// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
//   $$\\     $$\\       $$\\                 $$\\                         $$\\
//   $$ |    $$ |      \\__|                $$ |                        $$ |
// $$$$$$\\   $$$$$$$\\  $$\\  $$$$$$\\   $$$$$$$ |$$\\  $$\\  $$\\  $$$$$$\\  $$$$$$$\\
// \\_$$  _|  $$  __$$\\ $$ |$$  __$$\\ $$  __$$ |$$ | $$ | $$ |$$  __$$\\ $$  __$$\\
//   $$ |    $$ |  $$ |$$ |$$ |  \\__|$$ /  $$ |$$ | $$ | $$ |$$$$$$$$ |$$ |  $$ |
//   $$ |$$\\ $$ |  $$ |$$ |$$ |      $$ |  $$ |$$ | $$ | $$ |$$   ____|$$ |  $$ |
//   \\$$$$  |$$ |  $$ |$$ |$$ |      \\$$$$$$$ |\\$$$$$\\$$$$  |\\$$$$$$$\\ $$$$$$$  |
//    \\____/ \\__|  \\__|\\__|\\__|       \\_______| \\_____\\____/  \\_______|\\_______/
import "./extension/interface/IContractFactory.sol";
import "@openzeppelin/contracts/metatx/ERC2771Context.sol";
import "@openzeppelin/contracts/utils/Multicall.sol";
import "@openzeppelin/contracts/proxy/Clones.sol";
contract TWCloneFactory is Multicall, ERC2771Context, IContractFactory {
    /// @dev Emitted when a proxy is deployed.
    event ProxyDeployed(address indexed implementation, address proxy, address indexed deployer);
    constructor(address _trustedForwarder) ERC2771Context(_trustedForwarder) {}
    /// @dev Deploys a proxy that points to the given implementation.
    function deployProxyByImplementation(
        address _implementation,
        bytes memory _data,
        bytes32 _salt
    ) public override returns (address deployedProxy) {
        bytes32 salthash = keccak256(abi.encodePacked(_msgSender(), _salt));
        deployedProxy = Clones.cloneDeterministic(_implementation, salthash);
        emit ProxyDeployed(_implementation, deployedProxy, _msgSender());
        if (_data.length > 0) {
            // slither-disable-next-line unused-return
            Address.functionCall(deployedProxy, _data);
        }
    }
    function _msgSender() internal view virtual override returns (address sender) {
        return ERC2771Context._msgSender();
    }
    function _msgData() internal view virtual override returns (bytes calldata) {
        return ERC2771Context._msgData();
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
interface IContractFactory {
    /**
     *  @notice Deploys a proxy that points to that points to the given implementation.
     *
     *  @param implementation           Address of the implementation to point to.
     *
     *  @param data                     Additional data to pass to the proxy constructor or any other data useful during deployement.
     *  @param salt                     Salt to use for the deterministic address generation.
     */
    function deployProxyByImplementation(
        address implementation,
        bytes memory data,
        bytes32 salt
    ) external returns (address);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (metatx/ERC2771Context.sol)
pragma solidity ^0.8.9;
import "../utils/Context.sol";
/**
 * @dev Context variant with ERC2771 support.
 */
abstract contract ERC2771Context is Context {
    /// @custom:oz-upgrades-unsafe-allow state-variable-immutable
    address private immutable _trustedForwarder;
    /// @custom:oz-upgrades-unsafe-allow constructor
    constructor(address trustedForwarder) {
        _trustedForwarder = trustedForwarder;
    }
    function isTrustedForwarder(address forwarder) public view virtual returns (bool) {
        return forwarder == _trustedForwarder;
    }
    function _msgSender() internal view virtual override returns (address sender) {
        if (isTrustedForwarder(msg.sender)) {
            // The assembly code is more direct than the Solidity version using `abi.decode`.
            /// @solidity memory-safe-assembly
            assembly {
                sender := shr(96, calldataload(sub(calldatasize(), 20)))
            }
        } else {
            return super._msgSender();
        }
    }
    function _msgData() internal view virtual override returns (bytes calldata) {
        if (isTrustedForwarder(msg.sender)) {
            return msg.data[:msg.data.length - 20];
        } else {
            return super._msgData();
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (proxy/Clones.sol)
pragma solidity ^0.8.0;
/**
 * @dev https://eips.ethereum.org/EIPS/eip-1167[EIP 1167] is a standard for
 * deploying minimal proxy contracts, also known as "clones".
 *
 * > To simply and cheaply clone contract functionality in an immutable way, this standard specifies
 * > a minimal bytecode implementation that delegates all calls to a known, fixed address.
 *
 * The library includes functions to deploy a proxy using either `create` (traditional deployment) or `create2`
 * (salted deterministic deployment). It also includes functions to predict the addresses of clones deployed using the
 * deterministic method.
 *
 * _Available since v3.4._
 */
library Clones {
    /**
     * @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
     *
     * This function uses the create opcode, which should never revert.
     */
    function clone(address implementation) internal returns (address instance) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
            mstore(add(ptr, 0x14), shl(0x60, implementation))
            mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000)
            instance := create(0, ptr, 0x37)
        }
        require(instance != address(0), "ERC1167: create failed");
    }
    /**
     * @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
     *
     * This function uses the create2 opcode and a `salt` to deterministically deploy
     * the clone. Using the same `implementation` and `salt` multiple time will revert, since
     * the clones cannot be deployed twice at the same address.
     */
    function cloneDeterministic(address implementation, bytes32 salt) internal returns (address instance) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
            mstore(add(ptr, 0x14), shl(0x60, implementation))
            mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000)
            instance := create2(0, ptr, 0x37, salt)
        }
        require(instance != address(0), "ERC1167: create2 failed");
    }
    /**
     * @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
     */
    function predictDeterministicAddress(
        address implementation,
        bytes32 salt,
        address deployer
    ) internal pure returns (address predicted) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
            mstore(add(ptr, 0x14), shl(0x60, implementation))
            mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf3ff00000000000000000000000000000000)
            mstore(add(ptr, 0x38), shl(0x60, deployer))
            mstore(add(ptr, 0x4c), salt)
            mstore(add(ptr, 0x6c), keccak256(ptr, 0x37))
            predicted := keccak256(add(ptr, 0x37), 0x55)
        }
    }
    /**
     * @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
     */
    function predictDeterministicAddress(address implementation, bytes32 salt)
        internal
        view
        returns (address predicted)
    {
        return predictDeterministicAddress(implementation, salt, address(this));
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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
                /// @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 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 v4.5.0) (utils/Multicall.sol)
pragma solidity ^0.8.0;
import "./Address.sol";
/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
abstract contract Multicall {
    /**
     * @dev Receives and executes a batch of function calls on this contract.
     */
    function multicall(bytes[] calldata data) external virtual returns (bytes[] memory results) {
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; i++) {
            results[i] = Address.functionDelegateCall(address(this), data[i]);
        }
        return results;
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20 {
    function totalSupply() external view returns (uint256);
    function balanceOf(address who) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);
    function transfer(address to, uint256 value) external returns (bool);
    function approve(address spender, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/**
 * @title ERC20Metadata interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20Metadata {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./interface/IContractMetadata.sol";
/**
 *  @title   Contract Metadata
 *  @notice  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *           for you contract.
 *           Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */
abstract contract ContractMetadata is IContractMetadata {
    /// @notice Returns the contract metadata URI.
    string public override contractURI;
    /**
     *  @notice         Lets a contract admin set the URI for contract-level metadata.
     *  @dev            Caller should be authorized to setup contractURI, e.g. contract admin.
     *                  See {_canSetContractURI}.
     *                  Emits {ContractURIUpdated Event}.
     *
     *  @param _uri     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function setContractURI(string memory _uri) external override {
        if (!_canSetContractURI()) {
            revert("Not authorized");
        }
        _setupContractURI(_uri);
    }
    /// @dev Lets a contract admin set the URI for contract-level metadata.
    function _setupContractURI(string memory _uri) internal {
        string memory prevURI = contractURI;
        contractURI = _uri;
        emit ContractURIUpdated(prevURI, _uri);
    }
    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual returns (bool);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./interface/IPermissions.sol";
import "../lib/TWStrings.sol";
/**
 *  @title   Permissions
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms
 */
contract Permissions is IPermissions {
    /// @dev Map from keccak256 hash of a role => a map from address => whether address has role.
    mapping(bytes32 => mapping(address => bool)) private _hasRole;
    /// @dev Map from keccak256 hash of a role to role admin. See {getRoleAdmin}.
    mapping(bytes32 => bytes32) private _getRoleAdmin;
    /// @dev Default admin role for all roles. Only accounts with this role can grant/revoke other roles.
    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
    /// @dev Modifier that checks if an account has the specified role; reverts otherwise.
    modifier onlyRole(bytes32 role) {
        _checkRole(role, msg.sender);
        _;
    }
    /**
     *  @notice         Checks whether an account has a particular role.
     *  @dev            Returns `true` if `account` has been granted `role`.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRole(bytes32 role, address account) public view override returns (bool) {
        return _hasRole[role][account];
    }
    /**
     *  @notice         Checks whether an account has a particular role;
     *                  role restrictions can be swtiched on and off.
     *
     *  @dev            Returns `true` if `account` has been granted `role`.
     *                  Role restrictions can be swtiched on and off:
     *                      - If address(0) has ROLE, then the ROLE restrictions
     *                        don't apply.
     *                      - If address(0) does not have ROLE, then the ROLE
     *                        restrictions will apply.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRoleWithSwitch(bytes32 role, address account) public view returns (bool) {
        if (!_hasRole[role][address(0)]) {
            return _hasRole[role][account];
        }
        return true;
    }
    /**
     *  @notice         Returns the admin role that controls the specified role.
     *  @dev            See {grantRole} and {revokeRole}.
     *                  To change a role's admin, use {_setRoleAdmin}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function getRoleAdmin(bytes32 role) external view override returns (bytes32) {
        return _getRoleAdmin[role];
    }
    /**
     *  @notice         Grants a role to an account, if not previously granted.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleGranted Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account to which the role is being granted.
     */
    function grantRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        if (_hasRole[role][account]) {
            revert("Can only grant to non holders");
        }
        _setupRole(role, account);
    }
    /**
     *  @notice         Revokes role from an account.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function revokeRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        _revokeRole(role, account);
    }
    /**
     *  @notice         Revokes role from the account.
     *  @dev            Caller must have the `role`, with caller being the same as `account`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        if (msg.sender != account) {
            revert("Can only renounce for self");
        }
        _revokeRole(role, account);
    }
    /// @dev Sets `adminRole` as `role`'s admin role.
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = _getRoleAdmin[role];
        _getRoleAdmin[role] = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }
    /// @dev Sets up `role` for `account`
    function _setupRole(bytes32 role, address account) internal virtual {
        _hasRole[role][account] = true;
        emit RoleGranted(role, account, msg.sender);
    }
    /// @dev Revokes `role` from `account`
    function _revokeRole(bytes32 role, address account) internal virtual {
        _checkRole(role, account);
        delete _hasRole[role][account];
        emit RoleRevoked(role, account, msg.sender);
    }
    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!_hasRole[role][account]) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        TWStrings.toHexString(uint160(account), 20),
                        " is missing role ",
                        TWStrings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }
    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRoleWithSwitch(bytes32 role, address account) internal view virtual {
        if (!hasRoleWithSwitch(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        TWStrings.toHexString(uint160(account), 20),
                        " is missing role ",
                        TWStrings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./interface/IPermissionsEnumerable.sol";
import "./Permissions.sol";
/**
 *  @title   PermissionsEnumerable
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms.
