/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
import "./migrations/LibBootstrap.sol";
import "./features/Bootstrap.sol";
import "./storage/LibProxyStorage.sol";
import "./errors/LibProxyRichErrors.sol";
/// @dev An extensible proxy contract that serves as a universal entry point for
///      interacting with the 0x protocol.
contract ZeroEx {
    // solhint-disable separate-by-one-line-in-contract,indent,var-name-mixedcase
    using LibBytesV06 for bytes;
    /// @dev Construct this contract and register the `Bootstrap` feature.
    ///      After constructing this contract, `bootstrap()` should be called
    ///      to seed the initial feature set.
    constructor() public {
        // Temporarily create and register the bootstrap feature.
        // It will deregister itself after `bootstrap()` has been called.
        Bootstrap bootstrap = new Bootstrap(msg.sender);
        LibProxyStorage.getStorage().impls[bootstrap.bootstrap.selector] =
            address(bootstrap);
    }
    // solhint-disable state-visibility
    /// @dev Forwards calls to the appropriate implementation contract.
    fallback() external payable {
        bytes4 selector = msg.data.readBytes4(0);
        address impl = getFunctionImplementation(selector);
        if (impl == address(0)) {
            _revertWithData(LibProxyRichErrors.NotImplementedError(selector));
        }
        (bool success, bytes memory resultData) = impl.delegatecall(msg.data);
        if (!success) {
            _revertWithData(resultData);
        }
        _returnWithData(resultData);
    }
    /// @dev Fallback for just receiving ether.
    receive() external payable {}
    // solhint-enable state-visibility
    /// @dev Get the implementation contract of a registered function.
    /// @param selector The function selector.
    /// @return impl The implementation contract address.
    function getFunctionImplementation(bytes4 selector)
        public
        view
        returns (address impl)
    {
        return LibProxyStorage.getStorage().impls[selector];
    }
    /// @dev Revert with arbitrary bytes.
    /// @param data Revert data.
    function _revertWithData(bytes memory data) private pure {
        assembly { revert(add(data, 32), mload(data)) }
    }
    /// @dev Return with arbitrary bytes.
    /// @param data Return data.
    function _returnWithData(bytes memory data) private pure {
        assembly { return(add(data, 32), mload(data)) }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./errors/LibBytesRichErrorsV06.sol";
import "./errors/LibRichErrorsV06.sol";
library LibBytesV06 {
    using LibBytesV06 for bytes;
    /// @dev Gets the memory address for a byte array.
    /// @param input Byte array to lookup.
    /// @return memoryAddress Memory address of byte array. This
    ///         points to the header of the byte array which contains
    ///         the length.
    function rawAddress(bytes memory input)
        internal
        pure
        returns (uint256 memoryAddress)
    {
        assembly {
            memoryAddress := input
        }
        return memoryAddress;
    }
    /// @dev Gets the memory address for the contents of a byte array.
    /// @param input Byte array to lookup.
    /// @return memoryAddress Memory address of the contents of the byte array.
    function contentAddress(bytes memory input)
        internal
        pure
        returns (uint256 memoryAddress)
    {
        assembly {
            memoryAddress := add(input, 32)
        }
        return memoryAddress;
    }
    /// @dev Copies `length` bytes from memory location `source` to `dest`.
    /// @param dest memory address to copy bytes to.
    /// @param source memory address to copy bytes from.
    /// @param length number of bytes to copy.
    function memCopy(
        uint256 dest,
        uint256 source,
        uint256 length
    )
        internal
        pure
    {
        if (length < 32) {
            // Handle a partial word by reading destination and masking
            // off the bits we are interested in.
            // This correctly handles overlap, zero lengths and source == dest
            assembly {
                let mask := sub(exp(256, sub(32, length)), 1)
                let s := and(mload(source), not(mask))
                let d := and(mload(dest), mask)
                mstore(dest, or(s, d))
            }
        } else {
            // Skip the O(length) loop when source == dest.
            if (source == dest) {
                return;
            }
            // For large copies we copy whole words at a time. The final
            // word is aligned to the end of the range (instead of after the
            // previous) to handle partial words. So a copy will look like this:
            //
            //  ####
            //      ####
            //          ####
            //            ####
            //
            // We handle overlap in the source and destination range by
            // changing the copying direction. This prevents us from
            // overwriting parts of source that we still need to copy.
