  {
    uint256 gasBefore = gasleft();
    require(isWhitelist[execution.callTarget], 'Address not whitelisted');
    if (execution.approveTarget != execution.callTarget && execution.approveTarget != address(0)) {
      require(isWhitelist[execution.approveTarget], 'Address not whitelisted');
    }
    SwapDescriptionV2 memory desc = execution.desc;
    require(desc.minReturnAmount > 0, 'Invalid min return amount');
    // if extra eth is needed, in case srcToken is ETH
    _collectExtraETHIfNeeded(desc);
    _permit(desc.srcToken, desc.amount, desc.permit);
    bool feeInBps = _flagsChecked(desc.flags, _FEE_IN_BPS);
    uint256 spentAmount;
    address dstReceiver = desc.dstReceiver == address(0) ? msg.sender : desc.dstReceiver;
    if (!_flagsChecked(desc.flags, _FEE_ON_DST)) {
      // fee on src token
      // take fee on srcToken
      // take fee and deduct total amount
      desc.amount = _takeFee(desc.srcToken, msg.sender, desc.feeReceivers, desc.feeAmounts, desc.amount, feeInBps);
      bool collected;
      if (!_isETH(desc.srcToken) && _flagsChecked(desc.flags, _SHOULD_CLAIM)) {
        (collected, desc.amount) = _collectTokenIfNeeded(desc, msg.sender, address(this));
      }
      _transferFromOrApproveTarget(msg.sender, execution.approveTarget, desc, collected);
      // execute swap
      (spentAmount, returnAmount) = _executeSwap(
        execution.callTarget,
        execution.targetData,
        desc,
        _isETH(desc.srcToken) ? desc.amount : 0,
        dstReceiver
      );
    } else {
      bool collected;
      if (!_isETH(desc.srcToken) && _flagsChecked(desc.flags, _SHOULD_CLAIM)) {
        (collected, desc.amount) = _collectTokenIfNeeded(desc, msg.sender, address(this));
      }
      uint256 initialDstReceiverBalance = _getBalance(desc.dstToken, dstReceiver);
      _transferFromOrApproveTarget(msg.sender, execution.approveTarget, desc, collected);
      // fee on dst token
      // router get dst token first
      (spentAmount, returnAmount) = _executeSwap(
        execution.callTarget,
        execution.targetData,
        desc,
        _isETH(desc.srcToken) ? msg.value : 0,
        address(this)
      );
      {
        // then take fee on dst token
        uint256 leftAmount = _takeFee(
          desc.dstToken,
          address(this),
          desc.feeReceivers,
          desc.feeAmounts,
          returnAmount,
          feeInBps
        );
        _doTransferERC20(desc.dstToken, address(this), dstReceiver, leftAmount);
      }
      returnAmount = _getBalance(desc.dstToken, dstReceiver) - initialDstReceiverBalance;
    }
    // check return amount
    _checkReturnAmount(spentAmount, returnAmount, desc);
    //revoke allowance
    if (!_isETH(desc.srcToken) && execution.approveTarget != address(0)) {
      desc.srcToken.safeApprove(execution.approveTarget, 0);
    }
    emit Swapped(msg.sender, desc.srcToken, desc.dstToken, dstReceiver, spentAmount, returnAmount);
    emit Exchange(execution.callTarget, returnAmount, _isETH(desc.dstToken) ? WETH : address(desc.dstToken));
    emit ClientData(execution.clientData);
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function swap(SwapExecutionParams calldata execution)
    external
    payable
    returns (uint256 returnAmount, uint256 gasUsed)
  {
    uint256 gasBefore = gasleft();
    SwapDescriptionV2 memory desc = execution.desc;
    require(desc.minReturnAmount > 0, 'Min return should not be 0');
    require(execution.targetData.length > 0, 'executorData should be not zero');
    // simple mode swap
    if (_flagsChecked(desc.flags, _SIMPLE_SWAP)) {
      return
        swapSimpleMode(IAggregationExecutor(execution.callTarget), desc, execution.targetData, execution.clientData);
    }
    _collectExtraETHIfNeeded(desc);
    _permit(desc.srcToken, desc.amount, desc.permit);
    bool feeInBps = _flagsChecked(desc.flags, _FEE_IN_BPS);
    uint256 spentAmount;
    address dstReceiver = desc.dstReceiver == address(0) ? msg.sender : desc.dstReceiver;
    if (!_flagsChecked(desc.flags, _FEE_ON_DST)) {
      // fee on src token
      {
        // take fee on srcToken
        // deduct total swap amount
        desc.amount = _takeFee(
          desc.srcToken,
          msg.sender,
          desc.feeReceivers,
          desc.feeAmounts,
          _isETH(desc.srcToken) ? msg.value : desc.amount,
          feeInBps
        );
        // transfer fund from msg.sender to our executor
        _transferFromOrApproveTarget(msg.sender, address(0), desc, false);
        // execute swap
        (spentAmount, returnAmount) = _executeSwap(
          execution.callTarget,
          abi.encodeWithSelector(IAggregationExecutor.callBytes.selector, execution.targetData),
          desc,
          _isETH(desc.srcToken) ? desc.amount : 0,
          dstReceiver
        );
      }
    } else {
      // fee on dst token
      // router get dst token first
      uint256 initialDstReceiverBalance = _getBalance(desc.dstToken, dstReceiver);
      // transfer fund from msg.sender to our executor
      _transferFromOrApproveTarget(msg.sender, address(0), desc, false);
      // swap to receive dstToken on this router
      (spentAmount, returnAmount) = _executeSwap(
        execution.callTarget,
        abi.encodeWithSelector(IAggregationExecutor.callBytes.selector, execution.targetData),
        desc,
        _isETH(desc.srcToken) ? msg.value : 0,
        address(this)
      );
      {
        // then take fee on dst token
        uint256 leftAmount = _takeFee(
          desc.dstToken,
          address(this),
          desc.feeReceivers,
          desc.feeAmounts,
          returnAmount,
          feeInBps
        );
        _doTransferERC20(desc.dstToken, address(this), dstReceiver, leftAmount);
      }
      returnAmount = _getBalance(desc.dstToken, dstReceiver) - initialDstReceiverBalance;
    }
    _checkReturnAmount(spentAmount, returnAmount, desc);
    emit Swapped(msg.sender, desc.srcToken, desc.dstToken, dstReceiver, spentAmount, returnAmount);
    emit Exchange(execution.callTarget, returnAmount, _isETH(desc.dstToken) ? WETH : address(desc.dstToken));
    emit ClientData(execution.clientData);
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function swapSimpleMode(
    IAggregationExecutor caller,
    SwapDescriptionV2 memory desc,
    bytes calldata executorData,
    bytes calldata clientData
  ) public returns (uint256 returnAmount, uint256 gasUsed) {
    uint256 gasBefore = gasleft();
    require(!_isETH(desc.srcToken), 'src is eth, should use normal swap');
    _permit(desc.srcToken, desc.amount, desc.permit);
    address dstReceiver = (desc.dstReceiver == address(0)) ? msg.sender : desc.dstReceiver;
    {
      bool isBps = _flagsChecked(desc.flags, _FEE_IN_BPS);
      if (!_flagsChecked(desc.flags, _FEE_ON_DST)) {
        // take fee and deduct total swap amount
        desc.amount = _takeFee(desc.srcToken, msg.sender, desc.feeReceivers, desc.feeAmounts, desc.amount, isBps);
      } else {
        dstReceiver = address(this);
      }
    }
    uint256 initialDstBalance = _getBalance(desc.dstToken, dstReceiver);
    uint256 initialSrcBalance = _getBalance(desc.srcToken, msg.sender);
    _swapMultiSequencesWithSimpleMode(
      caller,
      address(desc.srcToken),
      desc.amount,
      address(desc.dstToken),
      dstReceiver,
      executorData
    );
    // amount returned to this router
    returnAmount = _getBalance(desc.dstToken, dstReceiver) - initialDstBalance;
    {
      // take fee
      if (_flagsChecked(desc.flags, _FEE_ON_DST)) {
        {
          bool isBps = _flagsChecked(desc.flags, _FEE_IN_BPS);
          returnAmount = _takeFee(
            desc.dstToken,
            address(this),
            desc.feeReceivers,
            desc.feeAmounts,
            returnAmount,
            isBps
          );
        }
        IERC20 dstToken = desc.dstToken;
        dstReceiver = desc.dstReceiver == address(0) ? msg.sender : desc.dstReceiver;
        // dst receiver initial balance
        initialDstBalance = _getBalance(dstToken, dstReceiver);
        // transfer remainning token to dst receiver
        _doTransferERC20(dstToken, address(this), dstReceiver, returnAmount);
        // amount returned to dst receiver
        returnAmount = _getBalance(dstToken, dstReceiver) - initialDstBalance;
      }
    }
    uint256 spentAmount = initialSrcBalance - _getBalance(desc.srcToken, msg.sender);
    _checkReturnAmount(spentAmount, returnAmount, desc);
    emit Swapped(msg.sender, desc.srcToken, desc.dstToken, dstReceiver, spentAmount, returnAmount);
    emit Exchange(address(caller), returnAmount, _isETH(desc.dstToken) ? WETH : address(desc.dstToken));
    emit ClientData(clientData);
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function _doTransferERC20(
    IERC20 token,
    address from,
    address to,
    uint256 amount
  ) internal {
    require(from != to, 'sender != recipient');
    if (amount > 0) {
      if (_isETH(token)) {
        if (from == address(this)) TransferHelper.safeTransferETH(to, amount);
      } else {
        if (from == address(this)) {
          TransferHelper.safeTransfer(address(token), to, amount);
        } else {
          TransferHelper.safeTransferFrom(address(token), from, to, amount);
        }
      }
    }
  }
  // Only use this mode if the first pool of each sequence can receive tokenIn directly into the pool
  function _swapMultiSequencesWithSimpleMode(
    IAggregationExecutor caller,
    address tokenIn,
    uint256 totalSwapAmount,
    address tokenOut,
    address dstReceiver,
    bytes calldata data
  ) internal {
    SimpleSwapData memory swapData = abi.decode(data, (SimpleSwapData));
    require(swapData.deadline >= block.timestamp, 'ROUTER: Expired');
    require(
      swapData.firstPools.length == swapData.firstSwapAmounts.length &&
        swapData.firstPools.length == swapData.swapDatas.length,
      'invalid swap data length'
    );
    uint256 numberSeq = swapData.firstPools.length;
    for (uint256 i = 0; i < numberSeq; i++) {
      // collect amount to the first pool
      {
        uint256 balanceBefore = _getBalance(IERC20(tokenIn), msg.sender);
        _doTransferERC20(IERC20(tokenIn), msg.sender, swapData.firstPools[i], swapData.firstSwapAmounts[i]);
        require(swapData.firstSwapAmounts[i] <= totalSwapAmount, 'invalid swap amount');
        uint256 spentAmount = balanceBefore - _getBalance(IERC20(tokenIn), msg.sender);
        totalSwapAmount -= spentAmount;
      }
      {
        // solhint-disable-next-line avoid-low-level-calls
        // may take some native tokens for commission fee
        (bool success, bytes memory result) = address(caller).call(
          abi.encodeWithSelector(caller.swapSingleSequence.selector, swapData.swapDatas[i])
        );
        if (!success) {
          revert(RevertReasonParser.parse(result, 'swapSingleSequence failed: '));
        }
      }
    }
    {
      // solhint-disable-next-line avoid-low-level-calls
      // may take some native tokens for commission fee
      (bool success, bytes memory result) = address(caller).call(
        abi.encodeWithSelector(
          caller.finalTransactionProcessing.selector,
          tokenIn,
          tokenOut,
          dstReceiver,
          swapData.destTokenFeeData
        )
      );
      if (!success) {
        revert(RevertReasonParser.parse(result, 'finalTransactionProcessing failed: '));
      }
    }
  }
  function _getBalance(IERC20 token, address account) internal view returns (uint256) {
    if (_isETH(token)) {
      return account.balance;
    } else {
      return token.balanceOf(account);
    }
  }
  function _isETH(IERC20 token) internal pure returns (bool) {
    return (address(token) == ETH_ADDRESS);
  }
  /// @dev this function calls to external contract to execute swap and also validate the returned amounts
  function _executeSwap(
    address callTarget,
    bytes memory targetData,
    SwapDescriptionV2 memory desc,
    uint256 value,
    address dstReceiver
  ) internal returns (uint256 spentAmount, uint256 returnAmount) {
    uint256 initialDstBalance = _getBalance(desc.dstToken, dstReceiver);
    uint256 routerInitialSrcBalance = _getBalance(desc.srcToken, address(this));
    uint256 routerInitialDstBalance = _getBalance(desc.dstToken, address(this));
    {
      // call to external contract
      (bool success, ) = callTarget.call{value: value}(targetData);
      require(success, 'Call failed');
    }
    // if the `callTarget` returns amount to `msg.sender`, meaning this contract
    if (dstReceiver != address(this)) {
      uint256 stuckAmount = _getBalance(desc.dstToken, address(this)) - routerInitialDstBalance;
      _doTransferERC20(desc.dstToken, address(this), dstReceiver, stuckAmount);
    }
    // safe check here
    returnAmount = _getBalance(desc.dstToken, dstReceiver) - initialDstBalance;
    spentAmount = desc.amount;
    //should refund tokens router collected when partial fill
    if (
      _flagsChecked(desc.flags, _PARTIAL_FILL) && (_isETH(desc.srcToken) || _flagsChecked(desc.flags, _SHOULD_CLAIM))
    ) {
      uint256 currBalance = _getBalance(desc.srcToken, address(this));
      if (currBalance != routerInitialSrcBalance) {
        spentAmount = routerInitialSrcBalance - currBalance;
        _doTransferERC20(desc.srcToken, address(this), msg.sender, desc.amount - spentAmount);
      }
    }
  }
  function _collectExtraETHIfNeeded(SwapDescriptionV2 memory desc) internal {
    bool srcETH = _isETH(desc.srcToken);
    if (_flagsChecked(desc.flags, _REQUIRES_EXTRA_ETH)) {
      require(msg.value > (srcETH ? desc.amount : 0), 'Invalid msg.value');
    } else {
      require(msg.value == (srcETH ? desc.amount : 0), 'Invalid msg.value');
    }
  }
  function _collectTokenIfNeeded(
    SwapDescriptionV2 memory desc,
    address from,
    address to
  ) internal returns (bool collected, uint256 amount) {
    require(!_isETH(desc.srcToken), 'Claim token is ETH');
    uint256 initialRouterSrcBalance = _getBalance(desc.srcToken, address(this));
    _doTransferERC20(desc.srcToken, from, to, desc.amount);
    collected = true;
    amount = _getBalance(desc.srcToken, address(this)) - initialRouterSrcBalance;
  }
  /// @dev transfer fund to `callTarget` or approve `approveTarget`
  function _transferFromOrApproveTarget(
    address from,
    address approveTarget,
    SwapDescriptionV2 memory desc,
    bool collected
  ) internal {
    // if token is collected
    require(desc.srcReceivers.length == desc.srcAmounts.length, 'invalid srcReceivers length');
    if (collected) {
      if (_flagsChecked(desc.flags, _APPROVE_FUND) && approveTarget != address(0)) {
        // approve to approveTarget since some systems use an allowance proxy contract
        desc.srcToken.safeIncreaseAllowance(approveTarget, desc.amount);
        return;
      }
    }
    uint256 total;
    for (uint256 i; i < desc.srcReceivers.length; ++i) {
      total += desc.srcAmounts[i];
      _doTransferERC20(desc.srcToken, collected ? address(this) : from, desc.srcReceivers[i], desc.srcAmounts[i]);
    }
    require(total <= desc.amount, 'Exceeded desc.amount');
  }
  /// @dev token transferred from `from` to `feeData.recipients`
  function _takeFee(
    IERC20 token,
    address from,
    address[] memory recipients,
    uint256[] memory amounts,
    uint256 totalAmount,
    bool inBps
  ) internal returns (uint256 leftAmount) {
    leftAmount = totalAmount;
    uint256 recipientsLen = recipients.length;
    if (recipientsLen > 0) {
      bool isETH = _isETH(token);
      uint256 balanceBefore = _getBalance(token, isETH ? address(this) : from);
      require(amounts.length == recipientsLen, 'Invalid length');
      for (uint256 i; i < recipientsLen; ++i) {
        uint256 amount = inBps ? (totalAmount * amounts[i]) / BPS : amounts[i];
        _doTransferERC20(token, isETH ? address(this) : from, recipients[i], amount);
      }
      uint256 totalFee = balanceBefore - _getBalance(token, isETH ? address(this) : from);
      leftAmount = totalAmount - totalFee;
      emit Fee(address(token), totalAmount, totalFee, recipients, amounts, inBps);
    }
  }
  function _checkReturnAmount(
    uint256 spentAmount,
    uint256 returnAmount,
    SwapDescriptionV2 memory desc
  ) internal pure {
    if (_flagsChecked(desc.flags, _PARTIAL_FILL)) {
      require(returnAmount * desc.amount >= desc.minReturnAmount * spentAmount, 'Return amount is not enough');
    } else {
      require(returnAmount >= desc.minReturnAmount, 'Return amount is not enough');
    }
  }
  function _flagsChecked(uint256 number, uint256 flag) internal pure returns (bool) {
    return number & flag != 0;
  }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol';
import '../libraries/RevertReasonParser.sol';
/*
“Copyright (c) 2019-2021 1inch 
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions: 
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software. 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE”.
*/
contract Permitable {
  event Error(string reason);
  function _permit(
    IERC20 token,
    uint256 amount,
    bytes memory permit
  ) internal {
    if (permit.length == 32 * 7) {
      // solhint-disable-next-line avoid-low-level-calls
      (bool success, bytes memory result) = address(token).call(
        abi.encodePacked(IERC20Permit.permit.selector, permit)
      );
      if (!success) {
        string memory reason = RevertReasonParser.parse(result, 'Permit call failed: ');
        if (token.allowance(msg.sender, address(this)) < amount) {
          revert(reason);
        } else {
          emit Error(reason);
        }
      }
    }
  }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.12;
interface IAggregationExecutor {
  function callBytes(bytes calldata data) external payable; // 0xd9c45357
  // callbytes per swap sequence
  function swapSingleSequence(bytes calldata data) external;
  function finalTransactionProcessing(
    address tokenIn,
    address tokenOut,
    address to,
    bytes calldata destTokenFeeData
  ) external;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;
import '@openzeppelin/contracts/interfaces/IERC20.sol';
interface IAggregationExecutor1Inch {
  function callBytes(address msgSender, bytes calldata data) external payable; // 0x2636f7f8
}
interface IAggregationRouter1InchV4 {
  function swap(
    IAggregationExecutor1Inch caller,
    SwapDescription1Inch calldata desc,
    bytes calldata data
  ) external payable returns (uint256 returnAmount, uint256 gasLeft);
}
struct SwapDescription1Inch {
  IERC20 srcToken;
  IERC20 dstToken;
  address payable srcReceiver;
  address payable dstReceiver;
  uint256 amount;
  uint256 minReturnAmount;
  uint256 flags;
  bytes permit;
}
struct SwapDescriptionExecutor1Inch {
  IERC20 srcToken;
  IERC20 dstToken;
  address payable srcReceiver1Inch;
  address payable dstReceiver;
  address[] srcReceivers;
  uint256[] srcAmounts;
  uint256 amount;
  uint256 minReturnAmount;
  uint256 flags;
  bytes permit;
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.7.6;
/*
“Copyright (c) 2019-2021 1inch 
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions: 
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software. 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE”.
*/
library RevertReasonParser {
  function parse(bytes memory data, string memory prefix) internal pure returns (string memory) {
    // https://solidity.readthedocs.io/en/latest/control-structures.html#revert
    // We assume that revert reason is abi-encoded as Error(string)
    // 68 = 4-byte selector 0x08c379a0 + 32 bytes offset + 32 bytes length
    if (data.length >= 68 && data[0] == '\\x08' && data[1] == '\\xc3' && data[2] == '\\x79' && data[3] == '\\xa0') {
      string memory reason;
      // solhint-disable no-inline-assembly
      assembly {
        // 68 = 32 bytes data length + 4-byte selector + 32 bytes offset
        reason := add(data, 68)
      }
      /*
                revert reason is padded up to 32 bytes with ABI encoder: Error(string)
                also sometimes there is extra 32 bytes of zeros padded in the end:
                https://github.com/ethereum/solidity/issues/10170
                because of that we can't check for equality and instead check
                that string length + extra 68 bytes is less than overall data length
            */
      require(data.length >= 68 + bytes(reason).length, 'Invalid revert reason');
      return string(abi.encodePacked(prefix, 'Error(', reason, ')'));
    }
    // 36 = 4-byte selector 0x4e487b71 + 32 bytes integer
    else if (data.length == 36 && data[0] == '\\x4e' && data[1] == '\\x48' && data[2] == '\\x7b' && data[3] == '\\x71') {
      uint256 code;
      // solhint-disable no-inline-assembly
      assembly {
        // 36 = 32 bytes data length + 4-byte selector
        code := mload(add(data, 36))
      }
      return string(abi.encodePacked(prefix, 'Panic(', _toHex(code), ')'));
    }
    return string(abi.encodePacked(prefix, 'Unknown(', _toHex(data), ')'));
  }
  function _toHex(uint256 value) private pure returns (string memory) {
    return _toHex(abi.encodePacked(value));
  }
  function _toHex(bytes memory data) private pure returns (string memory) {
    bytes16 alphabet = 0x30313233343536373839616263646566;
    bytes memory str = new bytes(2 + data.length * 2);
    str[0] = '0';
    str[1] = 'x';
    for (uint256 i = 0; i < data.length; i++) {
      str[2 * i + 2] = alphabet[uint8(data[i] >> 4)];
      str[2 * i + 3] = alphabet[uint8(data[i] & 0x0f)];
    }
    return string(str);
  }
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.5.16;
// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
  function safeApprove(
    address token,
    address to,
    uint256 value
  ) internal {
    // bytes4(keccak256(bytes('approve(address,uint256)')));
    (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
    require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
  }
  function safeTransfer(
    address token,
    address to,
    uint256 value
  ) internal {
    // bytes4(keccak256(bytes('transfer(address,uint256)')));
    if (value == 0) return;
    (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
    require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FAILED');
  }
  function safeTransferFrom(
    address token,
    address from,
    address to,
    uint256 value
  ) internal {
    // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
    if (value == 0) return;
    (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
    require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FROM_FAILED');
  }
  function safeTransferETH(address to, uint256 value) internal {
    if (value == 0) return;
    (bool success, ) = to.call{value: value}(new bytes(0));
    require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
  }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC20.sol)
pragma solidity ^0.8.0;
import "../token/ERC20/IERC20.sol";
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);
    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../utils/Address.sol";
/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;
    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.
        return account.code.length > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (proxy/utils/Initializable.sol)
pragma solidity ^0.8.2;
import "../../utils/AddressUpgradeable.sol";
/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
 * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
 * case an upgrade adds a module that needs to be initialized.
 *
 * For example:
 *
 * [.hljs-theme-light.nopadding]
 * ```solidity
 * contract MyToken is ERC20Upgradeable {
 *     function initialize() initializer public {
 *         __ERC20_init("MyToken", "MTK");
 *     }
 * }
 *
 * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
 *     function initializeV2() reinitializer(2) public {
 *         __ERC20Permit_init("MyToken");
 *     }
 * }
 * ```
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
 * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() {
 *     _disableInitializers();
 * }
 * ```
 * ====
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     * @custom:oz-retyped-from bool
     */
    uint8 private _initialized;
    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;
    /**
     * @dev Triggered when the contract has been initialized or reinitialized.
     */
    event Initialized(uint8 version);
    /**
     * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
     * `onlyInitializing` functions can be used to initialize parent contracts.
     *
     * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
     * constructor.
     *
     * Emits an {Initialized} event.
     */
    modifier initializer() {
        bool isTopLevelCall = !_initializing;
        require(
            (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
            "Initializable: contract is already initialized"
        );
        _initialized = 1;
        if (isTopLevelCall) {
            _initializing = true;
        }
        _;
        if (isTopLevelCall) {
            _initializing = false;
            emit Initialized(1);
        }
    }
    /**
     * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
     * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
     * used to initialize parent contracts.
     *
     * A reinitializer may be used after the original initialization step. This is essential to configure modules that
     * are added through upgrades and that require initialization.
     *
     * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
     * cannot be nested. If one is invoked in the context of another, execution will revert.
     *
     * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
     * a contract, executing them in the right order is up to the developer or operator.
     *
     * WARNING: setting the version to 255 will prevent any future reinitialization.
     *
     * Emits an {Initialized} event.
     */
    modifier reinitializer(uint8 version) {
        require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
        _initialized = version;
        _initializing = true;
        _;
        _initializing = false;
        emit Initialized(version);
    }
    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} and {reinitializer} modifiers, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }
    /**
     * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
     * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
     * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
     * through proxies.
     *
     * Emits an {Initialized} event the first time it is successfully executed.
     */
    function _disableInitializers() internal virtual {
        require(!_initializing, "Initializable: contract is initializing");
        if (_initialized != type(uint8).max) {
            _initialized = type(uint8).max;
            emit Initialized(type(uint8).max);
        }
    }
    /**
     * @dev Returns the highest version that has been initialized. See {reinitializer}.
     */
    function _getInitializedVersion() internal view returns (uint8) {
        return _initialized;
    }
    /**
     * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
     */
    function _isInitializing() internal view returns (bool) {
        return _initializing;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20Upgradeable.sol";
import "./extensions/IERC20MetadataUpgradeable.sol";
import "../../utils/ContextUpgradeable.sol";
import {Initializable} from "../../proxy/utils/Initializable.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable, IERC20MetadataUpgradeable {
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    function __ERC20_init(string memory name_, string memory symbol_) internal onlyInitializing {
        __ERC20_init_unchained(name_, symbol_);
    }
    function __ERC20_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
        _name = name_;
        _symbol = symbol_;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the default value returned by this function, unless
     * it's overridden.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }
        return true;
    }
    /**
     * @dev Moves `amount` of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(address from, address to, uint256 amount) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(from, to, amount);
        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }
        emit Transfer(from, to, amount);
        _afterTokenTransfer(from, to, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);
        _afterTokenTransfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }
        emit Transfer(account, address(0), amount);
        _afterTokenTransfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}
    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[45] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20Upgradeable {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20Upgradeable.sol";
/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20MetadataUpgradeable is IERC20Upgradeable {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);
    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);
    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.
        return account.code.length > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)
pragma solidity ^0.8.0;
import {Initializable} from "../proxy/utils/Initializable.sol";
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract ContextUpgradeable is Initializable {
    function __Context_init() internal onlyInitializing {
    }
    function __Context_init_unchained() internal onlyInitializing {
    }
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[50] private __gap;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.27;
/// @dev Error for 0x0 address inputs
error InvalidZeroInput();
/// @dev Error for already added items to a list
error AlreadyAdded();
/// @dev Error for not found items in a list
error NotFound();
/// @dev Error for hitting max TVL
error MaxTVLReached();
/// @dev Error for caller not having permissions
error NotRestakeManagerAdmin();
/// @dev Error for call not coming from deposit queue contract
error NotDepositQueue();
/// @dev Error for contract being paused
error ContractPaused();
/// @dev Error for exceeding max basis points (100%)
error OverMaxBasisPoints();
/// @dev Error for invalid token decimals for collateral tokens (must be 18)
error InvalidTokenDecimals(uint8 expected, uint8 actual);
/// @dev Error when withdraw is already completed
error WithdrawAlreadyCompleted();
/// @dev Error when a different address tries to complete withdraw
error NotOriginalWithdrawCaller(address expectedCaller);
/// @dev Error when caller does not have OD admin role
error NotOperatorDelegatorAdmin();
/// @dev Error when caller does not have Oracle Admin role
error NotOracleAdmin();
/// @dev Error when caller is not RestakeManager contract
error NotRestakeManager();
/// @dev Errror when caller does not have ETH Restake Admin role
error NotNativeEthRestakeAdmin();
/// @dev Error when delegation address was already set - cannot be set again
error DelegateAddressAlreadySet();
/// @dev Error when caller does not have ERC20 Rewards Admin role
error NotERC20RewardsAdmin();
/// @dev Error when sending ETH fails
error TransferFailed();
/// @dev Error when caller does not have ETH Minter Burner Admin role
error NotEzETHMinterBurner();
/// @dev Error when caller does not have Token Admin role
error NotTokenAdmin();
/// @dev Error when price oracle is not configured
error OracleNotFound();
/// @dev Error when price oracle data is stale
error OraclePriceExpired();
/// @dev Error when array lengths do not match
error MismatchedArrayLengths();
/// @dev Error when caller does not have Deposit Withdraw Pauser role
error NotDepositWithdrawPauser();
/// @dev Error when an individual token TVL is over the max
error MaxTokenTVLReached();
/// @dev Error when Oracle price is invalid
error InvalidOraclePrice();
/// @dev Error when calling an invalid function
error NotImplemented();
/// @dev Error when calculating token amounts is invalid
error InvalidTokenAmount();
/// @dev Error when timestamp is invalid - likely in the past
error InvalidTimestamp(uint256 timestamp);
/// @dev Error when trade does not meet minimum output amount
error InsufficientOutputAmount();
/// @dev Error when the token received over the bridge is not the one expected
error InvalidTokenReceived();
/// @dev Error when the origin address is not whitelisted
error InvalidOrigin();
/// @dev Error when the sender is not expected
error InvalidSender(address expectedSender, address actualSender);
/// @dev error when function returns 0 amount
error InvalidZeroOutput();
/// @dev error when xRenzoBridge does not have enough balance to pay for fee
error NotEnoughBalance(uint256 currentBalance, uint256 calculatedFees);
/// @dev error when source chain is not expected
error InvalidSourceChain(uint64 expectedCCIPChainSelector, uint64 actualCCIPChainSelector);
/// @dev Error when an unauthorized address tries to call the bridge function on the L2
error UnauthorizedBridgeSweeper();
/// @dev Error when caller does not have BRIDGE_ADMIN role
error NotBridgeAdmin();
/// @dev Error when caller does not have PRICE_FEED_SENDER role
error NotPriceFeedSender();
/// @dev Error for connext price Feed unauthorised call
error UnAuthorisedCall();
/// @dev Error for no price feed configured on L2
error PriceFeedNotAvailable();
/// @dev Error for invalid bridge fee share configuration
error InvalidBridgeFeeShare(uint256 bridgeFee);
/// @dev Error for invalid sweep batch size
error InvalidSweepBatchSize(uint256 batchSize);
/// @dev Error when caller does not have Withdraw Queue admin role
error NotWithdrawQueueAdmin();
/// @dev Error when caller try to withdraw more than Buffer
error NotEnoughWithdrawBuffer();
/// @dev Error when caller try to claim withdraw before cooldown period
error EarlyClaim();
/// @dev Error when caller try to withdraw for unsupported asset
error UnsupportedWithdrawAsset();
/// @dev Error when caller try to claim invalidWithdrawIndex
error InvalidWithdrawIndex();
/// @dev Error when TVL was expected to be 0
error InvalidTVL();
/// @dev Error when incorrect BeaconChainStrategy is set for LST in completeQueuedWithdrawal
error IncorrectStrategy();
/// @dev Error when adding new OperatorDelegator which is not delegated
error OperatoDelegatorNotDelegated();
/// @dev Error when emergency tracking already tracked withdrawal
error WithdrawalAlreadyTracked();
/// @dev Error when emergency tracking already completed withdrawal
error WithdrawalAlreadyCompleted();
/// @dev Error when caller does not have Emergency Withdraw Tracking Admin role
error NotEmergencyWithdrawTrackingAdmin();
/// @dev Error when strategy does not have specified underlying
error InvalidStrategy();
/// @dev Error when strategy already set and hold non zero token balance
error NonZeroUnderlyingStrategyExist();
/// @dev Error when caller tried to claim queued withdrawal when not filled
error QueuedWithdrawalNotFilled();
/// @dev Error when caller does not have EigenLayerRewardsAdmin role
error NotEigenLayerRewardsAdmin();
/// @dev Error when rewardsDestination is not configured while trying to claim
error RewardsDestinationNotConfigured();
/// @dev Error when WETHUnwrapper is not configured while trying to claim WETH restaking rewards
error WETHUnwrapperNotConfigured();
/// @dev Error when currentCheckpoint is not accounted by OperatorDelegator
error CheckpointAlreadyActive();
/// @dev Error when specified checkpoint is already recorded
error CheckpointAlreadyRecorded();
/// @dev Error when caller does not have Emergency Checkpoint Tracking admin role
error NotEmergencyCheckpointTrackingAdmin();
/// @dev Error when last completed checkpoint on EigenPod is not recorded in OperatorDelegator
error CheckpointNotRecorded();
/// @dev Error when non pauser tries to change pause state
error NotPauser();
/// @dev Error when user tried to withdraw asset more than available in protocol collateral
error NotEnoughCollateralValue();
/// @dev Error when admin tries to disable asset withdraw queue which is not enabled
error WithdrawQueueNotEnabled();
/// @dev Error when admin tries to enable erc20 withdraw queue for IS_NATIVE address
error IsNativeAddressNotAllowed();
/// @dev Error when admin tried to complete queued withdrawal with receiveAsShares
error OnlyReceiveAsTokenAllowed();
/// @dev Error when Withdrawal is not queued
error WithdrawalNotQueued();
/// @dev Error when admin tries to track Withdraw of different staker
error InvalidStakerAddress();
/// @dev Error when caller does not have Emergency track AVS ETH slashing admin role
error NotEmergencyTrackAVSEthSlashingAdmin();
/// @dev Error when below the limit
error BelowAllowedLimit();
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.27;
interface IRoleManager {
    /// @dev Determines if the specified address has permissions to manage RoleManager
    /// @param potentialAddress Address to check
    function isRoleManagerAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to mint or burn ezETH tokens
    /// @param potentialAddress Address to check
    function isEzETHMinterBurner(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to update config on the OperatorDelgator Contracts
    /// @param potentialAddress Address to check
    function isOperatorDelegatorAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to update config on the Oracle Contract config
    /// @param potentialAddress Address to check
    function isOracleAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to update config on the Restake Manager
    /// @param potentialAddress Address to check
    function isRestakeManagerAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to update config on the Token Contract
    /// @param potentialAddress Address to check
    function isTokenAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to trigger restaking of native ETH
    /// @param potentialAddress Address to check
    function isNativeEthRestakeAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to sweep and deposit ERC20 Rewards
    /// @param potentialAddress Address to check
    function isERC20RewardsAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to pause deposits and withdraws
    /// @param potentialAddress Address to check
    function isDepositWithdrawPauser(address potentialAddress) external view returns (bool);
    /// @dev Determines if the specified address has permission to set whitelisted origin in xRenzoBridge
    /// @param potentialAddress Address to check
    function isBridgeAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determined if the specified address has permission to send price feed of ezETH to L2
    /// @param potentialAddress Address to check
    function isPriceFeedSender(address potentialAddress) external view returns (bool);
    /// @dev Determine if the specified address haas permission to update Withdraw Queue params
    /// @param potentialAddress Address to check
    function isWithdrawQueueAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determine if the specified address has permission to track emergency pending queued withdrawals
    /// @param potentialAddress Address to check
    function isEmergencyWithdrawTrackingAdmin(
        address potentialAddress
    ) external view returns (bool);
    /// @dev Determine if the specified address has permission to process EigenLayer rewards
    /// @param potentialAddress Address to check
    function isEigenLayerRewardsAdmin(address potentialAddress) external view returns (bool);
    /// @dev Determin if the specified address has permission to track missed Checkpoints Exit Balance
    /// @param potentialAddress Address to check
    function isEmergencyCheckpointTrackingAdmin(
        address potentialAddress
    ) external view returns (bool);
    /// @dev Determin if the specified address has permission to track AVS ETH slashing amount
    /// @param potentialAddress Address to check
    function isEmergencyTrackAVSEthSlashingAdmin(
        address potentialAddress
    ) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.9;
import "@openzeppelin/contracts-upgradeable/token/ERC20/ERC20Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
import "./IEzEthToken.sol";
import "../Permissions/IRoleManager.sol";
import "./EzEthTokenStorage.sol";
import "../Errors/Errors.sol";
/// @dev This contract is the ezETH ERC20 token
/// Ownership of the collateral in the protocol is tracked by the ezETH token
contract EzEthToken is Initializable, ERC20Upgradeable, IEzEthToken, EzEthTokenStorageV1 {
    /// @dev Allows only a whitelisted address to mint or burn ezETH tokens
    modifier onlyMinterBurner() {
        if (!roleManager.isEzETHMinterBurner(msg.sender)) revert NotEzETHMinterBurner();
        _;
    }
    /// @dev Allows only a whitelisted address to pause or unpause the token
    modifier onlyTokenAdmin() {
        if (!roleManager.isTokenAdmin(msg.sender)) revert NotTokenAdmin();
        _;
    }
    /// @dev Prevents implementation contract from being initialized.
    /// @custom:oz-upgrades-unsafe-allow constructor
    constructor() {
        _disableInitializers();
    }
    /// @dev Initializes the contract with initial vars
    function initialize(IRoleManager _roleManager) public initializer {
        if (address(_roleManager) == address(0x0)) revert InvalidZeroInput();
        __ERC20_init("ezETH", "Renzo Restaked ETH");
        roleManager = _roleManager;
    }
    /// @dev Allows minter/burner to mint new ezETH tokens to an address
    function mint(address to, uint256 amount) external onlyMinterBurner {
        _mint(to, amount);
    }
    /// @dev Allows minter/burner to burn ezETH tokens from an address
    function burn(address from, uint256 amount) external onlyMinterBurner {
        _burn(from, amount);
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return "Renzo Restaked ETH";
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return "ezETH";
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.27;
import "../Permissions/IRoleManager.sol";
/// @title EzEthTokenStorage
/// @dev This contract will hold all local variables for the  Contract
/// When upgrading the protocol, inherit from this contract on the V2 version and change the
/// StorageManager to inherit from the later version.  This ensures there are no storage layout
/// corruptions when upgrading.
contract EzEthTokenStorageV1 {
    /// @dev reference to the RoleManager contract
    IRoleManager public roleManager;
    /// @dev flag to control whether transfers are paused
    /// Deprecated: Token contract may no longer be paused
    bool public _deprecated_paused;
}
/// On the next version of the protocol, if new variables are added, put them in the below
/// contract and use this as the inheritance chain.