 *           Also provides interfaces to view all members with a given role, and total count of members.
 */
contract PermissionsEnumerable is IPermissionsEnumerable, Permissions {
    /**
     *  @notice A data structure to store data of members for a given role.
     *
     *  @param index    Current index in the list of accounts that have a role.
     *  @param members  map from index => address of account that has a role
     *  @param indexOf  map from address => index which the account has.
     */
    struct RoleMembers {
        uint256 index;
        mapping(uint256 => address) members;
        mapping(address => uint256) indexOf;
    }
    /// @dev map from keccak256 hash of a role to its members' data. See {RoleMembers}.
    mapping(bytes32 => RoleMembers) private roleMembers;
    /**
     *  @notice         Returns the role-member from a list of members for a role,
     *                  at a given index.
     *  @dev            Returns `member` who has `role`, at `index` of role-members list.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param index    Index in list of current members for the role.
     *
     *  @return member  Address of account that has `role`
     */
    function getRoleMember(bytes32 role, uint256 index) external view override returns (address member) {
        uint256 currentIndex = roleMembers[role].index;
        uint256 check;
        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                if (check == index) {
                    member = roleMembers[role].members[i];
                    return member;
                }
                check += 1;
            } else if (hasRole(role, address(0)) && i == roleMembers[role].indexOf[address(0)]) {
                check += 1;
            }
        }
    }
    /**
     *  @notice         Returns total number of accounts that have a role.
     *  @dev            Returns `count` of accounts that have `role`.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *
     *  @return count   Total number of accounts that have `role`
     */
    function getRoleMemberCount(bytes32 role) external view override returns (uint256 count) {
        uint256 currentIndex = roleMembers[role].index;
        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                count += 1;
            }
        }
        if (hasRole(role, address(0))) {
            count += 1;
        }
    }
    /// @dev Revokes `role` from `account`, and removes `account` from {roleMembers}
    ///      See {_removeMember}
    function _revokeRole(bytes32 role, address account) internal override {
        super._revokeRole(role, account);
        _removeMember(role, account);
    }
    /// @dev Grants `role` to `account`, and adds `account` to {roleMembers}
    ///      See {_addMember}
    function _setupRole(bytes32 role, address account) internal override {
        super._setupRole(role, account);
        _addMember(role, account);
    }
    /// @dev adds `account` to {roleMembers}, for `role`
    function _addMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].index;
        roleMembers[role].index += 1;
        roleMembers[role].members[idx] = account;
        roleMembers[role].indexOf[account] = idx;
    }
    /// @dev removes `account` from {roleMembers}, for `role`
    function _removeMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].indexOf[account];
        delete roleMembers[role].members[idx];
        delete roleMembers[role].indexOf[account];
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
import "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
import "../openzeppelin-presets/utils/math/SafeMath.sol";
import "../eip/interface/IERC20.sol";
import "../lib/CurrencyTransferLib.sol";
import "./interface/IStaking20.sol";
abstract contract Staking20Upgradeable is ReentrancyGuardUpgradeable, IStaking20 {
    /*///////////////////////////////////////////////////////////////
                            State variables / Mappings
    //////////////////////////////////////////////////////////////*/
    /// @dev The address of the native token wrapper contract.
    address internal immutable nativeTokenWrapper;
    ///@dev Address of ERC20 contract -- staked tokens belong to this contract.
    address public stakingToken;
    /// @dev Decimals of staking token.
    uint16 public stakingTokenDecimals;
    /// @dev Decimals of reward token.
    uint16 public rewardTokenDecimals;
    ///@dev Next staking condition Id. Tracks number of conditon updates so far.
    uint64 private nextConditionId;
    /// @dev Total amount of tokens staked in the contract.
    uint256 public stakingTokenBalance;
    /// @dev List of accounts that have staked that token-id.
    address[] public stakersArray;
    ///@dev Mapping staker address to Staker struct. See {struct IStaking20.Staker}.
    mapping(address => Staker) public stakers;
    ///@dev Mapping from condition Id to staking condition. See {struct IStaking721.StakingCondition}
    mapping(uint256 => StakingCondition) private stakingConditions;
    constructor(address _nativeTokenWrapper) {
        require(_nativeTokenWrapper != address(0), "address 0");
        nativeTokenWrapper = _nativeTokenWrapper;
    }
    function __Staking20_init(
        address _stakingToken,
        uint16 _stakingTokenDecimals,
        uint16 _rewardTokenDecimals
    ) internal onlyInitializing {
        __ReentrancyGuard_init();
        require(address(_stakingToken) != address(0), "token address 0");
        require(_stakingTokenDecimals != 0 && _rewardTokenDecimals != 0, "decimals 0");
        stakingToken = _stakingToken;
        stakingTokenDecimals = _stakingTokenDecimals;
        rewardTokenDecimals = _rewardTokenDecimals;
    }
    /*///////////////////////////////////////////////////////////////
                        External/Public Functions
    //////////////////////////////////////////////////////////////*/
    /**
     *  @notice    Stake ERC20 Tokens.
     *
     *  @dev       See {_stake}. Override that to implement custom logic.
     *
     *  @param _amount    Amount to stake.
     */
    function stake(uint256 _amount) external payable nonReentrant {
        _stake(_amount);
    }
    /**
     *  @notice    Withdraw staked ERC20 tokens.
     *
     *  @dev       See {_withdraw}. Override that to implement custom logic.
     *
     *  @param _amount    Amount to withdraw.
     */
    function withdraw(uint256 _amount) external nonReentrant {
        _withdraw(_amount);
    }
    /**
     *  @notice    Claim accumulated rewards.
     *
     *  @dev       See {_claimRewards}. Override that to implement custom logic.
     *             See {_calculateRewards} for reward-calculation logic.
     */
    function claimRewards() external nonReentrant {
        _claimRewards();
    }
    /**
     *  @notice  Set time unit. Set as a number of seconds.
     *           Could be specified as -- x * 1 hours, x * 1 days, etc.
     *
     *  @dev     Only admin/authorized-account can call it.
     *
     *  @param _timeUnit    New time unit.
     */
    function setTimeUnit(uint80 _timeUnit) external virtual {
        if (!_canSetStakeConditions()) {
            revert("Not authorized");
        }
        StakingCondition memory condition = stakingConditions[nextConditionId - 1];
        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
        _setStakingCondition(_timeUnit, condition.rewardRatioNumerator, condition.rewardRatioDenominator);
        emit UpdatedTimeUnit(condition.timeUnit, _timeUnit);
    }
    /**
     *  @notice  Set rewards per unit of time.
     *           Interpreted as (numerator/denominator) rewards per second/per day/etc based on time-unit.
     *
     *           For e.g., ratio of 1/20 would mean 1 reward token for every 20 tokens staked.
     *
     *  @dev     Only admin/authorized-account can call it.
     *
     *  @param _numerator    Reward ratio numerator.
     *  @param _denominator  Reward ratio denominator.
     */
    function setRewardRatio(uint256 _numerator, uint256 _denominator) external virtual {
        if (!_canSetStakeConditions()) {
            revert("Not authorized");
        }
        StakingCondition memory condition = stakingConditions[nextConditionId - 1];
        require(
            _numerator != condition.rewardRatioNumerator || _denominator != condition.rewardRatioDenominator,
            "Reward ratio unchanged."
        );
        _setStakingCondition(condition.timeUnit, _numerator, _denominator);
        emit UpdatedRewardRatio(
            condition.rewardRatioNumerator,
            _numerator,
            condition.rewardRatioDenominator,
            _denominator
        );
    }
    /**
     *  @notice View amount staked and rewards for a user.
     *
     *  @param _staker          Address for which to calculated rewards.
     *  @return _tokensStaked   Amount of tokens staked.
     *  @return _rewards        Available reward amount.
     */
    function getStakeInfo(address _staker) external view virtual returns (uint256 _tokensStaked, uint256 _rewards) {
        _tokensStaked = stakers[_staker].amountStaked;
        _rewards = _availableRewards(_staker);
    }
    function getTimeUnit() public view returns (uint80 _timeUnit) {
        _timeUnit = stakingConditions[nextConditionId - 1].timeUnit;
    }
    function getRewardRatio() public view returns (uint256 _numerator, uint256 _denominator) {
        _numerator = stakingConditions[nextConditionId - 1].rewardRatioNumerator;
        _denominator = stakingConditions[nextConditionId - 1].rewardRatioDenominator;
    }
    /*///////////////////////////////////////////////////////////////
                            Internal Functions
    //////////////////////////////////////////////////////////////*/
    /// @dev Staking logic. Override to add custom logic.
    function _stake(uint256 _amount) internal virtual {
        require(_amount != 0, "Staking 0 tokens");
        address _stakingToken;
        if (stakingToken == CurrencyTransferLib.NATIVE_TOKEN) {
            _stakingToken = nativeTokenWrapper;
        } else {
            require(msg.value == 0, "Value not 0");
            _stakingToken = stakingToken;
        }
        if (stakers[_stakeMsgSender()].amountStaked > 0) {
            _updateUnclaimedRewardsForStaker(_stakeMsgSender());
        } else {
            stakersArray.push(_stakeMsgSender());
            stakers[_stakeMsgSender()].timeOfLastUpdate = uint80(block.timestamp);
            stakers[_stakeMsgSender()].conditionIdOflastUpdate = nextConditionId - 1;
        }
        uint256 balanceBefore = IERC20(_stakingToken).balanceOf(address(this));
        CurrencyTransferLib.transferCurrencyWithWrapper(
            stakingToken,
            _stakeMsgSender(),
            address(this),
            _amount,
            nativeTokenWrapper
        );
        uint256 actualAmount = IERC20(_stakingToken).balanceOf(address(this)) - balanceBefore;
        stakers[_stakeMsgSender()].amountStaked += actualAmount;
        stakingTokenBalance += actualAmount;
        emit TokensStaked(_stakeMsgSender(), actualAmount);
    }
    /// @dev Withdraw logic. Override to add custom logic.
    function _withdraw(uint256 _amount) internal virtual {
        uint256 _amountStaked = stakers[_stakeMsgSender()].amountStaked;
        require(_amount != 0, "Withdrawing 0 tokens");
        require(_amountStaked >= _amount, "Withdrawing more than staked");
        _updateUnclaimedRewardsForStaker(_stakeMsgSender());
        if (_amountStaked == _amount) {
            address[] memory _stakersArray = stakersArray;
            for (uint256 i = 0; i < _stakersArray.length; ++i) {
                if (_stakersArray[i] == _stakeMsgSender()) {
                    stakersArray[i] = _stakersArray[_stakersArray.length - 1];
                    stakersArray.pop();
                    break;
                }
            }
        }
        stakers[_stakeMsgSender()].amountStaked -= _amount;
        stakingTokenBalance -= _amount;
        CurrencyTransferLib.transferCurrencyWithWrapper(
            stakingToken,
            address(this),
            _stakeMsgSender(),
            _amount,
            nativeTokenWrapper
        );
        emit TokensWithdrawn(_stakeMsgSender(), _amount);
    }
    /// @dev Logic for claiming rewards. Override to add custom logic.
    function _claimRewards() internal virtual {
        uint256 rewards = stakers[_stakeMsgSender()].unclaimedRewards + _calculateRewards(_stakeMsgSender());
        require(rewards != 0, "No rewards");
        stakers[_stakeMsgSender()].timeOfLastUpdate = uint80(block.timestamp);
        stakers[_stakeMsgSender()].unclaimedRewards = 0;
        stakers[_stakeMsgSender()].conditionIdOflastUpdate = nextConditionId - 1;
        _mintRewards(_stakeMsgSender(), rewards);
        emit RewardsClaimed(_stakeMsgSender(), rewards);
    }
    /// @dev View available rewards for a user.
    function _availableRewards(address _staker) internal view virtual returns (uint256 _rewards) {
        if (stakers[_staker].amountStaked == 0) {
            _rewards = stakers[_staker].unclaimedRewards;
        } else {
            _rewards = stakers[_staker].unclaimedRewards + _calculateRewards(_staker);
        }
    }
    /// @dev Update unclaimed rewards for a users. Called for every state change for a user.
    function _updateUnclaimedRewardsForStaker(address _staker) internal virtual {
        uint256 rewards = _calculateRewards(_staker);
        stakers[_staker].unclaimedRewards += rewards;
        stakers[_staker].timeOfLastUpdate = uint80(block.timestamp);
        stakers[_staker].conditionIdOflastUpdate = nextConditionId - 1;
    }
    /// @dev Set staking conditions.
    function _setStakingCondition(
        uint80 _timeUnit,
        uint256 _numerator,
        uint256 _denominator
    ) internal virtual {
        require(_denominator != 0, "divide by 0");
        require(_timeUnit != 0, "time-unit can't be 0");
        uint256 conditionId = nextConditionId;
        nextConditionId += 1;
        stakingConditions[conditionId] = StakingCondition({
            timeUnit: _timeUnit,
            rewardRatioNumerator: _numerator,
            rewardRatioDenominator: _denominator,
            startTimestamp: uint80(block.timestamp),
            endTimestamp: 0
        });
        if (conditionId > 0) {
            stakingConditions[conditionId - 1].endTimestamp = uint80(block.timestamp);
        }
    }
    /// @dev Calculate rewards for a staker.
    function _calculateRewards(address _staker) internal view virtual returns (uint256 _rewards) {
        Staker memory staker = stakers[_staker];
        uint256 _stakerConditionId = staker.conditionIdOflastUpdate;