            //
            // This correctly handles source == dest
            //
            if (source > dest) {
                assembly {
                    // We subtract 32 from `sEnd` and `dEnd` because it
                    // is easier to compare with in the loop, and these
                    // are also the addresses we need for copying the
                    // last bytes.
                    length := sub(length, 32)
                    let sEnd := add(source, length)
                    let dEnd := add(dest, length)
                    // Remember the last 32 bytes of source
                    // This needs to be done here and not after the loop
                    // because we may have overwritten the last bytes in
                    // source already due to overlap.
                    let last := mload(sEnd)
                    // Copy whole words front to back
                    // Note: the first check is always true,
                    // this could have been a do-while loop.
                    // solhint-disable-next-line no-empty-blocks
                    for {} lt(source, sEnd) {} {
                        mstore(dest, mload(source))
                        source := add(source, 32)
                        dest := add(dest, 32)
                    }
                    // Write the last 32 bytes
                    mstore(dEnd, last)
                }
            } else {
                assembly {
                    // We subtract 32 from `sEnd` and `dEnd` because those
                    // are the starting points when copying a word at the end.
                    length := sub(length, 32)
                    let sEnd := add(source, length)
                    let dEnd := add(dest, length)
                    // Remember the first 32 bytes of source
                    // This needs to be done here and not after the loop
                    // because we may have overwritten the first bytes in
                    // source already due to overlap.
                    let first := mload(source)
                    // Copy whole words back to front
                    // We use a signed comparisson here to allow dEnd to become
                    // negative (happens when source and dest < 32). Valid
                    // addresses in local memory will never be larger than
                    // 2**255, so they can be safely re-interpreted as signed.
                    // Note: the first check is always true,
                    // this could have been a do-while loop.
                    // solhint-disable-next-line no-empty-blocks
                    for {} slt(dest, dEnd) {} {
                        mstore(dEnd, mload(sEnd))
                        sEnd := sub(sEnd, 32)
                        dEnd := sub(dEnd, 32)
                    }
                    // Write the first 32 bytes
                    mstore(dest, first)
                }
            }
        }
    }
    /// @dev Returns a slices from a byte array.
    /// @param b The byte array to take a slice from.
    /// @param from The starting index for the slice (inclusive).
    /// @param to The final index for the slice (exclusive).
    /// @return result The slice containing bytes at indices [from, to)
    function slice(
        bytes memory b,
        uint256 from,
        uint256 to
    )
        internal
        pure
        returns (bytes memory result)
    {
        // Ensure that the from and to positions are valid positions for a slice within
        // the byte array that is being used.
        if (from > to) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.FromLessThanOrEqualsToRequired,
                from,
                to
            ));
        }
        if (to > b.length) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.ToLessThanOrEqualsLengthRequired,
                to,
                b.length
            ));
        }
        // Create a new bytes structure and copy contents
        result = new bytes(to - from);
        memCopy(
            result.contentAddress(),
            b.contentAddress() + from,
            result.length
        );
        return result;
    }
    /// @dev Returns a slice from a byte array without preserving the input.
    ///      When `from == 0`, the original array will match the slice.
    ///      In other cases its state will be corrupted.
    /// @param b The byte array to take a slice from. Will be destroyed in the process.
    /// @param from The starting index for the slice (inclusive).
    /// @param to The final index for the slice (exclusive).
    /// @return result The slice containing bytes at indices [from, to)
    function sliceDestructive(
        bytes memory b,
        uint256 from,
        uint256 to
    )
        internal
        pure
        returns (bytes memory result)
    {
        // Ensure that the from and to positions are valid positions for a slice within
        // the byte array that is being used.
        if (from > to) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.FromLessThanOrEqualsToRequired,
                from,
                to
            ));
        }
        if (to > b.length) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.ToLessThanOrEqualsLengthRequired,
                to,
                b.length
            ));
        }
        // Create a new bytes structure around [from, to) in-place.
        assembly {
            result := add(b, from)
            mstore(result, sub(to, from))
        }
        return result;
    }
    /// @dev Pops the last byte off of a byte array by modifying its length.
    /// @param b Byte array that will be modified.