/**
contract EzEthTokenStorageV2 is EzEthTokenStorageV1 {
  address newVariable;
}
 */
// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.9;
import "@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol";
interface IEzEthToken is IERC20Upgradeable {
    function mint(address to, uint256 amount) external;
    function burn(address from, uint256 amount) external;
}

// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity >=0.7.0 <0.9.0;
/**
 * @notice Simple interface to retrieve the version of a deployed contract.
 */
interface IVersion {
    /**
     * @dev Returns a JSON representation of the contract version containing name, version number and task ID.
     */
    function version() external view returns (string memory);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma experimental ABIEncoderV2;
import "../solidity-utils/openzeppelin/IERC20.sol";
import "../solidity-utils/helpers/IAuthentication.sol";
import "../solidity-utils/helpers/ISignaturesValidator.sol";
import "../solidity-utils/helpers/ITemporarilyPausable.sol";
import "../solidity-utils/misc/IWETH.sol";
import "./IAsset.sol";
import "./IAuthorizer.sol";
import "./IFlashLoanRecipient.sol";
import "./IProtocolFeesCollector.sol";
pragma solidity ^0.7.0;
/**
 * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
 * don't override one of these declarations.
 */
interface IVault is ISignaturesValidator, ITemporarilyPausable, IAuthentication {
    // Generalities about the Vault:
    //
    // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
    // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
    // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
    // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
    // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
    //
    // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
    // while execution control is transferred to a token contract during a swap) will result in a revert. View
    // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
    // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
    //
    // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.
    // Authorizer
    //
    // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
    // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
    // can perform a given action.
    /**
     * @dev Returns the Vault's Authorizer.
     */
    function getAuthorizer() external view returns (IAuthorizer);
    /**
     * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
     *
     * Emits an `AuthorizerChanged` event.
     */
    function setAuthorizer(IAuthorizer newAuthorizer) external;
    /**
     * @dev Emitted when a new authorizer is set by `setAuthorizer`.
     */
    event AuthorizerChanged(IAuthorizer indexed newAuthorizer);
    // Relayers
    //
    // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
    // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
    // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
    // this power, two things must occur:
    //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
    //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
    //    functions.
    //  - Each user must approve the relayer to act on their behalf.
    // This double protection means users cannot be tricked into approving malicious relayers (because they will not
    // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
    // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.
    /**
     * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
     */
    function hasApprovedRelayer(address user, address relayer) external view returns (bool);
    /**
     * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
     *
     * Emits a `RelayerApprovalChanged` event.
     */
    function setRelayerApproval(
        address sender,
        address relayer,
        bool approved
    ) external;
    /**
     * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
     */
    event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);
    // Internal Balance
    //
    // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
    // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
    // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
    // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
    //
    // Internal Balance management features batching, which means a single contract call can be used to perform multiple
    // operations of different kinds, with different senders and recipients, at once.
    /**
     * @dev Returns `user`'s Internal Balance for a set of tokens.
     */
    function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);
    /**
     * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
     * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
     * it lets integrators reuse a user's Vault allowance.
     *
     * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
     */
    function manageUserBalance(UserBalanceOp[] memory ops) external payable;
    /**
     * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
     without manual WETH wrapping or unwrapping.
     */
    struct UserBalanceOp {
        UserBalanceOpKind kind;
        IAsset asset;
        uint256 amount;
        address sender;
        address payable recipient;
    }
    // There are four possible operations in `manageUserBalance`:
    //
    // - DEPOSIT_INTERNAL
    // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
    // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
    //
    // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
    // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
    // relevant for relayers).
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - WITHDRAW_INTERNAL
    // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
    //
    // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
    // it to the recipient as ETH.
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - TRANSFER_INTERNAL
    // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
    //
    // Reverts if the ETH sentinel value is passed.
    //
    // Emits an `InternalBalanceChanged` event.
    //
    //
    // - TRANSFER_EXTERNAL
    // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
    // relayers, as it lets them reuse a user's Vault allowance.
    //
    // Reverts if the ETH sentinel value is passed.
    //
    // Emits an `ExternalBalanceTransfer` event.
    enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }
    /**
     * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
     * interacting with Pools using Internal Balance.
     *
     * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
     * address.
     */
    event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);
    /**
     * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
     */
    event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);
    // Pools
    //
    // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
    // functionality:
    //
    //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
    // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
    // which increase with the number of registered tokens.
    //
    //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
    // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
    // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
    // independent of the number of registered tokens.
    //
    //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
    // minimal swap info Pools, these are called via IMinimalSwapInfoPool.
    enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }
    /**
     * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
     * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
     * changed.
     *
     * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
     * depending on the chosen specialization setting. This contract is known as the Pool's contract.
     *
     * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
     * multiple Pools may share the same contract.
     *
     * Emits a `PoolRegistered` event.
     */
    function registerPool(PoolSpecialization specialization) external returns (bytes32);
    /**
     * @dev Emitted when a Pool is registered by calling `registerPool`.
     */
    event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);
    /**
     * @dev Returns a Pool's contract address and specialization setting.
     */
    function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);
    /**
     * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
     *
     * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
     * exit by receiving registered tokens, and can only swap registered tokens.
     *
     * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
     * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
     * ascending order.
     *
     * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
     * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
     * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
     * expected to be highly secured smart contracts with sound design principles, and the decision to register an
     * Asset Manager should not be made lightly.
     *
     * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
     * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
     * different Asset Manager.
     *
     * Emits a `TokensRegistered` event.
     */
    function registerTokens(
        bytes32 poolId,
        IERC20[] memory tokens,
        address[] memory assetManagers
    ) external;
    /**
     * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
     */
    event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);
    /**
     * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
     *
     * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
     * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
     * must be deregistered in the same `deregisterTokens` call.
     *
     * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
     *
     * Emits a `TokensDeregistered` event.
     */
    function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;
    /**
     * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
     */
    event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);
    /**
     * @dev Returns detailed information for a Pool's registered token.
     *
     * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
     * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
     * equals the sum of `cash` and `managed`.
     *
     * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
     * `managed` or `total` balance to be greater than 2^112 - 1.
     *
     * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
     * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
     * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
     * change for this purpose, and will update `lastChangeBlock`.
     *
     * `assetManager` is the Pool's token Asset Manager.
     */
    function getPoolTokenInfo(bytes32 poolId, IERC20 token)
        external
        view
        returns (
            uint256 cash,
            uint256 managed,
            uint256 lastChangeBlock,
            address assetManager
        );
    /**
     * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
     * the tokens' `balances` changed.
     *
     * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
     * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
     *
     * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
     * order as passed to `registerTokens`.
     *
     * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
     * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
     * instead.
     */
    function getPoolTokens(bytes32 poolId)
        external
        view
        returns (
            IERC20[] memory tokens,
            uint256[] memory balances,
            uint256 lastChangeBlock
        );
    /**
     * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
     * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
     * Pool shares.
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
     * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
     * these maximums.
     *
     * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
     * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
     * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
     * back to the caller (not the sender, which is important for relayers).
     *
     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
     * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
     * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
     * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
     *
     * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
     * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
     * withdrawn from Internal Balance: attempting to do so will trigger a revert.
     *
     * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
     * their own custom logic. This typically requires additional information from the user (such as the expected number
     * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
     * directly to the Pool's contract, as is `recipient`.
     *
     * Emits a `PoolBalanceChanged` event.
     */
    function joinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        JoinPoolRequest memory request
    ) external payable;
    struct JoinPoolRequest {
        IAsset[] assets;
        uint256[] maxAmountsIn;
        bytes userData;
        bool fromInternalBalance;
    }
    /**
     * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
     * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
     * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
     * `getPoolTokenInfo`).
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
     * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
     * it just enforces these minimums.
     *
     * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
     * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
     * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
     *
     * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
     * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
     * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
     * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
     *
     * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
     * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
     * do so will trigger a revert.
     *
     * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
     * `tokens` array. This array must match the Pool's registered tokens.
     *
     * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
     * their own custom logic. This typically requires additional information from the user (such as the expected number
     * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
     * passed directly to the Pool's contract.
     *
     * Emits a `PoolBalanceChanged` event.
     */
    function exitPool(
        bytes32 poolId,
        address sender,
        address payable recipient,
        ExitPoolRequest memory request
    ) external;
    struct ExitPoolRequest {
        IAsset[] assets;
        uint256[] minAmountsOut;
        bytes userData;
        bool toInternalBalance;
    }
    /**
     * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
     */
    event PoolBalanceChanged(
        bytes32 indexed poolId,
        address indexed liquidityProvider,
        IERC20[] tokens,
        int256[] deltas,
        uint256[] protocolFeeAmounts
    );
    enum PoolBalanceChangeKind { JOIN, EXIT }
    // Swaps
    //
    // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
    // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
    // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
    //
    // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
    // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
    // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
    // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
    // individual swaps.
    //
    // There are two swap kinds:
    //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
    // `onSwap` hook) the amount of tokens out (to send to the recipient).
    //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
    // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
    //
    // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
    // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
    // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
    // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
    // the final intended token.
    //
    // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
    // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
    // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
    // much less gas than they would otherwise.
    //
    // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
    // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
    // updating the Pool's internal accounting).
    //
    // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
    // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
    // minimum amount of tokens to receive (by passing a negative value) is specified.
    //
    // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
    // this point in time (e.g. if the transaction failed to be included in a block promptly).
    //
    // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
    // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
    // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
    // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
    //
    // Finally, Internal Balance can be used when either sending or receiving tokens.
    enum SwapKind { GIVEN_IN, GIVEN_OUT }
    /**
     * @dev Performs a swap with a single Pool.
     *
     * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
     * taken from the Pool, which must be greater than or equal to `limit`.
     *
     * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
     * sent to the Pool, which must be less than or equal to `limit`.
     *
     * Internal Balance usage and the recipient are determined by the `funds` struct.
     *
     * Emits a `Swap` event.
     */
    function swap(
        SingleSwap memory singleSwap,
        FundManagement memory funds,
        uint256 limit,
        uint256 deadline
    ) external payable returns (uint256);
    /**
     * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
     * the `kind` value.
     *
     * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
     * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
     *
     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
     * used to extend swap behavior.
     */
    struct SingleSwap {
        bytes32 poolId;
        SwapKind kind;
        IAsset assetIn;
        IAsset assetOut;
        uint256 amount;
        bytes userData;
    }
    /**
     * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
     * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
     *
     * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
     * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
     * the same index in the `assets` array.
     *
     * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
     * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
     * `amountOut` depending on the swap kind.
     *
     * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
     * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
     * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
     *
     * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
     * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
     * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
     * or unwrapped from WETH by the Vault.
     *
     * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
     * the minimum or maximum amount of each token the vault is allowed to transfer.
     *
     * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
     * equivalent `swap` call.
     *
     * Emits `Swap` events.
     */
    function batchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds,
        int256[] memory limits,
        uint256 deadline
    ) external payable returns (int256[] memory);
    /**
     * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
     * `assets` array passed to that function, and ETH assets are converted to WETH.
     *
     * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
     * from the previous swap, depending on the swap kind.
     *
     * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
     * used to extend swap behavior.
     */
    struct BatchSwapStep {
        bytes32 poolId;
        uint256 assetInIndex;
        uint256 assetOutIndex;
        uint256 amount;
        bytes userData;
    }
    /**
     * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
     */
    event Swap(
        bytes32 indexed poolId,
        IERC20 indexed tokenIn,
        IERC20 indexed tokenOut,
        uint256 amountIn,
        uint256 amountOut
    );
    /**
     * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
     * `recipient` account.
     *
     * If the caller is not `sender`, it must be an authorized relayer for them.
     *
     * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
     * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
     * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
     * `joinPool`.
     *
     * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
     * transferred. This matches the behavior of `exitPool`.
     *
     * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
     * revert.
     */
    struct FundManagement {
        address sender;
        bool fromInternalBalance;
        address payable recipient;
        bool toInternalBalance;
    }
    /**
     * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
     * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
     *
     * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
     * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
     * receives are the same that an equivalent `batchSwap` call would receive.
     *
     * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
     * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
     * approve them for the Vault, or even know a user's address.
     *
     * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
     * eth_call instead of eth_sendTransaction.
     */
    function queryBatchSwap(
        SwapKind kind,
        BatchSwapStep[] memory swaps,
        IAsset[] memory assets,
        FundManagement memory funds
    ) external returns (int256[] memory assetDeltas);
    // Flash Loans
    /**
     * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
     * and then reverting unless the tokens plus a proportional protocol fee have been returned.
     *
     * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
     * for each token contract. `tokens` must be sorted in ascending order.
     *
     * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
     * `receiveFlashLoan` call.
     *
     * Emits `FlashLoan` events.
     */
    function flashLoan(
        IFlashLoanRecipient recipient,
        IERC20[] memory tokens,
        uint256[] memory amounts,
        bytes memory userData
    ) external;
    /**
     * @dev Emitted for each individual flash loan performed by `flashLoan`.
     */
    event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);
    // Asset Management
    //
    // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
    // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
    // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
    // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
    // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
    // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
    //
    // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
    // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
    //
    // This concept is unrelated to the IAsset interface.
    /**
     * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
     *
     * Pool Balance management features batching, which means a single contract call can be used to perform multiple
     * operations of different kinds, with different Pools and tokens, at once.
     *
     * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
     */
    function managePoolBalance(PoolBalanceOp[] memory ops) external;
    struct PoolBalanceOp {
        PoolBalanceOpKind kind;
        bytes32 poolId;
        IERC20 token;
        uint256 amount;
    }
    /**
     * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
     *
     * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
     *
     * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
     * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
     */
    enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }
    /**
     * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
     */
    event PoolBalanceManaged(
        bytes32 indexed poolId,
        address indexed assetManager,
        IERC20 indexed token,
        int256 cashDelta,
        int256 managedDelta
    );
    // Protocol Fees
    //
    // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
    // permissioned accounts.
    //
    // There are two kinds of protocol fees:
    //
    //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
    //
    //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
    // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
    // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
    // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
    // exiting a Pool in debt without first paying their share.
    /**
     * @dev Returns the current protocol fee module.
     */
    function getProtocolFeesCollector() external view returns (IProtocolFeesCollector);
    /**
     * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
     * error in some part of the system.
     *
     * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
     *
     * While the contract is paused, the following features are disabled:
     * - depositing and transferring internal balance
     * - transferring external balance (using the Vault's allowance)
     * - swaps
     * - joining Pools
     * - Asset Manager interactions
     *
     * Internal Balance can still be withdrawn, and Pools exited.
     */
    function setPaused(bool paused) external;
    /**
     * @dev Returns the Vault's WETH instance.
     */
    function WETH() external view returns (IWETH);
    // solhint-disable-previous-line func-name-mixedcase
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "@balancer-labs/v2-interfaces/contracts/pool-stable/StablePoolUserData.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/standalone-utils/IProtocolFeePercentagesProvider.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IRateProvider.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IVersion.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/ERC20Helpers.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
import "@balancer-labs/v2-pool-utils/contracts/BaseGeneralPool.sol";
import "@balancer-labs/v2-pool-utils/contracts/rates/PriceRateCache.sol";
import "./ComposableStablePoolStorage.sol";
import "./ComposableStablePoolRates.sol";
import "./ComposableStablePoolStorage.sol";
import "./ComposableStablePoolRates.sol";
import "./ComposableStablePoolProtocolFees.sol";
import "./StablePoolAmplification.sol";
import "./StableMath.sol";
/**
 * @dev StablePool with preminted BPT and rate providers for each token, allowing for e.g. wrapped tokens with a known
 * price ratio, such as Compound's cTokens.
 *
 * BPT is preminted on Pool initialization and registered as one of the Pool's tokens, allowing for swaps to behave as
 * single-token joins or exits (by swapping a token for BPT). We also support regular joins and exits, which can mint
 * and burn BPT.
 *
 * Preminted BPT is deposited in the Vault as the initial balance of the Pool, and doesn't belong to any entity until
 * transferred out of the Pool. The Pool's arithmetic behaves as if it didn't exist, and the BPT total supply is not
 * a useful value: we rely on the 'virtual supply' (how much BPT is actually owned outside the Vault) instead.
 */
contract ComposableStablePool is
    IRateProvider,
    IVersion,
    BaseGeneralPool,
    StablePoolAmplification,
    ComposableStablePoolRates,
    ComposableStablePoolProtocolFees
{
    using FixedPoint for uint256;
    using PriceRateCache for bytes32;
    using StablePoolUserData for bytes;
    using BasePoolUserData for bytes;
    // The maximum imposed by the Vault, which stores balances in a packed format, is 2**(112) - 1.
    // We are preminting half of that value (rounded up).
    uint256 private constant _PREMINTED_TOKEN_BALANCE = 2**(111);
    string private _version;
    // The constructor arguments are received in a struct to work around stack-too-deep issues
    struct NewPoolParams {
        IVault vault;
        IProtocolFeePercentagesProvider protocolFeeProvider;
        string name;
        string symbol;
        IERC20[] tokens;
        IRateProvider[] rateProviders;
        uint256[] tokenRateCacheDurations;
        bool exemptFromYieldProtocolFeeFlag;
        uint256 amplificationParameter;
        uint256 swapFeePercentage;
        uint256 pauseWindowDuration;
        uint256 bufferPeriodDuration;
        address owner;
        string version;
    }
    constructor(NewPoolParams memory params)
        BasePool(
            params.vault,
            IVault.PoolSpecialization.GENERAL,
            params.name,
            params.symbol,
            _insertSorted(params.tokens, IERC20(this)),
            new address[](params.tokens.length + 1),
            params.swapFeePercentage,
            params.pauseWindowDuration,
            params.bufferPeriodDuration,
            params.owner
        )
        StablePoolAmplification(params.amplificationParameter)
        ComposableStablePoolStorage(_extractStorageParams(params))
        ComposableStablePoolRates(_extractRatesParams(params))
        ProtocolFeeCache(params.protocolFeeProvider, ProtocolFeeCache.DELEGATE_PROTOCOL_SWAP_FEES_SENTINEL)
    {
        _version = params.version;
    }
    // Translate parameters to avoid stack-too-deep issues in the constructor
    function _extractRatesParams(NewPoolParams memory params)
        private
        pure
        returns (ComposableStablePoolRates.RatesParams memory)
    {
        return
            ComposableStablePoolRates.RatesParams({
                tokens: params.tokens,
                rateProviders: params.rateProviders,
                tokenRateCacheDurations: params.tokenRateCacheDurations
            });
    }
    // Translate parameters to avoid stack-too-deep issues in the constructor
    function _extractStorageParams(NewPoolParams memory params)
        private
        view
        returns (ComposableStablePoolStorage.StorageParams memory)
    {
        return
            ComposableStablePoolStorage.StorageParams({
                registeredTokens: _insertSorted(params.tokens, IERC20(this)),
                tokenRateProviders: params.rateProviders,
                exemptFromYieldProtocolFeeFlag: params.exemptFromYieldProtocolFeeFlag
            });
    }
    function version() external view override returns (string memory) {
        return _version;
    }
    /**
     * @notice Return the minimum BPT balance, required to avoid minimum token balances.
     * @dev This amount is minted and immediately burned on pool initialization, so that the total supply
     * (and therefore post-exit token balances), can never be zero. This keeps the math well-behaved when
     * liquidity is low. (It also provides an easy way to check whether a pool has been initialized, to
     * ensure this is only done once.)
     */
    function getMinimumBpt() external pure returns (uint256) {
        return _getMinimumBpt();
    }
    // BasePool hook
    /**
     * @dev Override base pool hook invoked before any swap, join, or exit to ensure rates are updated before
     * the operation.
     */
    function _beforeSwapJoinExit() internal override {
        super._beforeSwapJoinExit();
        // Before the scaling factors are read, we must update the cached rates, as those will be used to compute the
        // scaling factors.
        // Note that this is not done in a recovery mode exit (since _beforeSwapjoinExit() is not called under those
        // conditions), but this is fine as recovery mode exits are unaffected by scaling factors anyway.
        _cacheTokenRatesIfNecessary();
    }
    // Swap Hooks
    /**
     * @dev Override this hook called by the base class `onSwap`, to check whether we are doing a regular swap,
     * or a swap involving BPT, which is equivalent to a single token join or exit. Since one of the Pool's
     * tokens is the preminted BPT, we need to handle swaps where BPT is involved separately.
     *
     * At this point, the balances are unscaled. The indices are coming from the Vault, so they are indices into
     * the array of registered tokens (including BPT).
     *
     * If this is a swap involving BPT, call `_swapWithBpt`, which computes the amountOut using the swapFeePercentage
     * and charges protocol fees, in the same manner as single token join/exits. Otherwise, perform the default
     * processing for a regular swap.
     */
    function _swapGivenIn(
        SwapRequest memory swapRequest,
        uint256[] memory registeredBalances,
        uint256 registeredIndexIn,
        uint256 registeredIndexOut,
        uint256[] memory scalingFactors
    ) internal virtual override returns (uint256) {
        return
            (swapRequest.tokenIn == IERC20(this) || swapRequest.tokenOut == IERC20(this))
                ? _swapWithBpt(swapRequest, registeredBalances, registeredIndexIn, registeredIndexOut, scalingFactors)
                : super._swapGivenIn(
                    swapRequest,
                    registeredBalances,
                    registeredIndexIn,
                    registeredIndexOut,
                    scalingFactors
                );
    }
    /**
     * @dev Override this hook called by the base class `onSwap`, to check whether we are doing a regular swap,
     * or a swap involving BPT, which is equivalent to a single token join or exit. Since one of the Pool's
     * tokens is the preminted BPT, we need to handle swaps where BPT is involved separately.
     *
     * At this point, the balances are unscaled. The indices and balances are coming from the Vault, so they
     * refer to the full set of registered tokens (including BPT).
     *
     * If this is a swap involving BPT, call `_swapWithBpt`, which computes the amountOut using the swapFeePercentage
     * and charges protocol fees, in the same manner as single token join/exits. Otherwise, perform the default
     * processing for a regular swap.
     */
    function _swapGivenOut(
        SwapRequest memory swapRequest,
        uint256[] memory registeredBalances,
        uint256 registeredIndexIn,
        uint256 registeredIndexOut,
        uint256[] memory scalingFactors
    ) internal virtual override returns (uint256) {
        return
            (swapRequest.tokenIn == IERC20(this) || swapRequest.tokenOut == IERC20(this))
                ? _swapWithBpt(swapRequest, registeredBalances, registeredIndexIn, registeredIndexOut, scalingFactors)
                : super._swapGivenOut(
                    swapRequest,
                    registeredBalances,
                    registeredIndexIn,
                    registeredIndexOut,
                    scalingFactors
                );
    }
    /**
     * @dev This is called from the base class `_swapGivenIn`, so at this point the amount has been adjusted
     * for swap fees, and balances have had scaling applied. This will only be called for regular (non-BPT) swaps,
     * so forward to `onRegularSwap`.
     */
    function _onSwapGivenIn(
        SwapRequest memory request,
        uint256[] memory registeredBalances,
        uint256 registeredIndexIn,
        uint256 registeredIndexOut
    ) internal virtual override returns (uint256) {
        return
            _onRegularSwap(
                true, // given in
                request.amount,
                registeredBalances,
                registeredIndexIn,
                registeredIndexOut
            );
    }
    /**
     * @dev This is called from the base class `_swapGivenOut`, so at this point the amount has been adjusted
     * for swap fees, and balances have had scaling applied. This will only be called for regular (non-BPT) swaps,
     * so forward to `onRegularSwap`.
     */
    function _onSwapGivenOut(
        SwapRequest memory request,
        uint256[] memory registeredBalances,
        uint256 registeredIndexIn,
        uint256 registeredIndexOut
    ) internal virtual override returns (uint256) {
        return
            _onRegularSwap(
                false, // given out
                request.amount,
                registeredBalances,
                registeredIndexIn,
                registeredIndexOut
            );
    }
    /**
     * @dev Perform a swap between non-BPT tokens. Scaling and fee adjustments have been performed upstream, so
     * all we need to do here is calculate the price quote, depending on the direction of the swap.
     */
    function _onRegularSwap(
        bool isGivenIn,
        uint256 amountGiven,
        uint256[] memory registeredBalances,
        uint256 registeredIndexIn,
        uint256 registeredIndexOut
    ) private view returns (uint256) {
        // Adjust indices and balances for BPT token
        uint256[] memory balances = _dropBptItem(registeredBalances);
        uint256 indexIn = _skipBptIndex(registeredIndexIn);
        uint256 indexOut = _skipBptIndex(registeredIndexOut);
        (uint256 currentAmp, ) = _getAmplificationParameter();
        uint256 invariant = StableMath._calculateInvariant(currentAmp, balances);
        if (isGivenIn) {
            return StableMath._calcOutGivenIn(currentAmp, balances, indexIn, indexOut, amountGiven, invariant);
        } else {
            return StableMath._calcInGivenOut(currentAmp, balances, indexIn, indexOut, amountGiven, invariant);
        }
    }
    /**
     * @dev Perform a swap involving the BPT token, equivalent to a single-token join or exit. As with the standard
     * joins and swaps, we first pay any protocol fees pending from swaps that occurred since the previous join or
     * exit, then perform the operation (joinSwap or exitSwap), and finally store the "post operation" invariant and
     * amp, which establishes the new basis for protocol fees.
     *
     * At this point, the scaling factors (including rates) have been computed by the base class, but not yet applied
     * to the balances.
     */
    function _swapWithBpt(
        SwapRequest memory swapRequest,
        uint256[] memory registeredBalances,
        uint256 registeredIndexIn,
        uint256 registeredIndexOut,
        uint256[] memory scalingFactors
    ) private returns (uint256) {
        bool isGivenIn = swapRequest.kind == IVault.SwapKind.GIVEN_IN;
        _upscaleArray(registeredBalances, scalingFactors);
        swapRequest.amount = _upscale(
            swapRequest.amount,
            scalingFactors[isGivenIn ? registeredIndexIn : registeredIndexOut]
        );
        (
            uint256 preJoinExitSupply,
            uint256[] memory balances,
            uint256 currentAmp,
            uint256 preJoinExitInvariant
        ) = _beforeJoinExit(registeredBalances);
        // These calls mutate `balances` so that it holds the post join-exit balances.
        (uint256 amountCalculated, uint256 postJoinExitSupply) = registeredIndexOut == getBptIndex()
            ? _doJoinSwap(
                isGivenIn,
                swapRequest.amount,
                balances,
                _skipBptIndex(registeredIndexIn),
                currentAmp,
                preJoinExitSupply,
                preJoinExitInvariant
            )
            : _doExitSwap(
                isGivenIn,
                swapRequest.amount,
                balances,
                _skipBptIndex(registeredIndexOut),
                currentAmp,
                preJoinExitSupply,
                preJoinExitInvariant
            );
        _updateInvariantAfterJoinExit(
            currentAmp,
            balances,
            preJoinExitInvariant,
            preJoinExitSupply,
            postJoinExitSupply
        );
        return
            isGivenIn
                ? _downscaleDown(amountCalculated, scalingFactors[registeredIndexOut]) // Amount out, round down
                : _downscaleUp(amountCalculated, scalingFactors[registeredIndexIn]); // Amount in, round up
    }
    /**
     * @dev This mutates `balances` so that they become the post-joinswap balances. The StableMath interfaces
     * are different depending on the swap direction, so we forward to the appropriate low-level join function.
     */
    function _doJoinSwap(
        bool isGivenIn,
        uint256 amount,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 currentAmp,
        uint256 actualSupply,
        uint256 preJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        return
            isGivenIn
                ? _joinSwapExactTokenInForBptOut(
                    amount,
                    balances,
                    indexIn,
                    currentAmp,
                    actualSupply,
                    preJoinExitInvariant
                )
                : _joinSwapExactBptOutForTokenIn(
                    amount,
                    balances,
                    indexIn,
                    currentAmp,
                    actualSupply,
                    preJoinExitInvariant
                );
    }
    /**
     * @dev Since this is a join, we know the tokenOut is BPT. Since it is GivenIn, we know the tokenIn amount,
     * and must calculate the BPT amount out.
     * We are moving preminted BPT out of the Vault, which increases the virtual supply.
     */
    function _joinSwapExactTokenInForBptOut(
        uint256 amountIn,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 currentAmp,
        uint256 actualSupply,
        uint256 preJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        // The StableMath function was created with joins in mind, so it expects a full amounts array. We create an
        // empty one and only set the amount for the token involved.
        uint256[] memory amountsIn = new uint256[](balances.length);
        amountsIn[indexIn] = amountIn;
        uint256 bptOut = StableMath._calcBptOutGivenExactTokensIn(
            currentAmp,
            balances,
            amountsIn,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        balances[indexIn] = balances[indexIn].add(amountIn);
        uint256 postJoinExitSupply = actualSupply.add(bptOut);
        return (bptOut, postJoinExitSupply);
    }
    /**
     * @dev Since this is a join, we know the tokenOut is BPT. Since it is GivenOut, we know the BPT amount,
     * and must calculate the token amount in.
     * We are moving preminted BPT out of the Vault, which increases the virtual supply.
     */
    function _joinSwapExactBptOutForTokenIn(
        uint256 bptOut,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 currentAmp,
        uint256 actualSupply,
        uint256 preJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        uint256 amountIn = StableMath._calcTokenInGivenExactBptOut(
            currentAmp,
            balances,
            indexIn,
            bptOut,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        balances[indexIn] = balances[indexIn].add(amountIn);
        uint256 postJoinExitSupply = actualSupply.add(bptOut);
        return (amountIn, postJoinExitSupply);
    }
    /**
     * @dev This mutates balances so that they become the post-exitswap balances. The StableMath interfaces are
     * different depending on the swap direction, so we forward to the appropriate low-level exit function.
     */
    function _doExitSwap(
        bool isGivenIn,
        uint256 amount,
        uint256[] memory balances,
        uint256 indexOut,
        uint256 currentAmp,
        uint256 actualSupply,
        uint256 preJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        return
            isGivenIn
                ? _exitSwapExactBptInForTokenOut(
                    amount,
                    balances,
                    indexOut,
                    currentAmp,
                    actualSupply,
                    preJoinExitInvariant
                )
                : _exitSwapExactTokenOutForBptIn(
                    amount,
                    balances,
                    indexOut,
                    currentAmp,
                    actualSupply,
                    preJoinExitInvariant
                );
    }
    /**
     * @dev Since this is an exit, we know the tokenIn is BPT. Since it is GivenIn, we know the BPT amount,
     * and must calculate the token amount out.
     * We are moving BPT out of circulation and into the Vault, which decreases the virtual supply.
     */
    function _exitSwapExactBptInForTokenOut(
        uint256 bptAmount,
        uint256[] memory balances,
        uint256 indexOut,
        uint256 currentAmp,
        uint256 actualSupply,
        uint256 preJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        uint256 amountOut = StableMath._calcTokenOutGivenExactBptIn(
            currentAmp,
            balances,
            indexOut,
            bptAmount,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        balances[indexOut] = balances[indexOut].sub(amountOut);
        uint256 postJoinExitSupply = actualSupply.sub(bptAmount);
        return (amountOut, postJoinExitSupply);
    }
    /**
     * @dev Since this is an exit, we know the tokenIn is BPT. Since it is GivenOut, we know the token amount out,
     * and must calculate the BPT amount in.
     * We are moving BPT out of circulation and into the Vault, which decreases the virtual supply.
     */
    function _exitSwapExactTokenOutForBptIn(
        uint256 amountOut,
        uint256[] memory balances,
        uint256 indexOut,
        uint256 currentAmp,
        uint256 actualSupply,
        uint256 preJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        // The StableMath function was created with exits in mind, so it expects a full amounts array. We create an
        // empty one and only set the amount for the token involved.
        uint256[] memory amountsOut = new uint256[](balances.length);
        amountsOut[indexOut] = amountOut;
        uint256 bptAmount = StableMath._calcBptInGivenExactTokensOut(
            currentAmp,
            balances,
            amountsOut,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        balances[indexOut] = balances[indexOut].sub(amountOut);
        uint256 postJoinExitSupply = actualSupply.sub(bptAmount);
        return (bptAmount, postJoinExitSupply);
    }
    // Join Hooks
    /**
     * Since this Pool has preminted BPT which is stored in the Vault, it cannot simply be minted at construction.
     *
     * We take advantage of the fact that StablePools have an initialization step where BPT is minted to the first
     * account joining them, and perform both actions at once. By minting the entire BPT supply for the initial joiner
     * and then pulling all tokens except those due the joiner, we arrive at the desired state of the Pool holding all
     * BPT except the joiner's.
     */
    function _onInitializePool(
        bytes32,
        address sender,
        address,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal override returns (uint256, uint256[] memory) {
        StablePoolUserData.JoinKind kind = userData.joinKind();
        _require(kind == StablePoolUserData.JoinKind.INIT, Errors.UNINITIALIZED);
        // AmountsIn usually does not include the BPT token; initialization is the one time it has to.
        uint256[] memory amountsInIncludingBpt = userData.initialAmountsIn();
        InputHelpers.ensureInputLengthMatch(amountsInIncludingBpt.length, scalingFactors.length);
        _upscaleArray(amountsInIncludingBpt, scalingFactors);
        (uint256 amp, ) = _getAmplificationParameter();
        uint256[] memory amountsIn = _dropBptItem(amountsInIncludingBpt);
        uint256 invariantAfterJoin = StableMath._calculateInvariant(amp, amountsIn);
        // Set the initial BPT to the value of the invariant
        uint256 bptAmountOut = invariantAfterJoin;
        // BasePool will mint bptAmountOut for the sender: we then also mint the remaining BPT to make up the total
        // supply, and have the Vault pull those tokens from the sender as part of the join.
        // We are only minting half of the maximum value - already an amount many orders of magnitude greater than any
        // conceivable real liquidity - to allow for minting new BPT as a result of regular joins.
        //
        // Note that the sender need not approve BPT for the Vault as the Vault already has infinite BPT allowance for
        // all accounts.
        uint256 initialBpt = _PREMINTED_TOKEN_BALANCE.sub(bptAmountOut);
        _mintPoolTokens(sender, initialBpt);
        amountsInIncludingBpt[getBptIndex()] = initialBpt;
        // Initialization is still a join, so we need to do post-join work.
        _updatePostJoinExit(amp, invariantAfterJoin);
        return (bptAmountOut, amountsInIncludingBpt);
    }
    /**
     * @dev Base pool hook called from `onJoinPool`. Forward to `onJoinExitPool` with `isJoin` set to true.
     */
    function _onJoinPool(
        bytes32,
        address,
        address,
        uint256[] memory registeredBalances,
        uint256,
        uint256,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal override returns (uint256, uint256[] memory) {
        return _onJoinExitPool(true, registeredBalances, scalingFactors, userData);
    }
    /**
     * @dev Base pool hook called from `onExitPool`. Forward to `onJoinExitPool` with `isJoin` set to false.
     * Note that recovery mode exits do not call `_onExitPool`.
     */
    function _onExitPool(
        bytes32,
        address,
        address,
        uint256[] memory registeredBalances,
        uint256,
        uint256,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal override returns (uint256, uint256[] memory) {
        return _onJoinExitPool(false, registeredBalances, scalingFactors, userData);
    }
    /**
     * @dev Pay protocol fees before the operation, and call `_updateInvariantAfterJoinExit` afterward, to establish
     * the new basis for protocol fees.
     */
    function _onJoinExitPool(
        bool isJoin,
        uint256[] memory registeredBalances,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal returns (uint256, uint256[] memory) {
        (
            uint256 preJoinExitSupply,
            uint256[] memory balances,
            uint256 currentAmp,
            uint256 preJoinExitInvariant
        ) = _beforeJoinExit(registeredBalances);
            function(uint256[] memory, uint256, uint256, uint256, uint256[] memory, bytes memory)
                internal
                view
                returns (uint256, uint256[] memory) _doJoinOrExit
         = (isJoin ? _doJoin : _doExit);
        (uint256 bptAmount, uint256[] memory amountsDelta) = _doJoinOrExit(
            balances,
            currentAmp,
            preJoinExitSupply,
            preJoinExitInvariant,
            scalingFactors,
            userData
        );
        // Unlike joinswaps, explicit joins do not mutate balances into the post join-exit balances so we must perform
        // this mutation here.
        function(uint256, uint256) internal pure returns (uint256) _addOrSub = isJoin ? FixedPoint.add : FixedPoint.sub;
        _mutateAmounts(balances, amountsDelta, _addOrSub);
        uint256 postJoinExitSupply = _addOrSub(preJoinExitSupply, bptAmount);
        // Pass in the post-join balances to reset the protocol fee basis.
        // We are minting bptAmount, increasing the total (and virtual) supply post-join
        _updateInvariantAfterJoinExit(
            currentAmp,
            balances,
            preJoinExitInvariant,
            preJoinExitSupply,
            postJoinExitSupply
        );
        // For clarity and simplicity, arrays used and computed in lower level functions do not include BPT.
        // But the amountsIn array passed back to the Vault must include BPT, so we add it back in here.
        return (bptAmount, _addBptItem(amountsDelta, 0));
    }
    /**
     * @dev Pay any due protocol fees and calculate values necessary for performing the join/exit.