        uint256 _nextConditionId = nextConditionId;
        for (uint256 i = _stakerConditionId; i < _nextConditionId; i += 1) {
            StakingCondition memory condition = stakingConditions[i];
            uint256 startTime = i != _stakerConditionId ? condition.startTimestamp : staker.timeOfLastUpdate;
            uint256 endTime = condition.endTimestamp != 0 ? condition.endTimestamp : block.timestamp;
            (bool noOverflowProduct, uint256 rewardsProduct) = SafeMath.tryMul(
                (endTime - startTime) * staker.amountStaked,
                condition.rewardRatioNumerator
            );
            (bool noOverflowSum, uint256 rewardsSum) = SafeMath.tryAdd(
                _rewards,
                (rewardsProduct / condition.timeUnit) / condition.rewardRatioDenominator
            );
            _rewards = noOverflowProduct && noOverflowSum ? rewardsSum : _rewards;
        }
        (, _rewards) = SafeMath.tryMul(_rewards, 10**rewardTokenDecimals);
        _rewards /= (10**stakingTokenDecimals);
    }
    /*////////////////////////////////////////////////////////////////////
        Optional hooks that can be implemented in the derived contract
    ///////////////////////////////////////////////////////////////////*/
    /// @dev Exposes the ability to override the msg sender -- support ERC2771.
    function _stakeMsgSender() internal virtual returns (address) {
        return msg.sender;
    }
    /*///////////////////////////////////////////////////////////////
        Virtual functions to be implemented in derived contract
    //////////////////////////////////////////////////////////////*/
    /**
     *  @notice View total rewards available in the staking contract.
     *
     */
    function getRewardTokenBalance() external view virtual returns (uint256 _rewardsAvailableInContract);
    /**
     *  @dev    Mint/Transfer ERC20 rewards to the staker. Must override.
     *
     *  @param _staker    Address for which to calculated rewards.
     *  @param _rewards   Amount of tokens to be given out as reward.
     *
     *  For example, override as below to mint ERC20 rewards:
     *
     * ```
     *  function _mintRewards(address _staker, uint256 _rewards) internal override {
     *
     *      TokenERC20(rewardTokenAddress).mintTo(_staker, _rewards);
     *
     *  }
     * ```
     */
    function _mintRewards(address _staker, uint256 _rewards) internal virtual;
    /**
     *  @dev    Returns whether staking restrictions can be set in given execution context.
     *          Must override.
     *
     *
     *  For example, override as below to restrict access to admin:
     *
     * ```
     *  function _canSetStakeConditions() internal override {
     *
     *      return msg.sender == adminAddress;
     *
     *  }
     * ```
     */
    function _canSetStakeConditions() internal view virtual returns (bool);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 *  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *  for you contract.
 *
 *  Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */
interface IContractMetadata {
    /// @dev Returns the metadata URI of the contract.
    function contractURI() external view returns (string memory);
    /**
     *  @dev Sets contract URI for the storefront-level metadata of the contract.
     *       Only module admin can call this function.
     */
    function setContractURI(string calldata _uri) external;
    /// @dev Emitted when the contract URI is updated.
    event ContractURIUpdated(string prevURI, string newURI);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IPermissions {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);
    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);
    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;
    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;
    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./IPermissions.sol";
/**
 * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
 */
interface IPermissionsEnumerable is IPermissions {
    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * [forum post](https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296)
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) external view returns (address);
    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) external view returns (uint256);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
interface IStaking20 {
    /// @dev Emitted when tokens are staked.
    event TokensStaked(address indexed staker, uint256 amount);
    /// @dev Emitted when a tokens are withdrawn.
    event TokensWithdrawn(address indexed staker, uint256 amount);
    /// @dev Emitted when a staker claims staking rewards.
    event RewardsClaimed(address indexed staker, uint256 rewardAmount);
    /// @dev Emitted when contract admin updates timeUnit.
    event UpdatedTimeUnit(uint256 oldTimeUnit, uint256 newTimeUnit);
    /// @dev Emitted when contract admin updates rewardsPerUnitTime.
    event UpdatedRewardRatio(
        uint256 oldNumerator,
        uint256 newNumerator,
        uint256 oldDenominator,
        uint256 newDenominator
    );
    /// @dev Emitted when contract admin updates minimum staking amount.
    event UpdatedMinStakeAmount(uint256 oldAmount, uint256 newAmount);
    /**
     *  @notice Staker Info.
     *
     *  @param amountStaked             Total number of tokens staked by the staker.
     *
     *  @param timeOfLastUpdate         Last reward-update timestamp.
     *
     *  @param unclaimedRewards         Rewards accumulated but not claimed by user yet.
     *
     *  @param conditionIdOflastUpdate  Condition-Id when rewards were last updated for user.
     */
    struct Staker {
        uint128 timeOfLastUpdate;
        uint64 conditionIdOflastUpdate;
        uint256 amountStaked;
        uint256 unclaimedRewards;
    }
    /**
     *  @notice Staking Condition.
     *
     *  @param timeUnit                 Unit of time specified in number of seconds. Can be set as 1 seconds, 1 days, 1 hours, etc.
     *
     *  @param rewardRatioNumerator     Rewards ratio is the number of reward tokens for a number of staked tokens,
     *                                  per unit of time.
     *
     *  @param rewardRatioDenominator   Rewards ratio is the number of reward tokens for a number of staked tokens,
     *                                  per unit of time.
     *
     *  @param startTimestamp           Condition start timestamp.
     *
     *  @param endTimestamp             Condition end timestamp.
     */
    struct StakingCondition {
        uint80 timeUnit;
        uint80 startTimestamp;
        uint80 endTimestamp;
        uint256 rewardRatioNumerator;
        uint256 rewardRatioDenominator;
    }
    /**
     *  @notice Stake ERC721 Tokens.
     *
     *  @param amount    Amount to stake.
     */
    function stake(uint256 amount) external payable;
    /**
     *  @notice Withdraw staked tokens.
     *
     *  @param amount    Amount to withdraw.
     */
    function withdraw(uint256 amount) external;
    /**
     *  @notice Claim accumulated rewards.
     *
     */
    function claimRewards() external;
    /**
     *  @notice View amount staked and total rewards for a user.
     *
     *  @param staker    Address for which to calculated rewards.
     */
    function getStakeInfo(address staker) external view returns (uint256 _tokensStaked, uint256 _rewards);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
interface IWETH {
    function deposit() external payable;
    function withdraw(uint256 amount) external;
    function transfer(address to, uint256 value) external returns (bool);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/**
 *  Thirdweb's TokenStake smart contract allows users to stake their ERC-20 Tokens
 *  and earn rewards in form of a different ERC-20 token.
 *
 *  note:
 *  - Reward token and staking token can't be changed after deployment.
 *    Reward token contract can't be same as the staking token contract.
 *
 *  - ERC20 tokens from only the specified contract can be staked.
 *
 *  - All token transfers require approval on their respective token-contracts.
 *
 *  - Admin must deposit reward tokens using the `depositRewardTokens` function only.
 *    Any direct transfers may cause unintended consequences, such as locking of tokens.
 *
 *  - Users must stake tokens using the `stake` function only.
 *    Any direct transfers may cause unintended consequences, such as locking of tokens.
 */
interface ITokenStake {
    /// @dev Emitted when contract admin withdraws reward tokens.
    event RewardTokensWithdrawnByAdmin(uint256 _amount);
    /// @dev Emitted when contract admin deposits reward tokens.
    event RewardTokensDepositedByAdmin(uint256 _amount);
    /**
     *  @notice Lets a contract admin (account with `DEFAULT_ADMIN_ROLE`) deposit reward-tokens.
     *
     *          note: Tokens should be approved on the reward-token contract before depositing.
     *
     *  @param _amount     Amount of tokens to deposit.
     */
    function depositRewardTokens(uint256 _amount) external payable;
    /**
     *  @notice Lets a contract admin (account with `DEFAULT_ADMIN_ROLE`) withdraw reward-tokens.
     *          Useful for removing excess balance, thus preventing locking of tokens.
     *
     *  @param _amount     Amount of tokens to deposit.
     */
    function withdrawRewardTokens(uint256 _amount) external;
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
// Helper interfaces
import { IWETH } from "../interfaces/IWETH.sol";
import "../openzeppelin-presets/token/ERC20/utils/SafeERC20.sol";
library CurrencyTransferLib {
    using SafeERC20 for IERC20;
    /// @dev The address interpreted as native token of the chain.
    address public constant NATIVE_TOKEN = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    /// @dev Transfers a given amount of currency.
    function transferCurrency(
        address _currency,
        address _from,
        address _to,
        uint256 _amount
    ) internal {
        if (_amount == 0) {
            return;
        }
        if (_currency == NATIVE_TOKEN) {
            safeTransferNativeToken(_to, _amount);
        } else {
            safeTransferERC20(_currency, _from, _to, _amount);
        }
    }
    /// @dev Transfers a given amount of currency. (With native token wrapping)
    function transferCurrencyWithWrapper(
        address _currency,
        address _from,
        address _to,
        uint256 _amount,
        address _nativeTokenWrapper
    ) internal {
        if (_amount == 0) {
            return;
        }
        if (_currency == NATIVE_TOKEN) {
            if (_from == address(this)) {
                // withdraw from weth then transfer withdrawn native token to recipient
                IWETH(_nativeTokenWrapper).withdraw(_amount);
                safeTransferNativeTokenWithWrapper(_to, _amount, _nativeTokenWrapper);
            } else if (_to == address(this)) {
                // store native currency in weth
                require(_amount == msg.value, "msg.value != amount");
                IWETH(_nativeTokenWrapper).deposit{ value: _amount }();
            } else {
                safeTransferNativeTokenWithWrapper(_to, _amount, _nativeTokenWrapper);
            }
        } else {
            safeTransferERC20(_currency, _from, _to, _amount);
        }
    }
    /// @dev Transfer `amount` of ERC20 token from `from` to `to`.
    function safeTransferERC20(
        address _currency,
        address _from,
        address _to,
        uint256 _amount
    ) internal {
        if (_from == _to) {
            return;
        }
        if (_from == address(this)) {
            IERC20(_currency).safeTransfer(_to, _amount);
        } else {
            IERC20(_currency).safeTransferFrom(_from, _to, _amount);
        }
    }
    /// @dev Transfers `amount` of native token to `to`.
    function safeTransferNativeToken(address to, uint256 value) internal {
        // solhint-disable avoid-low-level-calls
        // slither-disable-next-line low-level-calls
        (bool success, ) = to.call{ value: value }("");
        require(success, "native token transfer failed");
    }
    /// @dev Transfers `amount` of native token to `to`. (With native token wrapping)
    function safeTransferNativeTokenWithWrapper(
        address to,
        uint256 value,
        address _nativeTokenWrapper
    ) internal {
        // solhint-disable avoid-low-level-calls
        // slither-disable-next-line low-level-calls
        (bool success, ) = to.call{ value: value }("");
        if (!success) {
            IWETH(_nativeTokenWrapper).deposit{ value: value }();
            IERC20(_nativeTokenWrapper).safeTransfer(to, value);
        }
    }
}
// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 * @dev Collection of functions related to the address type
 */
library TWAddress {
    /**
     * @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.
     *
     * [EIP1884](https://eips.ethereum.org/EIPS/eip-1884) 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: Apache 2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 * @dev String operations.
 */
library TWStrings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }
    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }
    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (metatx/ERC2771Context.sol)
pragma solidity ^0.8.11;
import "@openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
/**
 * @dev Context variant with ERC2771 support.
 */
abstract contract ERC2771ContextUpgradeable is Initializable, ContextUpgradeable {
    mapping(address => bool) private _trustedForwarder;
    function __ERC2771Context_init(address[] memory trustedForwarder) internal onlyInitializing {
        __Context_init_unchained();
        __ERC2771Context_init_unchained(trustedForwarder);
    }
    function __ERC2771Context_init_unchained(address[] memory trustedForwarder) internal onlyInitializing {
        for (uint256 i = 0; i < trustedForwarder.length; i++) {
            _trustedForwarder[trustedForwarder[i]] = true;
        }
    }
    function isTrustedForwarder(address forwarder) public view virtual returns (bool) {
        return _trustedForwarder[forwarder];
    }
    function _msgSender() internal view virtual override returns (address sender) {
        if (isTrustedForwarder(msg.sender)) {
            // The assembly code is more direct than the Solidity version using `abi.decode`.
            assembly {
                sender := shr(96, calldataload(sub(calldatasize(), 20)))
            }
        } else {
            return super._msgSender();
        }
    }