    /// @return result The byte that was popped off.
    function popLastByte(bytes memory b)
        internal
        pure
        returns (bytes1 result)
    {
        if (b.length == 0) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.LengthGreaterThanZeroRequired,
                b.length,
                0
            ));
        }
        // Store last byte.
        result = b[b.length - 1];
        assembly {
            // Decrement length of byte array.
            let newLen := sub(mload(b), 1)
            mstore(b, newLen)
        }
        return result;
    }
    /// @dev Tests equality of two byte arrays.
    /// @param lhs First byte array to compare.
    /// @param rhs Second byte array to compare.
    /// @return equal True if arrays are the same. False otherwise.
    function equals(
        bytes memory lhs,
        bytes memory rhs
    )
        internal
        pure
        returns (bool equal)
    {
        // Keccak gas cost is 30 + numWords * 6. This is a cheap way to compare.
        // We early exit on unequal lengths, but keccak would also correctly
        // handle this.
        return lhs.length == rhs.length && keccak256(lhs) == keccak256(rhs);
    }
    /// @dev Reads an address from a position in a byte array.
    /// @param b Byte array containing an address.
    /// @param index Index in byte array of address.
    /// @return result address from byte array.
    function readAddress(
        bytes memory b,
        uint256 index
    )
        internal
        pure
        returns (address result)
    {
        if (b.length < index + 20) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.LengthGreaterThanOrEqualsTwentyRequired,
                b.length,
                index + 20 // 20 is length of address
            ));
        }
        // Add offset to index:
        // 1. Arrays are prefixed by 32-byte length parameter (add 32 to index)
        // 2. Account for size difference between address length and 32-byte storage word (subtract 12 from index)
        index += 20;
        // Read address from array memory
        assembly {
            // 1. Add index to address of bytes array
            // 2. Load 32-byte word from memory
            // 3. Apply 20-byte mask to obtain address
            result := and(mload(add(b, index)), 0xffffffffffffffffffffffffffffffffffffffff)
        }
        return result;
    }
    /// @dev Writes an address into a specific position in a byte array.
    /// @param b Byte array to insert address into.
    /// @param index Index in byte array of address.
    /// @param input Address to put into byte array.
    function writeAddress(
        bytes memory b,
        uint256 index,
        address input
    )
        internal
        pure
    {
        if (b.length < index + 20) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.LengthGreaterThanOrEqualsTwentyRequired,
                b.length,
                index + 20 // 20 is length of address
            ));
        }
        // Add offset to index:
        // 1. Arrays are prefixed by 32-byte length parameter (add 32 to index)
        // 2. Account for size difference between address length and 32-byte storage word (subtract 12 from index)
        index += 20;
        // Store address into array memory
        assembly {
            // The address occupies 20 bytes and mstore stores 32 bytes.
            // First fetch the 32-byte word where we'll be storing the address, then
            // apply a mask so we have only the bytes in the word that the address will not occupy.
            // Then combine these bytes with the address and store the 32 bytes back to memory with mstore.
            // 1. Add index to address of bytes array
            // 2. Load 32-byte word from memory
            // 3. Apply 12-byte mask to obtain extra bytes occupying word of memory where we'll store the address
            let neighbors := and(
                mload(add(b, index)),
                0xffffffffffffffffffffffff0000000000000000000000000000000000000000
            )
            // Make sure input address is clean.
            // (Solidity does not guarantee this)
            input := and(input, 0xffffffffffffffffffffffffffffffffffffffff)
            // Store the neighbors and address into memory
            mstore(add(b, index), xor(input, neighbors))
        }
    }
    /// @dev Reads a bytes32 value from a position in a byte array.
    /// @param b Byte array containing a bytes32 value.
    /// @param index Index in byte array of bytes32 value.
    /// @return result bytes32 value from byte array.
    function readBytes32(
        bytes memory b,
        uint256 index
    )
        internal
        pure
        returns (bytes32 result)
    {
        if (b.length < index + 32) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.LengthGreaterThanOrEqualsThirtyTwoRequired,
                b.length,
                index + 32
            ));
        }
        // Arrays are prefixed by a 256 bit length parameter
        index += 32;
        // Read the bytes32 from array memory
        assembly {
            result := mload(add(b, index))
        }
        return result;
    }
    /// @dev Writes a bytes32 into a specific position in a byte array.