     */
    function _beforeJoinExit(uint256[] memory registeredBalances)
        internal
        returns (
            uint256,
            uint256[] memory,
            uint256,
            uint256
        )
    {
        (uint256 lastJoinExitAmp, uint256 lastPostJoinExitInvariant) = getLastJoinExitData();
        (
            uint256 preJoinExitSupply,
            uint256[] memory balances,
            uint256 oldAmpPreJoinExitInvariant
        ) = _payProtocolFeesBeforeJoinExit(registeredBalances, lastJoinExitAmp, lastPostJoinExitInvariant);
        // If the amplification factor is the same as it was during the last join/exit then we can reuse the
        // value calculated using the "old" amplification factor. If not, then we have to calculate this now.
        (uint256 currentAmp, ) = _getAmplificationParameter();
        uint256 preJoinExitInvariant = currentAmp == lastJoinExitAmp
            ? oldAmpPreJoinExitInvariant
            : StableMath._calculateInvariant(currentAmp, balances);
        return (preJoinExitSupply, balances, currentAmp, preJoinExitInvariant);
    }
    /**
     * @dev Support single- and multi-token joins, plus explicit proportional joins.
     */
    function _doJoin(
        uint256[] memory balances,
        uint256 currentAmp,
        uint256 preJoinExitSupply,
        uint256 preJoinExitInvariant,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal view returns (uint256, uint256[] memory) {
        StablePoolUserData.JoinKind kind = userData.joinKind();
        if (kind == StablePoolUserData.JoinKind.EXACT_TOKENS_IN_FOR_BPT_OUT) {
            return
                _joinExactTokensInForBPTOut(
                    preJoinExitSupply,
                    preJoinExitInvariant,
                    currentAmp,
                    balances,
                    scalingFactors,
                    userData
                );
        } else if (kind == StablePoolUserData.JoinKind.ALL_TOKENS_IN_FOR_EXACT_BPT_OUT) {
            return _joinAllTokensInForExactBptOut(preJoinExitSupply, balances, userData);
        } else if (kind == StablePoolUserData.JoinKind.TOKEN_IN_FOR_EXACT_BPT_OUT) {
            return _joinTokenInForExactBPTOut(preJoinExitSupply, preJoinExitInvariant, currentAmp, balances, userData);
        } else {
            _revert(Errors.UNHANDLED_JOIN_KIND);
        }
    }
    /**
     * @dev Proportional join. Pays no swap fees.
     */
    function _joinAllTokensInForExactBptOut(
        uint256 actualSupply,
        uint256[] memory balances,
        bytes memory userData
    ) private pure returns (uint256, uint256[] memory) {
        uint256 bptAmountOut = userData.allTokensInForExactBptOut();
        uint256[] memory amountsIn = StableMath._computeProportionalAmountsIn(balances, bptAmountOut, actualSupply);
        return (bptAmountOut, amountsIn);
    }
    /**
     * @dev Multi-token join. Joins with proportional amounts will pay no protocol fees.
     */
    function _joinExactTokensInForBPTOut(
        uint256 actualSupply,
        uint256 preJoinExitInvariant,
        uint256 currentAmp,
        uint256[] memory balances,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) private view returns (uint256, uint256[] memory) {
        (uint256[] memory amountsIn, uint256 minBPTAmountOut) = userData.exactTokensInForBptOut();
        InputHelpers.ensureInputLengthMatch(balances.length, amountsIn.length);
        // The user-provided amountsIn is unscaled, so we address that.
        _upscaleArray(amountsIn, _dropBptItem(scalingFactors));
        uint256 bptAmountOut = StableMath._calcBptOutGivenExactTokensIn(
            currentAmp,
            balances,
            amountsIn,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        _require(bptAmountOut >= minBPTAmountOut, Errors.BPT_OUT_MIN_AMOUNT);
        return (bptAmountOut, amountsIn);
    }
    /**
     * @dev Single-token join, equivalent to swapping a pool token for BPT.
     */
    function _joinTokenInForExactBPTOut(
        uint256 actualSupply,
        uint256 preJoinExitInvariant,
        uint256 currentAmp,
        uint256[] memory balances,
        bytes memory userData
    ) private view returns (uint256, uint256[] memory) {
        // Since this index is sent in from the user, we interpret it as NOT including the BPT token.
        (uint256 bptAmountOut, uint256 tokenIndex) = userData.tokenInForExactBptOut();
        // Note that there is no maximum amountIn parameter: this is handled by `IVault.joinPool`.
        // Balances are passed through from the Vault hook, and include BPT
        _require(tokenIndex < balances.length, Errors.OUT_OF_BOUNDS);
        // We join with a single token, so initialize amountsIn with zeros.
        uint256[] memory amountsIn = new uint256[](balances.length);
        // And then assign the result to the selected token.
        amountsIn[tokenIndex] = StableMath._calcTokenInGivenExactBptOut(
            currentAmp,
            balances,
            tokenIndex,
            bptAmountOut,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        return (bptAmountOut, amountsIn);
    }
    // Exit Hooks
    /**
     * @dev Support single- and multi-token exits, plus explicit proportional exits (in addition to the
     * recovery mode exit).
     */
    function _doExit(
        uint256[] memory balances,
        uint256 currentAmp,
        uint256 preJoinExitSupply,
        uint256 preJoinExitInvariant,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal view returns (uint256, uint256[] memory) {
        StablePoolUserData.ExitKind kind = userData.exitKind();
        if (kind == StablePoolUserData.ExitKind.BPT_IN_FOR_EXACT_TOKENS_OUT) {
            return
                _exitBPTInForExactTokensOut(
                    preJoinExitSupply,
                    preJoinExitInvariant,
                    currentAmp,
                    balances,
                    scalingFactors,
                    userData
                );
        } else if (kind == StablePoolUserData.ExitKind.EXACT_BPT_IN_FOR_ALL_TOKENS_OUT) {
            return _exitExactBPTInForTokensOut(preJoinExitSupply, balances, userData);
        } else if (kind == StablePoolUserData.ExitKind.EXACT_BPT_IN_FOR_ONE_TOKEN_OUT) {
            return _exitExactBPTInForTokenOut(preJoinExitSupply, preJoinExitInvariant, currentAmp, balances, userData);
        } else {
            _revert(Errors.UNHANDLED_EXIT_KIND);
        }
    }
    /**
     * @dev Proportional exit. Pays no swap fees. This is functionally equivalent to the recovery mode exit,
     * except this doesn't skip protocol fee collection, calling rate providers, etc., and doesn't require
     * recovery mode to be enabled.
     */
    function _exitExactBPTInForTokensOut(
        uint256 actualSupply,
        uint256[] memory balances,
        bytes memory userData
    ) private pure returns (uint256, uint256[] memory) {
        uint256 bptAmountIn = userData.exactBptInForTokensOut();
        uint256[] memory amountsOut = _computeProportionalAmountsOut(balances, actualSupply, bptAmountIn);
        return (bptAmountIn, amountsOut);
    }
    /**
     * @dev Multi-token exit. Proportional exits will pay no protocol fees.
     */
    function _exitBPTInForExactTokensOut(
        uint256 actualSupply,
        uint256 preJoinExitInvariant,
        uint256 currentAmp,
        uint256[] memory balances,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) private view returns (uint256, uint256[] memory) {
        (uint256[] memory amountsOut, uint256 maxBPTAmountIn) = userData.bptInForExactTokensOut();
        InputHelpers.ensureInputLengthMatch(amountsOut.length, balances.length);
        // The user-provided amountsIn is unscaled, so we address that.
        _upscaleArray(amountsOut, _dropBptItem(scalingFactors));
        uint256 bptAmountIn = StableMath._calcBptInGivenExactTokensOut(
            currentAmp,
            balances,
            amountsOut,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        _require(bptAmountIn <= maxBPTAmountIn, Errors.BPT_IN_MAX_AMOUNT);
        return (bptAmountIn, amountsOut);
    }
    /**
     * @dev Single-token exit, equivalent to swapping BPT for a pool token.
     */
    function _exitExactBPTInForTokenOut(
        uint256 actualSupply,
        uint256 preJoinExitInvariant,
        uint256 currentAmp,
        uint256[] memory balances,
        bytes memory userData
    ) private view returns (uint256, uint256[] memory) {
        // Since this index is sent in from the user, we interpret it as NOT including the BPT token
        (uint256 bptAmountIn, uint256 tokenIndex) = userData.exactBptInForTokenOut();
        // Note that there is no minimum amountOut parameter: this is handled by `IVault.exitPool`.
        _require(tokenIndex < balances.length, Errors.OUT_OF_BOUNDS);
        // We exit in a single token, so initialize amountsOut with zeros
        uint256[] memory amountsOut = new uint256[](balances.length);
        // And then assign the result to the selected token.
        amountsOut[tokenIndex] = StableMath._calcTokenOutGivenExactBptIn(
            currentAmp,
            balances,
            tokenIndex,
            bptAmountIn,
            actualSupply,
            preJoinExitInvariant,
            getSwapFeePercentage()
        );
        return (bptAmountIn, amountsOut);
    }
    /**
     * @dev We cannot use the default RecoveryMode implementation here, since we need to account for the BPT token.
     */
    function _doRecoveryModeExit(
        uint256[] memory registeredBalances,
        uint256,
        bytes memory userData
    ) internal virtual override returns (uint256, uint256[] memory) {
        // Since this Pool uses preminted BPT, we need to replace the total supply with the virtual total supply, and
        // adjust the balances array by removing BPT from it.
        // Note that we don't compute the actual supply, which would require a lot of complex calculations and
        // interactions with external components. This is fine because virtual and actual supply are the same while
        // recovery mode is enabled (since all protocol fees are forfeit and the fee percentages zeroed out).
        (uint256 virtualSupply, uint256[] memory balances) = _dropBptItemFromBalances(registeredBalances);
        (uint256 bptAmountIn, uint256[] memory amountsOut) = super._doRecoveryModeExit(
            balances,
            virtualSupply,
            userData
        );
        // The vault requires an array including BPT, so add it back in here.
        return (bptAmountIn, _addBptItem(amountsOut, 0));
    }
    // BPT rate
    /**
     * Many functions require accessing multiple internal values that might at first seem unrelated, but are actually
     * quite intertwined, and computed at the same time for optimal performance (since calculating some of them also
     * yields intermediate results useful for other queries). This helper function returns many of these values,
     * greatly reducing bytecode size.
     *
     * The return values are:
     *  @return balances - The current upscaled token balances (not including BPT)
     *  @return virtualSupply - The Pool's virtual supply
     *  @return protocolFeeAmount - The amount of unpaid protocol fees in BPT
     *  @return lastJoinExitAmp - The Pool's amplification factor at the last join or exit operation
     *  @return currentInvariantWithLastJoinExitAmp - The invariant of the current balances, calculated using the
     *  amplification factor at the last join or exit operation.
     */
    function _getSupplyAndFeesData()
        private
        view
        returns (
            uint256[] memory balances,
            uint256 virtualSupply,
            uint256 protocolFeeAmount,
            uint256 lastJoinExitAmp,
            uint256 currentInvariantWithLastJoinExitAmp
        )
    {
        // First we query the Vault for current registered balances (which includes preminted BPT), to then calculate
        // the current scaled balances and virtual supply.
        (, uint256[] memory registeredBalances, ) = getVault().getPoolTokens(getPoolId());
        _upscaleArray(registeredBalances, _scalingFactors());
        (virtualSupply, balances) = _dropBptItemFromBalances(registeredBalances);
        // Now we need to calculate any BPT due in the form of protocol fees. This requires data from the last join or
        // exit operation. `lastJoinExitAmp` can be useful in the scenario in which the amplification factor has not
        // changed, meaning this old value is equal to the current value.
        uint256 lastPostJoinExitInvariant;
        (lastJoinExitAmp, lastPostJoinExitInvariant) = getLastJoinExitData();
        // Computing the protocol ownership percentage also yields the invariant using the old amplification factor. If
        // it has not changed, then this is also the current invariant.
        uint256 expectedProtocolOwnershipPercentage;
        (
            expectedProtocolOwnershipPercentage,
            currentInvariantWithLastJoinExitAmp
        ) = _getProtocolPoolOwnershipPercentage(balances, lastJoinExitAmp, lastPostJoinExitInvariant);
        protocolFeeAmount = ProtocolFees.bptForPoolOwnershipPercentage(
            virtualSupply,
            expectedProtocolOwnershipPercentage
        );
    }
    /**
     * @dev This function returns the appreciation of BPT relative to the underlying tokens, as an 18 decimal fixed
     * point number. It is simply the ratio of the invariant to the BPT supply.
     *
     * The total supply is initialized to equal the invariant, so this value starts at one. During Pool operation the
     * invariant always grows and shrinks either proportionally to the total supply (in scenarios with no price impact,
     * e.g. proportional joins), or grows faster and shrinks more slowly than it (whenever swap fees are collected or
     * the token rates increase). Therefore, the rate is a monotonically increasing function.
     *
     * WARNING: since this function reads balances directly from the Vault, it is potentially subject to manipulation
     * via reentrancy if called within a Vault context (i.e. in the middle of a join or an exit). It is up to the
     * caller to ensure that the function is safe to call.
     *
     * This may happen e.g. if one of the tokens in the Pool contains some form of callback behavior in the
     * `transferFrom` function (like ERC777 tokens do). These tokens are strictly incompatible with the
     * Vault and Pool design, and are not safe to be used.
     *
     * There are also other situations where calling this function is unsafe. See
     * https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * To call this function safely, attempt to trigger the reentrancy guard in the Vault by calling a non-reentrant
     * function before calling `getRate`. That will make the transaction revert in an unsafe context.
     * (See `whenNotInVaultContext` in `ComposableStablePoolRates`).
     */
    function getRate() external view virtual override returns (uint256) {
        // We need to compute the current invariant and actual total supply. The latter includes protocol fees that have
        // accrued but are not yet minted: in calculating these we'll actually end up fetching most of the data we need
        // for the invariant.
        (
            uint256[] memory balances,
            uint256 virtualSupply,
            uint256 protocolFeeAmount,
            uint256 lastJoinExitAmp,
            uint256 currentInvariantWithLastJoinExitAmp
        ) = _getSupplyAndFeesData();
        // Due protocol fees will be minted at the next join or exit, so we can simply add them to the current virtual
        // supply to get the actual supply.
        uint256 actualTotalSupply = virtualSupply.add(protocolFeeAmount);
        // All that's missing now is the invariant. We have the balances required to calculate it already, but still
        // need the current amplification factor.
        (uint256 currentAmp, ) = _getAmplificationParameter();
        // It turns out that the process for due protocol fee calculation involves computing the current invariant,
        // except using the amplification factor at the last join or exit. This would typically not be terribly useful,
        // but since the amplification factor only changes rarely there is high probability of its current value being
        // the same as it was in the last join or exit. If that is the case, then we can skip the costly invariant
        // computation altogether.
        uint256 currentInvariant = (currentAmp == lastJoinExitAmp)
            ? currentInvariantWithLastJoinExitAmp
            : StableMath._calculateInvariant(currentAmp, balances);
        // With the current invariant and actual total supply, we can compute the rate as a fixed-point number.
        return currentInvariant.divDown(actualTotalSupply);
    }
    /**
     * @dev Returns the effective BPT supply.
     *
     * In other pools, this would be the same as `totalSupply`, but there are two key differences here:
     *  - this pool pre-mints BPT and holds it in the Vault as a token, and as such we need to subtract the Vault's
     *    balance to get the total "circulating supply". This is called the 'virtualSupply'.
     *  - the Pool owes debt to the Protocol in the form of unminted BPT, which will be minted immediately before the
     *    next join or exit. We need to take these into account since, even if they don't yet exist, they will
     *    effectively be included in any Pool operation that involves BPT.
     *
     * In the vast majority of cases, this function should be used instead of `totalSupply()`.
     *
     * **IMPORTANT NOTE**: calling this function within a Vault context (i.e. in the middle of a join or an exit) is
     * potentially unsafe, since the returned value is manipulable. It is up to the caller to ensure safety.
     *
     * This is because this function calculates the invariant, which requires the state of the pool to be in sync
     * with the state of the Vault. That condition may not be true in the middle of a join or an exit.
     *
     * To call this function safely, attempt to trigger the reentrancy guard in the Vault by calling a non-reentrant
     * function before calling `getActualSupply`. That will make the transaction revert in an unsafe context.
     * (See `whenNotInVaultContext` in `ComposableStablePoolRates`).
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    function getActualSupply() external view returns (uint256) {
        (, uint256 virtualSupply, uint256 protocolFeeAmount, , ) = _getSupplyAndFeesData();
        return virtualSupply.add(protocolFeeAmount);
    }
    /**
     * @dev This function will revert when called within a Vault context (i.e. in the middle of a join or an exit).
     *
     * This function depends on the invariant value, which may be calculated incorrectly in the middle of a join or
     * an exit, because the state of the pool could be out of sync with the state of the Vault. The modifier
     * `whenNotInVaultContext` prevents calling this function (and in turn, the external
     * `updateProtocolFeePercentageCache`) in such a context.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    function _beforeProtocolFeeCacheUpdate() internal override whenNotInVaultContext {
        // The `getRate()` function depends on the actual supply, which in turn depends on the cached protocol fee
        // percentages. Changing these would therefore result in the rate changing, which is not acceptable as this is a
        // sensitive value.
        // Because of this, we pay any due protocol fees *before* updating the cache, making it so that the new
        // percentages only affect future operation of the Pool, and not past fees. As a result, `getRate()` is
        // unaffected by the cached protocol fee percentages changing.
        // Given that this operation is state-changing and relatively complex, we only allow it as long as the Pool is
        // not paused.
        _ensureNotPaused();
        // We need to calculate the amount of unminted BPT that represents protocol fees to then pay those. This yields
        // some auxiliary values that turn out to also be useful for the rest of the tasks we want to perform.
        (
            uint256[] memory balances,
            ,
            uint256 protocolFeeAmount,
            uint256 lastJoinExitAmp,
            uint256 currentInvariantWithLastJoinExitAmp
        ) = _getSupplyAndFeesData();
        if (protocolFeeAmount > 0) {
            _payProtocolFees(protocolFeeAmount);
        }
        // With the fees paid, we now need to calculate the current invariant so we can store it alongside the current
        // amplification factor, marking the Pool as free of protocol debt.
        (uint256 currentAmp, ) = _getAmplificationParameter();
        // It turns out that the process for due protocol fee calculation involves computing the current invariant,
        // except using the amplification factor at the last join or exit. This would typically not be terribly useful,
        // but since the amplification factor only changes rarely there is high probability of its current value being
        // the same as it was in the last join or exit. If that is the case, then we can skip the costly invariant
        // computation altogether.
        uint256 currentInvariant = (currentAmp == lastJoinExitAmp)
            ? currentInvariantWithLastJoinExitAmp
            : StableMath._calculateInvariant(currentAmp, balances);
        _updatePostJoinExit(currentAmp, currentInvariant);
    }
    /**
     * @dev This function will revert when called within a Vault context (i.e. in the middle of a join or an exit).
     *
     * This function depends on the invariant value, which may be calculated incorrectly in the middle of a join or
     * an exit, because the state of the pool could be out of sync with the state of the Vault.
     *
     * The modifier `whenNotInVaultContext` prevents calling this function (and in turn, the external
     * `disableRecoveryMode`) in such a context.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    function _onDisableRecoveryMode() internal override whenNotInVaultContext {
        // Enabling recovery mode short-circuits protocol fee computations, forcefully returning a zero percentage,
        // increasing the return value of `getRate()` and effectively forfeiting due protocol fees.
        // Therefore, when exiting recovery mode we store the current invariant and the amplification factor used to
        // compute it, marking the Pool as free of protocol debt. Otherwise it'd be possible for debt to be
        // retroactively accrued, which would be incorrect and could lead to the value of `getRate` decreasing.
        (, uint256[] memory registeredBalances, ) = getVault().getPoolTokens(getPoolId());
        _upscaleArray(registeredBalances, _scalingFactors());
        uint256[] memory balances = _dropBptItem(registeredBalances);
        (uint256 currentAmp, ) = _getAmplificationParameter();
        uint256 currentInvariant = StableMath._calculateInvariant(currentAmp, balances);
        _updatePostJoinExit(currentAmp, currentInvariant);
    }
    // Helpers
    /**
     * @dev Mutates `amounts` by applying `mutation` with each entry in `arguments`.
     *
     * Equivalent to `amounts = amounts.map(mutation)`.
     */
    function _mutateAmounts(
        uint256[] memory toMutate,
        uint256[] memory arguments,
        function(uint256, uint256) pure returns (uint256) mutation
    ) private pure {
        uint256 length = toMutate.length;
        InputHelpers.ensureInputLengthMatch(length, arguments.length);
        for (uint256 i = 0; i < length; ++i) {
            toMutate[i] = mutation(toMutate[i], arguments[i]);
        }
    }
    // Permissioned functions
    /**
     * @dev Inheritance rules still require us to override this in the most derived contract, even though
     * it only calls super.
     */
    function _isOwnerOnlyAction(bytes32 actionId)
        internal
        view
        virtual
        override(
            // Our inheritance pattern creates a small diamond that requires explicitly listing the parents here.
            // Each parent calls the `super` version, so linearization ensures all implementations are called.
            BasePool,
            ComposableStablePoolProtocolFees,
            StablePoolAmplification,
            ComposableStablePoolRates
        )
        returns (bool)
    {
        return super._isOwnerOnlyAction(actionId);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
interface IAuthentication {
    /**
     * @dev Returns the action identifier associated with the external function described by `selector`.
     */
    function getActionId(bytes4 selector) external view returns (bytes32);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
 */
interface ISignaturesValidator {
    /**
     * @dev Returns the EIP712 domain separator.
     */
    function getDomainSeparator() external view returns (bytes32);
    /**
     * @dev Returns the next nonce used by an address to sign messages.
     */
    function getNextNonce(address user) external view returns (uint256);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev Interface for the TemporarilyPausable helper.
 */
interface ITemporarilyPausable {
    /**
     * @dev Emitted every time the pause state changes by `_setPaused`.
     */
    event PausedStateChanged(bool paused);
    /**
     * @dev Returns the current paused state.
     */
    function getPausedState()
        external
        view
        returns (
            bool paused,
            uint256 pauseWindowEndTime,
            uint256 bufferPeriodEndTime
        );
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../openzeppelin/IERC20.sol";
/**
 * @dev Interface for WETH9.
 * See https://github.com/gnosis/canonical-weth/blob/0dd1ea3e295eef916d0c6223ec63141137d22d67/contracts/WETH9.sol
 */
interface IWETH is IERC20 {
    function deposit() external payable;
    function withdraw(uint256 amount) external;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
 * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
 * types.
 *
 * This concept is unrelated to a Pool's Asset Managers.
 */
interface IAsset {
    // solhint-disable-previous-line no-empty-blocks
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
interface IAuthorizer {
    /**
     * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
     */
    function canPerform(
        bytes32 actionId,
        address account,
        address where
    ) external view returns (bool);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
// Inspired by Aave Protocol's IFlashLoanReceiver.
import "../solidity-utils/openzeppelin/IERC20.sol";
interface IFlashLoanRecipient {
    /**
     * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
     *
     * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
     * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
     * Vault, or else the entire flash loan will revert.
     *
     * `userData` is the same value passed in the `IVault.flashLoan` call.
     */
    function receiveFlashLoan(
        IERC20[] memory tokens,
        uint256[] memory amounts,
        uint256[] memory feeAmounts,
        bytes memory userData
    ) external;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../solidity-utils/openzeppelin/IERC20.sol";
import "./IVault.sol";
import "./IAuthorizer.sol";
interface IProtocolFeesCollector {
    event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
    event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);
    function withdrawCollectedFees(
        IERC20[] calldata tokens,
        uint256[] calldata amounts,
        address recipient
    ) external;
    function setSwapFeePercentage(uint256 newSwapFeePercentage) external;
    function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external;
    function getSwapFeePercentage() external view returns (uint256);
    function getFlashLoanFeePercentage() external view returns (uint256);
    function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts);
    function getAuthorizer() external view returns (IAuthorizer);
    function vault() external view returns (IVault);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
/**
 * @dev Source of truth for all Protocol Fee percentages, that is, how much the protocol charges certain actions. Some
 * of these values may also be retrievable from other places (such as the swap fee percentage), but this is the
 * preferred source nonetheless.
 */
interface IProtocolFeePercentagesProvider {
    // All fee percentages are 18-decimal fixed point numbers, so e.g. 1e18 = 100% and 1e16 = 1%.
    // Emitted when a new fee type is registered.
    event ProtocolFeeTypeRegistered(uint256 indexed feeType, string name, uint256 maximumPercentage);
    // Emitted when the value of a fee type changes.
    // IMPORTANT: it is possible for a third party to modify the SWAP and FLASH_LOAN fee type values directly in the
    // ProtocolFeesCollector, which will result in this event not being emitted despite their value changing. Such usage
    // of the ProtocolFeesCollector is however discouraged: all state-changing interactions with it should originate in
    // this contract.
    event ProtocolFeePercentageChanged(uint256 indexed feeType, uint256 percentage);
    /**
     * @dev Registers a new fee type in the system, making it queryable via `getFeeTypePercentage` and `getFeeTypeName`,
     * as well as configurable via `setFeeTypePercentage`.
     *
     * `feeType` can be any arbitrary value (that is not in use).
     *
     * It is not possible to de-register fee types, nor change their name or maximum value.
     */
    function registerFeeType(
        uint256 feeType,
        string memory name,
        uint256 maximumValue,
        uint256 initialValue
    ) external;
    /**
     * @dev Returns true if `feeType` has been registered and can be queried.
     */
    function isValidFeeType(uint256 feeType) external view returns (bool);
    /**
     * @dev Returns true if `value` is a valid percentage value for `feeType`.
     */
    function isValidFeeTypePercentage(uint256 feeType, uint256 value) external view returns (bool);
    /**
     * @dev Sets the percentage value for `feeType` to `newValue`.
     *
     * IMPORTANT: it is possible for a third party to modify the SWAP and FLASH_LOAN fee type values directly in the
     * ProtocolFeesCollector, without invoking this function. This will result in the `ProtocolFeePercentageChanged`
     * event not being emitted despite their value changing. Such usage of the ProtocolFeesCollector is however
     * discouraged: only this contract should be granted permission to call `setSwapFeePercentage` and
     * `setFlashLoanFeePercentage`.
     */
    function setFeeTypePercentage(uint256 feeType, uint256 newValue) external;
    /**
     * @dev Returns the current percentage value for `feeType`. This is the preferred mechanism for querying these -
     * whenever possible, use this fucntion instead of e.g. querying the ProtocolFeesCollector.
     */
    function getFeeTypePercentage(uint256 feeType) external view returns (uint256);
    /**
     * @dev Returns `feeType`'s maximum value.
     */
    function getFeeTypeMaximumPercentage(uint256 feeType) external view returns (uint256);
    /**
     * @dev Returns `feeType`'s name.
     */
    function getFeeTypeName(uint256 feeType) external view returns (string memory);
}
library ProtocolFeeType {
    // This list is not exhaustive - more fee types can be added to the system. It is expected for this list to be
    // extended with new fee types as they are registered, to keep them all in one place and reduce
    // likelihood of user error.
    // solhint-disable private-vars-leading-underscore
    uint256 internal constant SWAP = 0;
    uint256 internal constant FLASH_LOAN = 1;
    uint256 internal constant YIELD = 2;
    uint256 internal constant AUM = 3;
    // solhint-enable private-vars-leading-underscore
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
// solhint-disable
/**
 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
 * supported.
 * Uses the default 'BAL' prefix for the error code
 */
function _require(bool condition, uint256 errorCode) pure {
    if (!condition) _revert(errorCode);
}
/**
 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
 * supported.
 */
function _require(bool condition, uint256 errorCode, bytes3 prefix) pure {
    if (!condition) _revert(errorCode, prefix);
}
/**
 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
 * Uses the default 'BAL' prefix for the error code
 */
function _revert(uint256 errorCode) pure {
    _revert(errorCode, 0x42414c); // This is the raw byte representation of "BAL"
}
/**
 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
 */
function _revert(uint256 errorCode, bytes3 prefix) pure {
    uint256 prefixUint = uint256(uint24(prefix));
    // We're going to dynamically create a revert string based on the error code, with the following format:
    // 'BAL#{errorCode}'
    // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
    //
    // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
    // number (8 to 16 bits) than the individual string characters.
    //
    // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
    assembly {
        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
        // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
        // the '0' character.
        let units := add(mod(errorCode, 10), 0x30)
        errorCode := div(errorCode, 10)
        let tenths := add(mod(errorCode, 10), 0x30)
        errorCode := div(errorCode, 10)
        let hundreds := add(mod(errorCode, 10), 0x30)
        // With the individual characters, we can now construct the full string.
        // We first append the '#' character (0x23) to the prefix. In the case of 'BAL', it results in 0x42414c23 ('BAL#')
        // Then, we shift this by 24 (to provide space for the 3 bytes of the error code), and add the
        // characters to it, each shifted by a multiple of 8.
        // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
        // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
        // array).
        let formattedPrefix := shl(24, add(0x23, shl(8, prefixUint)))
        let revertReason := shl(200, add(formattedPrefix, add(add(units, shl(8, tenths)), shl(16, hundreds))))
        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
        // message will have the following layout:
        // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]
        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
        // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
        // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
        // The string length is fixed: 7 characters.
        mstore(0x24, 7)
        // Finally, the string itself is stored.
        mstore(0x44, revertReason)
        // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
        revert(0, 100)
    }
}
library Errors {
    // Math
    uint256 internal constant ADD_OVERFLOW = 0;
    uint256 internal constant SUB_OVERFLOW = 1;
    uint256 internal constant SUB_UNDERFLOW = 2;
    uint256 internal constant MUL_OVERFLOW = 3;
    uint256 internal constant ZERO_DIVISION = 4;
    uint256 internal constant DIV_INTERNAL = 5;
    uint256 internal constant X_OUT_OF_BOUNDS = 6;
    uint256 internal constant Y_OUT_OF_BOUNDS = 7;
    uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
    uint256 internal constant INVALID_EXPONENT = 9;
    // Input
    uint256 internal constant OUT_OF_BOUNDS = 100;
    uint256 internal constant UNSORTED_ARRAY = 101;
    uint256 internal constant UNSORTED_TOKENS = 102;
    uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
    uint256 internal constant ZERO_TOKEN = 104;
    // Shared pools
    uint256 internal constant MIN_TOKENS = 200;
    uint256 internal constant MAX_TOKENS = 201;
    uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
    uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
    uint256 internal constant MINIMUM_BPT = 204;
    uint256 internal constant CALLER_NOT_VAULT = 205;
    uint256 internal constant UNINITIALIZED = 206;
    uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
    uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
    uint256 internal constant EXPIRED_PERMIT = 209;
    uint256 internal constant NOT_TWO_TOKENS = 210;
    uint256 internal constant DISABLED = 211;
    // Pools
    uint256 internal constant MIN_AMP = 300;
    uint256 internal constant MAX_AMP = 301;
    uint256 internal constant MIN_WEIGHT = 302;
    uint256 internal constant MAX_STABLE_TOKENS = 303;
    uint256 internal constant MAX_IN_RATIO = 304;
    uint256 internal constant MAX_OUT_RATIO = 305;
    uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
    uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
    uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
    uint256 internal constant INVALID_TOKEN = 309;
    uint256 internal constant UNHANDLED_JOIN_KIND = 310;
    uint256 internal constant ZERO_INVARIANT = 311;
    uint256 internal constant ORACLE_INVALID_SECONDS_QUERY = 312;
    uint256 internal constant ORACLE_NOT_INITIALIZED = 313;
    uint256 internal constant ORACLE_QUERY_TOO_OLD = 314;
    uint256 internal constant ORACLE_INVALID_INDEX = 315;
    uint256 internal constant ORACLE_BAD_SECS = 316;
    uint256 internal constant AMP_END_TIME_TOO_CLOSE = 317;
    uint256 internal constant AMP_ONGOING_UPDATE = 318;
    uint256 internal constant AMP_RATE_TOO_HIGH = 319;
    uint256 internal constant AMP_NO_ONGOING_UPDATE = 320;
    uint256 internal constant STABLE_INVARIANT_DIDNT_CONVERGE = 321;
    uint256 internal constant STABLE_GET_BALANCE_DIDNT_CONVERGE = 322;
    uint256 internal constant RELAYER_NOT_CONTRACT = 323;
    uint256 internal constant BASE_POOL_RELAYER_NOT_CALLED = 324;
    uint256 internal constant REBALANCING_RELAYER_REENTERED = 325;
    uint256 internal constant GRADUAL_UPDATE_TIME_TRAVEL = 326;
    uint256 internal constant SWAPS_DISABLED = 327;
    uint256 internal constant CALLER_IS_NOT_LBP_OWNER = 328;
    uint256 internal constant PRICE_RATE_OVERFLOW = 329;
    uint256 internal constant INVALID_JOIN_EXIT_KIND_WHILE_SWAPS_DISABLED = 330;
    uint256 internal constant WEIGHT_CHANGE_TOO_FAST = 331;
    uint256 internal constant LOWER_GREATER_THAN_UPPER_TARGET = 332;
    uint256 internal constant UPPER_TARGET_TOO_HIGH = 333;
    uint256 internal constant UNHANDLED_BY_LINEAR_POOL = 334;
    uint256 internal constant OUT_OF_TARGET_RANGE = 335;
    uint256 internal constant UNHANDLED_EXIT_KIND = 336;
    uint256 internal constant UNAUTHORIZED_EXIT = 337;
    uint256 internal constant MAX_MANAGEMENT_SWAP_FEE_PERCENTAGE = 338;
    uint256 internal constant UNHANDLED_BY_MANAGED_POOL = 339;
    uint256 internal constant UNHANDLED_BY_PHANTOM_POOL = 340;
    uint256 internal constant TOKEN_DOES_NOT_HAVE_RATE_PROVIDER = 341;
    uint256 internal constant INVALID_INITIALIZATION = 342;
    uint256 internal constant OUT_OF_NEW_TARGET_RANGE = 343;
    uint256 internal constant FEATURE_DISABLED = 344;
    uint256 internal constant UNINITIALIZED_POOL_CONTROLLER = 345;
    uint256 internal constant SET_SWAP_FEE_DURING_FEE_CHANGE = 346;
    uint256 internal constant SET_SWAP_FEE_PENDING_FEE_CHANGE = 347;
    uint256 internal constant CHANGE_TOKENS_DURING_WEIGHT_CHANGE = 348;
    uint256 internal constant CHANGE_TOKENS_PENDING_WEIGHT_CHANGE = 349;
    uint256 internal constant MAX_WEIGHT = 350;
    uint256 internal constant UNAUTHORIZED_JOIN = 351;
    uint256 internal constant MAX_MANAGEMENT_AUM_FEE_PERCENTAGE = 352;
    uint256 internal constant FRACTIONAL_TARGET = 353;
    // Lib
    uint256 internal constant REENTRANCY = 400;
    uint256 internal constant SENDER_NOT_ALLOWED = 401;
    uint256 internal constant PAUSED = 402;
    uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
    uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
    uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
    uint256 internal constant INSUFFICIENT_BALANCE = 406;
    uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
    uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
    uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
    uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
    uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
    uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
    uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
    uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
    uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
    uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
    uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
    uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
    uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
    uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
    uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
    uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
    uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
    uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
    uint256 internal constant CALLER_IS_NOT_OWNER = 426;
    uint256 internal constant NEW_OWNER_IS_ZERO = 427;
    uint256 internal constant CODE_DEPLOYMENT_FAILED = 428;
    uint256 internal constant CALL_TO_NON_CONTRACT = 429;
    uint256 internal constant LOW_LEVEL_CALL_FAILED = 430;
    uint256 internal constant NOT_PAUSED = 431;
    uint256 internal constant ADDRESS_ALREADY_ALLOWLISTED = 432;
    uint256 internal constant ADDRESS_NOT_ALLOWLISTED = 433;
    uint256 internal constant ERC20_BURN_EXCEEDS_BALANCE = 434;
    uint256 internal constant INVALID_OPERATION = 435;
    uint256 internal constant CODEC_OVERFLOW = 436;
    uint256 internal constant IN_RECOVERY_MODE = 437;
    uint256 internal constant NOT_IN_RECOVERY_MODE = 438;
    uint256 internal constant INDUCED_FAILURE = 439;
    uint256 internal constant EXPIRED_SIGNATURE = 440;
    uint256 internal constant MALFORMED_SIGNATURE = 441;
    uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_UINT64 = 442;
    uint256 internal constant UNHANDLED_FEE_TYPE = 443;
    // Vault
    uint256 internal constant INVALID_POOL_ID = 500;
    uint256 internal constant CALLER_NOT_POOL = 501;
    uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
    uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
    uint256 internal constant INVALID_SIGNATURE = 504;
    uint256 internal constant EXIT_BELOW_MIN = 505;
    uint256 internal constant JOIN_ABOVE_MAX = 506;
    uint256 internal constant SWAP_LIMIT = 507;
    uint256 internal constant SWAP_DEADLINE = 508;
    uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
    uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
    uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
    uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
    uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
    uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
    uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
    uint256 internal constant INSUFFICIENT_ETH = 516;
    uint256 internal constant UNALLOCATED_ETH = 517;
    uint256 internal constant ETH_TRANSFER = 518;
    uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
    uint256 internal constant TOKENS_MISMATCH = 520;
    uint256 internal constant TOKEN_NOT_REGISTERED = 521;
    uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
    uint256 internal constant TOKENS_ALREADY_SET = 523;
    uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
    uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
    uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
    uint256 internal constant POOL_NO_TOKENS = 527;
    uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;
    // Fees
    uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
    uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
    uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
    uint256 internal constant AUM_FEE_PERCENTAGE_TOO_HIGH = 603;
    // Misc
    uint256 internal constant UNIMPLEMENTED = 998;
    uint256 internal constant SHOULD_NOT_HAPPEN = 999;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/IAuthentication.sol";
/**
 * @dev Building block for performing access control on external functions.