    function _msgData() internal view virtual override returns (bytes calldata) {
        if (isTrustedForwarder(msg.sender)) {
            return msg.data[:msg.data.length - 20];
        } else {
            return super._msgData();
        }
    }
    uint256[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../../../../eip/interface/IERC20.sol";
import "../../../../lib/TWAddress.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 TWAddress 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 v4.6.0) (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }
    /**
     * @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) {
        return a + b;
    }
    /**
     * @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 a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
//   $$\\     $$\\       $$\\                 $$\\                         $$\\
//   $$ |    $$ |      \\__|                $$ |                        $$ |
// $$$$$$\\   $$$$$$$\\  $$\\  $$$$$$\\   $$$$$$$ |$$\\  $$\\  $$\\  $$$$$$\\  $$$$$$$\\
// \\_$$  _|  $$  __$$\\ $$ |$$  __$$\\ $$  __$$ |$$ | $$ | $$ |$$  __$$\\ $$  __$$\\
//   $$ |    $$ |  $$ |$$ |$$ |  \\__|$$ /  $$ |$$ | $$ | $$ |$$$$$$$$ |$$ |  $$ |
//   $$ |$$\\ $$ |  $$ |$$ |$$ |      $$ |  $$ |$$ | $$ | $$ |$$   ____|$$ |  $$ |
//   \\$$$$  |$$ |  $$ |$$ |$$ |      \\$$$$$$$ |\\$$$$$\\$$$$  |\\$$$$$$$\\ $$$$$$$  |
//    \\____/ \\__|  \\__|\\__|\\__|       \\_______| \\_____\\____/  \\_______|\\_______/
// Token
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
// Meta transactions
import "../openzeppelin-presets/metatx/ERC2771ContextUpgradeable.sol";
// Utils
import "@openzeppelin/contracts-upgradeable/utils/MulticallUpgradeable.sol";
import { CurrencyTransferLib } from "../lib/CurrencyTransferLib.sol";
import "../eip/interface/IERC20Metadata.sol";
//  ==========  Features    ==========
import "../extension/ContractMetadata.sol";
import "../extension/PermissionsEnumerable.sol";
import { Staking20Upgradeable } from "../extension/Staking20Upgradeable.sol";
import "../interfaces/staking/ITokenStake.sol";
contract TokenStake is
    Initializable,
    ContractMetadata,
    PermissionsEnumerable,
    ERC2771ContextUpgradeable,
    MulticallUpgradeable,
    Staking20Upgradeable,
    ITokenStake
{
    bytes32 private constant MODULE_TYPE = bytes32("TokenStake");
    uint256 private constant VERSION = 1;
    /// @dev ERC20 Reward Token address. See {_mintRewards} below.
    address public rewardToken;
    /// @dev Total amount of reward tokens in the contract.
    uint256 private rewardTokenBalance;
    constructor(address _nativeTokenWrapper) initializer Staking20Upgradeable(_nativeTokenWrapper) {}
    /// @dev Initiliazes the contract, like a constructor.
    function initialize(
        address _defaultAdmin,
        string memory _contractURI,
        address[] memory _trustedForwarders,
        address _rewardToken,
        address _stakingToken,
        uint80 _timeUnit,
        uint256 _rewardRatioNumerator,
        uint256 _rewardRatioDenominator
    ) external initializer {
        __ERC2771Context_init_unchained(_trustedForwarders);
        require(_rewardToken != _stakingToken, "Reward Token and Staking Token can't be same.");
        rewardToken = _rewardToken;
        uint16 _stakingTokenDecimals = _stakingToken == CurrencyTransferLib.NATIVE_TOKEN
            ? 18
            : IERC20Metadata(_stakingToken).decimals();
        uint16 _rewardTokenDecimals = _rewardToken == CurrencyTransferLib.NATIVE_TOKEN
            ? 18
            : IERC20Metadata(_rewardToken).decimals();
        __Staking20_init(_stakingToken, _stakingTokenDecimals, _rewardTokenDecimals);
        _setStakingCondition(_timeUnit, _rewardRatioNumerator, _rewardRatioDenominator);
        _setupContractURI(_contractURI);
        _setupRole(DEFAULT_ADMIN_ROLE, _defaultAdmin);
    }
    /// @dev Returns the module type of the contract.
    function contractType() external pure virtual returns (bytes32) {
        return MODULE_TYPE;
    }
    /// @dev Returns the version of the contract.
    function contractVersion() external pure virtual returns (uint8) {
        return uint8(VERSION);
    }
    /// @dev Lets the contract receive ether to unwrap native tokens.
    receive() external payable {
        require(msg.sender == nativeTokenWrapper, "caller not native token wrapper.");
    }
    /// @dev Admin deposits reward tokens.
    function depositRewardTokens(uint256 _amount) external payable nonReentrant {
        require(hasRole(DEFAULT_ADMIN_ROLE, _msgSender()), "Not authorized");
        address _rewardToken = rewardToken == CurrencyTransferLib.NATIVE_TOKEN ? nativeTokenWrapper : rewardToken;
        uint256 balanceBefore = IERC20(_rewardToken).balanceOf(address(this));
        CurrencyTransferLib.transferCurrencyWithWrapper(
            rewardToken,
            _msgSender(),
            address(this),
            _amount,
            nativeTokenWrapper
        );
        uint256 actualAmount = IERC20(_rewardToken).balanceOf(address(this)) - balanceBefore;
        rewardTokenBalance += actualAmount;
        emit RewardTokensDepositedByAdmin(actualAmount);
    }
    /// @dev Admin can withdraw excess reward tokens.
    function withdrawRewardTokens(uint256 _amount) external nonReentrant {
        require(hasRole(DEFAULT_ADMIN_ROLE, _msgSender()), "Not authorized");
        // to prevent locking of direct-transferred tokens
        rewardTokenBalance = _amount > rewardTokenBalance ? 0 : rewardTokenBalance - _amount;
        CurrencyTransferLib.transferCurrencyWithWrapper(
            rewardToken,
            address(this),
            _msgSender(),
            _amount,
            nativeTokenWrapper
        );
        // The withdrawal shouldn't reduce staking token balance. `>=` accounts for any accidental transfers.
        address _stakingToken = stakingToken == CurrencyTransferLib.NATIVE_TOKEN ? nativeTokenWrapper : stakingToken;
        require(
            IERC20(_stakingToken).balanceOf(address(this)) >= stakingTokenBalance,
            "Staking token balance reduced."
        );
        emit RewardTokensWithdrawnByAdmin(_amount);
    }
    /// @notice View total rewards available in the staking contract.
    function getRewardTokenBalance() external view override returns (uint256) {
        return rewardTokenBalance;
    }
    /*///////////////////////////////////////////////////////////////
                        Transfer Staking Rewards
    //////////////////////////////////////////////////////////////*/
    /// @dev Mint/Transfer ERC20 rewards to the staker.
    function _mintRewards(address _staker, uint256 _rewards) internal override {
        require(_rewards <= rewardTokenBalance, "Not enough reward tokens");
        rewardTokenBalance -= _rewards;
        CurrencyTransferLib.transferCurrencyWithWrapper(
            rewardToken,
            address(this),
            _staker,
            _rewards,
            nativeTokenWrapper
        );
    }
    /*///////////////////////////////////////////////////////////////
                        Internal functions
    //////////////////////////////////////////////////////////////*/
    /// @dev Returns whether staking related restrictions can be set in the given execution context.
    function _canSetStakeConditions() internal view override returns (bool) {
        return hasRole(DEFAULT_ADMIN_ROLE, _msgSender());
    }
    /// @dev Checks whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view override returns (bool) {
        return hasRole(DEFAULT_ADMIN_ROLE, _msgSender());
    }
    /*///////////////////////////////////////////////////////////////
                            Miscellaneous
    //////////////////////////////////////////////////////////////*/
    function _stakeMsgSender() internal view virtual override returns (address) {
        return _msgSender();
    }
    function _msgSender() internal view virtual override returns (address sender) {
        return ERC2771ContextUpgradeable._msgSender();
    }
    function _msgData() internal view virtual override returns (bytes calldata) {
        return ERC2771ContextUpgradeable._msgData();
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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]
 * ```
 * 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. Equivalent to `reinitializer(1)`.
     */
    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.
     *
     * `initializer` is equivalent to `reinitializer(1)`, so 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.
     *
     * 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.
     */
    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.
     */
    function _disableInitializers() internal virtual {
        require(!_initializing, "Initializable: contract is initializing");
        if (_initialized < type(uint8).max) {
            _initialized = type(uint8).max;
            emit Initialized(type(uint8).max);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";
/**
 * @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 ReentrancyGuardUpgradeable is Initializable {
    // 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;
    function __ReentrancyGuard_init() internal onlyInitializing {
        __ReentrancyGuard_init_unchained();
    }
    function __ReentrancyGuard_init_unchained() internal onlyInitializing {
        _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 making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
    /**
     * @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[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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
     * ====
     *
     * [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 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
                /// @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 v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
import "../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;
    }
    /**
     * @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: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Multicall.sol)
pragma solidity ^0.8.0;
import "./AddressUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
abstract contract MulticallUpgradeable is Initializable {
    function __Multicall_init() internal onlyInitializing {
    }
    function __Multicall_init_unchained() internal onlyInitializing {
    }
    /**
     * @dev Receives and executes a batch of function calls on this contract.
     */
    function multicall(bytes[] calldata data) external virtual returns (bytes[] memory results) {
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; i++) {
            results[i] = _functionDelegateCall(address(this), data[i]);
        }
        return results;
    }
    /**
     * @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) private returns (bytes memory) {
        require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
    }
    /**
     * @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: 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: Apache-2.0
pragma solidity ^0.8.0;
/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20 {
    function totalSupply() external view returns (uint256);
    function balanceOf(address who) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);
    function transfer(address to, uint256 value) external returns (bool);
    function approve(address spender, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/**
 * @title ERC20Metadata interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
interface IERC20Metadata {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./interface/IContractMetadata.sol";
/**
 *  @title   Contract Metadata
 *  @notice  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *           for you contract.
 *           Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */
abstract contract ContractMetadata is IContractMetadata {
    /// @notice Returns the contract metadata URI.
    string public override contractURI;
    /**
     *  @notice         Lets a contract admin set the URI for contract-level metadata.
     *  @dev            Caller should be authorized to setup contractURI, e.g. contract admin.
     *                  See {_canSetContractURI}.
     *                  Emits {ContractURIUpdated Event}.
     *
     *  @param _uri     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function setContractURI(string memory _uri) external override {
        if (!_canSetContractURI()) {
            revert("Not authorized");
        }
        _setupContractURI(_uri);
    }
    /// @dev Lets a contract admin set the URI for contract-level metadata.
    function _setupContractURI(string memory _uri) internal {
        string memory prevURI = contractURI;
        contractURI = _uri;
        emit ContractURIUpdated(prevURI, _uri);
    }
    /// @dev Returns whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view virtual returns (bool);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./interface/IPermissions.sol";
import "../lib/TWStrings.sol";
/**
 *  @title   Permissions
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms
 */
contract Permissions is IPermissions {
    /// @dev Map from keccak256 hash of a role => a map from address => whether address has role.
    mapping(bytes32 => mapping(address => bool)) private _hasRole;
    /// @dev Map from keccak256 hash of a role to role admin. See {getRoleAdmin}.
    mapping(bytes32 => bytes32) private _getRoleAdmin;
    /// @dev Default admin role for all roles. Only accounts with this role can grant/revoke other roles.
    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
    /// @dev Modifier that checks if an account has the specified role; reverts otherwise.
    modifier onlyRole(bytes32 role) {
        _checkRole(role, msg.sender);
        _;
    }
    /**
     *  @notice         Checks whether an account has a particular role.
     *  @dev            Returns `true` if `account` has been granted `role`.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRole(bytes32 role, address account) public view override returns (bool) {
        return _hasRole[role][account];
    }
    /**
     *  @notice         Checks whether an account has a particular role;
     *                  role restrictions can be swtiched on and off.
     *
     *  @dev            Returns `true` if `account` has been granted `role`.
     *                  Role restrictions can be swtiched on and off:
     *                      - If address(0) has ROLE, then the ROLE restrictions
     *                        don't apply.
     *                      - If address(0) does not have ROLE, then the ROLE