    /// @param b Byte array to insert <input> into.
    /// @param index Index in byte array of <input>.
    /// @param input bytes32 to put into byte array.
    function writeBytes32(
        bytes memory b,
        uint256 index,
        bytes32 input
    )
        internal
        pure
    {
        if (b.length < index + 32) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.LengthGreaterThanOrEqualsThirtyTwoRequired,
                b.length,
                index + 32
            ));
        }
        // Arrays are prefixed by a 256 bit length parameter
        index += 32;
        // Read the bytes32 from array memory
        assembly {
            mstore(add(b, index), input)
        }
    }
    /// @dev Reads a uint256 value from a position in a byte array.
    /// @param b Byte array containing a uint256 value.
    /// @param index Index in byte array of uint256 value.
    /// @return result uint256 value from byte array.
    function readUint256(
        bytes memory b,
        uint256 index
    )
        internal
        pure
        returns (uint256 result)
    {
        result = uint256(readBytes32(b, index));
        return result;
    }
    /// @dev Writes a uint256 into a specific position in a byte array.
    /// @param b Byte array to insert <input> into.
    /// @param index Index in byte array of <input>.
    /// @param input uint256 to put into byte array.
    function writeUint256(
        bytes memory b,
        uint256 index,
        uint256 input
    )
        internal
        pure
    {
        writeBytes32(b, index, bytes32(input));
    }
    /// @dev Reads an unpadded bytes4 value from a position in a byte array.
    /// @param b Byte array containing a bytes4 value.
    /// @param index Index in byte array of bytes4 value.
    /// @return result bytes4 value from byte array.
    function readBytes4(
        bytes memory b,
        uint256 index
    )
        internal
        pure
        returns (bytes4 result)
    {
        if (b.length < index + 4) {
            LibRichErrorsV06.rrevert(LibBytesRichErrorsV06.InvalidByteOperationError(
                LibBytesRichErrorsV06.InvalidByteOperationErrorCodes.LengthGreaterThanOrEqualsFourRequired,
                b.length,
                index + 4
            ));
        }
        // Arrays are prefixed by a 32 byte length field
        index += 32;
        // Read the bytes4 from array memory
        assembly {
            result := mload(add(b, index))
            // Solidity does not require us to clean the trailing bytes.
            // We do it anyway
            result := and(result, 0xFFFFFFFF00000000000000000000000000000000000000000000000000000000)
        }
        return result;
    }
    /// @dev Writes a new length to a byte array.
    ///      Decreasing length will lead to removing the corresponding lower order bytes from the byte array.
    ///      Increasing length may lead to appending adjacent in-memory bytes to the end of the byte array.
    /// @param b Bytes array to write new length to.
    /// @param length New length of byte array.
    function writeLength(bytes memory b, uint256 length)
        internal
        pure
    {
        assembly {
            mstore(b, length)
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibBytesRichErrorsV06 {
    enum InvalidByteOperationErrorCodes {
        FromLessThanOrEqualsToRequired,
        ToLessThanOrEqualsLengthRequired,
        LengthGreaterThanZeroRequired,
        LengthGreaterThanOrEqualsFourRequired,
        LengthGreaterThanOrEqualsTwentyRequired,
        LengthGreaterThanOrEqualsThirtyTwoRequired,
        LengthGreaterThanOrEqualsNestedBytesLengthRequired,
        DestinationLengthGreaterThanOrEqualSourceLengthRequired
    }
    // bytes4(keccak256("InvalidByteOperationError(uint8,uint256,uint256)"))
    bytes4 internal constant INVALID_BYTE_OPERATION_ERROR_SELECTOR =
        0x28006595;
    // solhint-disable func-name-mixedcase
    function InvalidByteOperationError(
        InvalidByteOperationErrorCodes errorCode,
        uint256 offset,
        uint256 required
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            INVALID_BYTE_OPERATION_ERROR_SELECTOR,
            errorCode,
            offset,
            required
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibRichErrorsV06 {
    // bytes4(keccak256("Error(string)"))
    bytes4 internal constant STANDARD_ERROR_SELECTOR = 0x08c379a0;
    // solhint-disable func-name-mixedcase
    /// @dev ABI encode a standard, string revert error payload.