 *
 * This contract is used via the `authenticate` modifier (or the `_authenticateCaller` function), which can be applied
 * to external functions to only make them callable by authorized accounts.
 *
 * Derived contracts must implement the `_canPerform` function, which holds the actual access control logic.
 */
abstract contract Authentication is IAuthentication {
    bytes32 private immutable _actionIdDisambiguator;
    /**
     * @dev The main purpose of the `actionIdDisambiguator` is to prevent accidental function selector collisions in
     * multi contract systems.
     *
     * There are two main uses for it:
     *  - if the contract is a singleton, any unique identifier can be used to make the associated action identifiers
     *    unique. The contract's own address is a good option.
     *  - if the contract belongs to a family that shares action identifiers for the same functions, an identifier
     *    shared by the entire family (and no other contract) should be used instead.
     */
    constructor(bytes32 actionIdDisambiguator) {
        _actionIdDisambiguator = actionIdDisambiguator;
    }
    /**
     * @dev Reverts unless the caller is allowed to call this function. Should only be applied to external functions.
     */
    modifier authenticate() {
        _authenticateCaller();
        _;
    }
    /**
     * @dev Reverts unless the caller is allowed to call the entry point function.
     */
    function _authenticateCaller() internal view {
        bytes32 actionId = getActionId(msg.sig);
        _require(_canPerform(actionId, msg.sender), Errors.SENDER_NOT_ALLOWED);
    }
    function getActionId(bytes4 selector) public view override returns (bytes32) {
        // Each external function is dynamically assigned an action identifier as the hash of the disambiguator and the
        // function selector. Disambiguation is necessary to avoid potential collisions in the function selectors of
        // multiple contracts.
        return keccak256(abi.encodePacked(_actionIdDisambiguator, selector));
    }
    function _canPerform(bytes32 actionId, address user) internal view virtual returns (bool);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
library StablePoolUserData {
    enum JoinKind { INIT, EXACT_TOKENS_IN_FOR_BPT_OUT, TOKEN_IN_FOR_EXACT_BPT_OUT, ALL_TOKENS_IN_FOR_EXACT_BPT_OUT }
    enum ExitKind { EXACT_BPT_IN_FOR_ONE_TOKEN_OUT, BPT_IN_FOR_EXACT_TOKENS_OUT, EXACT_BPT_IN_FOR_ALL_TOKENS_OUT }
    function joinKind(bytes memory self) internal pure returns (JoinKind) {
        return abi.decode(self, (JoinKind));
    }
    function exitKind(bytes memory self) internal pure returns (ExitKind) {
        return abi.decode(self, (ExitKind));
    }
    // Joins
    function initialAmountsIn(bytes memory self) internal pure returns (uint256[] memory amountsIn) {
        (, amountsIn) = abi.decode(self, (JoinKind, uint256[]));
    }
    function exactTokensInForBptOut(bytes memory self)
        internal
        pure
        returns (uint256[] memory amountsIn, uint256 minBPTAmountOut)
    {
        (, amountsIn, minBPTAmountOut) = abi.decode(self, (JoinKind, uint256[], uint256));
    }
    function tokenInForExactBptOut(bytes memory self) internal pure returns (uint256 bptAmountOut, uint256 tokenIndex) {
        (, bptAmountOut, tokenIndex) = abi.decode(self, (JoinKind, uint256, uint256));
    }
    function allTokensInForExactBptOut(bytes memory self) internal pure returns (uint256 bptAmountOut) {
        (, bptAmountOut) = abi.decode(self, (JoinKind, uint256));
    }
    // Exits
    function exactBptInForTokenOut(bytes memory self) internal pure returns (uint256 bptAmountIn, uint256 tokenIndex) {
        (, bptAmountIn, tokenIndex) = abi.decode(self, (ExitKind, uint256, uint256));
    }
    function exactBptInForTokensOut(bytes memory self) internal pure returns (uint256 bptAmountIn) {
        (, bptAmountIn) = abi.decode(self, (ExitKind, uint256));
    }
    function bptInForExactTokensOut(bytes memory self)
        internal
        pure
        returns (uint256[] memory amountsOut, uint256 maxBPTAmountIn)
    {
        (, amountsOut, maxBPTAmountIn) = abi.decode(self, (ExitKind, uint256[], uint256));
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
interface IRateProvider {
    /**
     * @dev Returns an 18 decimal fixed point number that is the exchange rate of the token to some other underlying
     * token. The meaning of this rate depends on the context.
     */
    function getRate() external view returns (uint256);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "./LogExpMath.sol";
/* solhint-disable private-vars-leading-underscore */
library FixedPoint {
    uint256 internal constant ONE = 1e18; // 18 decimal places
    uint256 internal constant TWO = 2 * ONE;
    uint256 internal constant FOUR = 4 * ONE;
    uint256 internal constant MAX_POW_RELATIVE_ERROR = 10000; // 10^(-14)
    // Minimum base for the power function when the exponent is 'free' (larger than ONE).
    uint256 internal constant MIN_POW_BASE_FREE_EXPONENT = 0.7e18;
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        // Fixed Point addition is the same as regular checked addition
        uint256 c = a + b;
        _require(c >= a, Errors.ADD_OVERFLOW);
        return c;
    }
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        // Fixed Point addition is the same as regular checked addition
        _require(b <= a, Errors.SUB_OVERFLOW);
        uint256 c = a - b;
        return c;
    }
    function mulDown(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 product = a * b;
        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
        return product / ONE;
    }
    function mulUp(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 product = a * b;
        _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
        if (product == 0) {
            return 0;
        } else {
            // The traditional divUp formula is:
            // divUp(x, y) := (x + y - 1) / y
            // To avoid intermediate overflow in the addition, we distribute the division and get:
            // divUp(x, y) := (x - 1) / y + 1
            // Note that this requires x != 0, which we already tested for.
            return ((product - 1) / ONE) + 1;
        }
    }
    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        if (a == 0) {
            return 0;
        } else {
            uint256 aInflated = a * ONE;
            _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
            return aInflated / b;
        }
    }
    function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        if (a == 0) {
            return 0;
        } else {
            uint256 aInflated = a * ONE;
            _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
            // The traditional divUp formula is:
            // divUp(x, y) := (x + y - 1) / y
            // To avoid intermediate overflow in the addition, we distribute the division and get:
            // divUp(x, y) := (x - 1) / y + 1
            // Note that this requires x != 0, which we already tested for.
            return ((aInflated - 1) / b) + 1;
        }
    }
    /**
     * @dev Returns x^y, assuming both are fixed point numbers, rounding down. The result is guaranteed to not be above
     * the true value (that is, the error function expected - actual is always positive).
     */
    function powDown(uint256 x, uint256 y) internal pure returns (uint256) {
        // Optimize for when y equals 1.0, 2.0 or 4.0, as those are very simple to implement and occur often in 50/50
        // and 80/20 Weighted Pools
        if (y == ONE) {
            return x;
        } else if (y == TWO) {
            return mulDown(x, x);
        } else if (y == FOUR) {
            uint256 square = mulDown(x, x);
            return mulDown(square, square);
        } else {
            uint256 raw = LogExpMath.pow(x, y);
            uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
            if (raw < maxError) {
                return 0;
            } else {
                return sub(raw, maxError);
            }
        }
    }
    /**
     * @dev Returns x^y, assuming both are fixed point numbers, rounding up. The result is guaranteed to not be below
     * the true value (that is, the error function expected - actual is always negative).
     */
    function powUp(uint256 x, uint256 y) internal pure returns (uint256) {
        // Optimize for when y equals 1.0, 2.0 or 4.0, as those are very simple to implement and occur often in 50/50
        // and 80/20 Weighted Pools
        if (y == ONE) {
            return x;
        } else if (y == TWO) {
            return mulUp(x, x);
        } else if (y == FOUR) {
            uint256 square = mulUp(x, x);
            return mulUp(square, square);
        } else {
            uint256 raw = LogExpMath.pow(x, y);
            uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
            return add(raw, maxError);
        }
    }
    /**
     * @dev Returns the complement of a value (1 - x), capped to 0 if x is larger than 1.
     *
     * Useful when computing the complement for values with some level of relative error, as it strips this error and
     * prevents intermediate negative values.
     */
    function complement(uint256 x) internal pure returns (uint256) {
        return (x < ONE) ? (ONE - x) : 0;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
 * Adapted from OpenZeppelin's SafeMath library.
 */
library Math {
    /**
     * @dev Returns the absolute value of a signed integer.
     */
    function abs(int256 a) internal pure returns (uint256) {
        return a > 0 ? uint256(a) : uint256(-a);
    }
    /**
     * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        _require(c >= a, Errors.ADD_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the addition of two signed integers, reverting on overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b <= a, Errors.SUB_OVERFLOW);
        uint256 c = a - b;
        return c;
    }
    /**
     * @dev Returns the subtraction of two signed integers, reverting on overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the largest of two numbers of 256 bits.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }
    /**
     * @dev Returns the smallest of two numbers of 256 bits.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a * b;
        _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
        return c;
    }
    function div(
        uint256 a,
        uint256 b,
        bool roundUp
    ) internal pure returns (uint256) {
        return roundUp ? divUp(a, b) : divDown(a, b);
    }
    function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        return a / b;
    }
    function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
        _require(b != 0, Errors.ZERO_DIVISION);
        if (a == 0) {
            return 0;
        } else {
            return 1 + (a - 1) / b;
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
import "@balancer-labs/v2-interfaces/contracts/vault/IAsset.sol";
// solhint-disable
function _asIAsset(IERC20[] memory tokens) pure returns (IAsset[] memory assets) {
    // solhint-disable-next-line no-inline-assembly
    assembly {
        assets := tokens
    }
}
function _sortTokens(
    IERC20 tokenA,
    IERC20 tokenB,
    IERC20 tokenC
) pure returns (IERC20[] memory tokens) {
    (uint256 indexTokenA, uint256 indexTokenB, uint256 indexTokenC) = _getSortedTokenIndexes(tokenA, tokenB, tokenC);
    tokens = new IERC20[](3);
    tokens[indexTokenA] = tokenA;
    tokens[indexTokenB] = tokenB;
    tokens[indexTokenC] = tokenC;
}
function _insertSorted(IERC20[] memory tokens, IERC20 token) pure returns (IERC20[] memory sorted) {
    sorted = new IERC20[](tokens.length + 1);
    if (tokens.length == 0) {
        sorted[0] = token;
        return sorted;
    }
    uint256 i;
    for (i = tokens.length; i > 0 && tokens[i - 1] > token; i--) sorted[i] = tokens[i - 1];
    for (uint256 j = 0; j < i; j++) sorted[j] = tokens[j];
    sorted[i] = token;
}
function _appendToken(IERC20[] memory tokens, IERC20 newToken) pure returns (IERC20[] memory newTokens) {
    uint256 numTokens = tokens.length;
    newTokens = new IERC20[](numTokens + 1);
    for (uint256 i = 0; i < numTokens; ++i) newTokens[i] = tokens[i];
    newTokens[numTokens] = newToken;
}
function _findTokenIndex(IERC20[] memory tokens, IERC20 token) pure returns (uint256) {
    // Note that while we know tokens are initially sorted, we cannot assume this will hold throughout
    // the pool's lifetime, as pools with mutable tokens can append and remove tokens in any order.
    uint256 tokensLength = tokens.length;
    for (uint256 i = 0; i < tokensLength; i++) {
        if (tokens[i] == token) {
            return i;
        }
    }
    _revert(Errors.INVALID_TOKEN);
}
function _getSortedTokenIndexes(
    IERC20 tokenA,
    IERC20 tokenB,
    IERC20 tokenC
)
    pure
    returns (
        uint256 indexTokenA,
        uint256 indexTokenB,
        uint256 indexTokenC
    )
{
    if (tokenA < tokenB) {
        if (tokenB < tokenC) {
            // (tokenA, tokenB, tokenC)
            return (0, 1, 2);
        } else if (tokenA < tokenC) {
            // (tokenA, tokenC, tokenB)
            return (0, 2, 1);
        } else {
            // (tokenC, tokenA, tokenB)
            return (1, 2, 0);
        }
    } else {
        // tokenB < tokenA
        if (tokenC < tokenB) {
            // (tokenC, tokenB, tokenA)
            return (2, 1, 0);
        } else if (tokenC < tokenA) {
            // (tokenB, tokenC, tokenA)
            return (2, 0, 1);
        } else {
            // (tokenB, tokenA, tokenC)
            return (1, 0, 2);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
library InputHelpers {
    function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
        _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
    }
    function ensureInputLengthMatch(
        uint256 a,
        uint256 b,
        uint256 c
    ) internal pure {
        _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
    }
    function ensureArrayIsSorted(IERC20[] memory array) internal pure {
        address[] memory addressArray;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            addressArray := array
        }
        ensureArrayIsSorted(addressArray);
    }
    function ensureArrayIsSorted(address[] memory array) internal pure {
        if (array.length < 2) {
            return;
        }
        address previous = array[0];
        for (uint256 i = 1; i < array.length; ++i) {
            address current = array[i];
            _require(previous < current, Errors.UNSORTED_ARRAY);
            previous = current;
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "@balancer-labs/v2-interfaces/contracts/vault/IGeneralPool.sol";
import "./BasePool.sol";
/**
 * @dev Extension of `BasePool`, adding a handler for `IGeneralPool.onSwap`.
 *
 * Derived contracts must call `BasePool`'s constructor, and implement `_onSwapGivenIn` and `_onSwapGivenOut` along with
 * `BasePool`'s virtual functions. Inheriting from this contract lets derived contracts choose the General
 * specialization setting.
 */
abstract contract BaseGeneralPool is IGeneralPool, BasePool {
    // Swap Hooks
    function onSwap(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut
    ) external override onlyVault(swapRequest.poolId) returns (uint256) {
        _beforeSwapJoinExit();
        _validateIndexes(indexIn, indexOut, _getTotalTokens());
        uint256[] memory scalingFactors = _scalingFactors();
        return
            swapRequest.kind == IVault.SwapKind.GIVEN_IN
                ? _swapGivenIn(swapRequest, balances, indexIn, indexOut, scalingFactors)
                : _swapGivenOut(swapRequest, balances, indexIn, indexOut, scalingFactors);
    }
    function _swapGivenIn(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut,
        uint256[] memory scalingFactors
    ) internal virtual returns (uint256) {
        // Fees are subtracted before scaling, to reduce the complexity of the rounding direction analysis.
        swapRequest.amount = _subtractSwapFeeAmount(swapRequest.amount);
        _upscaleArray(balances, scalingFactors);
        swapRequest.amount = _upscale(swapRequest.amount, scalingFactors[indexIn]);
        uint256 amountOut = _onSwapGivenIn(swapRequest, balances, indexIn, indexOut);
        // amountOut tokens are exiting the Pool, so we round down.
        return _downscaleDown(amountOut, scalingFactors[indexOut]);
    }
    function _swapGivenOut(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut,
        uint256[] memory scalingFactors
    ) internal virtual returns (uint256) {
        _upscaleArray(balances, scalingFactors);
        swapRequest.amount = _upscale(swapRequest.amount, scalingFactors[indexOut]);
        uint256 amountIn = _onSwapGivenOut(swapRequest, balances, indexIn, indexOut);
        // amountIn tokens are entering the Pool, so we round up.
        amountIn = _downscaleUp(amountIn, scalingFactors[indexIn]);
        // Fees are added after scaling happens, to reduce the complexity of the rounding direction analysis.
        return _addSwapFeeAmount(amountIn);
    }
    /*
     * @dev Called when a swap with the Pool occurs, where the amount of tokens entering the Pool is known.
     *
     * Returns the amount of tokens that will be taken from the Pool in return.
     *
     * All amounts inside `swapRequest` and `balances` are upscaled. The swap fee has already been deducted from
     * `swapRequest.amount`.
     *
     * The return value is also considered upscaled, and will be downscaled (rounding down) before returning it to the
     * Vault.
     */
    function _onSwapGivenIn(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut
    ) internal virtual returns (uint256);
    /*
     * @dev Called when a swap with the Pool occurs, where the amount of tokens exiting the Pool is known.
     *
     * Returns the amount of tokens that will be granted to the Pool in return.
     *
     * All amounts inside `swapRequest` and `balances` are upscaled.
     *
     * The return value is also considered upscaled, and will be downscaled (rounding up) before applying the swap fee
     * and returning it to the Vault.
     */
    function _onSwapGivenOut(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut
    ) internal virtual returns (uint256);
    function _validateIndexes(
        uint256 indexIn,
        uint256 indexOut,
        uint256 limit
    ) private pure {
        _require(indexIn < limit && indexOut < limit, Errors.OUT_OF_BOUNDS);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
/**
 * Price rate caches are used to avoid querying the price rate for a token every time we need to work with it. It is
 * useful for slow changing rates, such as those that arise from interest-bearing tokens (e.g. waDAI into DAI).
 *
 * The cache data is packed into a single bytes32 value with the following structure:
 * [ 32 bits |  32 bits  |  96 bits  |    96 bits    ]
 * [ expires | duration  | old rate  | current rate  ]
 * |MSB                                           LSB|
 *
 * 'rate' is an 18 decimal fixed point number, supporting rates of up to ~3e10. 'expires' is a Unix timestamp, and
 * 'duration' is expressed in seconds.
 */
library PriceRateCache {
    using WordCodec for bytes32;
    uint256 private constant _CURRENT_PRICE_RATE_OFFSET = 0;
    uint256 private constant _OLD_PRICE_RATE_OFFSET = 96;
    uint256 private constant _PRICE_RATE_CACHE_DURATION_OFFSET = 192;
    uint256 private constant _PRICE_RATE_CACHE_EXPIRES_OFFSET = 224;
    uint256 private constant _RATE_BIT_LENGTH = 96;
    uint256 private constant _DURATION_BIT_LENGTH = 32;
    /**
     * @dev Returns the current rate in the price rate cache.
     */
    function getCurrentRate(bytes32 cache) internal pure returns (uint256) {
        return cache.decodeUint(_CURRENT_PRICE_RATE_OFFSET, _RATE_BIT_LENGTH);
    }
    /**
     * @dev Returns the old rate in the price rate cache.
     */
    function getOldRate(bytes32 cache) internal pure returns (uint256) {
        return cache.decodeUint(_OLD_PRICE_RATE_OFFSET, _RATE_BIT_LENGTH);
    }
    /**
     * @dev Copies the current rate to the old rate.
     */
    function updateOldRate(bytes32 cache) internal pure returns (bytes32) {
        return cache.insertUint(getCurrentRate(cache), _OLD_PRICE_RATE_OFFSET, _RATE_BIT_LENGTH);
    }
    /**
     * @dev Returns the duration of a price rate cache.
     */
    function getDuration(bytes32 cache) internal pure returns (uint256) {
        return cache.decodeUint(_PRICE_RATE_CACHE_DURATION_OFFSET, _DURATION_BIT_LENGTH);
    }
    /**
     * @dev Returns the duration and expiration time of a price rate cache.
     */
    function getTimestamps(bytes32 cache) internal pure returns (uint256 duration, uint256 expires) {
        duration = getDuration(cache);
        expires = cache.decodeUint(_PRICE_RATE_CACHE_EXPIRES_OFFSET, _DURATION_BIT_LENGTH);
    }
    /**
     * @dev Encodes rate and duration into a price rate cache. The expiration time is computed automatically, counting
     * from the current time.
     */
    function updateRateAndDuration(
        bytes32 cache,
        uint256 rate,
        uint256 duration
    ) internal view returns (bytes32) {
        _require(rate >> _RATE_BIT_LENGTH == 0, Errors.PRICE_RATE_OVERFLOW);
        // solhint-disable not-rely-on-time
        return
            cache
                .insertUint(rate, _CURRENT_PRICE_RATE_OFFSET, _RATE_BIT_LENGTH)
                .insertUint(duration, _PRICE_RATE_CACHE_DURATION_OFFSET, _DURATION_BIT_LENGTH)
                .insertUint(block.timestamp + duration, _PRICE_RATE_CACHE_EXPIRES_OFFSET, _DURATION_BIT_LENGTH);
    }
    /**
     * @dev Update the current rate in a price rate cache.
     */
    function updateCurrentRate(bytes32 cache, uint256 rate) internal pure returns (bytes32) {
        _require(rate >> _RATE_BIT_LENGTH == 0, Errors.PRICE_RATE_OVERFLOW);
        return cache.insertUint(rate, _CURRENT_PRICE_RATE_OFFSET, _RATE_BIT_LENGTH);
    }
    /**
     * @dev Update the duration (and expiration) in a price rate cache.
     */
    function updateDuration(bytes32 cache, uint256 duration) internal view returns (bytes32) {
        return
            cache.insertUint(duration, _PRICE_RATE_CACHE_DURATION_OFFSET, _DURATION_BIT_LENGTH).insertUint(
                block.timestamp + duration,
                _PRICE_RATE_CACHE_EXPIRES_OFFSET,
                _DURATION_BIT_LENGTH
            );
    }
    /**
     * @dev Returns rate, duration and expiration time of a price rate cache.
     */
    function decode(bytes32 cache)
        internal
        pure
        returns (
            uint256 rate,
            uint256 duration,
            uint256 expires
        )
    {
        rate = getCurrentRate(cache);
        (duration, expires) = getTimestamps(cache);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IRateProvider.sol";
import "@balancer-labs/v2-pool-utils/contracts/BasePool.sol";
import "./StableMath.sol";
abstract contract ComposableStablePoolStorage is BasePool {
    using FixedPoint for uint256;
    using WordCodec for bytes32;
    struct StorageParams {
        IERC20[] registeredTokens;
        IRateProvider[] tokenRateProviders;
        bool exemptFromYieldProtocolFeeFlag;
    }
    // This minimum refers not to the total tokens, but rather to the non-BPT tokens. The minimum value for _totalTokens
    // is therefore _MIN_NON_BPT_TOKENS + 1.
    uint256 private constant _MIN_NON_BPT_TOKENS = 2;
    // The Pool will register n+1 tokens, where n are the actual tokens in the Pool, and the other one is the BPT
    // itself.
    uint256 private immutable _totalTokens;
    // The index of BPT in the tokens and balances arrays, i.e. its index when calling IVault.registerTokens().
    uint256 private immutable _bptIndex;
    // These are the registered tokens: one of them will be the BPT.
    IERC20 private immutable _token0;
    IERC20 private immutable _token1;
    IERC20 private immutable _token2;
    IERC20 private immutable _token3;
    IERC20 private immutable _token4;
    IERC20 private immutable _token5;
    // All token balances are normalized to behave as if the token had 18 decimals. We assume a token's decimals will
    // not change throughout its lifetime, and store the corresponding scaling factor for each at construction time.
    // These factors are always greater than or equal to one: tokens with more than 18 decimals are not supported.
    uint256 internal immutable _scalingFactor0;
    uint256 internal immutable _scalingFactor1;
    uint256 internal immutable _scalingFactor2;
    uint256 internal immutable _scalingFactor3;
    uint256 internal immutable _scalingFactor4;
    uint256 internal immutable _scalingFactor5;
    // Rate Providers accommodate tokens with a known price ratio, such as Compound's cTokens.
    IRateProvider internal immutable _rateProvider0;
    IRateProvider internal immutable _rateProvider1;
    IRateProvider internal immutable _rateProvider2;
    IRateProvider internal immutable _rateProvider3;
    IRateProvider internal immutable _rateProvider4;
    IRateProvider internal immutable _rateProvider5;
    // This is a bitmap which allows querying whether a token at a particular index:
    // - has a rate provider associated with it.
    // - is exempt from yield protocol fees.
    // This is required as the data stored in this bitmap is computed from values in immutable storage,
    // without this bitmap we would have to manually search through token by token to reach these values.
    // The data structure is as follows:
    //
    // [  unused  | rate provider flags | exemption flags ]
    // [ 244 bits |        6 bits       |     6 bits      ]
    bytes32 private immutable _rateProviderInfoBitmap;
    // Indicates whether all the tokens from the pool are exempt from yield protocol fee or not.
    bool private immutable _exemptFromYieldProtocolFee;
    uint256 private constant _RATE_PROVIDER_FLAGS_OFFSET = 6;
    constructor(StorageParams memory params) {
        // BasePool checks that the Pool has at least two tokens, but since one of them is the BPT (this contract), we
        // need to check ourselves that there are at least creator-supplied tokens (i.e. the minimum number of total
        // tokens for this contract is actually three, including the BPT).
        uint256 totalTokens = params.registeredTokens.length;
        _require(totalTokens > _MIN_NON_BPT_TOKENS, Errors.MIN_TOKENS);
        InputHelpers.ensureInputLengthMatch(totalTokens - 1, params.tokenRateProviders.length);
        _totalTokens = totalTokens;
        // Immutable variables cannot be initialized inside an if statement, so we must do conditional assignments
        _token0 = params.registeredTokens[0];
        _token1 = params.registeredTokens[1];
        _token2 = params.registeredTokens[2];
        _token3 = totalTokens > 3 ? params.registeredTokens[3] : IERC20(0);
        _token4 = totalTokens > 4 ? params.registeredTokens[4] : IERC20(0);
        _token5 = totalTokens > 5 ? params.registeredTokens[5] : IERC20(0);
        _scalingFactor0 = _computeScalingFactor(params.registeredTokens[0]);
        _scalingFactor1 = _computeScalingFactor(params.registeredTokens[1]);
        _scalingFactor2 = _computeScalingFactor(params.registeredTokens[2]);
        _scalingFactor3 = totalTokens > 3 ? _computeScalingFactor(params.registeredTokens[3]) : 0;
        _scalingFactor4 = totalTokens > 4 ? _computeScalingFactor(params.registeredTokens[4]) : 0;
        _scalingFactor5 = totalTokens > 5 ? _computeScalingFactor(params.registeredTokens[5]) : 0;
        // The Vault keeps track of all Pool tokens in a specific order: we need to know what the index of BPT is in
        // this ordering to be able to identify it when balances arrays are received. Since the tokens array is sorted,
        // we need to find the correct BPT index in the array returned by `_insertSorted()`.
        // See `IVault.getPoolTokens()` for more information regarding token ordering.
        uint256 bptIndex;
        for (
            bptIndex = params.registeredTokens.length - 1;
            bptIndex > 0 && params.registeredTokens[bptIndex] > IERC20(this);
            bptIndex--
        ) {
            // solhint-disable-previous-line no-empty-blocks
        }
        _bptIndex = bptIndex;
        // The rate providers are stored as immutable state variables, and for simplicity when accessing those we'll
        // reference them by token index in the full base tokens plus BPT set (i.e. the tokens the Pool registers). Due
        // to immutable variables requiring an explicit assignment instead of defaulting to an empty value, it is
        // simpler to create a new memory array with the values we want to assign to the immutable state variables.
        IRateProvider[] memory rateProviders = new IRateProvider[](params.registeredTokens.length);
        bytes32 rateProviderInfoBitmap;
        // The exemptFromYieldFlag should never be set on a token without a rate provider.
        // This would cause division by zero errors downstream.
        for (uint256 i = 0; i < params.registeredTokens.length; ++i) {
            if (i < bptIndex) {
                rateProviders[i] = params.tokenRateProviders[i];
            } else if (i != bptIndex) {
                rateProviders[i] = params.tokenRateProviders[i - 1];
            } else {
                // do nothing for i == bptIndex
                continue;
            }
            // Store whether token has rate provider
            rateProviderInfoBitmap = rateProviderInfoBitmap.insertBool(
                rateProviders[i] != IRateProvider(0),
                _RATE_PROVIDER_FLAGS_OFFSET + i
            );
            // Store whether token is exempt from yield fees (only with rate providers).
            if (params.exemptFromYieldProtocolFeeFlag && rateProviders[i] != IRateProvider(0)) {
                rateProviderInfoBitmap = rateProviderInfoBitmap.insertBool(true, i);
            }
        }
        // Either all tokens are exempt, or none of them are. This is defined by the input parameter.
        _exemptFromYieldProtocolFee = params.exemptFromYieldProtocolFeeFlag;
        // Immutable variables cannot be initialized inside an if statement, so we must do conditional assignments
        _rateProvider0 = rateProviders[0];
        _rateProvider1 = rateProviders[1];
        _rateProvider2 = rateProviders[2];
        _rateProvider3 = (rateProviders.length > 3) ? rateProviders[3] : IRateProvider(0);
        _rateProvider4 = (rateProviders.length > 4) ? rateProviders[4] : IRateProvider(0);
        _rateProvider5 = (rateProviders.length > 5) ? rateProviders[5] : IRateProvider(0);
        _rateProviderInfoBitmap = rateProviderInfoBitmap;
    }
    // Tokens
    function _getTotalTokens() internal view virtual override returns (uint256) {
        return _totalTokens;
    }
    function _getMaxTokens() internal pure override returns (uint256) {
        // The BPT will be one of the Pool tokens, but it is unaffected by the Stable 5 token limit.
        return StableMath._MAX_STABLE_TOKENS + 1;
    }
    function getBptIndex() public view returns (uint256) {
        return _bptIndex;
    }
    function _getTokenIndex(IERC20 token) internal view returns (uint256) {
        if (token == _token0) return 0;
        if (token == _token1) return 1;
        if (token == _token2) return 2;
        if (token == _token3) return 3;
        if (token == _token4) return 4;
        if (token == _token5) return 5;
        _revert(Errors.INVALID_TOKEN);
    }
    function _scalingFactor(IERC20) internal view virtual override returns (uint256) {
        // We never use a single token's scaling factor by itself, we always process the entire array at once.
        // Therefore we don't bother providing an implementation for this.
        _revert(Errors.UNIMPLEMENTED);
    }
    // Index helpers
    // Convert from an index into an array including BPT (the Vault's registered token list), to an index
    // into an array excluding BPT (usually from user input, such as amountsIn/Out).
    // `index` must not be the BPT token index itself.
    function _skipBptIndex(uint256 index) internal view returns (uint256) {
        // Currently this is never called with an index passed in from user input, so this check
        // should not be necessary. Included for completion (and future proofing).
        _require(index != getBptIndex(), Errors.OUT_OF_BOUNDS);
        return index < getBptIndex() ? index : index.sub(1);
    }
    /**
     * @dev Remove the item at `_bptIndex` from an arbitrary array (e.g., amountsIn).
     */
    function _dropBptItem(uint256[] memory amounts) internal view returns (uint256[] memory) {
        uint256[] memory amountsWithoutBpt = new uint256[](amounts.length - 1);
        for (uint256 i = 0; i < amountsWithoutBpt.length; i++) {
            amountsWithoutBpt[i] = amounts[i < getBptIndex() ? i : i + 1];
        }
        return amountsWithoutBpt;
    }
    /**
     * @dev Same as `_dropBptItem`, except the virtual supply is also returned, and `balances` is assumed to be the
     * current Pool balances (including BPT).
     */
    function _dropBptItemFromBalances(uint256[] memory registeredBalances)
        internal
        view
        returns (uint256, uint256[] memory)
    {
        return (_getVirtualSupply(registeredBalances[getBptIndex()]), _dropBptItem(registeredBalances));
    }
    // Convert from an index into an array excluding BPT (usually from user input, such as amountsIn/Out),
    // to an index into an array including BPT (the Vault's registered token list).
    // `index` must not be the BPT token index itself, if it is the last element, and the result must be
    // in the range of registered tokens.
    function _addBptIndex(uint256 index) internal view returns (uint256 registeredIndex) {
        // This can be called from an index passed in from user input.
        registeredIndex = index < getBptIndex() ? index : index.add(1);
        // TODO: `indexWithBpt != getBptIndex()` follows from above line and so can be removed.
        _require(registeredIndex < _totalTokens && registeredIndex != getBptIndex(), Errors.OUT_OF_BOUNDS);
    }
    /**
     * @dev Take an array of arbitrary values the size of the token set without BPT, and insert the given
     * bptAmount at the bptIndex location.
     *
     * The caller is responsible for ensuring the `amounts` input array is sized properly; this function
     * performs no checks.
     */
    function _addBptItem(uint256[] memory amounts, uint256 bptAmount)
        internal
        view
        returns (uint256[] memory registeredTokenAmounts)
    {
        registeredTokenAmounts = new uint256[](amounts.length + 1);
        for (uint256 i = 0; i < registeredTokenAmounts.length; i++) {
            registeredTokenAmounts[i] = i == getBptIndex() ? bptAmount : amounts[i < getBptIndex() ? i : i - 1];
        }
    }
    // Rate Providers
    function _getScalingFactor(uint256 index) internal view returns (uint256) {
        if (index == 0) return _scalingFactor0;
        if (index == 1) return _scalingFactor1;
        if (index == 2) return _scalingFactor2;
        if (index == 3) return _scalingFactor3;
        if (index == 4) return _scalingFactor4;
        if (index == 5) return _scalingFactor5;
        else {
            _revert(Errors.INVALID_TOKEN);
        }
    }
    /**
     * @dev Returns the rate providers configured for each token (in the same order as registered).
     */
    function getRateProviders() external view returns (IRateProvider[] memory) {
        uint256 totalTokens = _getTotalTokens();
        IRateProvider[] memory providers = new IRateProvider[](totalTokens);
        for (uint256 i = 0; i < totalTokens; ++i) {
            providers[i] = _getRateProvider(i);
        }
        return providers;
    }
    function _getRateProvider(uint256 index) internal view returns (IRateProvider) {
        if (index == 0) return _rateProvider0;
        if (index == 1) return _rateProvider1;
        if (index == 2) return _rateProvider2;
        if (index == 3) return _rateProvider3;
        if (index == 4) return _rateProvider4;
        if (index == 5) return _rateProvider5;
        else {
            _revert(Errors.INVALID_TOKEN);
        }
    }
    /**
     * @notice Return true if the token at this index has a rate provider
     */
    function _hasRateProvider(uint256 tokenIndex) internal view returns (bool) {
        return _rateProviderInfoBitmap.decodeBool(_RATE_PROVIDER_FLAGS_OFFSET + tokenIndex);
    }
    /**
     * @notice Return true if all tokens are exempt from yield fees.
     */
    function isExemptFromYieldProtocolFee() public view returns (bool) {
        return _exemptFromYieldProtocolFee;
    }
    /**
     * @dev Returns whether the token is exempt from protocol fees on the yield.
     * If the BPT token is passed in (which doesn't make much sense, but shouldn't fail,
     * since it is a valid pool token), the corresponding flag will be false.
     */
    function isTokenExemptFromYieldProtocolFee(IERC20 token) external view returns (bool) {
        return _exemptFromYieldProtocolFee && _hasRateProvider(_getTokenIndex(token));
    }
    // Virtual Supply
    /**
     * @dev Returns the number of tokens in circulation.
     *
     * WARNING: in the vast majority of cases this is not a useful value, since it does not include the debt the Pool
     * accrued in the form of unminted BPT for the ProtocolFeesCollector. Look into `getActualSupply()` and how that's
     * different.
     *
     * In other pools, this would be the same as `totalSupply`, but since this pool pre-mints BPT and holds it in the
     * Vault as a token, we need to subtract the Vault's balance to get the total "circulating supply". Both the
     * totalSupply and Vault balance can change. If users join or exit using swaps, some of the preminted BPT are
     * exchanged, so the Vault's balance increases after joins and decreases after exits. If users call the regular
     * joins/exit functions, the totalSupply can change as BPT are minted for joins or burned for exits.
     */
    function _getVirtualSupply(uint256 bptBalance) internal view returns (uint256) {
        // The initial amount of BPT pre-minted is _PREMINTED_TOKEN_BALANCE, and it goes entirely to the pool balance in
        // the vault. So the virtualSupply (the amount of BPT supply in circulation) is defined as:
        // virtualSupply = totalSupply() - _balances[_bptIndex]
        return totalSupply().sub(bptBalance);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IRateProvider.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/ERC20Helpers.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
import "@balancer-labs/v2-pool-utils/contracts/rates/PriceRateCache.sol";
import "./ComposableStablePoolStorage.sol";
abstract contract ComposableStablePoolRates is ComposableStablePoolStorage {
    using PriceRateCache for bytes32;
    using FixedPoint for uint256;
    struct RatesParams {
        IERC20[] tokens;
        IRateProvider[] rateProviders;
        uint256[] tokenRateCacheDurations;
    }
    // Token rate caches are used to avoid querying the price rate for a token every time we need to work with it.
    // The "old rate" field is used for precise protocol fee calculation, to ensure that token yield is only
    // "taxed" once. The data structure is as follows:
    //
    // [ expires | duration | old rate | current rate ]
    // [ uint32  |  uint32  |  uint96  |   uint96     ]
    // Since we never need just one cache but all of them at once, instead of making the mapping go from token address
    // to cache, we go from token index (including BPT), i.e. an array. We use a mapping however instead of a native
    // array to skip the extra read associated with the out-of-bounds check, as we have cheaper ways to guarantee the
    // indices are valid.
    mapping(uint256 => bytes32) internal _tokenRateCaches;
    event TokenRateCacheUpdated(uint256 indexed tokenIndex, uint256 rate);
    event TokenRateProviderSet(uint256 indexed tokenIndex, IRateProvider indexed provider, uint256 cacheDuration);
    constructor(RatesParams memory rateParams) {
        InputHelpers.ensureInputLengthMatch(
            rateParams.tokens.length,
            rateParams.rateProviders.length,
            rateParams.tokenRateCacheDurations.length
        );
        IERC20[] memory registeredTokens = _insertSorted(rateParams.tokens, IERC20(this));
        uint256 bptIndex;
        for (
            bptIndex = registeredTokens.length - 1;
            bptIndex > 0 && registeredTokens[bptIndex] > IERC20(this);
            bptIndex--
        ) {
            // solhint-disable-previous-line no-empty-blocks
        }
        uint256 skipBpt = 0;
        for (uint256 i = 0; i < rateParams.tokens.length; i++) {
            if (i == bptIndex) {
                skipBpt = 1;
            }
            uint256 k = i + skipBpt;
            if (rateParams.rateProviders[i] != IRateProvider(0)) {
                _updateTokenRateCache(k, rateParams.rateProviders[i], rateParams.tokenRateCacheDurations[i]);
                emit TokenRateProviderSet(k, rateParams.rateProviders[i], rateParams.tokenRateCacheDurations[i]);
                // Initialize the old rates as well, in case they are referenced before the first join.