     *                        restrictions will apply.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRoleWithSwitch(bytes32 role, address account) public view returns (bool) {
        if (!_hasRole[role][address(0)]) {
            return _hasRole[role][account];
        }
        return true;
    }
    /**
     *  @notice         Returns the admin role that controls the specified role.
     *  @dev            See {grantRole} and {revokeRole}.
     *                  To change a role's admin, use {_setRoleAdmin}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function getRoleAdmin(bytes32 role) external view override returns (bytes32) {
        return _getRoleAdmin[role];
    }
    /**
     *  @notice         Grants a role to an account, if not previously granted.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleGranted Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account to which the role is being granted.
     */
    function grantRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        if (_hasRole[role][account]) {
            revert("Can only grant to non holders");
        }
        _setupRole(role, account);
    }
    /**
     *  @notice         Revokes role from an account.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function revokeRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        _revokeRole(role, account);
    }
    /**
     *  @notice         Revokes role from the account.
     *  @dev            Caller must have the `role`, with caller being the same as `account`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        if (msg.sender != account) {
            revert("Can only renounce for self");
        }
        _revokeRole(role, account);
    }
    /// @dev Sets `adminRole` as `role`'s admin role.
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = _getRoleAdmin[role];
        _getRoleAdmin[role] = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }
    /// @dev Sets up `role` for `account`
    function _setupRole(bytes32 role, address account) internal virtual {
        _hasRole[role][account] = true;
        emit RoleGranted(role, account, msg.sender);
    }
    /// @dev Revokes `role` from `account`
    function _revokeRole(bytes32 role, address account) internal virtual {
        _checkRole(role, account);
        delete _hasRole[role][account];
        emit RoleRevoked(role, account, msg.sender);
    }
    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!_hasRole[role][account]) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        TWStrings.toHexString(uint160(account), 20),
                        " is missing role ",
                        TWStrings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }
    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRoleWithSwitch(bytes32 role, address account) internal view virtual {
        if (!hasRoleWithSwitch(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        TWStrings.toHexString(uint160(account), 20),
                        " is missing role ",
                        TWStrings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./interface/IPermissionsEnumerable.sol";
import "./Permissions.sol";
/**
 *  @title   PermissionsEnumerable
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms.
 *           Also provides interfaces to view all members with a given role, and total count of members.
 */
contract PermissionsEnumerable is IPermissionsEnumerable, Permissions {
    /**
     *  @notice A data structure to store data of members for a given role.
     *
     *  @param index    Current index in the list of accounts that have a role.
     *  @param members  map from index => address of account that has a role
     *  @param indexOf  map from address => index which the account has.
     */
    struct RoleMembers {
        uint256 index;
        mapping(uint256 => address) members;
        mapping(address => uint256) indexOf;
    }
    /// @dev map from keccak256 hash of a role to its members' data. See {RoleMembers}.
    mapping(bytes32 => RoleMembers) private roleMembers;
    /**
     *  @notice         Returns the role-member from a list of members for a role,
     *                  at a given index.
     *  @dev            Returns `member` who has `role`, at `index` of role-members list.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param index    Index in list of current members for the role.
     *
     *  @return member  Address of account that has `role`
     */
    function getRoleMember(bytes32 role, uint256 index) external view override returns (address member) {
        uint256 currentIndex = roleMembers[role].index;
        uint256 check;
        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                if (check == index) {
                    member = roleMembers[role].members[i];
                    return member;
                }
                check += 1;
            } else if (hasRole(role, address(0)) && i == roleMembers[role].indexOf[address(0)]) {
                check += 1;
            }
        }
    }
    /**
     *  @notice         Returns total number of accounts that have a role.
     *  @dev            Returns `count` of accounts that have `role`.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *
     *  @return count   Total number of accounts that have `role`
     */
    function getRoleMemberCount(bytes32 role) external view override returns (uint256 count) {
        uint256 currentIndex = roleMembers[role].index;
        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                count += 1;
            }
        }
        if (hasRole(role, address(0))) {
            count += 1;
        }
    }
    /// @dev Revokes `role` from `account`, and removes `account` from {roleMembers}
    ///      See {_removeMember}
    function _revokeRole(bytes32 role, address account) internal override {
        super._revokeRole(role, account);
        _removeMember(role, account);
    }
    /// @dev Grants `role` to `account`, and adds `account` to {roleMembers}
    ///      See {_addMember}
    function _setupRole(bytes32 role, address account) internal override {
        super._setupRole(role, account);
        _addMember(role, account);
    }
    /// @dev adds `account` to {roleMembers}, for `role`
    function _addMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].index;
        roleMembers[role].index += 1;
        roleMembers[role].members[idx] = account;
        roleMembers[role].indexOf[account] = idx;
    }
    /// @dev removes `account` from {roleMembers}, for `role`
    function _removeMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].indexOf[account];
        delete roleMembers[role].members[idx];
        delete roleMembers[role].indexOf[account];
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
import "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
import "../openzeppelin-presets/utils/math/SafeMath.sol";
import "../eip/interface/IERC20.sol";
import "../lib/CurrencyTransferLib.sol";
import "./interface/IStaking20.sol";
abstract contract Staking20Upgradeable is ReentrancyGuardUpgradeable, IStaking20 {
    /*///////////////////////////////////////////////////////////////
                            State variables / Mappings
    //////////////////////////////////////////////////////////////*/
    /// @dev The address of the native token wrapper contract.
    address internal immutable nativeTokenWrapper;
    ///@dev Address of ERC20 contract -- staked tokens belong to this contract.
    address public stakingToken;
    /// @dev Decimals of staking token.
    uint16 public stakingTokenDecimals;
    /// @dev Decimals of reward token.
    uint16 public rewardTokenDecimals;
    ///@dev Next staking condition Id. Tracks number of conditon updates so far.
    uint64 private nextConditionId;
    /// @dev Total amount of tokens staked in the contract.
    uint256 public stakingTokenBalance;
    /// @dev List of accounts that have staked that token-id.
    address[] public stakersArray;
    ///@dev Mapping staker address to Staker struct. See {struct IStaking20.Staker}.
    mapping(address => Staker) public stakers;
    ///@dev Mapping from condition Id to staking condition. See {struct IStaking721.StakingCondition}
    mapping(uint256 => StakingCondition) private stakingConditions;
    constructor(address _nativeTokenWrapper) {
        require(_nativeTokenWrapper != address(0), "address 0");
        nativeTokenWrapper = _nativeTokenWrapper;
    }
    function __Staking20_init(
        address _stakingToken,
        uint16 _stakingTokenDecimals,
        uint16 _rewardTokenDecimals
    ) internal onlyInitializing {
        __ReentrancyGuard_init();
        require(address(_stakingToken) != address(0), "token address 0");
        require(_stakingTokenDecimals != 0 && _rewardTokenDecimals != 0, "decimals 0");
        stakingToken = _stakingToken;
        stakingTokenDecimals = _stakingTokenDecimals;
        rewardTokenDecimals = _rewardTokenDecimals;
    }
    /*///////////////////////////////////////////////////////////////
                        External/Public Functions
    //////////////////////////////////////////////////////////////*/
    /**
     *  @notice    Stake ERC20 Tokens.
     *
     *  @dev       See {_stake}. Override that to implement custom logic.
     *
     *  @param _amount    Amount to stake.
     */
    function stake(uint256 _amount) external payable nonReentrant {
        _stake(_amount);
    }
    /**
     *  @notice    Withdraw staked ERC20 tokens.
     *
     *  @dev       See {_withdraw}. Override that to implement custom logic.
     *
     *  @param _amount    Amount to withdraw.
     */
    function withdraw(uint256 _amount) external nonReentrant {
        _withdraw(_amount);
    }
    /**
     *  @notice    Claim accumulated rewards.
     *
     *  @dev       See {_claimRewards}. Override that to implement custom logic.
     *             See {_calculateRewards} for reward-calculation logic.
     */
    function claimRewards() external nonReentrant {
        _claimRewards();
    }
    /**
     *  @notice  Set time unit. Set as a number of seconds.
     *           Could be specified as -- x * 1 hours, x * 1 days, etc.
     *
     *  @dev     Only admin/authorized-account can call it.
     *
     *  @param _timeUnit    New time unit.
     */
    function setTimeUnit(uint80 _timeUnit) external virtual {
        if (!_canSetStakeConditions()) {
            revert("Not authorized");
        }
        StakingCondition memory condition = stakingConditions[nextConditionId - 1];
        require(_timeUnit != condition.timeUnit, "Time-unit unchanged.");
        _setStakingCondition(_timeUnit, condition.rewardRatioNumerator, condition.rewardRatioDenominator);
        emit UpdatedTimeUnit(condition.timeUnit, _timeUnit);
    }
    /**
     *  @notice  Set rewards per unit of time.
     *           Interpreted as (numerator/denominator) rewards per second/per day/etc based on time-unit.
     *
     *           For e.g., ratio of 1/20 would mean 1 reward token for every 20 tokens staked.
     *
     *  @dev     Only admin/authorized-account can call it.
     *
     *  @param _numerator    Reward ratio numerator.
     *  @param _denominator  Reward ratio denominator.
     */
    function setRewardRatio(uint256 _numerator, uint256 _denominator) external virtual {
        if (!_canSetStakeConditions()) {
            revert("Not authorized");
        }
        StakingCondition memory condition = stakingConditions[nextConditionId - 1];
        require(
            _numerator != condition.rewardRatioNumerator || _denominator != condition.rewardRatioDenominator,
            "Reward ratio unchanged."
        );
        _setStakingCondition(condition.timeUnit, _numerator, _denominator);
        emit UpdatedRewardRatio(
            condition.rewardRatioNumerator,
            _numerator,
            condition.rewardRatioDenominator,
            _denominator
        );
    }
    /**
     *  @notice View amount staked and rewards for a user.
     *
     *  @param _staker          Address for which to calculated rewards.
     *  @return _tokensStaked   Amount of tokens staked.
     *  @return _rewards        Available reward amount.
     */
    function getStakeInfo(address _staker) external view virtual returns (uint256 _tokensStaked, uint256 _rewards) {
        _tokensStaked = stakers[_staker].amountStaked;
        _rewards = _availableRewards(_staker);
    }
    function getTimeUnit() public view returns (uint80 _timeUnit) {
        _timeUnit = stakingConditions[nextConditionId - 1].timeUnit;
    }
    function getRewardRatio() public view returns (uint256 _numerator, uint256 _denominator) {
        _numerator = stakingConditions[nextConditionId - 1].rewardRatioNumerator;
        _denominator = stakingConditions[nextConditionId - 1].rewardRatioDenominator;
    }
    /*///////////////////////////////////////////////////////////////
                            Internal Functions
    //////////////////////////////////////////////////////////////*/
    /// @dev Staking logic. Override to add custom logic.
    function _stake(uint256 _amount) internal virtual {
        require(_amount != 0, "Staking 0 tokens");
        address _stakingToken;
        if (stakingToken == CurrencyTransferLib.NATIVE_TOKEN) {
            _stakingToken = nativeTokenWrapper;
        } else {
            require(msg.value == 0, "Value not 0");
            _stakingToken = stakingToken;
        }
        if (stakers[_stakeMsgSender()].amountStaked > 0) {
            _updateUnclaimedRewardsForStaker(_stakeMsgSender());
        } else {
            stakersArray.push(_stakeMsgSender());
            stakers[_stakeMsgSender()].timeOfLastUpdate = uint80(block.timestamp);
            stakers[_stakeMsgSender()].conditionIdOflastUpdate = nextConditionId - 1;
        }
        uint256 balanceBefore = IERC20(_stakingToken).balanceOf(address(this));
        CurrencyTransferLib.transferCurrencyWithWrapper(
            stakingToken,
            _stakeMsgSender(),
            address(this),
            _amount,
            nativeTokenWrapper
        );
        uint256 actualAmount = IERC20(_stakingToken).balanceOf(address(this)) - balanceBefore;
        stakers[_stakeMsgSender()].amountStaked += actualAmount;
        stakingTokenBalance += actualAmount;
        emit TokensStaked(_stakeMsgSender(), actualAmount);
    }
    /// @dev Withdraw logic. Override to add custom logic.
    function _withdraw(uint256 _amount) internal virtual {
        uint256 _amountStaked = stakers[_stakeMsgSender()].amountStaked;
        require(_amount != 0, "Withdrawing 0 tokens");
        require(_amountStaked >= _amount, "Withdrawing more than staked");