    ///      This is the same payload that would be included by a `revert(string)`
    ///      solidity statement. It has the function signature `Error(string)`.
    /// @param message The error string.
    /// @return The ABI encoded error.
    function StandardError(string memory message)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            STANDARD_ERROR_SELECTOR,
            bytes(message)
        );
    }
    // solhint-enable func-name-mixedcase
    /// @dev Reverts an encoded rich revert reason `errorData`.
    /// @param errorData ABI encoded error data.
    function rrevert(bytes memory errorData)
        internal
        pure
    {
        assembly {
            revert(add(errorData, 0x20), mload(errorData))
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../errors/LibProxyRichErrors.sol";
library LibBootstrap {
    /// @dev Magic bytes returned by the bootstrapper to indicate success.
    ///      This is `keccack('BOOTSTRAP_SUCCESS')`.
    bytes4 internal constant BOOTSTRAP_SUCCESS = 0xd150751b;
    using LibRichErrorsV06 for bytes;
    /// @dev Perform a delegatecall and ensure it returns the magic bytes.
    /// @param target The call target.
    /// @param data The call data.
    function delegatecallBootstrapFunction(
        address target,
        bytes memory data
    )
        internal
    {
        (bool success, bytes memory resultData) = target.delegatecall(data);
        if (!success ||
            resultData.length != 32 ||
            abi.decode(resultData, (bytes4)) != BOOTSTRAP_SUCCESS)
        {
            LibProxyRichErrors.BootstrapCallFailedError(target, resultData).rrevert();
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibProxyRichErrors {
    // solhint-disable func-name-mixedcase
    function NotImplementedError(bytes4 selector)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("NotImplementedError(bytes4)")),
            selector
        );
    }
    function InvalidBootstrapCallerError(address actual, address expected)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InvalidBootstrapCallerError(address,address)")),
            actual,
            expected
        );
    }
    function InvalidDieCallerError(address actual, address expected)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InvalidDieCallerError(address,address)")),
            actual,
            expected
        );
    }
    function BootstrapCallFailedError(address target, bytes memory resultData)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("BootstrapCallFailedError(address,bytes)")),
            target,
            resultData
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../migrations/LibBootstrap.sol";
import "../storage/LibProxyStorage.sol";
import "./IBootstrap.sol";
/// @dev Detachable `bootstrap()` feature.
contract Bootstrap is
    IBootstrap
{
    // solhint-disable state-visibility,indent
    /// @dev The ZeroEx contract.
    ///      This has to be immutable to persist across delegatecalls.
    address immutable private _deployer;
    /// @dev The implementation address of this contract.
    ///      This has to be immutable to persist across delegatecalls.
    address immutable private _implementation;
    /// @dev The deployer.
    ///      This has to be immutable to persist across delegatecalls.
    address immutable private _bootstrapCaller;
    // solhint-enable state-visibility,indent
    using LibRichErrorsV06 for bytes;
    /// @dev Construct this contract and set the bootstrap migration contract.
    ///      After constructing this contract, `bootstrap()` should be called
    ///      to seed the initial feature set.
    /// @param bootstrapCaller The allowed caller of `bootstrap()`.
    constructor(address bootstrapCaller) public {
        _deployer = msg.sender;
        _implementation = address(this);
        _bootstrapCaller = bootstrapCaller;
    }
    /// @dev Bootstrap the initial feature set of this contract by delegatecalling
    ///      into `target`. Before exiting the `bootstrap()` function will
    ///      deregister itself from the proxy to prevent being called again.
    /// @param target The bootstrapper contract address.
    /// @param callData The call data to execute on `target`.
    function bootstrap(address target, bytes calldata callData) external override {
        // Only the bootstrap caller can call this function.
        if (msg.sender != _bootstrapCaller) {
            LibProxyRichErrors.InvalidBootstrapCallerError(
                msg.sender,
                _bootstrapCaller
            ).rrevert();
        }
        // Deregister.
        LibProxyStorage.getStorage().impls[this.bootstrap.selector] = address(0);
        // Self-destruct.
        Bootstrap(_implementation).die();
        // Call the bootstrapper.