                _updateOldRate(k);
            }
        }
    }
    /**
     * @dev Ensure we are not in a Vault context when this function is called, by attempting a no-op internal
     * balance operation. If we are already in a Vault transaction (e.g., a swap, join, or exit), the Vault's
     * reentrancy protection will cause this function to revert.
     *
     * The exact function call doesn't really matter: we're just trying to trigger the Vault reentrancy check
     * (and not hurt anything in case it works). An empty operation array with no specific operation at all works
     * for that purpose, and is also the least expensive in terms of gas and bytecode size.
     *
     * Use this modifier with any function that can cause a state change in a pool and is either public itself,
     * or called by a public function *outside* a Vault operation (e.g., join, exit, or swap).
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    modifier whenNotInVaultContext() {
        _ensureNotInVaultContext();
        _;
    }
    /**
     * @dev Reverts if called in the middle of a Vault operation; has no effect otherwise.
     */
    function _ensureNotInVaultContext() private {
        IVault.UserBalanceOp[] memory noop = new IVault.UserBalanceOp[](0);
        getVault().manageUserBalance(noop);
    }
    /**
     * @dev Updates the old rate for the token at `index` (including BPT). Assumes `index` is valid.
     */
    function _updateOldRate(uint256 index) internal {
        bytes32 cache = _tokenRateCaches[index];
        _tokenRateCaches[index] = cache.updateOldRate();
    }
    /**
     * @dev Returns the rate for a given token. All token rates are fixed-point values with 18 decimals.
     * If there is no rate provider for the provided token, it returns FixedPoint.ONE.
     */
    function getTokenRate(IERC20 token) external view returns (uint256) {
        return _getTokenRate(_getTokenIndex(token));
    }
    function _getTokenRate(uint256 index) internal view virtual returns (uint256) {
        // We optimize for the scenario where all tokens have rate providers, except the BPT (which never has a rate
        // provider). Therefore, we return early if `token` is the BPT, and otherwise optimistically read the cache
        // expecting that it will not be empty (instead of e.g. fetching the provider to avoid a cache read, since
        // we don't need the provider at all).
        if (index == getBptIndex()) {
            return FixedPoint.ONE;
        }
        bytes32 tokenRateCache = _tokenRateCaches[index];
        return tokenRateCache == bytes32(0) ? FixedPoint.ONE : tokenRateCache.getCurrentRate();
    }
    /**
     * @dev Returns the cached value for token's rate. Reverts if the token doesn't belong to the pool or has no rate
     * provider.
     */
    function getTokenRateCache(IERC20 token)
        external
        view
        returns (
            uint256 rate,
            uint256 oldRate,
            uint256 duration,
            uint256 expires
        )
    {
        bytes32 cache = _tokenRateCaches[_getTokenIndex(token)];
        // A zero cache indicates that the token doesn't have a rate provider associated with it.
        _require(cache != bytes32(0), Errors.TOKEN_DOES_NOT_HAVE_RATE_PROVIDER);
        rate = cache.getCurrentRate();
        oldRate = cache.getOldRate();
        (duration, expires) = cache.getTimestamps();
    }
    /**
     * @dev Sets a new duration for a token rate cache.
     * Note this function also updates the current cached value.
     *
     * This function will revert when called within a Vault context (i.e. in the middle of a join or an exit).
     *
     * This function depends on `getRate` via the rate provider, which may be calculated incorrectly in the middle of a
     * join or an exit because the state of the pool could be out of sync with the state of the Vault.
     *
     * It will also revert if there was no rate provider set initially.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     *
     * @param duration Number of seconds until the current token rate is fetched again.
     */
    function setTokenRateCacheDuration(IERC20 token, uint256 duration) external authenticate whenNotInVaultContext {
        uint256 index = _getTokenIndex(token);
        IRateProvider provider = _getRateProvider(index);
        _require(address(provider) != address(0), Errors.TOKEN_DOES_NOT_HAVE_RATE_PROVIDER);
        _updateTokenRateCache(index, provider, duration);
        emit TokenRateProviderSet(index, provider, duration);
    }
    /**
     * @dev Forces a rate cache hit for a token.
     *
     * This function will revert when called within a Vault context (i.e. in the middle of a join or an exit).
     *
     * This function depends on `getRate` via the rate provider, which may be calculated incorrectly in the middle of a
     * join or an exit because the state of the pool could be out of sync with the state of the Vault.
     *
     * It will also revert if the requested token does not have an associated rate provider.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    function updateTokenRateCache(IERC20 token) external whenNotInVaultContext {
        uint256 index = _getTokenIndex(token);
        IRateProvider provider = _getRateProvider(index);
        _require(address(provider) != address(0), Errors.TOKEN_DOES_NOT_HAVE_RATE_PROVIDER);
        uint256 duration = _tokenRateCaches[index].getDuration();
        _updateTokenRateCache(index, provider, duration);
    }
    /**
     * @dev Internal function to update a token rate cache for a known provider and duration.
     * It trusts the given values, and does not perform any checks.
     */
    function _updateTokenRateCache(
        uint256 index,
        IRateProvider provider,
        uint256 duration
    ) internal virtual {
        uint256 rate = provider.getRate();
        bytes32 cache = _tokenRateCaches[index];
        _tokenRateCaches[index] = cache.updateRateAndDuration(rate, duration);
        emit TokenRateCacheUpdated(index, rate);
    }
    /**
     * @dev Caches the rates of all tokens if necessary
     */
    function _cacheTokenRatesIfNecessary() internal {
        uint256 totalTokens = _getTotalTokens();
        for (uint256 i = 0; i < totalTokens; ++i) {
            _cacheTokenRateIfNecessary(i);
        }
    }
    /**
     * @dev Caches the rate for a token if necessary. It ignores the call if there is no provider set.
     */
    function _cacheTokenRateIfNecessary(uint256 index) internal {
        // We optimize for the scenario where all tokens have rate providers, except the BPT (which never has a rate
        // provider). Therefore, we return early if token is BPT, and otherwise optimistically read the cache expecting
        // that it will not be empty (instead of e.g. fetching the provider to avoid a cache read in situations where
        // we might not need the provider if the cache is still valid).
        if (index == getBptIndex()) return;
        bytes32 cache = _tokenRateCaches[index];
        if (cache != bytes32(0)) {
            (uint256 duration, uint256 expires) = cache.getTimestamps();
            if (block.timestamp > expires) {
                // solhint-disable-previous-line not-rely-on-time
                _updateTokenRateCache(index, _getRateProvider(index), duration);
            }
        }
    }
    // To compute the yield protocol fees, we need the oldRate for all tokens, even if the exempt flag is not set.
    // We do need to ensure the token has a rate provider before updating; otherwise it will not be in the cache.
    function _updateOldRates() internal {
        uint256 totalTokens = _getTotalTokens();
        for (uint256 i = 0; i < totalTokens; ++i) {
            if (_hasRateProvider(i)) _updateOldRate(i);
        }
    }
    /**
     * @dev Apply the token ratios to a set of balances, only if they have a rate provider.
     * The `balances` array is assumed to not include BPT to ensure that token indices align.
     */
    function _getAdjustedBalances(uint256[] memory balances) internal view returns (uint256[] memory) {
        uint256 totalTokensWithoutBpt = balances.length;
        uint256[] memory adjustedBalances = new uint256[](totalTokensWithoutBpt);
        for (uint256 i = 0; i < totalTokensWithoutBpt; ++i) {
            uint256 skipBptIndex = i >= getBptIndex() ? i + 1 : i;
            adjustedBalances[i] = _hasRateProvider(skipBptIndex)
                ? _adjustedBalance(balances[i], _tokenRateCaches[skipBptIndex])
                : balances[i];
        }
        return adjustedBalances;
    }
    // Compute balance * oldRate/currentRate, doing division last to minimize rounding error.
    function _adjustedBalance(uint256 balance, bytes32 cache) private pure returns (uint256) {
        return Math.divDown(Math.mul(balance, cache.getOldRate()), cache.getCurrentRate());
    }
    // Scaling Factors
    /**
     * @dev Overrides scaling factor getter to compute the tokens' rates.
     */
    function _scalingFactors() internal view virtual override returns (uint256[] memory) {
        // There is no need to check the arrays length since both are based on `_getTotalTokens`
        uint256 totalTokens = _getTotalTokens();
        uint256[] memory scalingFactors = new uint256[](totalTokens);
        for (uint256 i = 0; i < totalTokens; ++i) {
            scalingFactors[i] = _getScalingFactor(i).mulDown(_getTokenRate(i));
        }
        return scalingFactors;
    }
    /**
     * @dev Overrides only owner action to allow setting the cache duration for the token rates
     */
    function _isOwnerOnlyAction(bytes32 actionId) internal view virtual override returns (bool) {
        return (actionId == getActionId(this.setTokenRateCacheDuration.selector)) || super._isOwnerOnlyAction(actionId);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
import "@balancer-labs/v2-pool-utils/contracts/protocol-fees/ProtocolFeeCache.sol";
import "@balancer-labs/v2-pool-utils/contracts/protocol-fees/InvariantGrowthProtocolSwapFees.sol";
import "./ComposableStablePoolStorage.sol";
import "./ComposableStablePoolRates.sol";
import "./StableMath.sol";
abstract contract ComposableStablePoolProtocolFees is
    ComposableStablePoolStorage,
    ComposableStablePoolRates,
    ProtocolFeeCache
{
    using FixedPoint for uint256;
    using WordCodec for bytes32;
    // To track protocol fees, we measure and store the value of the invariant after every join and exit.
    // All invariant growth that happens between join and exit events is due to swap fees and yield.
    // For selected tokens, we exclude the yield portion from the computation.
    // Because the invariant depends on the amplification parameter, and this value may change over time, we should only
    // compare invariants that were computed using the same value. We therefore store both values together.
    //
    // These values reside in the same storage slot. The amplification factor is bound by _MAX_AMP * _AMP_PRECISION, or
    // 5e6, which fits in 23 bits. We use all remaining bits for the invariant: this is more than enough, as the
    // invariant is proportional to the total supply, which is capped at 112 bits.
    // The data structure is as follows:
    //
    // [ last join-exit amplification  | last post join-exit invariant ]
    // [           23 bits             |            233 bits           ]
    bytes32 private _lastJoinExitData;
    uint256 private constant _LAST_POST_JOIN_EXIT_INVARIANT_OFFSET = 0;
    uint256 private constant _LAST_POST_JOIN_EXIT_INVARIANT_SIZE = 233;
    uint256 private constant _LAST_JOIN_EXIT_AMPLIFICATION_OFFSET = _LAST_POST_JOIN_EXIT_INVARIANT_OFFSET +
        _LAST_POST_JOIN_EXIT_INVARIANT_SIZE;
    uint256 private constant _LAST_JOIN_EXIT_AMPLIFICATION_SIZE = 23;
    /**
     * @dev Calculates due protocol fees originating from accumulated swap fees and yield of non-exempt tokens, pays
     * them by minting BPT, and returns the actual supply and current balances.
     *
     * We also return the current invariant computed using the amplification factor at the last join or exit, which can
     * be useful to skip computations in scenarios where the amplification factor is not changing.
     */
    function _payProtocolFeesBeforeJoinExit(
        uint256[] memory registeredBalances,
        uint256 lastJoinExitAmp,
        uint256 lastPostJoinExitInvariant
    )
        internal
        returns (
            uint256,
            uint256[] memory,
            uint256
        )
    {
        (uint256 virtualSupply, uint256[] memory balances) = _dropBptItemFromBalances(registeredBalances);
        // First, we'll compute what percentage of the Pool the protocol should own due to charging protocol fees on
        // swap fees and yield.
        (
            uint256 expectedProtocolOwnershipPercentage,
            uint256 currentInvariantWithLastJoinExitAmp
        ) = _getProtocolPoolOwnershipPercentage(balances, lastJoinExitAmp, lastPostJoinExitInvariant);
        // Now that we know what percentage of the Pool's current value the protocol should own, we can compute how
        // much BPT we need to mint to get to this state. Since we're going to mint BPT for the protocol, the value
        // of each BPT is going to be reduced as all LPs get diluted.
        uint256 protocolFeeAmount = ProtocolFees.bptForPoolOwnershipPercentage(
            virtualSupply,
            expectedProtocolOwnershipPercentage
        );
        if (protocolFeeAmount > 0) {
            _payProtocolFees(protocolFeeAmount);
        }
        // We pay fees before a join or exit to ensure the pool is debt-free. This increases the virtual supply (making
        // it match the actual supply).
        //
        // For this addition to overflow, `totalSupply` would also have already overflowed.
        return (virtualSupply + protocolFeeAmount, balances, currentInvariantWithLastJoinExitAmp);
    }
    function _getProtocolPoolOwnershipPercentage(
        uint256[] memory balances,
        uint256 lastJoinExitAmp,
        uint256 lastPostJoinExitInvariant
    ) internal view returns (uint256, uint256) {
        // We compute three invariants, adjusting the balances of tokens that have rate providers by undoing the current
        // rate adjustment and then applying the old rate. This is equivalent to multiplying by old rate / current rate.
        //
        // In all cases we compute invariants with the last join-exit amplification factor, so that changes to the
        // amplification are not translated into changes to the invariant. Since amplification factor changes are both
        // infrequent and slow, they should have little effect on the pool balances, making this a very good
        // approximation.
        //
        // With this technique we obtain an invariant that does not include yield at all, meaning any growth will be due
        // exclusively to swap fees. We call this the 'swap fee growth invariant'.
        // A second invariant will exclude the yield of exempt tokens, and therefore include both swap fees and
        // non-exempt yield. This is called the 'non exempt growth invariant'.
        // Finally, a third invariant includes the yield of all tokens by using only the current rates. We call this the
        // 'total growth invariant', since it includes both swap fee growth, non-exempt yield growth and exempt yield
        // growth. If the last join-exit amplification equals the current one, this invariant equals the current
        // invariant.
        (
            uint256 swapFeeGrowthInvariant,
            uint256 totalNonExemptGrowthInvariant,
            uint256 totalGrowthInvariant
        ) = _getGrowthInvariants(balances, lastJoinExitAmp, lastPostJoinExitInvariant);
        // By comparing the invariant increase attributable to each source of growth to the total growth invariant,
        // we can calculate how much of the current Pool value originates from that source, and then apply the
        // corresponding protocol fee percentage to that amount.
        // We have two sources of growth: swap fees, and non-exempt yield. As we illustrate graphically below:
        //
        // growth due to swap fees        = (swap fee growth invariant - last post join-exit invariant)
        // growth due to non-exempt yield = (non-exempt growth invariant - swap fee growth invariant)
        //
        // These can be converted to additive percentages by normalizing against the total growth invariant value:
        // growth due to swap fees / total growth invariant = % pool ownership due from swap fees
        // growth due to non-exempt yield / total growth invariant = % pool ownership due from non-exempt yield
        //
        //   ┌───────────────────────┐ ──┐
        //   │  exempt yield         │   │  total growth invariant
        //   ├───────────────────────┤   │ ──┐
        //   │  non-exempt yield     │   │   │  non-exempt growth invariant
        //   ├───────────────────────┤   │   │ ──┐
        //   │  swap fees            │   │   │   │  swap fee growth invariant
        //   ├───────────────────────┤   │   │   │ ──┐
        //   │   original value      │   │   │   │   │  last post join-exit invariant
        //   └───────────────────────┘ ──┘ ──┘ ──┘ ──┘
        //
        // Each invariant should be larger than its precedessor. In case any rounding error results in them being
        // smaller, we adjust the subtraction to equal 0.
        // Note: in the unexpected scenario where the rates of the tokens shrink over time instead of growing (i.e. if
        // the yield is negative), the non-exempt growth invariant might actually be *smaller* than the swap fee growth
        // invariant, and the total growth invariant might be *smaller* than the non-exempt growth invariant. Depending
        // on the order in which swaps, joins/exits and rate changes happen, as well as their relative magnitudes, it is
        // possible for the Pool to either pay more or less protocol fees than it should.
        // This patched version handles these edge cases gracefully, as it 1) forcibly bounds the swap fee growth
        // invariant between the total growth and last post join-exit invariant; 2) enforces "all or nothing" exempt
        // flags, which constrains the non-exempt growth invariant to be equal to either the total growth or swap
        // fee growth invariant.
        //
        // Furthermore, the protocol ownership percentage is hard-coded to zero (so protocol fees will be zero),
        // if the total growth invariant has gone *down* since the last join or exit, which is possible if rates
        // declined. Together, these measures ensure protocol fee amounts will be bound by the non-manipulable
        // swap fee growth, or zero in any pathological situations.
        // If the total invariant decreased or stayed the same, there is no growth to split between swap and yield fees.
        if (totalGrowthInvariant <= lastPostJoinExitInvariant) {
            return (0, totalGrowthInvariant);
        }
        // By now, the following inequality applies:
        // totalGrowthInvariant >= totalNonExemptGrowthInvariant >= swapFeeGrowthInvariant >= lastPostJoinExitInvariant
        // So these differences are safe to execute; their lower bound is 0 and they will not overflow.
        uint256 swapFeeGrowthInvariantDelta = swapFeeGrowthInvariant - lastPostJoinExitInvariant;
        uint256 nonExemptYieldGrowthInvariantDelta = totalNonExemptGrowthInvariant - swapFeeGrowthInvariant;
        // We can now derive what percentage of the Pool's total value each invariant delta represents by dividing by
        // the total growth invariant. These values, multiplied by the protocol fee percentage for each growth type,
        // represent the percentage of Pool ownership the protocol should have due to each source.
        uint256 protocolSwapFeePercentage = swapFeeGrowthInvariantDelta.divDown(totalGrowthInvariant).mulDown(
            getProtocolFeePercentageCache(ProtocolFeeType.SWAP)
        );
        uint256 protocolYieldPercentage = nonExemptYieldGrowthInvariantDelta.divDown(totalGrowthInvariant).mulDown(
            getProtocolFeePercentageCache(ProtocolFeeType.YIELD)
        );
        // These percentages can then be simply added to compute the total protocol Pool ownership percentage.
        // This is naturally bounded above by FixedPoint.ONE so this addition cannot overflow.
        return (protocolSwapFeePercentage + protocolYieldPercentage, totalGrowthInvariant);
    }
    /**
     * @dev Returns total growth invariant and swap / yield invariant approximations.
     * The calculated invariants are bounded such that:
     *
     * - if totalGrowthInvariant <= lastPostJoinExitInvariant, the total value has decreased, so we can skip all
     * other invariant calculations and just return `totalGrowthInvariant` for all. Protocol fees should be zero
     * in this case, so callers using this to compute fees must also check for this, and return zero for the
     * protocol ownership percentage.
     *
     * - Otherwise, totalGrowthInvariant >= totalNonExemptGrowthInvariant >=
     *     swapFeeGrowthInvariant >= lastPostJoinExitInvariant
     * This was previously an assumption, but is now ensured by the logic in this function.
     */
    function _getGrowthInvariants(
        uint256[] memory balances,
        uint256 lastJoinExitAmp,
        uint256 lastPostJoinExitInvariant
    )
        internal
        view
        returns (
            uint256 swapFeeGrowthInvariant,
            uint256 totalNonExemptGrowthInvariant,
            uint256 totalGrowthInvariant
        )
    {
        // Total growth invariant is always calculated with the current (scaled / unadjusted) balances.
        totalGrowthInvariant = StableMath._calculateInvariant(lastJoinExitAmp, balances);
        // If total invariant decreased, calculating the other approximations is unnecessary.
        if (totalGrowthInvariant <= lastPostJoinExitInvariant) {
            return (totalGrowthInvariant, totalGrowthInvariant, totalGrowthInvariant);
        }
        // Swap fee invariant is calculated with adjusted balances, to discount the yield.
        swapFeeGrowthInvariant = StableMath._calculateInvariant(
            lastJoinExitAmp,
            _getAdjustedBalances(balances) // Adjust all token balances with rate providers.
        );
        // The `swapFeeGrowthInvariant` cannot ever be outside the bounds:
        // totalGrowthInvariant >= swapFeeGrowthInvariant >= lastPostJoinExitInvariant
        swapFeeGrowthInvariant = Math.min(totalGrowthInvariant, swapFeeGrowthInvariant); // Set upper bound.
        swapFeeGrowthInvariant = Math.max(lastPostJoinExitInvariant, swapFeeGrowthInvariant); // Set lower bound.
        // The only two accepted possibilities are either all tokens exempt, or none tokens exempt.
        // totalNonExemptGrowthInvariant will either be totalGrowthInvariant or swapFeeGrowthInvariant.
        // At this point,
        // - totalGrowthInvariant > lastPostJoinExitInvariant
        // - totalGrowthInvariant >= swapFeeGrowthInvariant >= lastPostJoinExitInvariant
        // So the complete inequality will apply by the end of this function:
        // totalGrowthInvariant >= totalNonExemptGrowthInvariant >= swapFeeGrowthInvariant >= lastPostJoinExitInvariant
        if (isExemptFromYieldProtocolFee()) {
            // If no tokens are charged fees on yield, then the non-exempt growth is equal to the swap fee growth - no
            // yield fees will be collected.
            totalNonExemptGrowthInvariant = swapFeeGrowthInvariant;
        } else {
            // If there are no tokens with fee-exempt yield, then the total non-exempt growth will equal the total
            // growth: all yield growth is non-exempt. There's also no point in adjusting balances, since we
            // already know none are exempt.
            totalNonExemptGrowthInvariant = totalGrowthInvariant;
        }
    }
    /**
     * @dev Store the latest invariant based on the adjusted balances after the join or exit, using current rates.
     * Also cache the amp factor, so that the invariant is not affected by amp updates between joins and exits.
     *
     * Pay protocol fees due on any current join or exit swap.
     */
    function _updateInvariantAfterJoinExit(
        uint256 currentAmp,
        uint256[] memory balances,
        uint256 preJoinExitInvariant,
        uint256 preJoinExitSupply,
        uint256 postJoinExitSupply
    ) internal {
        // `_payProtocolFeesBeforeJoinExit` paid protocol fees accumulated between the previous and current
        // join or exit, while this code pays any protocol fees due on the current join or exit.
        // The amp and rates are constant during a single transaction, so it doesn't matter if there
        // is an ongoing amp change, and we can ignore yield.
        // Compute the growth ratio between the pre- and post-join/exit balances.
        // Note that the pre-join/exit invariant is *not* the invariant from the last join,
        // but computed from the balances before this particular join/exit.
        uint256 postJoinExitInvariant = StableMath._calculateInvariant(currentAmp, balances);
        // Compute the portion of the invariant increase due to fees
        uint256 supplyGrowthRatio = postJoinExitSupply.divDown(preJoinExitSupply);
        uint256 feelessInvariant = preJoinExitInvariant.mulDown(supplyGrowthRatio);
        // The postJoinExitInvariant should always be greater than the feelessInvariant (since the invariant and total
        // supply move proportionally outside of fees, which the postJoinInvariant includes and the feelessInvariant
        // does not). However, in the unexpected case in which due to rounding errors this is not true, we simply skip
        // further computation of protocol fees.
        if (postJoinExitInvariant > feelessInvariant) {
            uint256 invariantDeltaFromFees = postJoinExitInvariant - feelessInvariant;
            // To convert to a percentage of pool ownership, multiply by the rate,
            // then normalize against the final invariant
            uint256 protocolOwnershipPercentage = Math.divDown(
                Math.mul(invariantDeltaFromFees, getProtocolFeePercentageCache(ProtocolFeeType.SWAP)),
                postJoinExitInvariant
            );
            if (protocolOwnershipPercentage > 0) {
                uint256 protocolFeeAmount = ProtocolFees.bptForPoolOwnershipPercentage(
                    postJoinExitSupply,
                    protocolOwnershipPercentage
                );
                _payProtocolFees(protocolFeeAmount);
            }
        }
        _updatePostJoinExit(currentAmp, postJoinExitInvariant);
    }
    /**
     * @dev Update the stored values of the amp and final post-join/exit invariant, to reset the basis for protocol
     * swap fees. Also copy the current rates to the old rates, to establish the new protocol yield basis for protocol
     * yield fees.
     */
    function _updatePostJoinExit(uint256 currentAmp, uint256 postJoinExitInvariant) internal {
        _lastJoinExitData =
            WordCodec.encodeUint(currentAmp, _LAST_JOIN_EXIT_AMPLIFICATION_OFFSET, _LAST_JOIN_EXIT_AMPLIFICATION_SIZE) |
            WordCodec.encodeUint(
                postJoinExitInvariant,
                _LAST_POST_JOIN_EXIT_INVARIANT_OFFSET,
                _LAST_POST_JOIN_EXIT_INVARIANT_SIZE
            );
        _updateOldRates();
    }
    /**
     * @notice Return the amplification factor and invariant as of the most recent join or exit (including BPT swaps)
     */
    function getLastJoinExitData()
        public
        view
        returns (uint256 lastJoinExitAmplification, uint256 lastPostJoinExitInvariant)
    {
        bytes32 rawData = _lastJoinExitData;
        lastJoinExitAmplification = rawData.decodeUint(
            _LAST_JOIN_EXIT_AMPLIFICATION_OFFSET,
            _LAST_JOIN_EXIT_AMPLIFICATION_SIZE
        );
        lastPostJoinExitInvariant = rawData.decodeUint(
            _LAST_POST_JOIN_EXIT_INVARIANT_OFFSET,
            _LAST_POST_JOIN_EXIT_INVARIANT_SIZE
        );
    }
    /**
     * @dev Inheritance rules still require us to override this in the most derived contract, even though
     * it only calls super.
     */
    function _isOwnerOnlyAction(bytes32 actionId)
        internal
        view
        virtual
        override(
            // Our inheritance pattern creates a small diamond that requires explicitly listing the parents here.
            // Each parent calls the `super` version, so linearization ensures all implementations are called.
            BasePool,
            BasePoolAuthorization,
            ComposableStablePoolRates
        )
        returns (bool)
    {
        return super._isOwnerOnlyAction(actionId);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-pool-utils/contracts/BasePoolAuthorization.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
import "./StableMath.sol";
abstract contract StablePoolAmplification is BasePoolAuthorization {
    using WordCodec for bytes32;
    // This contract uses timestamps to slowly update its Amplification parameter over time. These changes must occur
    // over a minimum time period much larger than the blocktime, making timestamp manipulation a non-issue.
    // solhint-disable not-rely-on-time
    // Amplification factor changes must happen over a minimum period of one day, and can at most divide or multiply the
    // current value by 2 every day.
    // WARNING: this only limits *a single* amplification change to have a maximum rate of change of twice the original
    // value daily. It is possible to perform multiple amplification changes in sequence to increase this value more
    // rapidly: for example, by doubling the value every day it can increase by a factor of 8 over three days (2^3).
    uint256 private constant _MIN_UPDATE_TIME = 1 days;
    uint256 private constant _MAX_AMP_UPDATE_DAILY_RATE = 2;
    // The amplification data structure is as follows:
    // [  64 bits |   64 bits  |  64 bits  |   64 bits   ]
    // [ end time | start time | end value | start value ]
    // |MSB                                           LSB|
    uint256 private constant _AMP_START_VALUE_OFFSET = 0;
    uint256 private constant _AMP_END_VALUE_OFFSET = 64;
    uint256 private constant _AMP_START_TIME_OFFSET = 128;
    uint256 private constant _AMP_END_TIME_OFFSET = 192;
    uint256 private constant _AMP_VALUE_BIT_LENGTH = 64;
    uint256 private constant _AMP_TIMESTAMP_BIT_LENGTH = 64;
    bytes32 private _packedAmplificationData;
    event AmpUpdateStarted(uint256 startValue, uint256 endValue, uint256 startTime, uint256 endTime);
    event AmpUpdateStopped(uint256 currentValue);
    constructor(uint256 amplificationParameter) {
        _require(amplificationParameter >= StableMath._MIN_AMP, Errors.MIN_AMP);
        _require(amplificationParameter <= StableMath._MAX_AMP, Errors.MAX_AMP);
        uint256 initialAmp = Math.mul(amplificationParameter, StableMath._AMP_PRECISION);
        _setAmplificationData(initialAmp);
    }
    function getAmplificationParameter()
        external
        view
        returns (
            uint256 value,
            bool isUpdating,
            uint256 precision
        )
    {
        (value, isUpdating) = _getAmplificationParameter();
        precision = StableMath._AMP_PRECISION;
    }
    // Return the current amp value, which will be an interpolation if there is an ongoing amp update.
    // Also return a flag indicating whether there is an ongoing update.
    function _getAmplificationParameter() internal view returns (uint256 value, bool isUpdating) {
        (uint256 startValue, uint256 endValue, uint256 startTime, uint256 endTime) = _getAmplificationData();
        // Note that block.timestamp >= startTime, since startTime is set to the current time when an update starts
        if (block.timestamp < endTime) {
            isUpdating = true;
            // We can skip checked arithmetic as:
            //  - block.timestamp is always larger or equal to startTime
            //  - endTime is always larger than startTime
            //  - the value delta is bounded by the largest amplification parameter, which never causes the
            //    multiplication to overflow.
            // This also means that the following computation will never revert nor yield invalid results.
            if (endValue > startValue) {
                value = startValue + ((endValue - startValue) * (block.timestamp - startTime)) / (endTime - startTime);
            } else {
                value = startValue - ((startValue - endValue) * (block.timestamp - startTime)) / (endTime - startTime);
            }
        } else {
            isUpdating = false;
            value = endValue;
        }
    }
    // Unpack and return all amplification-related parameters.
    function _getAmplificationData()
        private
        view
        returns (
            uint256 startValue,
            uint256 endValue,
            uint256 startTime,
            uint256 endTime
        )
    {
        startValue = _packedAmplificationData.decodeUint(_AMP_START_VALUE_OFFSET, _AMP_VALUE_BIT_LENGTH);
        endValue = _packedAmplificationData.decodeUint(_AMP_END_VALUE_OFFSET, _AMP_VALUE_BIT_LENGTH);
        startTime = _packedAmplificationData.decodeUint(_AMP_START_TIME_OFFSET, _AMP_TIMESTAMP_BIT_LENGTH);
        endTime = _packedAmplificationData.decodeUint(_AMP_END_TIME_OFFSET, _AMP_TIMESTAMP_BIT_LENGTH);
    }
    /**
     * @dev Begin changing the amplification parameter to `rawEndValue` over time. The value will change linearly until
     * `endTime` is reached, when it will be `rawEndValue`.
     *
     * NOTE: Internally, the amplification parameter is represented using higher precision. The values returned by
     * `getAmplificationParameter` have to be corrected to account for this when comparing to `rawEndValue`.
     */
    function startAmplificationParameterUpdate(uint256 rawEndValue, uint256 endTime) external authenticate {
        _require(rawEndValue >= StableMath._MIN_AMP, Errors.MIN_AMP);
        _require(rawEndValue <= StableMath._MAX_AMP, Errors.MAX_AMP);
        uint256 duration = Math.sub(endTime, block.timestamp);
        _require(duration >= _MIN_UPDATE_TIME, Errors.AMP_END_TIME_TOO_CLOSE);
        (uint256 currentValue, bool isUpdating) = _getAmplificationParameter();
        _require(!isUpdating, Errors.AMP_ONGOING_UPDATE);
        uint256 endValue = Math.mul(rawEndValue, StableMath._AMP_PRECISION);
        // daily rate = (endValue / currentValue) / duration * 1 day
        // We perform all multiplications first to not reduce precision, and round the division up as we want to avoid
        // large rates. Note that these are regular integer multiplications and divisions, not fixed point.
        uint256 dailyRate = endValue > currentValue
            ? Math.divUp(Math.mul(1 days, endValue), Math.mul(currentValue, duration))
            : Math.divUp(Math.mul(1 days, currentValue), Math.mul(endValue, duration));
        _require(dailyRate <= _MAX_AMP_UPDATE_DAILY_RATE, Errors.AMP_RATE_TOO_HIGH);
        _setAmplificationData(currentValue, endValue, block.timestamp, endTime);
    }
    /**
     * @dev Stops the amplification parameter change process, keeping the current value.
     */
    function stopAmplificationParameterUpdate() external authenticate {
        (uint256 currentValue, bool isUpdating) = _getAmplificationParameter();
        _require(isUpdating, Errors.AMP_NO_ONGOING_UPDATE);
        _setAmplificationData(currentValue);
    }
    function _setAmplificationData(uint256 value) private {
        _storeAmplificationData(value, value, block.timestamp, block.timestamp);
        emit AmpUpdateStopped(value);
    }
    function _setAmplificationData(
        uint256 startValue,
        uint256 endValue,
        uint256 startTime,
        uint256 endTime
    ) private {
        _storeAmplificationData(startValue, endValue, startTime, endTime);
        emit AmpUpdateStarted(startValue, endValue, startTime, endTime);
    }
    function _storeAmplificationData(
        uint256 startValue,
        uint256 endValue,
        uint256 startTime,
        uint256 endTime
    ) private {
        _packedAmplificationData =
            WordCodec.encodeUint(startValue, _AMP_START_VALUE_OFFSET, _AMP_VALUE_BIT_LENGTH) |
            WordCodec.encodeUint(endValue, _AMP_END_VALUE_OFFSET, _AMP_VALUE_BIT_LENGTH) |
            WordCodec.encodeUint(startTime, _AMP_START_TIME_OFFSET, _AMP_TIMESTAMP_BIT_LENGTH) |
            WordCodec.encodeUint(endTime, _AMP_END_TIME_OFFSET, _AMP_TIMESTAMP_BIT_LENGTH);
    }
    // Permissioned functions
    /**
     * @dev Overrides only owner action to allow setting the cache duration for the token rates
     */
    function _isOwnerOnlyAction(bytes32 actionId) internal view virtual override returns (bool) {
        return
            (actionId == getActionId(this.startAmplificationParameterUpdate.selector)) ||
            (actionId == getActionId(this.stopAmplificationParameterUpdate.selector)) ||
            super._isOwnerOnlyAction(actionId);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
// These functions start with an underscore, as if they were part of a contract and not a library. At some point this
// should be fixed. Additionally, some variables have non mixed case names (e.g. P_D) that relate to the mathematical
// derivations.
// solhint-disable private-vars-leading-underscore, var-name-mixedcase
library StableMath {
    using FixedPoint for uint256;
    uint256 internal constant _MIN_AMP = 1;
    uint256 internal constant _MAX_AMP = 5000;
    uint256 internal constant _AMP_PRECISION = 1e3;
    uint256 internal constant _MAX_STABLE_TOKENS = 5;
    // Note on unchecked arithmetic:
    // This contract performs a large number of additions, subtractions, multiplications and divisions, often inside
    // loops. Since many of these operations are gas-sensitive (as they happen e.g. during a swap), it is important to
    // not make any unnecessary checks. We rely on a set of invariants to avoid having to use checked arithmetic (the
    // Math library), including:
    //  - the number of tokens is bounded by _MAX_STABLE_TOKENS
    //  - the amplification parameter is bounded by _MAX_AMP * _AMP_PRECISION, which fits in 23 bits
    //  - the token balances are bounded by 2^112 (guaranteed by the Vault) times 1e18 (the maximum scaling factor),
    //    which fits in 172 bits
    //
    // This means e.g. we can safely multiply a balance by the amplification parameter without worrying about overflow.
    // About swap fees on joins and exits:
    // Any join or exit that is not perfectly balanced (e.g. all single token joins or exits) is mathematically
    // equivalent to a perfectly balanced join or  exit followed by a series of swaps. Since these swaps would charge
    // swap fees, it follows that (some) joins and exits should as well.
    // On these operations, we split the token amounts in 'taxable' and 'non-taxable' portions, where the 'taxable' part
    // is the one to which swap fees are applied.
    // Computes the invariant given the current balances, using the Newton-Raphson approximation.
    // The amplification parameter equals: A n^(n-1)
    // See: https://github.com/curvefi/curve-contract/blob/b0bbf77f8f93c9c5f4e415bce9cd71f0cdee960e/contracts/pool-templates/base/SwapTemplateBase.vy#L206
    // solhint-disable-previous-line max-line-length
    function _calculateInvariant(uint256 amplificationParameter, uint256[] memory balances)
        internal
        pure
        returns (uint256)
    {
        /**********************************************************************************************
        // invariant                                                                                 //
        // D = invariant                                                  D^(n+1)                    //
        // A = amplification coefficient      A  n^n S + D = A D n^n + -----------                   //
        // S = sum of balances                                             n^n P                     //
        // P = product of balances                                                                   //
        // n = number of tokens                                                                      //
        **********************************************************************************************/
        // Always round down, to match Vyper's arithmetic (which always truncates).
        uint256 sum = 0; // S in the Curve version
        uint256 numTokens = balances.length;
        for (uint256 i = 0; i < numTokens; i++) {
            sum = sum.add(balances[i]);
        }
        if (sum == 0) {
            return 0;
        }
        uint256 prevInvariant; // Dprev in the Curve version
        uint256 invariant = sum; // D in the Curve version
        uint256 ampTimesTotal = amplificationParameter * numTokens; // Ann in the Curve version
        for (uint256 i = 0; i < 255; i++) {
            uint256 D_P = invariant;
            for (uint256 j = 0; j < numTokens; j++) {
                // (D_P * invariant) / (balances[j] * numTokens)
                D_P = Math.divDown(Math.mul(D_P, invariant), Math.mul(balances[j], numTokens));
            }
            prevInvariant = invariant;
            invariant = Math.divDown(
                Math.mul(
                    // (ampTimesTotal * sum) / AMP_PRECISION + D_P * numTokens
                    (Math.divDown(Math.mul(ampTimesTotal, sum), _AMP_PRECISION).add(Math.mul(D_P, numTokens))),
                    invariant
                ),
                // ((ampTimesTotal - _AMP_PRECISION) * invariant) / _AMP_PRECISION + (numTokens + 1) * D_P
                (
                    Math.divDown(Math.mul((ampTimesTotal - _AMP_PRECISION), invariant), _AMP_PRECISION).add(
                        Math.mul((numTokens + 1), D_P)
                    )
                )
            );
            if (invariant > prevInvariant) {
                if (invariant - prevInvariant <= 1) {
                    return invariant;
                }
            } else if (prevInvariant - invariant <= 1) {
                return invariant;
            }
        }
        _revert(Errors.STABLE_INVARIANT_DIDNT_CONVERGE);
    }
    // Computes how many tokens can be taken out of a pool if `tokenAmountIn` are sent, given the current balances.