        _updateUnclaimedRewardsForStaker(_stakeMsgSender());
        if (_amountStaked == _amount) {
            address[] memory _stakersArray = stakersArray;
            for (uint256 i = 0; i < _stakersArray.length; ++i) {
                if (_stakersArray[i] == _stakeMsgSender()) {
                    stakersArray[i] = _stakersArray[_stakersArray.length - 1];
                    stakersArray.pop();
                    break;
                }
            }
        }
        stakers[_stakeMsgSender()].amountStaked -= _amount;
        stakingTokenBalance -= _amount;
        CurrencyTransferLib.transferCurrencyWithWrapper(
            stakingToken,
            address(this),
            _stakeMsgSender(),
            _amount,
            nativeTokenWrapper
        );
        emit TokensWithdrawn(_stakeMsgSender(), _amount);
    }
    /// @dev Logic for claiming rewards. Override to add custom logic.
    function _claimRewards() internal virtual {
        uint256 rewards = stakers[_stakeMsgSender()].unclaimedRewards + _calculateRewards(_stakeMsgSender());
        require(rewards != 0, "No rewards");
        stakers[_stakeMsgSender()].timeOfLastUpdate = uint80(block.timestamp);
        stakers[_stakeMsgSender()].unclaimedRewards = 0;
        stakers[_stakeMsgSender()].conditionIdOflastUpdate = nextConditionId - 1;
        _mintRewards(_stakeMsgSender(), rewards);
        emit RewardsClaimed(_stakeMsgSender(), rewards);
    }
    /// @dev View available rewards for a user.
    function _availableRewards(address _staker) internal view virtual returns (uint256 _rewards) {
        if (stakers[_staker].amountStaked == 0) {
            _rewards = stakers[_staker].unclaimedRewards;
        } else {
            _rewards = stakers[_staker].unclaimedRewards + _calculateRewards(_staker);
        }
    }
    /// @dev Update unclaimed rewards for a users. Called for every state change for a user.
    function _updateUnclaimedRewardsForStaker(address _staker) internal virtual {
        uint256 rewards = _calculateRewards(_staker);
        stakers[_staker].unclaimedRewards += rewards;
        stakers[_staker].timeOfLastUpdate = uint80(block.timestamp);
        stakers[_staker].conditionIdOflastUpdate = nextConditionId - 1;
    }
    /// @dev Set staking conditions.
    function _setStakingCondition(
        uint80 _timeUnit,
        uint256 _numerator,
        uint256 _denominator
    ) internal virtual {
        require(_denominator != 0, "divide by 0");
        require(_timeUnit != 0, "time-unit can't be 0");
        uint256 conditionId = nextConditionId;
        nextConditionId += 1;
        stakingConditions[conditionId] = StakingCondition({
            timeUnit: _timeUnit,
            rewardRatioNumerator: _numerator,
            rewardRatioDenominator: _denominator,
            startTimestamp: uint80(block.timestamp),
            endTimestamp: 0
        });
        if (conditionId > 0) {
            stakingConditions[conditionId - 1].endTimestamp = uint80(block.timestamp);
        }
    }
    /// @dev Calculate rewards for a staker.
    function _calculateRewards(address _staker) internal view virtual returns (uint256 _rewards) {
        Staker memory staker = stakers[_staker];
        uint256 _stakerConditionId = staker.conditionIdOflastUpdate;
        uint256 _nextConditionId = nextConditionId;
        for (uint256 i = _stakerConditionId; i < _nextConditionId; i += 1) {
            StakingCondition memory condition = stakingConditions[i];
            uint256 startTime = i != _stakerConditionId ? condition.startTimestamp : staker.timeOfLastUpdate;
            uint256 endTime = condition.endTimestamp != 0 ? condition.endTimestamp : block.timestamp;
            (bool noOverflowProduct, uint256 rewardsProduct) = SafeMath.tryMul(
                (endTime - startTime) * staker.amountStaked,
                condition.rewardRatioNumerator
            );
            (bool noOverflowSum, uint256 rewardsSum) = SafeMath.tryAdd(
                _rewards,
                (rewardsProduct / condition.timeUnit) / condition.rewardRatioDenominator
            );
            _rewards = noOverflowProduct && noOverflowSum ? rewardsSum : _rewards;
        }
        (, _rewards) = SafeMath.tryMul(_rewards, 10**rewardTokenDecimals);
        _rewards /= (10**stakingTokenDecimals);
    }
    /*////////////////////////////////////////////////////////////////////
        Optional hooks that can be implemented in the derived contract
    ///////////////////////////////////////////////////////////////////*/
    /// @dev Exposes the ability to override the msg sender -- support ERC2771.
    function _stakeMsgSender() internal virtual returns (address) {
        return msg.sender;
    }
    /*///////////////////////////////////////////////////////////////
        Virtual functions to be implemented in derived contract
    //////////////////////////////////////////////////////////////*/
    /**
     *  @notice View total rewards available in the staking contract.
     *
     */
    function getRewardTokenBalance() external view virtual returns (uint256 _rewardsAvailableInContract);
    /**
     *  @dev    Mint/Transfer ERC20 rewards to the staker. Must override.
     *
     *  @param _staker    Address for which to calculated rewards.
     *  @param _rewards   Amount of tokens to be given out as reward.
     *
     *  For example, override as below to mint ERC20 rewards:
     *
     * ```
     *  function _mintRewards(address _staker, uint256 _rewards) internal override {
     *
     *      TokenERC20(rewardTokenAddress).mintTo(_staker, _rewards);
     *
     *  }
     * ```
     */
    function _mintRewards(address _staker, uint256 _rewards) internal virtual;
    /**
     *  @dev    Returns whether staking restrictions can be set in given execution context.
     *          Must override.
     *
     *
     *  For example, override as below to restrict access to admin:
     *
     * ```
     *  function _canSetStakeConditions() internal override {
     *
     *      return msg.sender == adminAddress;
     *
     *  }
     * ```
     */
    function _canSetStakeConditions() internal view virtual returns (bool);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 *  Thirdweb's `ContractMetadata` is a contract extension for any base contracts. It lets you set a metadata URI
 *  for you contract.
 *
 *  Additionally, `ContractMetadata` is necessary for NFT contracts that want royalties to get distributed on OpenSea.
 */
interface IContractMetadata {
    /// @dev Returns the metadata URI of the contract.
    function contractURI() external view returns (string memory);
    /**
     *  @dev Sets contract URI for the storefront-level metadata of the contract.
     *       Only module admin can call this function.
     */
    function setContractURI(string calldata _uri) external;
    /// @dev Emitted when the contract URI is updated.
    event ContractURIUpdated(string prevURI, string newURI);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IPermissions {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);
    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);
    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;
    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;
    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
import "./IPermissions.sol";
/**
 * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
 */
interface IPermissionsEnumerable is IPermissions {
    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * [forum post](https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296)
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) external view returns (address);
    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) external view returns (uint256);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
interface IStaking20 {
    /// @dev Emitted when tokens are staked.
    event TokensStaked(address indexed staker, uint256 amount);
    /// @dev Emitted when a tokens are withdrawn.
    event TokensWithdrawn(address indexed staker, uint256 amount);
    /// @dev Emitted when a staker claims staking rewards.
    event RewardsClaimed(address indexed staker, uint256 rewardAmount);
    /// @dev Emitted when contract admin updates timeUnit.
    event UpdatedTimeUnit(uint256 oldTimeUnit, uint256 newTimeUnit);
    /// @dev Emitted when contract admin updates rewardsPerUnitTime.
    event UpdatedRewardRatio(
        uint256 oldNumerator,
        uint256 newNumerator,
        uint256 oldDenominator,
        uint256 newDenominator
    );
    /// @dev Emitted when contract admin updates minimum staking amount.
    event UpdatedMinStakeAmount(uint256 oldAmount, uint256 newAmount);
    /**
     *  @notice Staker Info.
     *
     *  @param amountStaked             Total number of tokens staked by the staker.
     *
     *  @param timeOfLastUpdate         Last reward-update timestamp.
     *
     *  @param unclaimedRewards         Rewards accumulated but not claimed by user yet.
     *
     *  @param conditionIdOflastUpdate  Condition-Id when rewards were last updated for user.
     */
    struct Staker {
        uint128 timeOfLastUpdate;
        uint64 conditionIdOflastUpdate;
        uint256 amountStaked;
        uint256 unclaimedRewards;
    }
    /**
     *  @notice Staking Condition.
     *
     *  @param timeUnit                 Unit of time specified in number of seconds. Can be set as 1 seconds, 1 days, 1 hours, etc.
     *
     *  @param rewardRatioNumerator     Rewards ratio is the number of reward tokens for a number of staked tokens,
     *                                  per unit of time.
     *
     *  @param rewardRatioDenominator   Rewards ratio is the number of reward tokens for a number of staked tokens,
     *                                  per unit of time.
     *
     *  @param startTimestamp           Condition start timestamp.
     *
     *  @param endTimestamp             Condition end timestamp.
     */
    struct StakingCondition {
        uint80 timeUnit;
        uint80 startTimestamp;
        uint80 endTimestamp;
        uint256 rewardRatioNumerator;
        uint256 rewardRatioDenominator;
    }
    /**
     *  @notice Stake ERC721 Tokens.
     *
     *  @param amount    Amount to stake.
     */
    function stake(uint256 amount) external payable;
    /**
     *  @notice Withdraw staked tokens.
     *
     *  @param amount    Amount to withdraw.
     */
    function withdraw(uint256 amount) external;
    /**
     *  @notice Claim accumulated rewards.
     *
     */
    function claimRewards() external;
    /**
     *  @notice View amount staked and total rewards for a user.
     *
     *  @param staker    Address for which to calculated rewards.
     */
    function getStakeInfo(address staker) external view returns (uint256 _tokensStaked, uint256 _rewards);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
interface IWETH {
    function deposit() external payable;
    function withdraw(uint256 amount) external;
    function transfer(address to, uint256 value) external returns (bool);
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/**
 *  Thirdweb's TokenStake smart contract allows users to stake their ERC-20 Tokens
 *  and earn rewards in form of a different ERC-20 token.
 *
 *  note:
 *  - Reward token and staking token can't be changed after deployment.
 *    Reward token contract can't be same as the staking token contract.
 *
 *  - ERC20 tokens from only the specified contract can be staked.
 *
 *  - All token transfers require approval on their respective token-contracts.
 *
 *  - Admin must deposit reward tokens using the `depositRewardTokens` function only.
 *    Any direct transfers may cause unintended consequences, such as locking of tokens.
 *
 *  - Users must stake tokens using the `stake` function only.
 *    Any direct transfers may cause unintended consequences, such as locking of tokens.
 */
interface ITokenStake {
    /// @dev Emitted when contract admin withdraws reward tokens.
    event RewardTokensWithdrawnByAdmin(uint256 _amount);
    /// @dev Emitted when contract admin deposits reward tokens.
    event RewardTokensDepositedByAdmin(uint256 _amount);
    /**
     *  @notice Lets a contract admin (account with `DEFAULT_ADMIN_ROLE`) deposit reward-tokens.
     *
     *          note: Tokens should be approved on the reward-token contract before depositing.
     *
     *  @param _amount     Amount of tokens to deposit.
     */
    function depositRewardTokens(uint256 _amount) external payable;
    /**
     *  @notice Lets a contract admin (account with `DEFAULT_ADMIN_ROLE`) withdraw reward-tokens.
     *          Useful for removing excess balance, thus preventing locking of tokens.
     *
     *  @param _amount     Amount of tokens to deposit.
     */
    function withdrawRewardTokens(uint256 _amount) external;
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;
/// @author thirdweb
// Helper interfaces
import { IWETH } from "../interfaces/IWETH.sol";
import "../openzeppelin-presets/token/ERC20/utils/SafeERC20.sol";
library CurrencyTransferLib {
    using SafeERC20 for IERC20;
    /// @dev The address interpreted as native token of the chain.
    address public constant NATIVE_TOKEN = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    /// @dev Transfers a given amount of currency.
    function transferCurrency(
        address _currency,
        address _from,
        address _to,
        uint256 _amount
    ) internal {
        if (_amount == 0) {
            return;
        }
        if (_currency == NATIVE_TOKEN) {
            safeTransferNativeToken(_to, _amount);
        } else {
            safeTransferERC20(_currency, _from, _to, _amount);
        }
    }
    /// @dev Transfers a given amount of currency. (With native token wrapping)
    function transferCurrencyWithWrapper(
        address _currency,
        address _from,
        address _to,
        uint256 _amount,
        address _nativeTokenWrapper
    ) internal {
        if (_amount == 0) {
            return;
        }
        if (_currency == NATIVE_TOKEN) {
            if (_from == address(this)) {
                // withdraw from weth then transfer withdrawn native token to recipient
                IWETH(_nativeTokenWrapper).withdraw(_amount);
                safeTransferNativeTokenWithWrapper(_to, _amount, _nativeTokenWrapper);
            } else if (_to == address(this)) {
                // store native currency in weth
                require(_amount == msg.value, "msg.value != amount");
                IWETH(_nativeTokenWrapper).deposit{ value: _amount }();
            } else {
                safeTransferNativeTokenWithWrapper(_to, _amount, _nativeTokenWrapper);
            }
        } else {