        LibBootstrap.delegatecallBootstrapFunction(target, callData);
    }
    /// @dev Self-destructs this contract.
    ///      Can only be called by the deployer.
    function die() external {
        if (msg.sender != _deployer) {
            LibProxyRichErrors.InvalidDieCallerError(msg.sender, _deployer).rrevert();
        }
        selfdestruct(msg.sender);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./LibStorage.sol";
/// @dev Storage helpers for the proxy contract.
library LibProxyStorage {
    /// @dev Storage bucket for proxy contract.
    struct Storage {
        // Mapping of function selector -> function implementation
        mapping(bytes4 => address) impls;
        // The owner of the proxy contract.
        address owner;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        uint256 storageSlot = LibStorage.getStorageSlot(
            LibStorage.StorageId.Proxy
        );
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly { stor_slot := storageSlot }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Common storage helpers
library LibStorage {
    /// @dev What to bit-shift a storage ID by to get its slot.
    ///      This gives us a maximum of 2**128 inline fields in each bucket.
    uint256 private constant STORAGE_SLOT_EXP = 128;
    /// @dev Storage IDs for feature storage buckets.
    ///      WARNING: APPEND-ONLY.
    enum StorageId {
        Proxy,
        SimpleFunctionRegistry,
        Ownable,
        TokenSpender,
        TransformERC20
    }
    /// @dev Get the storage slot given a storage ID. We assign unique, well-spaced
    ///     slots to storage bucket variables to ensure they do not overlap.
    ///     See: https://solidity.readthedocs.io/en/v0.6.6/assembly.html#access-to-external-variables-functions-and-libraries
    /// @param storageId An entry in `StorageId`
    /// @return slot The storage slot.
    function getStorageSlot(StorageId storageId)
        internal
        pure
        returns (uint256 slot)
    {
        // This should never overflow with a reasonable `STORAGE_SLOT_EXP`
        // because Solidity will do a range check on `storageId` during the cast.
        return (uint256(storageId) + 1) << STORAGE_SLOT_EXP;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Detachable `bootstrap()` feature.
interface IBootstrap {
    /// @dev Bootstrap the initial feature set of this contract by delegatecalling
    ///      into `target`. Before exiting the `bootstrap()` function will
    ///      deregister itself from the proxy to prevent being called again.
    /// @param target The bootstrapper contract address.
    /// @param callData The call data to execute on `target`.
    function bootstrap(address target, bytes calldata callData) external;
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibCommonRichErrors {
    // solhint-disable func-name-mixedcase
    function OnlyCallableBySelfError(address sender)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("OnlyCallableBySelfError(address)")),
            sender
        );
    }
    function IllegalReentrancyError()
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("IllegalReentrancyError()"))
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibOwnableRichErrors {
    // solhint-disable func-name-mixedcase
    function OnlyOwnerError(
        address sender,
        address owner
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("OnlyOwnerError(address,address)")),
            sender,
            owner
        );
    }
    function TransferOwnerToZeroError()
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("TransferOwnerToZeroError()"))
        );
    }
    function MigrateCallFailedError(address target, bytes memory resultData)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("MigrateCallFailedError(address,bytes)")),
            target,
            resultData
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibSimpleFunctionRegistryRichErrors {
    // solhint-disable func-name-mixedcase
    function NotInRollbackHistoryError(bytes4 selector, address targetImpl)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("NotInRollbackHistoryError(bytes4,address)")),
            selector,
            targetImpl
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibSpenderRichErrors {
    // solhint-disable func-name-mixedcase
    function SpenderERC20TransferFromFailedError(
        address token,
        address owner,
        address to,
        uint256 amount,
        bytes memory errorData
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("SpenderERC20TransferFromFailedError(address,address,address,uint256,bytes)")),
            token,
            owner,
            to,
            amount,
            errorData
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibTransformERC20RichErrors {
    // solhint-disable func-name-mixedcase,separate-by-one-line-in-contract
    function InsufficientEthAttachedError(
        uint256 ethAttached,
        uint256 ethNeeded
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InsufficientEthAttachedError(uint256,uint256)")),
            ethAttached,
            ethNeeded
        );
    }
    function IncompleteTransformERC20Error(
        address outputToken,
        uint256 outputTokenAmount,
        uint256 minOutputTokenAmount
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("IncompleteTransformERC20Error(address,uint256,uint256)")),
            outputToken,
            outputTokenAmount,
            minOutputTokenAmount
        );
    }
    function NegativeTransformERC20OutputError(