    // The amplification parameter equals: A n^(n-1)
    function _calcOutGivenIn(
        uint256 amplificationParameter,
        uint256[] memory balances,
        uint256 tokenIndexIn,
        uint256 tokenIndexOut,
        uint256 tokenAmountIn,
        uint256 invariant
    ) internal pure returns (uint256) {
        /**************************************************************************************************************
        // outGivenIn token x for y - polynomial equation to solve                                                   //
        // ay = amount out to calculate                                                                              //
        // by = balance token out                                                                                    //
        // y = by - ay (finalBalanceOut)                                                                             //
        // D = invariant                                               D                     D^(n+1)                 //
        // A = amplification coefficient               y^2 + ( S - ----------  - D) * y -  ------------- = 0         //
        // n = number of tokens                                    (A * n^n)               A * n^2n * P              //
        // S = sum of final balances but y                                                                           //
        // P = product of final balances but y                                                                       //
        **************************************************************************************************************/
        // Amount out, so we round down overall.
        balances[tokenIndexIn] = balances[tokenIndexIn].add(tokenAmountIn);
        uint256 finalBalanceOut = _getTokenBalanceGivenInvariantAndAllOtherBalances(
            amplificationParameter,
            balances,
            invariant,
            tokenIndexOut
        );
        // No need to use checked arithmetic since `tokenAmountIn` was actually added to the same balance right before
        // calling `_getTokenBalanceGivenInvariantAndAllOtherBalances` which doesn't alter the balances array.
        balances[tokenIndexIn] = balances[tokenIndexIn] - tokenAmountIn;
        return balances[tokenIndexOut].sub(finalBalanceOut).sub(1);
    }
    // Computes how many tokens must be sent to a pool if `tokenAmountOut` are sent given the
    // current balances, using the Newton-Raphson approximation.
    // The amplification parameter equals: A n^(n-1)
    function _calcInGivenOut(
        uint256 amplificationParameter,
        uint256[] memory balances,
        uint256 tokenIndexIn,
        uint256 tokenIndexOut,
        uint256 tokenAmountOut,
        uint256 invariant
    ) internal pure returns (uint256) {
        /**************************************************************************************************************
        // inGivenOut token x for y - polynomial equation to solve                                                   //
        // ax = amount in to calculate                                                                               //
        // bx = balance token in                                                                                     //
        // x = bx + ax (finalBalanceIn)                                                                              //
        // D = invariant                                                D                     D^(n+1)                //
        // A = amplification coefficient               x^2 + ( S - ----------  - D) * x -  ------------- = 0         //
        // n = number of tokens                                     (A * n^n)               A * n^2n * P             //
        // S = sum of final balances but x                                                                           //
        // P = product of final balances but x                                                                       //
        **************************************************************************************************************/
        // Amount in, so we round up overall.
        balances[tokenIndexOut] = balances[tokenIndexOut].sub(tokenAmountOut);
        uint256 finalBalanceIn = _getTokenBalanceGivenInvariantAndAllOtherBalances(
            amplificationParameter,
            balances,
            invariant,
            tokenIndexIn
        );
        // No need to use checked arithmetic since `tokenAmountOut` was actually subtracted from the same balance right
        // before calling `_getTokenBalanceGivenInvariantAndAllOtherBalances` which doesn't alter the balances array.
        balances[tokenIndexOut] = balances[tokenIndexOut] + tokenAmountOut;
        return finalBalanceIn.sub(balances[tokenIndexIn]).add(1);
    }
    function _calcBptOutGivenExactTokensIn(
        uint256 amp,
        uint256[] memory balances,
        uint256[] memory amountsIn,
        uint256 bptTotalSupply,
        uint256 currentInvariant,
        uint256 swapFeePercentage
    ) internal pure returns (uint256) {
        // BPT out, so we round down overall.
        // First loop calculates the sum of all token balances, which will be used to calculate
        // the current weights of each token, relative to this sum
        uint256 sumBalances = 0;
        for (uint256 i = 0; i < balances.length; i++) {
            sumBalances = sumBalances.add(balances[i]);
        }
        // Calculate the weighted balance ratio without considering fees
        uint256[] memory balanceRatiosWithFee = new uint256[](amountsIn.length);
        // The weighted sum of token balance ratios with fee
        uint256 invariantRatioWithFees = 0;
        for (uint256 i = 0; i < balances.length; i++) {
            uint256 currentWeight = balances[i].divDown(sumBalances);
            balanceRatiosWithFee[i] = balances[i].add(amountsIn[i]).divDown(balances[i]);
            invariantRatioWithFees = invariantRatioWithFees.add(balanceRatiosWithFee[i].mulDown(currentWeight));
        }
        // Second loop calculates new amounts in, taking into account the fee on the percentage excess
        uint256[] memory newBalances = new uint256[](balances.length);
        for (uint256 i = 0; i < balances.length; i++) {
            uint256 amountInWithoutFee;
            // Check if the balance ratio is greater than the ideal ratio to charge fees or not
            if (balanceRatiosWithFee[i] > invariantRatioWithFees) {
                uint256 nonTaxableAmount = balances[i].mulDown(invariantRatioWithFees.sub(FixedPoint.ONE));
                uint256 taxableAmount = amountsIn[i].sub(nonTaxableAmount);
                // No need to use checked arithmetic for the swap fee, it is guaranteed to be lower than 50%
                amountInWithoutFee = nonTaxableAmount.add(taxableAmount.mulDown(FixedPoint.ONE - swapFeePercentage));
            } else {
                amountInWithoutFee = amountsIn[i];
            }
            newBalances[i] = balances[i].add(amountInWithoutFee);
        }
        uint256 newInvariant = _calculateInvariant(amp, newBalances);
        uint256 invariantRatio = newInvariant.divDown(currentInvariant);
        // If the invariant didn't increase for any reason, we simply don't mint BPT
        if (invariantRatio > FixedPoint.ONE) {
            return bptTotalSupply.mulDown(invariantRatio - FixedPoint.ONE);
        } else {
            return 0;
        }
    }
    function _calcTokenInGivenExactBptOut(
        uint256 amp,
        uint256[] memory balances,
        uint256 tokenIndex,
        uint256 bptAmountOut,
        uint256 bptTotalSupply,
        uint256 currentInvariant,
        uint256 swapFeePercentage
    ) internal pure returns (uint256) {
        // Token in, so we round up overall.
        uint256 newInvariant = bptTotalSupply.add(bptAmountOut).divUp(bptTotalSupply).mulUp(currentInvariant);
        // Calculate amount in without fee.
        uint256 newBalanceTokenIndex = _getTokenBalanceGivenInvariantAndAllOtherBalances(
            amp,
            balances,
            newInvariant,
            tokenIndex
        );
        uint256 amountInWithoutFee = newBalanceTokenIndex.sub(balances[tokenIndex]);
        // First calculate the sum of all token balances, which will be used to calculate
        // the current weight of each token
        uint256 sumBalances = 0;
        for (uint256 i = 0; i < balances.length; i++) {
            sumBalances = sumBalances.add(balances[i]);
        }
        // We can now compute how much extra balance is being deposited and used in virtual swaps, and charge swap fees
        // accordingly.
        uint256 currentWeight = balances[tokenIndex].divDown(sumBalances);
        uint256 taxablePercentage = currentWeight.complement();
        uint256 taxableAmount = amountInWithoutFee.mulUp(taxablePercentage);
        uint256 nonTaxableAmount = amountInWithoutFee.sub(taxableAmount);
        // No need to use checked arithmetic for the swap fee, it is guaranteed to be lower than 50%
        return nonTaxableAmount.add(taxableAmount.divUp(FixedPoint.ONE - swapFeePercentage));
    }
    /*
    Flow of calculations:
    amountsTokenOut -> amountsOutProportional ->
    amountOutPercentageExcess -> amountOutBeforeFee -> newInvariant -> amountBPTIn
    */
    function _calcBptInGivenExactTokensOut(
        uint256 amp,
        uint256[] memory balances,
        uint256[] memory amountsOut,
        uint256 bptTotalSupply,
        uint256 currentInvariant,
        uint256 swapFeePercentage
    ) internal pure returns (uint256) {
        // BPT in, so we round up overall.
        // First loop calculates the sum of all token balances, which will be used to calculate
        // the current weights of each token relative to this sum
        uint256 sumBalances = 0;
        for (uint256 i = 0; i < balances.length; i++) {
            sumBalances = sumBalances.add(balances[i]);
        }
        // Calculate the weighted balance ratio without considering fees
        uint256[] memory balanceRatiosWithoutFee = new uint256[](amountsOut.length);
        uint256 invariantRatioWithoutFees = 0;
        for (uint256 i = 0; i < balances.length; i++) {
            uint256 currentWeight = balances[i].divUp(sumBalances);
            balanceRatiosWithoutFee[i] = balances[i].sub(amountsOut[i]).divUp(balances[i]);
            invariantRatioWithoutFees = invariantRatioWithoutFees.add(balanceRatiosWithoutFee[i].mulUp(currentWeight));
        }
        // Second loop calculates new amounts in, taking into account the fee on the percentage excess
        uint256[] memory newBalances = new uint256[](balances.length);
        for (uint256 i = 0; i < balances.length; i++) {
            // Swap fees are typically charged on 'token in', but there is no 'token in' here, so we apply it to
            // 'token out'. This results in slightly larger price impact.
            uint256 amountOutWithFee;
            if (invariantRatioWithoutFees > balanceRatiosWithoutFee[i]) {
                uint256 nonTaxableAmount = balances[i].mulDown(invariantRatioWithoutFees.complement());
                uint256 taxableAmount = amountsOut[i].sub(nonTaxableAmount);
                // No need to use checked arithmetic for the swap fee, it is guaranteed to be lower than 50%
                amountOutWithFee = nonTaxableAmount.add(taxableAmount.divUp(FixedPoint.ONE - swapFeePercentage));
            } else {
                amountOutWithFee = amountsOut[i];
            }
            newBalances[i] = balances[i].sub(amountOutWithFee);
        }
        uint256 newInvariant = _calculateInvariant(amp, newBalances);
        uint256 invariantRatio = newInvariant.divDown(currentInvariant);
        // return amountBPTIn
        return bptTotalSupply.mulUp(invariantRatio.complement());
    }
    function _calcTokenOutGivenExactBptIn(
        uint256 amp,
        uint256[] memory balances,
        uint256 tokenIndex,
        uint256 bptAmountIn,
        uint256 bptTotalSupply,
        uint256 currentInvariant,
        uint256 swapFeePercentage
    ) internal pure returns (uint256) {
        // Token out, so we round down overall.
        uint256 newInvariant = bptTotalSupply.sub(bptAmountIn).divUp(bptTotalSupply).mulUp(currentInvariant);
        // Calculate amount out without fee
        uint256 newBalanceTokenIndex = _getTokenBalanceGivenInvariantAndAllOtherBalances(
            amp,
            balances,
            newInvariant,
            tokenIndex
        );
        uint256 amountOutWithoutFee = balances[tokenIndex].sub(newBalanceTokenIndex);
        // First calculate the sum of all token balances, which will be used to calculate
        // the current weight of each token
        uint256 sumBalances = 0;
        for (uint256 i = 0; i < balances.length; i++) {
            sumBalances = sumBalances.add(balances[i]);
        }
        // We can now compute how much excess balance is being withdrawn as a result of the virtual swaps, which result
        // in swap fees.
        uint256 currentWeight = balances[tokenIndex].divDown(sumBalances);
        uint256 taxablePercentage = currentWeight.complement();
        // Swap fees are typically charged on 'token in', but there is no 'token in' here, so we apply it
        // to 'token out'. This results in slightly larger price impact. Fees are rounded up.
        uint256 taxableAmount = amountOutWithoutFee.mulUp(taxablePercentage);
        uint256 nonTaxableAmount = amountOutWithoutFee.sub(taxableAmount);
        // No need to use checked arithmetic for the swap fee, it is guaranteed to be lower than 50%
        return nonTaxableAmount.add(taxableAmount.mulDown(FixedPoint.ONE - swapFeePercentage));
    }
    // This function calculates the balance of a given token (tokenIndex)
    // given all the other balances and the invariant
    function _getTokenBalanceGivenInvariantAndAllOtherBalances(
        uint256 amplificationParameter,
        uint256[] memory balances,
        uint256 invariant,
        uint256 tokenIndex
    ) internal pure returns (uint256) {
        // Rounds result up overall
        uint256 ampTimesTotal = amplificationParameter * balances.length;
        uint256 sum = balances[0];
        uint256 P_D = balances[0] * balances.length;
        for (uint256 j = 1; j < balances.length; j++) {
            P_D = Math.divDown(Math.mul(Math.mul(P_D, balances[j]), balances.length), invariant);
            sum = sum.add(balances[j]);
        }
        // No need to use safe math, based on the loop above `sum` is greater than or equal to `balances[tokenIndex]`
        sum = sum - balances[tokenIndex];
        uint256 inv2 = Math.mul(invariant, invariant);
        // We remove the balance from c by multiplying it
        uint256 c = Math.mul(
            Math.mul(Math.divUp(inv2, Math.mul(ampTimesTotal, P_D)), _AMP_PRECISION),
            balances[tokenIndex]
        );
        uint256 b = sum.add(Math.mul(Math.divDown(invariant, ampTimesTotal), _AMP_PRECISION));
        // We iterate to find the balance
        uint256 prevTokenBalance = 0;
        // We multiply the first iteration outside the loop with the invariant to set the value of the
        // initial approximation.
        uint256 tokenBalance = Math.divUp(inv2.add(c), invariant.add(b));
        for (uint256 i = 0; i < 255; i++) {
            prevTokenBalance = tokenBalance;
            tokenBalance = Math.divUp(
                Math.mul(tokenBalance, tokenBalance).add(c),
                Math.mul(tokenBalance, 2).add(b).sub(invariant)
            );
            if (tokenBalance > prevTokenBalance) {
                if (tokenBalance - prevTokenBalance <= 1) {
                    return tokenBalance;
                }
            } else if (prevTokenBalance - tokenBalance <= 1) {
                return tokenBalance;
            }
        }
        _revert(Errors.STABLE_GET_BALANCE_DIDNT_CONVERGE);
    }
    function _computeProportionalAmountsIn(
        uint256[] memory balances,
        uint256 bptAmountOut,
        uint256 totalBPT
    ) internal pure returns (uint256[] memory) {
        /************************************************************************************
        // tokensInForExactBptOut                                                          //
        // (per token)                                                                     //
        // aI = amountIn                   /   bptOut   \\                                  //
        // b = balance           aI = b * | ------------ |                                 //
        // bptOut = bptAmountOut           \\  totalBPT  /                                  //
        // bpt = totalBPT                                                                  //
        ************************************************************************************/
        // Tokens in, so we round up overall.
        uint256 bptRatio = bptAmountOut.divUp(totalBPT);
        uint256[] memory amountsIn = new uint256[](balances.length);
        for (uint256 i = 0; i < balances.length; i++) {
            amountsIn[i] = balances[i].mulUp(bptRatio);
        }
        return amountsIn;
    }
}
// SPDX-License-Identifier: MIT
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
// documentation files (the “Software”), to deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
// Software.
// THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
// WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
/* solhint-disable */
/**
 * @dev Exponentiation and logarithm functions for 18 decimal fixed point numbers (both base and exponent/argument).
 *
 * Exponentiation and logarithm with arbitrary bases (x^y and log_x(y)) are implemented by conversion to natural
 * exponentiation and logarithm (where the base is Euler's number).
 *
 * @author Fernando Martinelli - @fernandomartinelli
 * @author Sergio Yuhjtman - @sergioyuhjtman
 * @author Daniel Fernandez - @dmf7z
 */
library LogExpMath {
    // All fixed point multiplications and divisions are inlined. This means we need to divide by ONE when multiplying
    // two numbers, and multiply by ONE when dividing them.
    // All arguments and return values are 18 decimal fixed point numbers.
    int256 constant ONE_18 = 1e18;
    // Internally, intermediate values are computed with higher precision as 20 decimal fixed point numbers, and in the
    // case of ln36, 36 decimals.
    int256 constant ONE_20 = 1e20;
    int256 constant ONE_36 = 1e36;
    // The domain of natural exponentiation is bound by the word size and number of decimals used.
    //
    // Because internally the result will be stored using 20 decimals, the largest possible result is
    // (2^255 - 1) / 10^20, which makes the largest exponent ln((2^255 - 1) / 10^20) = 130.700829182905140221.
    // The smallest possible result is 10^(-18), which makes largest negative argument
    // ln(10^(-18)) = -41.446531673892822312.
    // We use 130.0 and -41.0 to have some safety margin.
    int256 constant MAX_NATURAL_EXPONENT = 130e18;
    int256 constant MIN_NATURAL_EXPONENT = -41e18;
    // Bounds for ln_36's argument. Both ln(0.9) and ln(1.1) can be represented with 36 decimal places in a fixed point
    // 256 bit integer.
    int256 constant LN_36_LOWER_BOUND = ONE_18 - 1e17;
    int256 constant LN_36_UPPER_BOUND = ONE_18 + 1e17;
    uint256 constant MILD_EXPONENT_BOUND = 2**254 / uint256(ONE_20);
    // 18 decimal constants
    int256 constant x0 = 128000000000000000000; // 2ˆ7
    int256 constant a0 = 38877084059945950922200000000000000000000000000000000000; // eˆ(x0) (no decimals)
    int256 constant x1 = 64000000000000000000; // 2ˆ6
    int256 constant a1 = 6235149080811616882910000000; // eˆ(x1) (no decimals)
    // 20 decimal constants
    int256 constant x2 = 3200000000000000000000; // 2ˆ5
    int256 constant a2 = 7896296018268069516100000000000000; // eˆ(x2)
    int256 constant x3 = 1600000000000000000000; // 2ˆ4
    int256 constant a3 = 888611052050787263676000000; // eˆ(x3)
    int256 constant x4 = 800000000000000000000; // 2ˆ3
    int256 constant a4 = 298095798704172827474000; // eˆ(x4)
    int256 constant x5 = 400000000000000000000; // 2ˆ2
    int256 constant a5 = 5459815003314423907810; // eˆ(x5)
    int256 constant x6 = 200000000000000000000; // 2ˆ1
    int256 constant a6 = 738905609893065022723; // eˆ(x6)
    int256 constant x7 = 100000000000000000000; // 2ˆ0
    int256 constant a7 = 271828182845904523536; // eˆ(x7)
    int256 constant x8 = 50000000000000000000; // 2ˆ-1
    int256 constant a8 = 164872127070012814685; // eˆ(x8)
    int256 constant x9 = 25000000000000000000; // 2ˆ-2
    int256 constant a9 = 128402541668774148407; // eˆ(x9)
    int256 constant x10 = 12500000000000000000; // 2ˆ-3
    int256 constant a10 = 113314845306682631683; // eˆ(x10)
    int256 constant x11 = 6250000000000000000; // 2ˆ-4
    int256 constant a11 = 106449445891785942956; // eˆ(x11)
    /**
     * @dev Exponentiation (x^y) with unsigned 18 decimal fixed point base and exponent.
     *
     * Reverts if ln(x) * y is smaller than `MIN_NATURAL_EXPONENT`, or larger than `MAX_NATURAL_EXPONENT`.
     */
    function pow(uint256 x, uint256 y) internal pure returns (uint256) {
        if (y == 0) {
            // We solve the 0^0 indetermination by making it equal one.
            return uint256(ONE_18);
        }
        if (x == 0) {
            return 0;
        }
        // Instead of computing x^y directly, we instead rely on the properties of logarithms and exponentiation to
        // arrive at that result. In particular, exp(ln(x)) = x, and ln(x^y) = y * ln(x). This means
        // x^y = exp(y * ln(x)).
        // The ln function takes a signed value, so we need to make sure x fits in the signed 256 bit range.
        _require(x >> 255 == 0, Errors.X_OUT_OF_BOUNDS);
        int256 x_int256 = int256(x);
        // We will compute y * ln(x) in a single step. Depending on the value of x, we can either use ln or ln_36. In
        // both cases, we leave the division by ONE_18 (due to fixed point multiplication) to the end.
        // This prevents y * ln(x) from overflowing, and at the same time guarantees y fits in the signed 256 bit range.
        _require(y < MILD_EXPONENT_BOUND, Errors.Y_OUT_OF_BOUNDS);
        int256 y_int256 = int256(y);
        int256 logx_times_y;
        if (LN_36_LOWER_BOUND < x_int256 && x_int256 < LN_36_UPPER_BOUND) {
            int256 ln_36_x = _ln_36(x_int256);
            // ln_36_x has 36 decimal places, so multiplying by y_int256 isn't as straightforward, since we can't just
            // bring y_int256 to 36 decimal places, as it might overflow. Instead, we perform two 18 decimal
            // multiplications and add the results: one with the first 18 decimals of ln_36_x, and one with the
            // (downscaled) last 18 decimals.
            logx_times_y = ((ln_36_x / ONE_18) * y_int256 + ((ln_36_x % ONE_18) * y_int256) / ONE_18);
        } else {
            logx_times_y = _ln(x_int256) * y_int256;
        }
        logx_times_y /= ONE_18;
        // Finally, we compute exp(y * ln(x)) to arrive at x^y
        _require(
            MIN_NATURAL_EXPONENT <= logx_times_y && logx_times_y <= MAX_NATURAL_EXPONENT,
            Errors.PRODUCT_OUT_OF_BOUNDS
        );
        return uint256(exp(logx_times_y));
    }
    /**
     * @dev Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
     *
     * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
     */
    function exp(int256 x) internal pure returns (int256) {
        _require(x >= MIN_NATURAL_EXPONENT && x <= MAX_NATURAL_EXPONENT, Errors.INVALID_EXPONENT);
        if (x < 0) {
            // We only handle positive exponents: e^(-x) is computed as 1 / e^x. We can safely make x positive since it
            // fits in the signed 256 bit range (as it is larger than MIN_NATURAL_EXPONENT).
            // Fixed point division requires multiplying by ONE_18.
            return ((ONE_18 * ONE_18) / exp(-x));
        }
        // First, we use the fact that e^(x+y) = e^x * e^y to decompose x into a sum of powers of two, which we call x_n,
        // where x_n == 2^(7 - n), and e^x_n = a_n has been precomputed. We choose the first x_n, x0, to equal 2^7
        // because all larger powers are larger than MAX_NATURAL_EXPONENT, and therefore not present in the
        // decomposition.
        // At the end of this process we will have the product of all e^x_n = a_n that apply, and the remainder of this
        // decomposition, which will be lower than the smallest x_n.
        // exp(x) = k_0 * a_0 * k_1 * a_1 * ... + k_n * a_n * exp(remainder), where each k_n equals either 0 or 1.
        // We mutate x by subtracting x_n, making it the remainder of the decomposition.
        // The first two a_n (e^(2^7) and e^(2^6)) are too large if stored as 18 decimal numbers, and could cause
        // intermediate overflows. Instead we store them as plain integers, with 0 decimals.
        // Additionally, x0 + x1 is larger than MAX_NATURAL_EXPONENT, which means they will not both be present in the
        // decomposition.
        // For each x_n, we test if that term is present in the decomposition (if x is larger than it), and if so deduct
        // it and compute the accumulated product.
        int256 firstAN;
        if (x >= x0) {
            x -= x0;
            firstAN = a0;
        } else if (x >= x1) {
            x -= x1;
            firstAN = a1;
        } else {
            firstAN = 1; // One with no decimal places
        }
        // We now transform x into a 20 decimal fixed point number, to have enhanced precision when computing the
        // smaller terms.
        x *= 100;
        // `product` is the accumulated product of all a_n (except a0 and a1), which starts at 20 decimal fixed point
        // one. Recall that fixed point multiplication requires dividing by ONE_20.
        int256 product = ONE_20;
        if (x >= x2) {
            x -= x2;
            product = (product * a2) / ONE_20;
        }
        if (x >= x3) {
            x -= x3;
            product = (product * a3) / ONE_20;
        }
        if (x >= x4) {
            x -= x4;
            product = (product * a4) / ONE_20;
        }
        if (x >= x5) {
            x -= x5;
            product = (product * a5) / ONE_20;
        }
        if (x >= x6) {
            x -= x6;
            product = (product * a6) / ONE_20;
        }
        if (x >= x7) {
            x -= x7;
            product = (product * a7) / ONE_20;
        }
        if (x >= x8) {
            x -= x8;
            product = (product * a8) / ONE_20;
        }
        if (x >= x9) {
            x -= x9;
            product = (product * a9) / ONE_20;
        }
        // x10 and x11 are unnecessary here since we have high enough precision already.
        // Now we need to compute e^x, where x is small (in particular, it is smaller than x9). We use the Taylor series
        // expansion for e^x: 1 + x + (x^2 / 2!) + (x^3 / 3!) + ... + (x^n / n!).
        int256 seriesSum = ONE_20; // The initial one in the sum, with 20 decimal places.
        int256 term; // Each term in the sum, where the nth term is (x^n / n!).
        // The first term is simply x.
        term = x;
        seriesSum += term;
        // Each term (x^n / n!) equals the previous one times x, divided by n. Since x is a fixed point number,
        // multiplying by it requires dividing by ONE_20, but dividing by the non-fixed point n values does not.
        term = ((term * x) / ONE_20) / 2;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 3;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 4;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 5;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 6;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 7;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 8;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 9;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 10;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 11;
        seriesSum += term;
        term = ((term * x) / ONE_20) / 12;
        seriesSum += term;
        // 12 Taylor terms are sufficient for 18 decimal precision.
        // We now have the first a_n (with no decimals), and the product of all other a_n present, and the Taylor
        // approximation of the exponentiation of the remainder (both with 20 decimals). All that remains is to multiply
        // all three (one 20 decimal fixed point multiplication, dividing by ONE_20, and one integer multiplication),
        // and then drop two digits to return an 18 decimal value.
        return (((product * seriesSum) / ONE_20) * firstAN) / 100;
    }
    /**
     * @dev Logarithm (log(arg, base), with signed 18 decimal fixed point base and argument.
     */
    function log(int256 arg, int256 base) internal pure returns (int256) {
        // This performs a simple base change: log(arg, base) = ln(arg) / ln(base).
        // Both logBase and logArg are computed as 36 decimal fixed point numbers, either by using ln_36, or by
        // upscaling.
        int256 logBase;
        if (LN_36_LOWER_BOUND < base && base < LN_36_UPPER_BOUND) {
            logBase = _ln_36(base);
        } else {
            logBase = _ln(base) * ONE_18;
        }
        int256 logArg;
        if (LN_36_LOWER_BOUND < arg && arg < LN_36_UPPER_BOUND) {
            logArg = _ln_36(arg);
        } else {
            logArg = _ln(arg) * ONE_18;
        }
        // When dividing, we multiply by ONE_18 to arrive at a result with 18 decimal places
        return (logArg * ONE_18) / logBase;
    }
    /**
     * @dev Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
     */
    function ln(int256 a) internal pure returns (int256) {
        // The real natural logarithm is not defined for negative numbers or zero.
        _require(a > 0, Errors.OUT_OF_BOUNDS);
        if (LN_36_LOWER_BOUND < a && a < LN_36_UPPER_BOUND) {
            return _ln_36(a) / ONE_18;
        } else {
            return _ln(a);
        }
    }
    /**
     * @dev Internal natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
     */
    function _ln(int256 a) private pure returns (int256) {
        if (a < ONE_18) {
            // Since ln(a^k) = k * ln(a), we can compute ln(a) as ln(a) = ln((1/a)^(-1)) = - ln((1/a)). If a is less
            // than one, 1/a will be greater than one, and this if statement will not be entered in the recursive call.
            // Fixed point division requires multiplying by ONE_18.
            return (-_ln((ONE_18 * ONE_18) / a));
        }
        // First, we use the fact that ln^(a * b) = ln(a) + ln(b) to decompose ln(a) into a sum of powers of two, which
        // we call x_n, where x_n == 2^(7 - n), which are the natural logarithm of precomputed quantities a_n (that is,
        // ln(a_n) = x_n). We choose the first x_n, x0, to equal 2^7 because the exponential of all larger powers cannot
        // be represented as 18 fixed point decimal numbers in 256 bits, and are therefore larger than a.
        // At the end of this process we will have the sum of all x_n = ln(a_n) that apply, and the remainder of this
        // decomposition, which will be lower than the smallest a_n.
        // ln(a) = k_0 * x_0 + k_1 * x_1 + ... + k_n * x_n + ln(remainder), where each k_n equals either 0 or 1.
        // We mutate a by subtracting a_n, making it the remainder of the decomposition.
        // For reasons related to how `exp` works, the first two a_n (e^(2^7) and e^(2^6)) are not stored as fixed point
        // numbers with 18 decimals, but instead as plain integers with 0 decimals, so we need to multiply them by
        // ONE_18 to convert them to fixed point.
        // For each a_n, we test if that term is present in the decomposition (if a is larger than it), and if so divide
        // by it and compute the accumulated sum.
        int256 sum = 0;
        if (a >= a0 * ONE_18) {
            a /= a0; // Integer, not fixed point division
            sum += x0;
        }
        if (a >= a1 * ONE_18) {
            a /= a1; // Integer, not fixed point division
            sum += x1;
        }
        // All other a_n and x_n are stored as 20 digit fixed point numbers, so we convert the sum and a to this format.
        sum *= 100;
        a *= 100;
        // Because further a_n are  20 digit fixed point numbers, we multiply by ONE_20 when dividing by them.
        if (a >= a2) {
            a = (a * ONE_20) / a2;
            sum += x2;
        }
        if (a >= a3) {
            a = (a * ONE_20) / a3;
            sum += x3;
        }
        if (a >= a4) {
            a = (a * ONE_20) / a4;
            sum += x4;
        }
        if (a >= a5) {
            a = (a * ONE_20) / a5;
            sum += x5;
        }
        if (a >= a6) {
            a = (a * ONE_20) / a6;
            sum += x6;
        }
        if (a >= a7) {
            a = (a * ONE_20) / a7;
            sum += x7;
        }
        if (a >= a8) {
            a = (a * ONE_20) / a8;
            sum += x8;
        }
        if (a >= a9) {
            a = (a * ONE_20) / a9;
            sum += x9;
        }
        if (a >= a10) {
            a = (a * ONE_20) / a10;
            sum += x10;
        }
        if (a >= a11) {
            a = (a * ONE_20) / a11;
            sum += x11;
        }
        // a is now a small number (smaller than a_11, which roughly equals 1.06). This means we can use a Taylor series
        // that converges rapidly for values of `a` close to one - the same one used in ln_36.
        // Let z = (a - 1) / (a + 1).
        // ln(a) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
        // Recall that 20 digit fixed point division requires multiplying by ONE_20, and multiplication requires
        // division by ONE_20.
        int256 z = ((a - ONE_20) * ONE_20) / (a + ONE_20);
        int256 z_squared = (z * z) / ONE_20;
        // num is the numerator of the series: the z^(2 * n + 1) term
        int256 num = z;
        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
        int256 seriesSum = num;
        // In each step, the numerator is multiplied by z^2
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 3;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 5;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 7;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 9;
        num = (num * z_squared) / ONE_20;
        seriesSum += num / 11;
        // 6 Taylor terms are sufficient for 36 decimal precision.
        // Finally, we multiply by 2 (non fixed point) to compute ln(remainder)
        seriesSum *= 2;
        // We now have the sum of all x_n present, and the Taylor approximation of the logarithm of the remainder (both
        // with 20 decimals). All that remains is to sum these two, and then drop two digits to return a 18 decimal
        // value.
        return (sum + seriesSum) / 100;
    }
    /**
     * @dev Intrnal high precision (36 decimal places) natural logarithm (ln(x)) with signed 18 decimal fixed point argument,
     * for x close to one.
     *
     * Should only be used if x is between LN_36_LOWER_BOUND and LN_36_UPPER_BOUND.
     */
    function _ln_36(int256 x) private pure returns (int256) {
        // Since ln(1) = 0, a value of x close to one will yield a very small result, which makes using 36 digits
        // worthwhile.
        // First, we transform x to a 36 digit fixed point value.
        x *= ONE_18;
        // We will use the following Taylor expansion, which converges very rapidly. Let z = (x - 1) / (x + 1).
        // ln(x) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
        // Recall that 36 digit fixed point division requires multiplying by ONE_36, and multiplication requires
        // division by ONE_36.
        int256 z = ((x - ONE_36) * ONE_36) / (x + ONE_36);
        int256 z_squared = (z * z) / ONE_36;
        // num is the numerator of the series: the z^(2 * n + 1) term
        int256 num = z;
        // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
        int256 seriesSum = num;
        // In each step, the numerator is multiplied by z^2
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 3;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 5;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 7;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 9;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 11;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 13;
        num = (num * z_squared) / ONE_36;
        seriesSum += num / 15;
        // 8 Taylor terms are sufficient for 36 decimal precision.
        // All that remains is multiplying by 2 (non fixed point).
        return seriesSum * 2;
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "./IBasePool.sol";
/**
 * @dev IPools with the General specialization setting should implement this interface.
 *
 * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
 * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will
 * grant to the pool in a 'given out' swap.
 *
 * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
 * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
 * indeed the Vault.
 */
interface IGeneralPool is IBasePool {
    function onSwap(
        SwapRequest memory swapRequest,
        uint256[] memory balances,
        uint256 indexIn,
        uint256 indexOut
    ) external returns (uint256 amount);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IAssetManager.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IControlledPool.sol";
import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
import "@balancer-labs/v2-interfaces/contracts/vault/IBasePool.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/TemporarilyPausable.sol";
import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
import "./BalancerPoolToken.sol";
import "./BasePoolAuthorization.sol";
import "./RecoveryMode.sol";
// solhint-disable max-states-count
/**
 * @notice Reference implementation for the base layer of a Pool contract.
 * @dev Reference implementation for the base layer of a Pool contract that manages a single Pool with optional
 * Asset Managers, an admin-controlled swap fee percentage, and an emergency pause mechanism.
 *
 * This Pool pays protocol fees by minting BPT directly to the ProtocolFeeCollector instead of using the
 * `dueProtocolFees` return value. This results in the underlying tokens continuing to provide liquidity
 * for traders, while still keeping gas usage to a minimum since only a single token (the BPT) is transferred.
 *
 * Note that neither swap fees nor the pause mechanism are used by this contract. They are passed through so that
 * derived contracts can use them via the `_addSwapFeeAmount` and `_subtractSwapFeeAmount` functions, and the
 * `whenNotPaused` modifier.
 *
 * No admin permissions are checked here: instead, this contract delegates that to the Vault's own Authorizer.
 *
 * Because this contract doesn't implement the swap hooks, derived contracts should generally inherit from
 * BaseGeneralPool or BaseMinimalSwapInfoPool. Otherwise, subclasses must inherit from the corresponding interfaces
 * and implement the swap callbacks themselves.
 */
abstract contract BasePool is
    IBasePool,
    IControlledPool,
    BasePoolAuthorization,
    BalancerPoolToken,
    TemporarilyPausable,
    RecoveryMode
{
    using WordCodec for bytes32;
    using FixedPoint for uint256;
    using BasePoolUserData for bytes;
    uint256 private constant _MIN_TOKENS = 2;
    uint256 private constant _DEFAULT_MINIMUM_BPT = 1e6;
    // 1e18 corresponds to 1.0, or a 100% fee
    uint256 private constant _MIN_SWAP_FEE_PERCENTAGE = 1e12; // 0.0001%
    uint256 private constant _MAX_SWAP_FEE_PERCENTAGE = 1e17; // 10% - this fits in 64 bits
    // `_miscData` is a storage slot that can be used to store unrelated pieces of information. All pools store the
    // recovery mode flag and swap fee percentage, but `miscData` can be extended to store more pieces of information.
    // The most signficant bit is reserved for the recovery mode flag, and the swap fee percentage is stored in
    // the next most significant 63 bits, leaving the remaining 192 bits free to store any other information derived
    // pools might need.
    //
    // This slot is preferred for gas-sensitive operations as it is read in all joins, swaps and exits,
    // and therefore warm.
    // [ recovery | swap  fee | available ]
    // [   1 bit  |  63 bits  |  192 bits ]
    // [ MSB                          LSB ]
    bytes32 private _miscData;
    uint256 private constant _SWAP_FEE_PERCENTAGE_OFFSET = 192;
    uint256 private constant _RECOVERY_MODE_BIT_OFFSET = 255;
    // A fee can never be larger than FixedPoint.ONE, which fits in 60 bits, so 63 is more than enough.
    uint256 private constant _SWAP_FEE_PERCENTAGE_BIT_LENGTH = 63;
    bytes32 private immutable _poolId;
    // Note that this value is immutable in the Vault, so we can make it immutable here and save gas
    IProtocolFeesCollector private immutable _protocolFeesCollector;
    event SwapFeePercentageChanged(uint256 swapFeePercentage);
    constructor(
        IVault vault,
        IVault.PoolSpecialization specialization,
        string memory name,
        string memory symbol,
        IERC20[] memory tokens,
        address[] memory assetManagers,
        uint256 swapFeePercentage,
        uint256 pauseWindowDuration,
        uint256 bufferPeriodDuration,
        address owner
    )
        // Base Pools are expected to be deployed using factories. By using the factory address as the action
        // disambiguator, we make all Pools deployed by the same factory share action identifiers. This allows for
        // simpler management of permissions (such as being able to manage granting the 'set fee percentage' action in
        // any Pool created by the same factory), while still making action identifiers unique among different factories
        // if the selectors match, preventing accidental errors.