            safeTransferERC20(_currency, _from, _to, _amount);
        }
    }
    /// @dev Transfer `amount` of ERC20 token from `from` to `to`.
    function safeTransferERC20(
        address _currency,
        address _from,
        address _to,
        uint256 _amount
    ) internal {
        if (_from == _to) {
            return;
        }
        if (_from == address(this)) {
            IERC20(_currency).safeTransfer(_to, _amount);
        } else {
            IERC20(_currency).safeTransferFrom(_from, _to, _amount);
        }
    }
    /// @dev Transfers `amount` of native token to `to`.
    function safeTransferNativeToken(address to, uint256 value) internal {
        // solhint-disable avoid-low-level-calls
        // slither-disable-next-line low-level-calls
        (bool success, ) = to.call{ value: value }("");
        require(success, "native token transfer failed");
    }
    /// @dev Transfers `amount` of native token to `to`. (With native token wrapping)
    function safeTransferNativeTokenWithWrapper(
        address to,
        uint256 value,
        address _nativeTokenWrapper
    ) internal {
        // solhint-disable avoid-low-level-calls
        // slither-disable-next-line low-level-calls
        (bool success, ) = to.call{ value: value }("");
        if (!success) {
            IWETH(_nativeTokenWrapper).deposit{ value: value }();
            IERC20(_nativeTokenWrapper).safeTransfer(to, value);
        }
    }
}
// SPDX-License-Identifier: Apache 2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 * @dev Collection of functions related to the address type
 */
library TWAddress {
    /**
     * @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.
     *
     * [EIP1884](https://eips.ethereum.org/EIPS/eip-1884) 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: Apache 2.0
pragma solidity ^0.8.0;
/// @author thirdweb
/**
 * @dev String operations.
 */
library TWStrings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }
    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }
    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.0 (metatx/ERC2771Context.sol)
pragma solidity ^0.8.11;
import "@openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
/**
 * @dev Context variant with ERC2771 support.
 */
abstract contract ERC2771ContextUpgradeable is Initializable, ContextUpgradeable {
    mapping(address => bool) private _trustedForwarder;
    function __ERC2771Context_init(address[] memory trustedForwarder) internal onlyInitializing {
        __Context_init_unchained();
        __ERC2771Context_init_unchained(trustedForwarder);
    }
    function __ERC2771Context_init_unchained(address[] memory trustedForwarder) internal onlyInitializing {
        for (uint256 i = 0; i < trustedForwarder.length; i++) {
            _trustedForwarder[trustedForwarder[i]] = true;
        }
    }
    function isTrustedForwarder(address forwarder) public view virtual returns (bool) {
        return _trustedForwarder[forwarder];
    }
    function _msgSender() internal view virtual override returns (address sender) {
        if (isTrustedForwarder(msg.sender)) {
            // The assembly code is more direct than the Solidity version using `abi.decode`.
            assembly {
                sender := shr(96, calldataload(sub(calldatasize(), 20)))
            }
        } else {
            return super._msgSender();
        }
    }
    function _msgData() internal view virtual override returns (bytes calldata) {
        if (isTrustedForwarder(msg.sender)) {
            return msg.data[:msg.data.length - 20];
        } else {
            return super._msgData();
        }
    }
    uint256[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../../../../eip/interface/IERC20.sol";
import "../../../../lib/TWAddress.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 TWAddress 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 v4.6.0) (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }
    /**
     * @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) {
        return a + b;
    }
    /**
     * @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 a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.11;
/// @author thirdweb
//   $$\\     $$\\       $$\\                 $$\\                         $$\\
//   $$ |    $$ |      \\__|                $$ |                        $$ |
// $$$$$$\\   $$$$$$$\\  $$\\  $$$$$$\\   $$$$$$$ |$$\\  $$\\  $$\\  $$$$$$\\  $$$$$$$\\
// \\_$$  _|  $$  __$$\\ $$ |$$  __$$\\ $$  __$$ |$$ | $$ | $$ |$$  __$$\\ $$  __$$\\
//   $$ |    $$ |  $$ |$$ |$$ |  \\__|$$ /  $$ |$$ | $$ | $$ |$$$$$$$$ |$$ |  $$ |
//   $$ |$$\\ $$ |  $$ |$$ |$$ |      $$ |  $$ |$$ | $$ | $$ |$$   ____|$$ |  $$ |
//   \\$$$$  |$$ |  $$ |$$ |$$ |      \\$$$$$$$ |\\$$$$$\\$$$$  |\\$$$$$$$\\ $$$$$$$  |
//    \\____/ \\__|  \\__|\\__|\\__|       \\_______| \\_____\\____/  \\_______|\\_______/
// Token
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
// Meta transactions
import "../openzeppelin-presets/metatx/ERC2771ContextUpgradeable.sol";
// Utils
import "@openzeppelin/contracts-upgradeable/utils/MulticallUpgradeable.sol";
import { CurrencyTransferLib } from "../lib/CurrencyTransferLib.sol";
import "../eip/interface/IERC20Metadata.sol";
//  ==========  Features    ==========
import "../extension/ContractMetadata.sol";
import "../extension/PermissionsEnumerable.sol";
import { Staking20Upgradeable } from "../extension/Staking20Upgradeable.sol";
import "../interfaces/staking/ITokenStake.sol";
contract TokenStake is
    Initializable,
    ContractMetadata,
    PermissionsEnumerable,
    ERC2771ContextUpgradeable,
    MulticallUpgradeable,
    Staking20Upgradeable,
    ITokenStake
{
    bytes32 private constant MODULE_TYPE = bytes32("TokenStake");
    uint256 private constant VERSION = 1;
    /// @dev ERC20 Reward Token address. See {_mintRewards} below.
    address public rewardToken;
    /// @dev Total amount of reward tokens in the contract.
    uint256 private rewardTokenBalance;
    constructor(address _nativeTokenWrapper) initializer Staking20Upgradeable(_nativeTokenWrapper) {}
    /// @dev Initiliazes the contract, like a constructor.
    function initialize(
        address _defaultAdmin,
        string memory _contractURI,
        address[] memory _trustedForwarders,
        address _rewardToken,
        address _stakingToken,
        uint80 _timeUnit,
        uint256 _rewardRatioNumerator,
        uint256 _rewardRatioDenominator
    ) external initializer {
        __ERC2771Context_init_unchained(_trustedForwarders);
        require(_rewardToken != _stakingToken, "Reward Token and Staking Token can't be same.");
        rewardToken = _rewardToken;
        uint16 _stakingTokenDecimals = _stakingToken == CurrencyTransferLib.NATIVE_TOKEN
            ? 18
            : IERC20Metadata(_stakingToken).decimals();
        uint16 _rewardTokenDecimals = _rewardToken == CurrencyTransferLib.NATIVE_TOKEN
            ? 18
            : IERC20Metadata(_rewardToken).decimals();
        __Staking20_init(_stakingToken, _stakingTokenDecimals, _rewardTokenDecimals);
        _setStakingCondition(_timeUnit, _rewardRatioNumerator, _rewardRatioDenominator);
        _setupContractURI(_contractURI);
        _setupRole(DEFAULT_ADMIN_ROLE, _defaultAdmin);
    }
    /// @dev Returns the module type of the contract.
    function contractType() external pure virtual returns (bytes32) {
        return MODULE_TYPE;
    }
    /// @dev Returns the version of the contract.
    function contractVersion() external pure virtual returns (uint8) {
        return uint8(VERSION);
    }
    /// @dev Lets the contract receive ether to unwrap native tokens.
    receive() external payable {
        require(msg.sender == nativeTokenWrapper, "caller not native token wrapper.");
    }
    /// @dev Admin deposits reward tokens.
    function depositRewardTokens(uint256 _amount) external payable nonReentrant {
        require(hasRole(DEFAULT_ADMIN_ROLE, _msgSender()), "Not authorized");
        address _rewardToken = rewardToken == CurrencyTransferLib.NATIVE_TOKEN ? nativeTokenWrapper : rewardToken;
        uint256 balanceBefore = IERC20(_rewardToken).balanceOf(address(this));
        CurrencyTransferLib.transferCurrencyWithWrapper(
            rewardToken,
            _msgSender(),
            address(this),
            _amount,
            nativeTokenWrapper
        );
        uint256 actualAmount = IERC20(_rewardToken).balanceOf(address(this)) - balanceBefore;
        rewardTokenBalance += actualAmount;
        emit RewardTokensDepositedByAdmin(actualAmount);
    }
    /// @dev Admin can withdraw excess reward tokens.
    function withdrawRewardTokens(uint256 _amount) external nonReentrant {
        require(hasRole(DEFAULT_ADMIN_ROLE, _msgSender()), "Not authorized");
        // to prevent locking of direct-transferred tokens
        rewardTokenBalance = _amount > rewardTokenBalance ? 0 : rewardTokenBalance - _amount;
        CurrencyTransferLib.transferCurrencyWithWrapper(
            rewardToken,
            address(this),
            _msgSender(),
            _amount,
            nativeTokenWrapper
        );
        // The withdrawal shouldn't reduce staking token balance. `>=` accounts for any accidental transfers.
        address _stakingToken = stakingToken == CurrencyTransferLib.NATIVE_TOKEN ? nativeTokenWrapper : stakingToken;
        require(
            IERC20(_stakingToken).balanceOf(address(this)) >= stakingTokenBalance,
            "Staking token balance reduced."
        );
        emit RewardTokensWithdrawnByAdmin(_amount);
    }
    /// @notice View total rewards available in the staking contract.
    function getRewardTokenBalance() external view override returns (uint256) {
        return rewardTokenBalance;
    }
    /*///////////////////////////////////////////////////////////////
                        Transfer Staking Rewards
    //////////////////////////////////////////////////////////////*/
    /// @dev Mint/Transfer ERC20 rewards to the staker.
    function _mintRewards(address _staker, uint256 _rewards) internal override {
        require(_rewards <= rewardTokenBalance, "Not enough reward tokens");
        rewardTokenBalance -= _rewards;
        CurrencyTransferLib.transferCurrencyWithWrapper(
            rewardToken,
            address(this),
            _staker,
            _rewards,
            nativeTokenWrapper
        );
    }
    /*///////////////////////////////////////////////////////////////
                        Internal functions
    //////////////////////////////////////////////////////////////*/
    /// @dev Returns whether staking related restrictions can be set in the given execution context.
    function _canSetStakeConditions() internal view override returns (bool) {
        return hasRole(DEFAULT_ADMIN_ROLE, _msgSender());
    }
    /// @dev Checks whether contract metadata can be set in the given execution context.
    function _canSetContractURI() internal view override returns (bool) {
        return hasRole(DEFAULT_ADMIN_ROLE, _msgSender());
    }
    /*///////////////////////////////////////////////////////////////
                            Miscellaneous
    //////////////////////////////////////////////////////////////*/
    function _stakeMsgSender() internal view virtual override returns (address) {
        return _msgSender();
    }
    function _msgSender() internal view virtual override returns (address sender) {
        return ERC2771ContextUpgradeable._msgSender();
    }
    function _msgData() internal view virtual override returns (bytes calldata) {
        return ERC2771ContextUpgradeable._msgData();
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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]
 * ```
 * 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. Equivalent to `reinitializer(1)`.
     */
    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.
     *
     * `initializer` is equivalent to `reinitializer(1)`, so 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.
     *
     * 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.
     */
    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.
     */
    function _disableInitializers() internal virtual {
        require(!_initializing, "Initializable: contract is initializing");
        if (_initialized < type(uint8).max) {
            _initialized = type(uint8).max;
            emit Initialized(type(uint8).max);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";
/**
 * @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 ReentrancyGuardUpgradeable is Initializable {
    // 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;
    function __ReentrancyGuard_init() internal onlyInitializing {
        __ReentrancyGuard_init_unchained();
    }
    function __ReentrancyGuard_init_unchained() internal onlyInitializing {
        _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 making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
    /**
     * @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[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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
     * ====
     *
     * [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 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
                /// @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 v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
import "../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;
    }
    /**
     * @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: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Multicall.sol)
pragma solidity ^0.8.0;
import "./AddressUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
 * @dev Provides a function to batch together multiple calls in a single external call.
 *
 * _Available since v4.1._
 */
abstract contract MulticallUpgradeable is Initializable {
    function __Multicall_init() internal onlyInitializing {
    }
    function __Multicall_init_unchained() internal onlyInitializing {
    }
    /**
     * @dev Receives and executes a batch of function calls on this contract.
     */
    function multicall(bytes[] calldata data) external virtual returns (bytes[] memory results) {
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; i++) {
            results[i] = _functionDelegateCall(address(this), data[i]);
        }
        return results;
    }
    /**
     * @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) private returns (bytes memory) {
        require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
    }
    /**
     * @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: 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);
}