        address outputToken,
        uint256 outputTokenLostAmount
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("NegativeTransformERC20OutputError(address,uint256)")),
            outputToken,
            outputTokenLostAmount
        );
    }
    function TransformerFailedError(
        address transformer,
        bytes memory transformerData,
        bytes memory resultData
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("TransformerFailedError(address,bytes,bytes)")),
            transformer,
            transformerData,
            resultData
        );
    }
    // Common Transformer errors ///////////////////////////////////////////////
    function OnlyCallableByDeployerError(
        address caller,
        address deployer
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("OnlyCallableByDeployerError(address,address)")),
            caller,
            deployer
        );
    }
    function InvalidExecutionContextError(
        address actualContext,
        address expectedContext
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InvalidExecutionContextError(address,address)")),
            actualContext,
            expectedContext
        );
    }
    enum InvalidTransformDataErrorCode {
        INVALID_TOKENS,
        INVALID_ARRAY_LENGTH
    }
    function InvalidTransformDataError(
        InvalidTransformDataErrorCode errorCode,
        bytes memory transformData
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InvalidTransformDataError(uint8,bytes)")),
            errorCode,
            transformData
        );
    }
    // FillQuoteTransformer errors /////////////////////////////////////////////
    function IncompleteFillSellQuoteError(
        address sellToken,
        uint256 soldAmount,
        uint256 sellAmount
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("IncompleteFillSellQuoteError(address,uint256,uint256)")),
            sellToken,
            soldAmount,
            sellAmount
        );
    }
    function IncompleteFillBuyQuoteError(
        address buyToken,
        uint256 boughtAmount,
        uint256 buyAmount
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("IncompleteFillBuyQuoteError(address,uint256,uint256)")),
            buyToken,
            boughtAmount,
            buyAmount
        );
    }
    function InsufficientTakerTokenError(
        uint256 tokenBalance,
        uint256 tokensNeeded
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InsufficientTakerTokenError(uint256,uint256)")),
            tokenBalance,
            tokensNeeded
        );
    }
    function InsufficientProtocolFeeError(
        uint256 ethBalance,
        uint256 ethNeeded
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InsufficientProtocolFeeError(uint256,uint256)")),
            ethBalance,
            ethNeeded
        );
    }
    function InvalidERC20AssetDataError(
        bytes memory assetData
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InvalidERC20AssetDataError(bytes)")),
            assetData
        );
    }
    function InvalidTakerFeeTokenError(
        address token
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("InvalidTakerFeeTokenError(address)")),
            token
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibWalletRichErrors {
    // solhint-disable func-name-mixedcase
    function WalletExecuteCallFailedError(
        address wallet,
        address callTarget,
        bytes memory callData,
        uint256 callValue,
        bytes memory errorData
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("WalletExecuteCallFailedError(address,address,bytes,uint256,bytes)")),
            wallet,
            callTarget,
            callData,
            callValue,
            errorData
        );
    }
    function WalletExecuteDelegateCallFailedError(
        address wallet,
        address callTarget,
        bytes memory callData,
        bytes memory errorData
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            bytes4(keccak256("WalletExecuteDelegateCallFailedError(address,address,bytes,bytes)")),
            wallet,
            callTarget,
            callData,
            errorData
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/AuthorizableV06.sol";
import "../errors/LibSpenderRichErrors.sol";
import "./IAllowanceTarget.sol";
/// @dev The allowance target for the TokenSpender feature.
contract AllowanceTarget is
    IAllowanceTarget,
    AuthorizableV06
{
    // solhint-disable no-unused-vars,indent,no-empty-blocks
    using LibRichErrorsV06 for bytes;
    /// @dev Execute an arbitrary call. Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @return resultData The data returned by the call.
    function executeCall(
        address payable target,
        bytes calldata callData
    )
        external
        override
        onlyAuthorized
        returns (bytes memory resultData)
    {
        bool success;
        (success, resultData) = target.call(callData);
        if (!success) {
            resultData.rrevert();
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./interfaces/IAuthorizableV06.sol";
import "./errors/LibRichErrorsV06.sol";
import "./errors/LibAuthorizableRichErrorsV06.sol";
import "./OwnableV06.sol";
// solhint-disable no-empty-blocks
contract AuthorizableV06 is
    OwnableV06,
    IAuthorizableV06
{
    /// @dev Only authorized addresses can invoke functions with this modifier.
    modifier onlyAuthorized {
        _assertSenderIsAuthorized();
        _;
    }
    // @dev Whether an address is authorized to call privileged functions.