        Authentication(bytes32(uint256(msg.sender)))
        BalancerPoolToken(name, symbol, vault)
        BasePoolAuthorization(owner)
        TemporarilyPausable(pauseWindowDuration, bufferPeriodDuration)
    {
        _require(tokens.length >= _MIN_TOKENS, Errors.MIN_TOKENS);
        _require(tokens.length <= _getMaxTokens(), Errors.MAX_TOKENS);
        // The Vault only requires the token list to be ordered for the Two Token Pools specialization. However,
        // to make the developer experience consistent, we are requiring this condition for all the native pools.
        // Also, since these Pools will register tokens only once, we can ensure the Pool tokens will follow the same
        // order. We rely on this property to make Pools simpler to write, as it lets us assume that the
        // order of token-specific parameters (such as token weights) will not change.
        InputHelpers.ensureArrayIsSorted(tokens);
        _setSwapFeePercentage(swapFeePercentage);
        bytes32 poolId = vault.registerPool(specialization);
        vault.registerTokens(poolId, tokens, assetManagers);
        // Set immutable state variables - these cannot be read from during construction
        _poolId = poolId;
        _protocolFeesCollector = vault.getProtocolFeesCollector();
    }
    // Getters / Setters
    /**
     * @notice Return the pool id.
     */
    function getPoolId() public view override returns (bytes32) {
        return _poolId;
    }
    function _getTotalTokens() internal view virtual returns (uint256);
    function _getMaxTokens() internal pure virtual returns (uint256);
    /**
     * @dev Returns the minimum BPT supply. This amount is minted to the zero address during initialization, effectively
     * locking it.
     *
     * This is useful to make sure Pool initialization happens only once, but derived Pools can change this value (even
     * to zero) by overriding this function.
     */
    function _getMinimumBpt() internal pure virtual returns (uint256) {
        return _DEFAULT_MINIMUM_BPT;
    }
    /**
     * @notice Return the current value of the swap fee percentage.
     * @dev This is stored in `_miscData`.
     */
    function getSwapFeePercentage() public view virtual override returns (uint256) {
        return _miscData.decodeUint(_SWAP_FEE_PERCENTAGE_OFFSET, _SWAP_FEE_PERCENTAGE_BIT_LENGTH);
    }
    /**
     * @notice Return the ProtocolFeesCollector contract.
     * @dev This is immutable, and retrieved from the Vault on construction. (It is also immutable in the Vault.)
     */
    function getProtocolFeesCollector() public view returns (IProtocolFeesCollector) {
        return _protocolFeesCollector;
    }
    /**
     * @notice Set the swap fee percentage.
     * @dev This is a permissioned function, and disabled if the pool is paused. The swap fee must be within the
     * bounds set by MIN_SWAP_FEE_PERCENTAGE/MAX_SWAP_FEE_PERCENTAGE. Emits the SwapFeePercentageChanged event.
     */
    function setSwapFeePercentage(uint256 swapFeePercentage) public virtual override authenticate whenNotPaused {
        _setSwapFeePercentage(swapFeePercentage);
    }
    function _setSwapFeePercentage(uint256 swapFeePercentage) internal virtual {
        _require(swapFeePercentage >= _getMinSwapFeePercentage(), Errors.MIN_SWAP_FEE_PERCENTAGE);
        _require(swapFeePercentage <= _getMaxSwapFeePercentage(), Errors.MAX_SWAP_FEE_PERCENTAGE);
        _miscData = _miscData.insertUint(
            swapFeePercentage,
            _SWAP_FEE_PERCENTAGE_OFFSET,
            _SWAP_FEE_PERCENTAGE_BIT_LENGTH
        );
        emit SwapFeePercentageChanged(swapFeePercentage);
    }
    function _getMinSwapFeePercentage() internal pure virtual returns (uint256) {
        return _MIN_SWAP_FEE_PERCENTAGE;
    }
    function _getMaxSwapFeePercentage() internal pure virtual returns (uint256) {
        return _MAX_SWAP_FEE_PERCENTAGE;
    }
    /**
     * @notice Returns whether the pool is in Recovery Mode.
     */
    function inRecoveryMode() public view override returns (bool) {
        return _miscData.decodeBool(_RECOVERY_MODE_BIT_OFFSET);
    }
    /**
     * @dev Sets the recoveryMode state, and emits the corresponding event.
     */
    function _setRecoveryMode(bool enabled) internal virtual override {
        _miscData = _miscData.insertBool(enabled, _RECOVERY_MODE_BIT_OFFSET);
        emit RecoveryModeStateChanged(enabled);
        // Some pools need to update their state when leaving recovery mode to ensure proper functioning of the Pool.
        // We do not allow an `_onEnableRecoveryMode()` hook as this may jeopardize the ability to enable Recovery mode.
        if (!enabled) _onDisableRecoveryMode();
    }
    /**
     * @dev Performs any necessary actions on the disabling of Recovery Mode.
     * This is usually to reset any fee collection mechanisms to ensure that they operate correctly going forward.
     */
    function _onDisableRecoveryMode() internal virtual {}
    /**
     * @notice Set the asset manager parameters for the given token.
     * @dev This is a permissioned function, unavailable when the pool is paused.
     * The details of the configuration data are set by each Asset Manager. (For an example, see
     * `RewardsAssetManager`.)
     */
    function setAssetManagerPoolConfig(IERC20 token, bytes memory poolConfig)
        public
        virtual
        override
        authenticate
        whenNotPaused
    {
        _setAssetManagerPoolConfig(token, poolConfig);
    }
    function _setAssetManagerPoolConfig(IERC20 token, bytes memory poolConfig) private {
        bytes32 poolId = getPoolId();
        (, , , address assetManager) = getVault().getPoolTokenInfo(poolId, token);
        IAssetManager(assetManager).setConfig(poolId, poolConfig);
    }
    /**
     * @notice Pause the pool: an emergency action which disables all pool functions.
     * @dev This is a permissioned function that will only work during the Pause Window set during pool factory
     * deployment (see `TemporarilyPausable`).
     */
    function pause() external authenticate {
        _setPaused(true);
    }
    /**
     * @notice Reverse a `pause` operation, and restore a pool to normal functionality.
     * @dev This is a permissioned function that will only work on a paused pool within the Buffer Period set during
     * pool factory deployment (see `TemporarilyPausable`). Note that any paused pools will automatically unpause
     * after the Buffer Period expires.
     */
    function unpause() external authenticate {
        _setPaused(false);
    }
    function _isOwnerOnlyAction(bytes32 actionId) internal view virtual override returns (bool) {
        return
            (actionId == getActionId(this.setSwapFeePercentage.selector)) ||
            (actionId == getActionId(this.setAssetManagerPoolConfig.selector)) ||
            super._isOwnerOnlyAction(actionId);
    }
    function _getMiscData() internal view returns (bytes32) {
        return _miscData;
    }
    /**
     * @dev Inserts data into the least-significant 192 bits of the misc data storage slot.
     * Note that the remaining 64 bits are used for the swap fee percentage and cannot be overloaded.
     */
    function _setMiscData(bytes32 newData) internal {
        _miscData = _miscData.insertBits192(newData, 0);
    }
    // Join / Exit Hooks
    modifier onlyVault(bytes32 poolId) {
        _require(msg.sender == address(getVault()), Errors.CALLER_NOT_VAULT);
        _require(poolId == getPoolId(), Errors.INVALID_POOL_ID);
        _;
    }
    /**
     * @notice Vault hook for adding liquidity to a pool (including the first time, "initializing" the pool).
     * @dev This function can only be called from the Vault, from `joinPool`.
     */
    function onJoinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external override onlyVault(poolId) returns (uint256[] memory, uint256[] memory) {
        _beforeSwapJoinExit();
        uint256[] memory scalingFactors = _scalingFactors();
        if (totalSupply() == 0) {
            (uint256 bptAmountOut, uint256[] memory amountsIn) = _onInitializePool(
                poolId,
                sender,
                recipient,
                scalingFactors,
                userData
            );
            // On initialization, we lock _getMinimumBpt() by minting it for the zero address. This BPT acts as a
            // minimum as it will never be burned, which reduces potential issues with rounding, and also prevents the
            // Pool from ever being fully drained.
            _require(bptAmountOut >= _getMinimumBpt(), Errors.MINIMUM_BPT);
            _mintPoolTokens(address(0), _getMinimumBpt());
            _mintPoolTokens(recipient, bptAmountOut - _getMinimumBpt());
            // amountsIn are amounts entering the Pool, so we round up.
            _downscaleUpArray(amountsIn, scalingFactors);
            return (amountsIn, new uint256[](balances.length));
        } else {
            _upscaleArray(balances, scalingFactors);
            (uint256 bptAmountOut, uint256[] memory amountsIn) = _onJoinPool(
                poolId,
                sender,
                recipient,
                balances,
                lastChangeBlock,
                inRecoveryMode() ? 0 : protocolSwapFeePercentage, // Protocol fees are disabled while in recovery mode
                scalingFactors,
                userData
            );
            // Note we no longer use `balances` after calling `_onJoinPool`, which may mutate it.
            _mintPoolTokens(recipient, bptAmountOut);
            // amountsIn are amounts entering the Pool, so we round up.
            _downscaleUpArray(amountsIn, scalingFactors);
            // This Pool ignores the `dueProtocolFees` return value, so we simply return a zeroed-out array.
            return (amountsIn, new uint256[](balances.length));
        }
    }
    /**
     * @notice Vault hook for removing liquidity from a pool.
     * @dev This function can only be called from the Vault, from `exitPool`.
     */
    function onExitPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external override onlyVault(poolId) returns (uint256[] memory, uint256[] memory) {
        uint256[] memory amountsOut;
        uint256 bptAmountIn;
        // When a user calls `exitPool`, this is the first point of entry from the Vault.
        // We first check whether this is a Recovery Mode exit - if so, we proceed using this special lightweight exit
        // mechanism which avoids computing any complex values, interacting with external contracts, etc., and generally
        // should always work, even if the Pool's mathematics or a dependency break down.
        if (userData.isRecoveryModeExitKind()) {
            // This exit kind is only available in Recovery Mode.
            _ensureInRecoveryMode();
            // Note that we don't upscale balances nor downscale amountsOut - we don't care about scaling factors during
            // a recovery mode exit.
            (bptAmountIn, amountsOut) = _doRecoveryModeExit(balances, totalSupply(), userData);
        } else {
            // Note that we only call this if we're not in a recovery mode exit.
            _beforeSwapJoinExit();
            uint256[] memory scalingFactors = _scalingFactors();
            _upscaleArray(balances, scalingFactors);
            (bptAmountIn, amountsOut) = _onExitPool(
                poolId,
                sender,
                recipient,
                balances,
                lastChangeBlock,
                inRecoveryMode() ? 0 : protocolSwapFeePercentage, // Protocol fees are disabled while in recovery mode
                scalingFactors,
                userData
            );
            // amountsOut are amounts exiting the Pool, so we round down.
            _downscaleDownArray(amountsOut, scalingFactors);
        }
        // Note we no longer use `balances` after calling `_onExitPool`, which may mutate it.
        _burnPoolTokens(sender, bptAmountIn);
        // This Pool ignores the `dueProtocolFees` return value, so we simply return a zeroed-out array.
        return (amountsOut, new uint256[](balances.length));
    }
    // Query functions
    /**
     * @notice "Dry run" `onJoinPool`.
     * @dev Returns the amount of BPT that would be granted to `recipient` if the `onJoinPool` hook were called by the
     * Vault with the same arguments, along with the number of tokens `sender` would have to supply.
     *
     * This function is not meant to be called directly, but rather from a helper contract that fetches current Vault
     * data, such as the protocol swap fee percentage and Pool balances.
     *
     * Like `IVault.queryBatchSwap`, this function is not view due to internal implementation details: the caller must
     * explicitly use eth_call instead of eth_sendTransaction.
     */
    function queryJoin(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external override returns (uint256 bptOut, uint256[] memory amountsIn) {
        InputHelpers.ensureInputLengthMatch(balances.length, _getTotalTokens());
        _queryAction(
            poolId,
            sender,
            recipient,
            balances,
            lastChangeBlock,
            protocolSwapFeePercentage,
            userData,
            _onJoinPool,
            _downscaleUpArray
        );
        // The `return` opcode is executed directly inside `_queryAction`, so execution never reaches this statement,
        // and we don't need to return anything here - it just silences compiler warnings.
        return (bptOut, amountsIn);
    }
    /**
     * @notice "Dry run" `onExitPool`.
     * @dev Returns the amount of BPT that would be burned from `sender` if the `onExitPool` hook were called by the
     * Vault with the same arguments, along with the number of tokens `recipient` would receive.
     *
     * This function is not meant to be called directly, but rather from a helper contract that fetches current Vault
     * data, such as the protocol swap fee percentage and Pool balances.
     *
     * Like `IVault.queryBatchSwap`, this function is not view due to internal implementation details: the caller must
     * explicitly use eth_call instead of eth_sendTransaction.
     */
    function queryExit(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external override returns (uint256 bptIn, uint256[] memory amountsOut) {
        InputHelpers.ensureInputLengthMatch(balances.length, _getTotalTokens());
        _queryAction(
            poolId,
            sender,
            recipient,
            balances,
            lastChangeBlock,
            protocolSwapFeePercentage,
            userData,
            _onExitPool,
            _downscaleDownArray
        );
        // The `return` opcode is executed directly inside `_queryAction`, so execution never reaches this statement,
        // and we don't need to return anything here - it just silences compiler warnings.
        return (bptIn, amountsOut);
    }
    // Internal hooks to be overridden by derived contracts - all token amounts (except BPT) in these interfaces are
    // upscaled.
    /**
     * @dev Called when the Pool is joined for the first time; that is, when the BPT total supply is zero.
     *
     * Returns the amount of BPT to mint, and the token amounts the Pool will receive in return.
     *
     * Minted BPT will be sent to `recipient`, except for _getMinimumBpt(), which will be deducted from this amount and
     * sent to the zero address instead. This will cause that BPT to remain forever locked there, preventing total BTP
     * from ever dropping below that value, and ensuring `_onInitializePool` can only be called once in the entire
     * Pool's lifetime.
     *
     * The tokens granted to the Pool will be transferred from `sender`. These amounts are considered upscaled and will
     * be downscaled (rounding up) before being returned to the Vault.
     */
    function _onInitializePool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal virtual returns (uint256 bptAmountOut, uint256[] memory amountsIn);
    /**
     * @dev Called whenever the Pool is joined after the first initialization join (see `_onInitializePool`).
     *
     * Returns the amount of BPT to mint, the token amounts that the Pool will receive in return, and the number of
     * tokens to pay in protocol swap fees.
     *
     * Implementations of this function might choose to mutate the `balances` array to save gas (e.g. when
     * performing intermediate calculations, such as subtraction of due protocol fees). This can be done safely.
     *
     * Minted BPT will be sent to `recipient`.
     *
     * The tokens granted to the Pool will be transferred from `sender`. These amounts are considered upscaled and will
     * be downscaled (rounding up) before being returned to the Vault.
     *
     * Due protocol swap fees will be taken from the Pool's balance in the Vault (see `IBasePool.onJoinPool`). These
     * amounts are considered upscaled and will be downscaled (rounding down) before being returned to the Vault.
     */
    function _onJoinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal virtual returns (uint256 bptAmountOut, uint256[] memory amountsIn);
    /**
     * @dev Called whenever the Pool is exited.
     *
     * Returns the amount of BPT to burn, the token amounts for each Pool token that the Pool will grant in return, and
     * the number of tokens to pay in protocol swap fees.
     *
     * Implementations of this function might choose to mutate the `balances` array to save gas (e.g. when
     * performing intermediate calculations, such as subtraction of due protocol fees). This can be done safely.
     *
     * BPT will be burnt from `sender`.
     *
     * The Pool will grant tokens to `recipient`. These amounts are considered upscaled and will be downscaled
     * (rounding down) before being returned to the Vault.
     *
     * Due protocol swap fees will be taken from the Pool's balance in the Vault (see `IBasePool.onExitPool`). These
     * amounts are considered upscaled and will be downscaled (rounding down) before being returned to the Vault.
     */
    function _onExitPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        uint256[] memory scalingFactors,
        bytes memory userData
    ) internal virtual returns (uint256 bptAmountIn, uint256[] memory amountsOut);
    /**
     * @dev Called at the very beginning of swaps, joins and exits, even before the scaling factors are read. Derived
     * contracts can extend this implementation to perform any state-changing operations they might need (including e.g.
     * updating the scaling factors),
     *
     * The only scenario in which this function is not called is during a recovery mode exit. This makes it safe to
     * perform non-trivial computations or interact with external dependencies here, as recovery mode will not be
     * affected.
     *
     * Since this contract does not implement swaps, derived contracts must also make sure this function is called on
     * swap handlers.
     */
    function _beforeSwapJoinExit() internal virtual {
        // All joins, exits and swaps are disabled (except recovery mode exits).
        _ensureNotPaused();
    }
    // Internal functions
    /**
     * @dev Pays protocol fees by minting `bptAmount` to the Protocol Fee Collector.
     */
    function _payProtocolFees(uint256 bptAmount) internal {
        _mintPoolTokens(address(getProtocolFeesCollector()), bptAmount);
    }
    /**
     * @dev Adds swap fee amount to `amount`, returning a higher value.
     */
    function _addSwapFeeAmount(uint256 amount) internal view returns (uint256) {
        // This returns amount + fee amount, so we round up (favoring a higher fee amount).
        return amount.divUp(getSwapFeePercentage().complement());
    }
    /**
     * @dev Subtracts swap fee amount from `amount`, returning a lower value.
     */
    function _subtractSwapFeeAmount(uint256 amount) internal view returns (uint256) {
        // This returns amount - fee amount, so we round up (favoring a higher fee amount).
        uint256 feeAmount = amount.mulUp(getSwapFeePercentage());
        return amount.sub(feeAmount);
    }
    // Scaling
    /**
     * @dev Returns a scaling factor that, when multiplied to a token amount for `token`, normalizes its balance as if
     * it had 18 decimals.
     */
    function _computeScalingFactor(IERC20 token) internal view returns (uint256) {
        if (address(token) == address(this)) {
            return FixedPoint.ONE;
        }
        // Tokens that don't implement the `decimals` method are not supported.
        uint256 tokenDecimals = ERC20(address(token)).decimals();
        // Tokens with more than 18 decimals are not supported.
        uint256 decimalsDifference = Math.sub(18, tokenDecimals);
        return FixedPoint.ONE * 10**decimalsDifference;
    }
    /**
     * @dev Returns the scaling factor for one of the Pool's tokens. Reverts if `token` is not a token registered by the
     * Pool.
     *
     * All scaling factors are fixed-point values with 18 decimals, to allow for this function to be overridden by
     * derived contracts that need to apply further scaling, making these factors potentially non-integer.
     *
     * The largest 'base' scaling factor (i.e. in tokens with less than 18 decimals) is 10**18, which in fixed-point is
     * 10**36. This value can be multiplied with a 112 bit Vault balance with no overflow by a factor of ~1e7, making
     * even relatively 'large' factors safe to use.
     *
     * The 1e7 figure is the result of 2**256 / (1e18 * 1e18 * 2**112).
     */
    function _scalingFactor(IERC20 token) internal view virtual returns (uint256);
    /**
     * @dev Same as `_scalingFactor()`, except for all registered tokens (in the same order as registered). The Vault
     * will always pass balances in this order when calling any of the Pool hooks.
     */
    function _scalingFactors() internal view virtual returns (uint256[] memory);
    function getScalingFactors() external view override returns (uint256[] memory) {
        return _scalingFactors();
    }
    /**
     * @dev Applies `scalingFactor` to `amount`, resulting in a larger or equal value depending on whether it needed
     * scaling or not.
     */
    function _upscale(uint256 amount, uint256 scalingFactor) internal pure returns (uint256) {
        // Upscale rounding wouldn't necessarily always go in the same direction: in a swap for example the balance of
        // token in should be rounded up, and that of token out rounded down. This is the only place where we round in
        // the same direction for all amounts, as the impact of this rounding is expected to be minimal (and there's no
        // rounding error unless `_scalingFactor()` is overriden).
        return FixedPoint.mulDown(amount, scalingFactor);
    }
    /**
     * @dev Same as `_upscale`, but for an entire array. This function does not return anything, but instead *mutates*
     * the `amounts` array.
     */
    function _upscaleArray(uint256[] memory amounts, uint256[] memory scalingFactors) internal pure {
        uint256 length = amounts.length;
        InputHelpers.ensureInputLengthMatch(length, scalingFactors.length);
        for (uint256 i = 0; i < length; ++i) {
            amounts[i] = FixedPoint.mulDown(amounts[i], scalingFactors[i]);
        }
    }
    /**
     * @dev Reverses the `scalingFactor` applied to `amount`, resulting in a smaller or equal value depending on
     * whether it needed scaling or not. The result is rounded down.
     */
    function _downscaleDown(uint256 amount, uint256 scalingFactor) internal pure returns (uint256) {
        return FixedPoint.divDown(amount, scalingFactor);
    }
    /**
     * @dev Same as `_downscaleDown`, but for an entire array. This function does not return anything, but instead
     * *mutates* the `amounts` array.
     */
    function _downscaleDownArray(uint256[] memory amounts, uint256[] memory scalingFactors) internal pure {
        uint256 length = amounts.length;
        InputHelpers.ensureInputLengthMatch(length, scalingFactors.length);
        for (uint256 i = 0; i < length; ++i) {
            amounts[i] = FixedPoint.divDown(amounts[i], scalingFactors[i]);
        }
    }
    /**
     * @dev Reverses the `scalingFactor` applied to `amount`, resulting in a smaller or equal value depending on
     * whether it needed scaling or not. The result is rounded up.
     */
    function _downscaleUp(uint256 amount, uint256 scalingFactor) internal pure returns (uint256) {
        return FixedPoint.divUp(amount, scalingFactor);
    }
    /**
     * @dev Same as `_downscaleUp`, but for an entire array. This function does not return anything, but instead
     * *mutates* the `amounts` array.
     */
    function _downscaleUpArray(uint256[] memory amounts, uint256[] memory scalingFactors) internal pure {
        uint256 length = amounts.length;
        InputHelpers.ensureInputLengthMatch(length, scalingFactors.length);
        for (uint256 i = 0; i < length; ++i) {
            amounts[i] = FixedPoint.divUp(amounts[i], scalingFactors[i]);
        }
    }
    function _getAuthorizer() internal view override returns (IAuthorizer) {
        // Access control management is delegated to the Vault's Authorizer. This lets Balancer Governance manage which
        // accounts can call permissioned functions: for example, to perform emergency pauses.
        // If the owner is delegated, then *all* permissioned functions, including `setSwapFeePercentage`, will be under
        // Governance control.
        return getVault().getAuthorizer();
    }
    function _queryAction(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData,
        function(bytes32, address, address, uint256[] memory, uint256, uint256, uint256[] memory, bytes memory)
            internal
            returns (uint256, uint256[] memory) _action,
        function(uint256[] memory, uint256[] memory) internal view _downscaleArray
    ) private {
        // This uses the same technique used by the Vault in queryBatchSwap. Refer to that function for a detailed
        // explanation.
        if (msg.sender != address(this)) {
            // We perform an external call to ourselves, forwarding the same calldata. In this call, the else clause of
            // the preceding if statement will be executed instead.
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, ) = address(this).call(msg.data);
            // solhint-disable-next-line no-inline-assembly
            assembly {
                // This call should always revert to decode the bpt and token amounts from the revert reason
                switch success
                    case 0 {
                        // Note we are manually writing the memory slot 0. We can safely overwrite whatever is
                        // stored there as we take full control of the execution and then immediately return.
                        // We copy the first 4 bytes to check if it matches with the expected signature, otherwise
                        // there was another revert reason and we should forward it.
                        returndatacopy(0, 0, 0x04)
                        let error := and(mload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
                        // If the first 4 bytes don't match with the expected signature, we forward the revert reason.
                        if eq(eq(error, 0x43adbafb00000000000000000000000000000000000000000000000000000000), 0) {
                            returndatacopy(0, 0, returndatasize())
                            revert(0, returndatasize())
                        }
                        // The returndata contains the signature, followed by the raw memory representation of the
                        // `bptAmount` and `tokenAmounts` (array: length + data). We need to return an ABI-encoded
                        // representation of these.
                        // An ABI-encoded response will include one additional field to indicate the starting offset of
                        // the `tokenAmounts` array. The `bptAmount` will be laid out in the first word of the
                        // returndata.
                        //
                        // In returndata:
                        // [ signature ][ bptAmount ][ tokenAmounts length ][ tokenAmounts values ]
                        // [  4 bytes  ][  32 bytes ][       32 bytes      ][ (32 * length) bytes ]
                        //
                        // We now need to return (ABI-encoded values):
                        // [ bptAmount ][ tokeAmounts offset ][ tokenAmounts length ][ tokenAmounts values ]
                        // [  32 bytes ][       32 bytes     ][       32 bytes      ][ (32 * length) bytes ]
                        // We copy 32 bytes for the `bptAmount` from returndata into memory.
                        // Note that we skip the first 4 bytes for the error signature
                        returndatacopy(0, 0x04, 32)
                        // The offsets are 32-bytes long, so the array of `tokenAmounts` will start after
                        // the initial 64 bytes.
                        mstore(0x20, 64)
                        // We now copy the raw memory array for the `tokenAmounts` from returndata into memory.
                        // Since bpt amount and offset take up 64 bytes, we start copying at address 0x40. We also
                        // skip the first 36 bytes from returndata, which correspond to the signature plus bpt amount.
                        returndatacopy(0x40, 0x24, sub(returndatasize(), 36))
                        // We finally return the ABI-encoded uint256 and the array, which has a total length equal to
                        // the size of returndata, plus the 32 bytes of the offset but without the 4 bytes of the
                        // error signature.
                        return(0, add(returndatasize(), 28))
                    }
                    default {
                        // This call should always revert, but we fail nonetheless if that didn't happen
                        invalid()
                    }
            }
        } else {
            // This imitates the relevant parts of the bodies of onJoin and onExit. Since they're not virtual, we know
            // that their implementations will match this regardless of what derived contracts might do.
            _beforeSwapJoinExit();
            uint256[] memory scalingFactors = _scalingFactors();
            _upscaleArray(balances, scalingFactors);
            (uint256 bptAmount, uint256[] memory tokenAmounts) = _action(
                poolId,
                sender,
                recipient,
                balances,
                lastChangeBlock,
                protocolSwapFeePercentage,
                scalingFactors,
                userData
            );
            _downscaleArray(tokenAmounts, scalingFactors);
            // solhint-disable-next-line no-inline-assembly
            assembly {
                // We will return a raw representation of `bptAmount` and `tokenAmounts` in memory, which is composed of
                // a 32-byte uint256, followed by a 32-byte for the array length, and finally the 32-byte uint256 values
                // Because revert expects a size in bytes, we multiply the array length (stored at `tokenAmounts`) by 32
                let size := mul(mload(tokenAmounts), 32)
                // We store the `bptAmount` in the previous slot to the `tokenAmounts` array. We can make sure there
                // will be at least one available slot due to how the memory scratch space works.
                // We can safely overwrite whatever is stored in this slot as we will revert immediately after that.
                let start := sub(tokenAmounts, 0x20)
                mstore(start, bptAmount)
                // We send one extra value for the error signature "QueryError(uint256,uint256[])" which is 0x43adbafb
                // We use the previous slot to `bptAmount`.
                mstore(sub(start, 0x20), 0x0000000000000000000000000000000000000000000000000000000043adbafb)
                start := sub(start, 0x04)
                // When copying from `tokenAmounts` into returndata, we copy the additional 68 bytes to also return
                // the `bptAmount`, the array 's length, and the error signature.
                revert(start, add(size, 68))
            }
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "./IVault.sol";
import "./IPoolSwapStructs.sol";
/**
 * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
 * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
 * either IGeneralPool or IMinimalSwapInfoPool
 */
interface IBasePool is IPoolSwapStructs {
    /**
     * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
     * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
     * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
     * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
     *
     * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
     *
     * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
     * designated to receive any benefits (typically pool shares). `balances` contains the total balances
     * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
     *
     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
     * balance.
     *
     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
     * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
     *
     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
     * state-changing operations, such as minting pool shares.
     */
    function onJoinPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);
    /**
     * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
     * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
     * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
     * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
     * `protocolSwapFeePercentage`.
     *
     * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
     *
     * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
     * to which the Vault will send the proceeds. `balances` contains the total token balances for each token
     * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
     *
     * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
     * balance.
     *
     * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
     * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
     *
     * Contracts implementing this function should check that the caller is indeed the Vault before performing any
     * state-changing operations, such as burning pool shares.
     */
    function onExitPool(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);
    /**
     * @dev Returns this Pool's ID, used when interacting with the Vault (to e.g. join the Pool or swap with it).
     */
    function getPoolId() external view returns (bytes32);
    /**
     * @dev Returns the current swap fee percentage as a 18 decimal fixed point number, so e.g. 1e17 corresponds to a
     * 10% swap fee.
     */
    function getSwapFeePercentage() external view returns (uint256);
    /**
     * @dev Returns the scaling factors of each of the Pool's tokens. This is an implementation detail that is typically
     * not relevant for outside parties, but which might be useful for some types of Pools.
     */
    function getScalingFactors() external view returns (uint256[] memory);
    function queryJoin(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256 bptOut, uint256[] memory amountsIn);
    function queryExit(
        bytes32 poolId,
        address sender,
        address recipient,
        uint256[] memory balances,
        uint256 lastChangeBlock,
        uint256 protocolSwapFeePercentage,
        bytes memory userData
    ) external returns (uint256 bptIn, uint256[] memory amountsOut);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../solidity-utils/openzeppelin/IERC20.sol";
import "./IVault.sol";
interface IPoolSwapStructs {
    // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
    // IMinimalSwapInfoPool.
    //
    // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
    // 'given out') which indicates whether or not the amount sent by the pool is known.
    //
    // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
    // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
    //
    // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
    // some Pools.
    //
    // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
    // one Pool.
    //
    // The meaning of `lastChangeBlock` depends on the Pool specialization:
    //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
    //    balance.
    //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
    //
    // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
    // where the Pool sends the outgoing tokens.
    //
    // `userData` is extra data provided by the caller - typically a signature from a trusted party.
    struct SwapRequest {
        IVault.SwapKind kind;
        IERC20 tokenIn;
        IERC20 tokenOut;
        uint256 amount;
        // Misc data
        bytes32 poolId;
        uint256 lastChangeBlock;
        address from;
        address to;
        bytes userData;
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
pragma experimental ABIEncoderV2;
import "../solidity-utils/openzeppelin/IERC20.sol";
interface IAssetManager {
    /**
     * @notice Emitted when asset manager is rebalanced
     */
    event Rebalance(bytes32 poolId);
    /**
     * @notice Sets the config
     */
    function setConfig(bytes32 poolId, bytes calldata config) external;
    /**
     * Note: No function to read the asset manager config is included in IAssetManager
     * as the signature is expected to vary between asset manager implementations
     */
    /**
     * @notice Returns the asset manager's token
     */
    function getToken() external view returns (IERC20);
    /**
     * @return the current assets under management of this asset manager
     */
    function getAUM(bytes32 poolId) external view returns (uint256);
    /**
     * @return poolCash - The up-to-date cash balance of the pool
     * @return poolManaged - The up-to-date managed balance of the pool
     */
    function getPoolBalances(bytes32 poolId) external view returns (uint256 poolCash, uint256 poolManaged);
    /**
     * @return The difference in tokens between the target investment
     * and the currently invested amount (i.e. the amount that can be invested)
     */
    function maxInvestableBalance(bytes32 poolId) external view returns (int256);
    /**
     * @notice Updates the Vault on the value of the pool's investment returns
     */
    function updateBalanceOfPool(bytes32 poolId) external;
    /**
     * @notice Determines whether the pool should rebalance given the provided balances
     */
    function shouldRebalance(uint256 cash, uint256 managed) external view returns (bool);
    /**
     * @notice Rebalances funds between the pool and the asset manager to maintain target investment percentage.
     * @param poolId - the poolId of the pool to be rebalanced
     * @param force - a boolean representing whether a rebalance should be forced even when the pool is near balance
     */
    function rebalance(bytes32 poolId, bool force) external;
    /**
     * @notice allows an authorized rebalancer to remove capital to facilitate large withdrawals
     * @param poolId - the poolId of the pool to withdraw funds back to
     * @param amount - the amount of tokens to withdraw back to the pool
     */
    function capitalOut(bytes32 poolId, uint256 amount) external;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "../solidity-utils/openzeppelin/IERC20.sol";
interface IControlledPool {
    function setSwapFeePercentage(uint256 swapFeePercentage) external;
    function setAssetManagerPoolConfig(IERC20 token, bytes memory poolConfig) external;
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "../math/Math.sol";
/**
 * @dev Library for encoding and decoding values stored inside a 256 bit word. Typically used to pack multiple values in
 * a single storage slot, saving gas by performing less storage accesses.
 *
 * Each value is defined by its size and the least significant bit in the word, also known as offset. For example, two
 * 128 bit values may be encoded in a word by assigning one an offset of 0, and the other an offset of 128.
 *
 * We could use Solidity structs to pack values together in a single storage slot instead of relying on a custom and
 * error-prone library, but unfortunately Solidity only allows for structs to live in either storage, calldata or
 * memory. Because a memory struct uses not just memory but also a slot in the stack (to store its memory location),
 * using memory for word-sized values (i.e. of 256 bits or less) is strictly less gas performant, and doesn't even
 * prevent stack-too-deep issues. This is compounded by the fact that Balancer contracts typically are memory-intensive,
 * and the cost of accesing memory increases quadratically with the number of allocated words. Manual packing and
 * unpacking is therefore the preferred approach.
 */
library WordCodec {
    // Masks are values with the least significant N bits set. They can be used to extract an encoded value from a word,
    // or to insert a new one replacing the old.
    uint256 private constant _MASK_1 = 2**(1) - 1;
    uint256 private constant _MASK_192 = 2**(192) - 1;
    // In-place insertion
    /**
     * @dev Inserts an unsigned integer of bitLength, shifted by an offset, into a 256 bit word,
     * replacing the old value. Returns the new word.
     */
    function insertUint(
        bytes32 word,
        uint256 value,
        uint256 offset,
        uint256 bitLength
    ) internal pure returns (bytes32) {
        _validateEncodingParams(value, offset, bitLength);
        uint256 mask = (1 << bitLength) - 1;
        bytes32 clearedWord = bytes32(uint256(word) & ~(mask << offset));
        return clearedWord | bytes32(value << offset);
    }
    /**
     * @dev Inserts a signed integer shifted by an offset into a 256 bit word, replacing the old value. Returns
     * the new word.
     *
     * Assumes `value` can be represented using `bitLength` bits.
     */
    function insertInt(
        bytes32 word,
        int256 value,
        uint256 offset,
        uint256 bitLength
    ) internal pure returns (bytes32) {
        _validateEncodingParams(value, offset, bitLength);
        uint256 mask = (1 << bitLength) - 1;
        bytes32 clearedWord = bytes32(uint256(word) & ~(mask << offset));
        // Integer values need masking to remove the upper bits of negative values.
        return clearedWord | bytes32((uint256(value) & mask) << offset);
    }
    // Encoding
    /**
     * @dev Encodes an unsigned integer shifted by an offset. Ensures value fits within
     * `bitLength` bits.
     *
     * The return value can be ORed bitwise with other encoded values to form a 256 bit word.
     */
    function encodeUint(
        uint256 value,
        uint256 offset,
        uint256 bitLength
    ) internal pure returns (bytes32) {
        _validateEncodingParams(value, offset, bitLength);
        return bytes32(value << offset);
    }
    /**
     * @dev Encodes a signed integer shifted by an offset.
     *
     * The return value can be ORed bitwise with other encoded values to form a 256 bit word.
     */
    function encodeInt(
        int256 value,
        uint256 offset,
        uint256 bitLength
    ) internal pure returns (bytes32) {
        _validateEncodingParams(value, offset, bitLength);
        uint256 mask = (1 << bitLength) - 1;
        // Integer values need masking to remove the upper bits of negative values.
        return bytes32((uint256(value) & mask) << offset);
    }
    // Decoding
    /**
     * @dev Decodes and returns an unsigned integer with `bitLength` bits, shifted by an offset, from a 256 bit word.
     */
    function decodeUint(
        bytes32 word,
        uint256 offset,
        uint256 bitLength
    ) internal pure returns (uint256) {
        return uint256(word >> offset) & ((1 << bitLength) - 1);
    }
    /**
     * @dev Decodes and returns a signed integer with `bitLength` bits, shifted by an offset, from a 256 bit word.
     */
    function decodeInt(
        bytes32 word,
        uint256 offset,
        uint256 bitLength
    ) internal pure returns (int256) {
        int256 maxInt = int256((1 << (bitLength - 1)) - 1);
        uint256 mask = (1 << bitLength) - 1;
        int256 value = int256(uint256(word >> offset) & mask);
        // In case the decoded value is greater than the max positive integer that can be represented with bitLength
        // bits, we know it was originally a negative integer. Therefore, we mask it to restore the sign in the 256 bit
        // representation.
        return value > maxInt ? (value | int256(~mask)) : value;
    }
    // Special cases
    /**
     * @dev Decodes and returns a boolean shifted by an offset from a 256 bit word.