// 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

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

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  All other non-permissive additional terms are considered "further
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  If the disclaimer of warranty and limitation of liability provided
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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
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    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/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
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>.

*/

pragma solidity ^0.4.19;

// Made with Hexel at www.onhexel.com

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
    if (a == 0) {
      return 0;
    }
    uint256 c = a * b;
    assert(c / a == b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    // assert(b > 0); // Solidity automatically throws when dividing by 0
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    return c;
  }

  /**
  * @dev Substracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  function Ownable() public {
    owner = msg.sender;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param newOwner The address to transfer ownership to.
   */
  function transferOwnership(address newOwner) public onlyOwner {
    require(newOwner != address(0));
    OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }
}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address who) public view returns (uint256);
  function transfer(address to, uint256 value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) public view returns (uint256);
  function transferFrom(address from, address to, uint256 value) public returns (bool);
  function approve(address spender, uint256 value) public returns (bool);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}

/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  mapping(address => uint256) balances;

  uint256 totalSupply_;

  /**
  * @dev total number of tokens in existence
  */
  function totalSupply() public view returns (uint256) {
    return totalSupply_;
  }

  /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
  function transfer(address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);

    // SafeMath.sub will throw if there is not enough balance.
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    Transfer(msg.sender, _to, _value);
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of.
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) public view returns (uint256 balance) {
    return balances[_owner];
  }

}

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal allowed;


  /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint256 the amount of tokens to be transferred
   */
  function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);

    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
    Transfer(_from, _to, _value);
    return true;
  }

  /**
   * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
   *
   * 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
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) public returns (bool) {
    allowed[msg.sender][_spender] = _value;
    Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint256 specifying the amount of tokens still available for the spender.
   */
  function allowance(address _owner, address _spender) public view returns (uint256) {
    return allowed[_owner][_spender];
  }

  /**
   * @dev Increase the amount of tokens that an owner allowed to a spender.
   *
   * approve should be called when allowed[_spender] == 0. To increment
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _addedValue The amount of tokens to increase the allowance by.
   */
  function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
    allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
    Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

  /**
   * @dev Decrease the amount of tokens that an owner allowed to a spender.
   *
   * approve should be called when allowed[_spender] == 0. To decrement
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _subtractedValue The amount of tokens to decrease the allowance by.
   */
  function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
    uint oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}

/**
 * @title Mintable token
 * @dev Simple ERC20 Token example, with mintable token creation
 * @dev Issue: * https://github.com/OpenZeppelin/zeppelin-solidity/issues/120
 * Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
 */
contract MintableToken is StandardToken, Ownable {
  event Mint(address indexed to, uint256 amount);
  event MintFinished();

  bool public mintingFinished = false;


  modifier canMint() {
    require(!mintingFinished);
    _;
  }

  /**
   * @dev Function to mint tokens
   * @param _to The address that will receive the minted tokens.
   * @param _amount The amount of tokens to mint.
   * @return A boolean that indicates if the operation was successful.
   */
  function mint(address _to, uint256 _amount) onlyOwner canMint public returns (bool) {
    totalSupply_ = totalSupply_.add(_amount);
    balances[_to] = balances[_to].add(_amount);
    Mint(_to, _amount);
    Transfer(address(0), _to, _amount);
    return true;
  }

  /**
   * @dev Function to stop minting new tokens.
   * @return True if the operation was successful.
   */
  function finishMinting() onlyOwner canMint public returns (bool) {
    mintingFinished = true;
    MintFinished();
    return true;
  }
}

contract HexelErc20Token is MintableToken {

    /*
    * Token meta data
    */
    string public name;
    string public symbol;
    uint8 constant public decimals = 18;

    function HexelErc20Token(string _name, string _symbol, uint256 _initialSupply) public {
      name = _name;
      symbol = _symbol;
      
      if (_initialSupply > 0) {
        mint(msg.sender, _initialSupply);
      }
    }

    function multiMint(address[] recipients, uint256[] values) onlyOwner canMint external {
        require(recipients.length == values.length);
        for (uint256 i = 0; i < recipients.length; i++) {
            mint(recipients[i], values[i]);
        }
    }

}