     */
    function decodeBool(bytes32 word, uint256 offset) internal pure returns (bool) {
        return (uint256(word >> offset) & _MASK_1) == 1;
    }
    /**
     * @dev Inserts a 192 bit value shifted by an offset into a 256 bit word, replacing the old value.
     * Returns the new word.
     *
     * Assumes `value` can be represented using 192 bits.
     */
    function insertBits192(
        bytes32 word,
        bytes32 value,
        uint256 offset
    ) internal pure returns (bytes32) {
        bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_192 << offset));
        return clearedWord | bytes32((uint256(value) & _MASK_192) << offset);
    }
    /**
     * @dev Inserts a boolean value shifted by an offset into a 256 bit word, replacing the old value. Returns the new
     * word.
     */
    function insertBool(
        bytes32 word,
        bool value,
        uint256 offset
    ) internal pure returns (bytes32) {
        bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_1 << offset));
        return clearedWord | bytes32(uint256(value ? 1 : 0) << offset);
    }
    // Helpers
    function _validateEncodingParams(
        uint256 value,
        uint256 offset,
        uint256 bitLength
    ) private pure {
        _require(offset < 256, Errors.OUT_OF_BOUNDS);
        // We never accept 256 bit values (which would make the codec pointless), and the larger the offset the smaller
        // the maximum bit length.
        _require(bitLength >= 1 && bitLength <= Math.min(255, 256 - offset), Errors.OUT_OF_BOUNDS);
        // Testing unsigned values for size is straightforward: their upper bits must be cleared.
        _require(value >> bitLength == 0, Errors.CODEC_OVERFLOW);
    }
    function _validateEncodingParams(
        int256 value,
        uint256 offset,
        uint256 bitLength
    ) private pure {
        _require(offset < 256, Errors.OUT_OF_BOUNDS);
        // We never accept 256 bit values (which would make the codec pointless), and the larger the offset the smaller
        // the maximum bit length.
        _require(bitLength >= 1 && bitLength <= Math.min(255, 256 - offset), Errors.OUT_OF_BOUNDS);
        // Testing signed values for size is a bit more involved.
        if (value >= 0) {
            // For positive values, we can simply check that the upper bits are clear. Notice we remove one bit from the
            // length for the sign bit.
            _require(value >> (bitLength - 1) == 0, Errors.CODEC_OVERFLOW);
        } else {
            // Negative values can receive the same treatment by making them positive, with the caveat that the range
            // for negative values in two's complement supports one more value than for the positive case.
            _require(Math.abs(value + 1) >> (bitLength - 1) == 0, Errors.CODEC_OVERFLOW);
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ITemporarilyPausable.sol";
/**
 * @dev Allows for a contract to be paused during an initial period after deployment, disabling functionality. Can be
 * used as an emergency switch in case a security vulnerability or threat is identified.
 *
 * The contract can only be paused during the Pause Window, a period that starts at deployment. It can also be
 * unpaused and repaused any number of times during this period. This is intended to serve as a safety measure: it lets
 * system managers react quickly to potentially dangerous situations, knowing that this action is reversible if careful
 * analysis later determines there was a false alarm.
 *
 * If the contract is paused when the Pause Window finishes, it will remain in the paused state through an additional
 * Buffer Period, after which it will be automatically unpaused forever. This is to ensure there is always enough time
 * to react to an emergency, even if the threat is discovered shortly before the Pause Window expires.
 *
 * Note that since the contract can only be paused within the Pause Window, unpausing during the Buffer Period is
 * irreversible.
 */
abstract contract TemporarilyPausable is ITemporarilyPausable {
    // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
    // solhint-disable not-rely-on-time
    uint256 private constant _MAX_PAUSE_WINDOW_DURATION = 90 days;
    uint256 private constant _MAX_BUFFER_PERIOD_DURATION = 30 days;
    uint256 private immutable _pauseWindowEndTime;
    uint256 private immutable _bufferPeriodEndTime;
    bool private _paused;
    constructor(uint256 pauseWindowDuration, uint256 bufferPeriodDuration) {
        _require(pauseWindowDuration <= _MAX_PAUSE_WINDOW_DURATION, Errors.MAX_PAUSE_WINDOW_DURATION);
        _require(bufferPeriodDuration <= _MAX_BUFFER_PERIOD_DURATION, Errors.MAX_BUFFER_PERIOD_DURATION);
        uint256 pauseWindowEndTime = block.timestamp + pauseWindowDuration;
        _pauseWindowEndTime = pauseWindowEndTime;
        _bufferPeriodEndTime = pauseWindowEndTime + bufferPeriodDuration;
    }
    /**
     * @dev Reverts if the contract is paused.
     */
    modifier whenNotPaused() {
        _ensureNotPaused();
        _;
    }
    /**
     * @dev Returns the current contract pause status, as well as the end times of the Pause Window and Buffer
     * Period.
     */
    function getPausedState()
        external
        view
        override
        returns (
            bool paused,
            uint256 pauseWindowEndTime,
            uint256 bufferPeriodEndTime
        )
    {
        paused = !_isNotPaused();
        pauseWindowEndTime = _getPauseWindowEndTime();
        bufferPeriodEndTime = _getBufferPeriodEndTime();
    }
    /**
     * @dev Sets the pause state to `paused`. The contract can only be paused until the end of the Pause Window, and
     * unpaused until the end of the Buffer Period.
     *
     * Once the Buffer Period expires, this function reverts unconditionally.
     */
    function _setPaused(bool paused) internal {
        if (paused) {
            _require(block.timestamp < _getPauseWindowEndTime(), Errors.PAUSE_WINDOW_EXPIRED);
        } else {
            _require(block.timestamp < _getBufferPeriodEndTime(), Errors.BUFFER_PERIOD_EXPIRED);
        }
        _paused = paused;
        emit PausedStateChanged(paused);
    }
    /**
     * @dev Reverts if the contract is paused.
     */
    function _ensureNotPaused() internal view {
        _require(_isNotPaused(), Errors.PAUSED);
    }
    /**
     * @dev Reverts if the contract is not paused.
     */
    function _ensurePaused() internal view {
        _require(!_isNotPaused(), Errors.NOT_PAUSED);
    }
    /**
     * @dev Returns true if the contract is unpaused.
     *
     * Once the Buffer Period expires, the gas cost of calling this function is reduced dramatically, as storage is no
     * longer accessed.
     */
    function _isNotPaused() internal view returns (bool) {
        // After the Buffer Period, the (inexpensive) timestamp check short-circuits the storage access.
        return block.timestamp > _getBufferPeriodEndTime() || !_paused;
    }
    // These getters lead to reduced bytecode size by inlining the immutable variables in a single place.
    function _getPauseWindowEndTime() private view returns (uint256) {
        return _pauseWindowEndTime;
    }
    function _getBufferPeriodEndTime() private view returns (uint256) {
        return _bufferPeriodEndTime;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20.sol";
import "./SafeMath.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is IERC20 {
    using SafeMath for uint256;
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }
    /**
     * @dev See {IERC20-totalSupply}. The total supply should only be read using this function
     *
     * Can be overridden by derived contracts to store the total supply in a different way (e.g. packed with other
     * storage values).
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev Sets a new value for the total supply. It should only be set using this function.
     *
     * * Can be overridden by derived contracts to store the total supply in a different way (e.g. packed with other
     * storage values).
     */
    function _setTotalSupply(uint256 value) internal virtual {
        _totalSupply = value;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(msg.sender, recipient, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(msg.sender, spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(
            sender,
            msg.sender,
            _allowances[sender][msg.sender].sub(amount, Errors.ERC20_TRANSFER_EXCEEDS_ALLOWANCE)
        );
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(
            msg.sender,
            spender,
            _allowances[msg.sender][spender].sub(subtractedValue, Errors.ERC20_DECREASED_ALLOWANCE_BELOW_ZERO)
        );
        return true;
    }
    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        _require(sender != address(0), Errors.ERC20_TRANSFER_FROM_ZERO_ADDRESS);
        _require(recipient != address(0), Errors.ERC20_TRANSFER_TO_ZERO_ADDRESS);
        _beforeTokenTransfer(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount, Errors.ERC20_TRANSFER_EXCEEDS_BALANCE);
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        _beforeTokenTransfer(address(0), account, amount);
        _setTotalSupply(totalSupply().add(amount));
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        _require(account != address(0), Errors.ERC20_BURN_FROM_ZERO_ADDRESS);
        _beforeTokenTransfer(account, address(0), amount);
        _balances[account] = _balances[account].sub(amount, Errors.ERC20_BURN_EXCEEDS_BALANCE);
        _setTotalSupply(totalSupply().sub(amount));
        emit Transfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal {
        _decimals = decimals_;
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        // solhint-disable-previous-line no-empty-blocks
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/vault/IVault.sol";
import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20Permit.sol";
/**
 * @title Highly opinionated token implementation
 * @author Balancer Labs
 * @dev
 * - Includes functions to increase and decrease allowance as a workaround
 *   for the well-known issue with `approve`:
 *   https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
 * - Allows for 'infinite allowance', where an allowance of 0xff..ff is not
 *   decreased by calls to transferFrom
 * - Lets a token holder use `transferFrom` to send their own tokens,
 *   without first setting allowance
 * - Emits 'Approval' events whenever allowance is changed by `transferFrom`
 * - Assigns infinite allowance for all token holders to the Vault
 */
contract BalancerPoolToken is ERC20Permit {
    IVault private immutable _vault;
    constructor(
        string memory tokenName,
        string memory tokenSymbol,
        IVault vault
    ) ERC20(tokenName, tokenSymbol) ERC20Permit(tokenName) {
        _vault = vault;
    }
    function getVault() public view returns (IVault) {
        return _vault;
    }
    // Overrides
    /**
     * @dev Override to grant the Vault infinite allowance, causing for Pool Tokens to not require approval.
     *
     * This is sound as the Vault already provides authorization mechanisms when initiation token transfers, which this
     * contract inherits.
     */
    function allowance(address owner, address spender) public view override returns (uint256) {
        if (spender == address(getVault())) {
            return uint256(-1);
        } else {
            return super.allowance(owner, spender);
        }
    }
    /**
     * @dev Override to allow for 'infinite allowance' and let the token owner use `transferFrom` with no self-allowance
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public override returns (bool) {
        uint256 currentAllowance = allowance(sender, msg.sender);
        _require(msg.sender == sender || currentAllowance >= amount, Errors.ERC20_TRANSFER_EXCEEDS_ALLOWANCE);
        _transfer(sender, recipient, amount);
        if (msg.sender != sender && currentAllowance != uint256(-1)) {
            // Because of the previous require, we know that if msg.sender != sender then currentAllowance >= amount
            _approve(sender, msg.sender, currentAllowance - amount);
        }
        return true;
    }
    /**
     * @dev Override to allow decreasing allowance by more than the current amount (setting it to zero)
     */
    function decreaseAllowance(address spender, uint256 amount) public override returns (bool) {
        uint256 currentAllowance = allowance(msg.sender, spender);
        if (amount >= currentAllowance) {
            _approve(msg.sender, spender, 0);
        } else {
            // No risk of underflow due to if condition
            _approve(msg.sender, spender, currentAllowance - amount);
        }
        return true;
    }
    // Internal functions
    function _mintPoolTokens(address recipient, uint256 amount) internal {
        _mint(recipient, amount);
    }
    function _burnPoolTokens(address sender, uint256 amount) internal {
        _burn(sender, amount);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/vault/IAuthorizer.sol";
import "@balancer-labs/v2-solidity-utils/contracts/helpers/Authentication.sol";
/**
 * @dev Base authorization layer implementation for Pools.
 *
 * The owner account can call some of the permissioned functions - access control of the rest is delegated to the
 * Authorizer. Note that this owner is immutable: more sophisticated permission schemes, such as multiple ownership,
 * granular roles, etc., could be built on top of this by making the owner a smart contract.
 *
 * Access control of all other permissioned functions is delegated to an Authorizer. It is also possible to delegate
 * control of *all* permissioned functions to the Authorizer by setting the owner address to `_DELEGATE_OWNER`.
 */
abstract contract BasePoolAuthorization is Authentication {
    address private immutable _owner;
    address private constant _DELEGATE_OWNER = 0xBA1BA1ba1BA1bA1bA1Ba1BA1ba1BA1bA1ba1ba1B;
    constructor(address owner) {
        _owner = owner;
    }
    function getOwner() public view returns (address) {
        return _owner;
    }
    function getAuthorizer() external view returns (IAuthorizer) {
        return _getAuthorizer();
    }
    function _canPerform(bytes32 actionId, address account) internal view override returns (bool) {
        if ((getOwner() != _DELEGATE_OWNER) && _isOwnerOnlyAction(actionId)) {
            // Only the owner can perform "owner only" actions, unless the owner is delegated.
            return msg.sender == getOwner();
        } else {
            // Non-owner actions are always processed via the Authorizer, as "owner only" ones are when delegated.
            return _getAuthorizer().canPerform(actionId, account, address(this));
        }
    }
    function _isOwnerOnlyAction(bytes32) internal view virtual returns (bool) {
        return false;
    }
    function _getAuthorizer() internal view virtual returns (IAuthorizer);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/BasePoolUserData.sol";
import "@balancer-labs/v2-interfaces/contracts/pool-utils/IRecoveryMode.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "./BasePoolAuthorization.sol";
/**
 * @notice Handle storage and state changes for pools that support "Recovery Mode".
 *
 * @dev This is intended to provide a safe way to exit any pool during some kind of emergency, to avoid locking funds
 * in the event the pool enters a non-functional state (i.e., some code that normally runs during exits is causing
 * them to revert).
 *
 * Recovery Mode is *not* the same as pausing the pool. The pause function is only available during a short window
 * after factory deployment. Pausing can only be intentionally reversed during a buffer period, and the contract
 * will permanently unpause itself thereafter. Paused pools are completely disabled, in a kind of suspended animation,
 * until they are voluntarily or involuntarily unpaused.
 *
 * By contrast, a privileged account - typically a governance multisig - can place a pool in Recovery Mode at any
 * time, and it is always reversible. The pool is *not* disabled while in this mode: though of course whatever
 * condition prompted the transition to Recovery Mode has likely effectively disabled some functions. Rather,
 * a special "clean" exit is enabled, which runs the absolute minimum code necessary to exit proportionally.
 * In particular, stable pools do not attempt to compute the invariant (which is a complex, iterative calculation
 * that can fail in extreme circumstances), and no protocol fees are collected.
 *
 * It is critical to ensure that turning on Recovery Mode would do no harm, if activated maliciously or in error.
 */
abstract contract RecoveryMode is IRecoveryMode, BasePoolAuthorization {
    using FixedPoint for uint256;
    using BasePoolUserData for bytes;
    /**
     * @dev Reverts if the contract is in Recovery Mode.
     */
    modifier whenNotInRecoveryMode() {
        _ensureNotInRecoveryMode();
        _;
    }
    /**
     * @notice Enable recovery mode, which enables a special safe exit path for LPs.
     * @dev Does not otherwise affect pool operations (beyond deferring payment of protocol fees), though some pools may
     * perform certain operations in a "safer" manner that is less likely to fail, in an attempt to keep the pool
     * running, even in a pathological state. Unlike the Pause operation, which is only available during a short window
     * after factory deployment, Recovery Mode can always be enabled.
     */
    function enableRecoveryMode() external override authenticate {
        _setRecoveryMode(true);
    }
    /**
     * @notice Disable recovery mode, which disables the special safe exit path for LPs.
     * @dev Protocol fees are not paid while in Recovery Mode, so it should only remain active for as long as strictly
     * necessary.
     *
     * This function will revert when called within a Vault context (i.e. in the middle of a join or an exit).
     *
     * This function depends on the invariant value, which may be calculated incorrectly in the middle of a join or
     * an exit, because the state of the pool could be out of sync with the state of the Vault.
     * `_onDisableRecoveryMode` will revert when called from such a context for composable stable pools, effectively
     * protecting this function.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    function disableRecoveryMode() external override authenticate {
        _setRecoveryMode(false);
    }
    // Defer implementation for functions that require storage
    /**
     * @notice Override to check storage and return whether the pool is in Recovery Mode
     */
    function inRecoveryMode() public view virtual override returns (bool);
    /**
     * @dev Override to update storage and emit the event
     *
     * No complex code or external calls that could fail should be placed in the implementations,
     * which could jeopardize the ability to enable and disable Recovery Mode.
     */
    function _setRecoveryMode(bool enabled) internal virtual;
    /**
     * @dev Reverts if the contract is not in Recovery Mode.
     */
    function _ensureInRecoveryMode() internal view {
        _require(inRecoveryMode(), Errors.NOT_IN_RECOVERY_MODE);
    }
    /**
     * @dev Reverts if the contract is in Recovery Mode.
     */
    function _ensureNotInRecoveryMode() internal view {
        _require(!inRecoveryMode(), Errors.IN_RECOVERY_MODE);
    }
    /**
     * @dev A minimal proportional exit, suitable as is for most pools: though not for pools with preminted BPT
     * or other special considerations. Designed to be overridden if a pool needs to do extra processing,
     * such as scaling a stored invariant, or caching the new total supply.
     *
     * No complex code or external calls should be made in derived contracts that override this!
     */
    function _doRecoveryModeExit(
        uint256[] memory balances,
        uint256 totalSupply,
        bytes memory userData
    ) internal virtual returns (uint256, uint256[] memory) {
        uint256 bptAmountIn = userData.recoveryModeExit();
        uint256[] memory amountsOut = _computeProportionalAmountsOut(balances, totalSupply, bptAmountIn);
        return (bptAmountIn, amountsOut);
    }
    function _computeProportionalAmountsOut(
        uint256[] memory balances,
        uint256 totalSupply,
        uint256 bptAmountIn
    ) internal pure returns (uint256[] memory amountsOut) {
        /**********************************************************************************************
        // exactBPTInForTokensOut                                                                    //
        // (per token)                                                                               //
        // aO = tokenAmountOut             /        bptIn         \\                                  //
        // b = tokenBalance      a0 = b * | ---------------------  |                                 //
        // bptIn = bptAmountIn             \\     bptTotalSupply    /                                 //
        // bpt = bptTotalSupply                                                                      //
        **********************************************************************************************/
        // Since we're computing an amount out, we round down overall. This means rounding down on both the
        // multiplication and division.
        uint256 bptRatio = bptAmountIn.divDown(totalSupply);
        amountsOut = new uint256[](balances.length);
        for (uint256 i = 0; i < balances.length; i++) {
            amountsOut[i] = balances[i].mulDown(bptRatio);
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        _require(c >= a, Errors.ADD_OVERFLOW);
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, Errors.SUB_OVERFLOW);
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        uint256 errorCode
    ) internal pure returns (uint256) {
        _require(b <= a, errorCode);
        uint256 c = a - b;
        return c;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/openzeppelin/IERC20Permit.sol";
import "./ERC20.sol";
import "../helpers/EOASignaturesValidator.sol";
/**
 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * _Available since v3.4._
 */
abstract contract ERC20Permit is ERC20, IERC20Permit, EOASignaturesValidator {
    // solhint-disable-next-line var-name-mixedcase
    bytes32 private constant _PERMIT_TYPEHASH = keccak256(
        "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
    );
    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
     */
    constructor(string memory name) EIP712(name, "1") {
        // solhint-disable-previous-line no-empty-blocks
    }
    /**
     * @dev See {IERC20Permit-permit}.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual override {
        bytes32 structHash = keccak256(
            abi.encode(_PERMIT_TYPEHASH, owner, spender, value, getNextNonce(owner), deadline)
        );
        _ensureValidSignature(owner, structHash, _toArraySignature(v, r, s), deadline, Errors.INVALID_SIGNATURE);
        _approve(owner, spender, value);
    }
    /**
     * @dev See {IERC20Permit-nonces}.
     */
    function nonces(address owner) public view override returns (uint256) {
        return getNextNonce(owner);
    }
    /**
     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
        return getDomainSeparator();
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over `owner`'s tokens,
     * given `owner`'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);
    /**
     * @dev Returns the domain separator used in the encoding of the signature for `permit`, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/ISignaturesValidator.sol";
import "../openzeppelin/EIP712.sol";
/**
 * @dev Utility for signing Solidity function calls.
 */
abstract contract EOASignaturesValidator is ISignaturesValidator, EIP712 {
    // Replay attack prevention for each account.
    mapping(address => uint256) internal _nextNonce;
    function getDomainSeparator() public view override returns (bytes32) {
        return _domainSeparatorV4();
    }
    function getNextNonce(address account) public view override returns (uint256) {
        return _nextNonce[account];
    }
    function _ensureValidSignature(
        address account,
        bytes32 structHash,
        bytes memory signature,
        uint256 errorCode
    ) internal {
        return _ensureValidSignature(account, structHash, signature, type(uint256).max, errorCode);
    }
    function _ensureValidSignature(
        address account,
        bytes32 structHash,
        bytes memory signature,
        uint256 deadline,
        uint256 errorCode
    ) internal {
        bytes32 digest = _hashTypedDataV4(structHash);
        _require(_isValidSignature(account, digest, signature), errorCode);
        // We could check for the deadline before validating the signature, but this leads to saner error processing (as
        // we only care about expired deadlines if the signature is correct) and only affects the gas cost of the revert
        // scenario, which will only occur infrequently, if ever.
        // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
        // solhint-disable-next-line not-rely-on-time
        _require(deadline >= block.timestamp, Errors.EXPIRED_SIGNATURE);
        // We only advance the nonce after validating the signature. This is irrelevant for this module, but it can be
        // important in derived contracts that override _isValidSignature (e.g. SignaturesValidator), as we want for
        // the observable state to still have the current nonce as the next valid one.
        _nextNonce[account] += 1;
    }
    function _isValidSignature(
        address account,
        bytes32 digest,
        bytes memory signature
    ) internal view virtual returns (bool) {
        _require(signature.length == 65, Errors.MALFORMED_SIGNATURE);
        bytes32 r;
        bytes32 s;
        uint8 v;
        // ecrecover takes the r, s and v signature parameters, and the only way to get them is to use assembly.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }
        address recoveredAddress = ecrecover(digest, v, r, s);
        // ecrecover returns the zero address on recover failure, so we need to handle that explicitly.
        return (recoveredAddress != address(0) && recoveredAddress == account);
    }
    function _toArraySignature(
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (bytes memory) {
        bytes memory signature = new bytes(65);
        // solhint-disable-next-line no-inline-assembly
        assembly {
            mstore(add(signature, 32), r)
            mstore(add(signature, 64), s)
            mstore8(add(signature, 96), v)
        }
        return signature;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;
    /* solhint-enable var-name-mixedcase */
    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        _HASHED_NAME = keccak256(bytes(name));
        _HASHED_VERSION = keccak256(bytes(version));
        _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
    }
    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view virtual returns (bytes32) {
        return keccak256(abi.encode(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION, _getChainId(), address(this)));
    }
    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return keccak256(abi.encodePacked("\\x19\\x01", _domainSeparatorV4(), structHash));
    }
    function _getChainId() private view returns (uint256 chainId) {
        // Silence state mutability warning without generating bytecode.
        // See https://github.com/ethereum/solidity/issues/10090#issuecomment-741789128 and
        // https://github.com/ethereum/solidity/issues/2691
        this;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            chainId := chainid()
        }
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
library BasePoolUserData {
    // Special ExitKind for all pools, used in Recovery Mode. Use the max 8-bit value to prevent conflicts
    // with future additions to the ExitKind enums (or any front-end code that maps to existing values)
    uint8 public constant RECOVERY_MODE_EXIT_KIND = 255;
    // Return true if this is the special exit kind.
    function isRecoveryModeExitKind(bytes memory self) internal pure returns (bool) {
        // Check for the "no data" case, or abi.decode would revert
        return self.length > 0 && abi.decode(self, (uint8)) == RECOVERY_MODE_EXIT_KIND;
    }
    // Parse the bptAmountIn out of the userData
    function recoveryModeExit(bytes memory self) internal pure returns (uint256 bptAmountIn) {
        (, bptAmountIn) = abi.decode(self, (uint8, uint256));
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
/**
 * @dev Interface for the RecoveryMode module.
 */
interface IRecoveryMode {
    /**
     * @dev Emitted when the Recovery Mode status changes.
     */
    event RecoveryModeStateChanged(bool enabled);
    /**
     * @notice Enables Recovery Mode in the Pool, disabling protocol fee collection and allowing for safe proportional
     * exits with low computational complexity and no dependencies.
     */
    function enableRecoveryMode() external;
    /**
     * @notice Disables Recovery Mode in the Pool, restoring protocol fee collection and disallowing proportional exits.
     */
    function disableRecoveryMode() external;
    /**
     * @notice Returns true if the Pool is in Recovery Mode.
     */
    function inRecoveryMode() external view returns (bool);
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
import "@balancer-labs/v2-interfaces/contracts/standalone-utils/IProtocolFeePercentagesProvider.sol";
import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/SafeCast.sol";
import "../RecoveryMode.sol";
/**
 * @dev The Vault does not provide the protocol swap fee percentage in swap hooks (as swaps don't typically need this
 * value), so for swaps that need this value, we would have to to fetch it ourselves from the
 * ProtocolFeePercentagesProvider. Additionally, other protocol fee types (such as Yield or AUM) can only be obtained
 * by making said call.
 *
 * However, these values change so rarely that it doesn't make sense to perform the required calls to get the current
 * values in every single user interaction. Instead, we keep a local copy that can be permissionlessly updated by anyone
 * with the real value. We also pack these values together, performing a single storage read to get them all.
 *
 * When initialized with a special sentinel value, the swap fee is delegated, meaning the mutable protocol swap fee
 * cache is set to the current value stored in the ProtocolFeePercentagesProvider, and can be updated by anyone with a
 * call to `updateProtocolFeePercentageCache`. Any other value means the protocol swap fee is fixed, so it is instead
 * stored in the immutable `_fixedProtocolSwapFeePercentage`.
 */
abstract contract ProtocolFeeCache is RecoveryMode {
    using SafeCast for uint256;
    IProtocolFeePercentagesProvider private immutable _protocolFeeProvider;
    // Protocol Fee Percentages can never be larger than 100% (1e18), which fits in ~59 bits, so using 64 for each type
    // is sufficient.
    struct FeeTypeCache {
        uint64 swapFee;
        uint64 yieldFee;
        uint64 aumFee;
    }
    FeeTypeCache private _cache;
    event ProtocolFeePercentageCacheUpdated(uint256 indexed feeType, uint256 protocolFeePercentage);
    // Swap fees can be set to a fixed value at construction, or delegated to the ProtocolFeePercentagesProvider if
    // passing the special sentinel value.
    uint256 public constant DELEGATE_PROTOCOL_SWAP_FEES_SENTINEL = type(uint256).max;
    bool private immutable _delegatedProtocolSwapFees;
    // Only valid when `_delegatedProtocolSwapFees` is false
    uint256 private immutable _fixedProtocolSwapFeePercentage;
    constructor(IProtocolFeePercentagesProvider protocolFeeProvider, uint256 protocolSwapFeePercentage) {
        // Protocol swap fees are delegated to the value reported by the ProtocolFeePercentagesProvider if the sentinel
        // value is passed.
        bool delegatedProtocolSwapFees = protocolSwapFeePercentage == DELEGATE_PROTOCOL_SWAP_FEES_SENTINEL;
        _delegatedProtocolSwapFees = delegatedProtocolSwapFees;
        _protocolFeeProvider = protocolFeeProvider;
        _updateProtocolFeeCache(protocolFeeProvider, ProtocolFeeType.YIELD);
        _updateProtocolFeeCache(protocolFeeProvider, ProtocolFeeType.AUM);
        if (delegatedProtocolSwapFees) {
            _updateProtocolFeeCache(protocolFeeProvider, ProtocolFeeType.SWAP);
        } else {
            _require(
                protocolSwapFeePercentage <= protocolFeeProvider.getFeeTypeMaximumPercentage(ProtocolFeeType.SWAP),
                Errors.SWAP_FEE_PERCENTAGE_TOO_HIGH
            );
            // We cannot set `_fixedProtocolSwapFeePercentage` here due to it being immutable so instead we must set it
            // in the main function scope with a value based on whether protocol fees are delegated.
            // Emit an event as we do in `_updateProtocolFeeCache` to appear the same to offchain indexers.
            emit ProtocolFeePercentageCacheUpdated(ProtocolFeeType.SWAP, protocolSwapFeePercentage);
        }
        // As `_fixedProtocolSwapFeePercentage` is immutable we must set a value, but just set to zero if it's not used.
        _fixedProtocolSwapFeePercentage = delegatedProtocolSwapFees ? 0 : protocolSwapFeePercentage;
    }
    /**
     * @dev Returns the cached protocol fee percentage. If `getProtocolSwapFeeDelegation()` is false, this value is
     * immutable for swap fee queries. Alternatively, it will track the global fee percentage set in the
     * ProtocolFeePercentagesProvider.
     */
    function getProtocolFeePercentageCache(uint256 feeType) public view returns (uint256) {
        if (inRecoveryMode()) {
            return 0;
        }
        if (feeType == ProtocolFeeType.SWAP) {
            return getProtocolSwapFeeDelegation() ? _cache.swapFee : _fixedProtocolSwapFeePercentage;
        } else if (feeType == ProtocolFeeType.YIELD) {
            return _cache.yieldFee;
        } else if (feeType == ProtocolFeeType.AUM) {
            return _cache.aumFee;
        } else {
            _revert(Errors.UNHANDLED_FEE_TYPE);
        }
    }
    /**
     * @dev Can be called by anyone to update the cached fee percentages (swap fee is only updated when delegated).
     * Updates the cache to the latest value set by governance.
     *
     * This function will revert when called within a Vault context (i.e. in the middle of a join or an exit).
     *
     * This function depends on the invariant value, which may be calculated incorrectly in the middle of a join or
     * an exit, because the state of the pool could be out of sync with the state of the Vault.
     * `_beforeProtocolFeeCacheUpdate` will revert when called from such a context for composable stable pools,
     * effectively protecting this function.
     *
     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
     */
    function updateProtocolFeePercentageCache() external {
        _beforeProtocolFeeCacheUpdate();
        if (getProtocolSwapFeeDelegation()) {
            _updateProtocolFeeCache(_protocolFeeProvider, ProtocolFeeType.SWAP);
        }
        _updateProtocolFeeCache(_protocolFeeProvider, ProtocolFeeType.YIELD);
        _updateProtocolFeeCache(_protocolFeeProvider, ProtocolFeeType.AUM);
    }
    /**
     * @dev Override in derived contracts to perform some action before the cache is updated. This is typically relevant
     * to Pools that incur protocol debt between operations. To avoid altering the amount due retroactively, this debt
     * needs to be paid before the fee percentages change.
     */
    function _beforeProtocolFeeCacheUpdate() internal virtual {}
    /**
     * @dev Returns whether this Pool tracks protocol swap fee changes in the IProtocolFeePercentagesProvider.
     */
    function getProtocolSwapFeeDelegation() public view returns (bool) {
        return _delegatedProtocolSwapFees;
    }
    function _updateProtocolFeeCache(IProtocolFeePercentagesProvider protocolFeeProvider, uint256 feeType) private {
        uint256 currentValue = protocolFeeProvider.getFeeTypePercentage(feeType);
        if (feeType == ProtocolFeeType.SWAP) {
            _cache.swapFee = currentValue.toUint64();
        } else if (feeType == ProtocolFeeType.YIELD) {
            _cache.yieldFee = currentValue.toUint64();
        } else if (feeType == ProtocolFeeType.AUM) {
            _cache.aumFee = currentValue.toUint64();
        } else {
            _revert(Errors.UNHANDLED_FEE_TYPE);
        }
        emit ProtocolFeePercentageCacheUpdated(feeType, currentValue);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
import "./ProtocolFees.sol";
library InvariantGrowthProtocolSwapFees {
    using FixedPoint for uint256;
    function getProtocolOwnershipPercentage(
        uint256 invariantGrowthRatio,
        uint256 supplyGrowthRatio,
        uint256 protocolSwapFeePercentage
    ) internal pure returns (uint256) {
        // Joins and exits are symmetrical; for simplicity, we consider a join, where the invariant and supply
        // both increase.
        // |-------------------------|-- original invariant * invariantGrowthRatio
        // |   increase from fees    |
        // |-------------------------|-- original invariant * supply growth ratio (fee-less invariant)
        // |                         |
        // | increase from balances  |
        // |-------------------------|-- original invariant
        // |                         |
        // |                         |  |------------------|-- currentSupply
        // |                         |  |    BPT minted    |
        // |                         |  |------------------|-- previousSupply
        // |   original invariant    |  |  original supply |
        // |_________________________|  |__________________|
        //
        // If the join is proportional, the invariant and supply will likewise increase proportionally,
        // so the growth ratios (invariantGrowthRatio / supplyGrowthRatio) will be equal. In this case, we do not charge
        // any protocol fees.
        // We also charge no protocol fees in the case where `invariantGrowthRatio < supplyGrowthRatio` to avoid
        // potential underflows, however this should only occur in extremely low volume actions due solely to rounding
        // error.
        if ((supplyGrowthRatio >= invariantGrowthRatio) || (protocolSwapFeePercentage == 0)) return 0;
        // If the join is non-proportional, the supply increase will be proportionally less than the invariant increase,
        // since the BPT minted will be based on fewer tokens (because swap fees are not included). So the supply growth
        // is due entirely to the balance changes, while the invariant growth also includes swap fees.
        //
        // To isolate the amount of increase by fees then, we multiply the original invariant by the supply growth
        // ratio to get the "feeless invariant". The difference between the final invariant and this value is then
        // the amount of the invariant due to fees, which we convert to a percentage by normalizing against the
        // final invariant. This is expressed as the expression below:
        //
        // invariantGrowthFromFees = currentInvariant - supplyGrowthRatio * previousInvariant
        //
        // We then divide through by current invariant so the LHS can be identified as the fraction of the pool which
        // is made up of accumulated swap fees.
        //
        // swapFeesPercentage = 1 - supplyGrowthRatio * previousInvariant / currentInvariant
        //
        // We then define `invariantGrowthRatio` in a similar fashion to `supplyGrowthRatio` to give the result:
        //
        // swapFeesPercentage = 1 - supplyGrowthRatio / invariantGrowthRatio
        //
        // Using this form allows us to consider only the ratios of the two invariants, rather than their absolute
        // values: a useful property, as this is sometimes easier than calculating the full invariant twice.
        // We've already checked that `supplyGrowthRatio` is smaller than `invariantGrowthRatio`, and hence their ratio
        // smaller than FixedPoint.ONE, allowing for unchecked arithmetic.
        uint256 swapFeesPercentage = FixedPoint.ONE - supplyGrowthRatio.divDown(invariantGrowthRatio);
        // We then multiply by the protocol swap fee percentage to get the fraction of the pool which the protocol
        // should own once fees have been collected.
        return swapFeesPercentage.mulDown(protocolSwapFeePercentage);
    }
    function calcDueProtocolFees(
        uint256 invariantGrowthRatio,
        uint256 previousSupply,
        uint256 currentSupply,
        uint256 protocolSwapFeePercentage
    ) internal pure returns (uint256) {
        uint256 protocolOwnershipPercentage = getProtocolOwnershipPercentage(
            invariantGrowthRatio,
            currentSupply.divDown(previousSupply),
            protocolSwapFeePercentage
        );
        return ProtocolFees.bptForPoolOwnershipPercentage(currentSupply, protocolOwnershipPercentage);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/BalancerErrors.sol";
/**
 * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
 * checks.
 *
 * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
 * easily result in undesired exploitation or bugs, since developers usually
 * assume that overflows raise errors. `SafeCast` restores this intuition by
 * reverting the transaction when such an operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 *
 * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
 * all math on `uint256` and `int256` and then downcasting.
 */
library SafeCast {
    /**
     * @dev Converts an unsigned uint256 into a signed int256.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxInt256.
     */
    function toInt256(uint256 value) internal pure returns (int256) {
        _require(value >> 255 == 0, Errors.SAFE_CAST_VALUE_CANT_FIT_INT256);
        return int256(value);
    }
    /**
     * @dev Converts an unsigned uint256 into an unsigned uint64.
     *
     * Requirements:
     *
     * - input must be less than or equal to maxUint64.
     */
    function toUint64(uint256 value) internal pure returns (uint64) {
        _require(value <= type(uint64).max, Errors.SAFE_CAST_VALUE_CANT_FIT_UINT64);
        return uint64(value);
    }
}
// SPDX-License-Identifier: GPL-3.0-or-later
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
pragma solidity ^0.7.0;
import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
library ProtocolFees {
    using FixedPoint for uint256;
    /**
     * @dev Calculates the amount of BPT necessary to give ownership of a given percentage of the Pool.
     * Note that this function reverts if `poolPercentage` >= 100%, it's expected that the caller will enforce this.
     * @param totalSupply - The total supply of the pool prior to minting BPT.
     * @param poolOwnershipPercentage - The desired ownership percentage of the pool to have as a result of minting BPT.
     * @return bptAmount - The amount of BPT to mint such that it is `poolPercentage` of the resultant total supply.
     */
    function bptForPoolOwnershipPercentage(uint256 totalSupply, uint256 poolOwnershipPercentage)
        internal
        pure
        returns (uint256)
    {
        // If we mint some amount `bptAmount` of BPT then the percentage ownership of the pool this grants is given by:
        // `poolOwnershipPercentage = bptAmount / (totalSupply + bptAmount)`.
        // Solving for `bptAmount`, we arrive at:
        // `bptAmount = totalSupply * poolOwnershipPercentage / (1 - poolOwnershipPercentage)`.
        return Math.divDown(Math.mul(totalSupply, poolOwnershipPercentage), poolOwnershipPercentage.complement());
    }
}