    // @param 0 Address to query.
    // @return 0 Whether the address is authorized.
    mapping (address => bool) public override authorized;
    // @dev Whether an address is authorized to call privileged functions.
    // @param 0 Index of authorized address.
    // @return 0 Authorized address.
    address[] public override authorities;
    /// @dev Initializes the `owner` address.
    constructor()
        public
        OwnableV06()
    {}
    /// @dev Authorizes an address.
    /// @param target Address to authorize.
    function addAuthorizedAddress(address target)
        external
        override
        onlyOwner
    {
        _addAuthorizedAddress(target);
    }
    /// @dev Removes authorizion of an address.
    /// @param target Address to remove authorization from.
    function removeAuthorizedAddress(address target)
        external
        override
        onlyOwner
    {
        if (!authorized[target]) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.TargetNotAuthorizedError(target));
        }
        for (uint256 i = 0; i < authorities.length; i++) {
            if (authorities[i] == target) {
                _removeAuthorizedAddressAtIndex(target, i);
                break;
            }
        }
    }
    /// @dev Removes authorizion of an address.
    /// @param target Address to remove authorization from.
    /// @param index Index of target in authorities array.
    function removeAuthorizedAddressAtIndex(
        address target,
        uint256 index
    )
        external
        override
        onlyOwner
    {
        _removeAuthorizedAddressAtIndex(target, index);
    }
    /// @dev Gets all authorized addresses.
    /// @return Array of authorized addresses.
    function getAuthorizedAddresses()
        external
        override
        view
        returns (address[] memory)
    {
        return authorities;
    }
    /// @dev Reverts if msg.sender is not authorized.
    function _assertSenderIsAuthorized()
        internal
        view
    {
        if (!authorized[msg.sender]) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.SenderNotAuthorizedError(msg.sender));
        }
    }
    /// @dev Authorizes an address.
    /// @param target Address to authorize.
    function _addAuthorizedAddress(address target)
        internal
    {
        // Ensure that the target is not the zero address.
        if (target == address(0)) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.ZeroCantBeAuthorizedError());
        }
        // Ensure that the target is not already authorized.
        if (authorized[target]) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.TargetAlreadyAuthorizedError(target));
        }
        authorized[target] = true;
        authorities.push(target);
        emit AuthorizedAddressAdded(target, msg.sender);
    }
    /// @dev Removes authorizion of an address.
    /// @param target Address to remove authorization from.
    /// @param index Index of target in authorities array.
    function _removeAuthorizedAddressAtIndex(
        address target,
        uint256 index
    )
        internal
    {
        if (!authorized[target]) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.TargetNotAuthorizedError(target));
        }
        if (index >= authorities.length) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.IndexOutOfBoundsError(
                index,
                authorities.length
            ));
        }
        if (authorities[index] != target) {
            LibRichErrorsV06.rrevert(LibAuthorizableRichErrorsV06.AuthorizedAddressMismatchError(
                authorities[index],
                target
            ));
        }
        delete authorized[target];
        authorities[index] = authorities[authorities.length - 1];
        authorities.pop();
        emit AuthorizedAddressRemoved(target, msg.sender);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./IOwnableV06.sol";
interface IAuthorizableV06 is
    IOwnableV06
{
    // Event logged when a new address is authorized.
    event AuthorizedAddressAdded(
        address indexed target,
        address indexed caller
    );
    // Event logged when a currently authorized address is unauthorized.
    event AuthorizedAddressRemoved(
        address indexed target,
        address indexed caller
    );
    /// @dev Authorizes an address.
    /// @param target Address to authorize.
    function addAuthorizedAddress(address target)
        external;
    /// @dev Removes authorizion of an address.
    /// @param target Address to remove authorization from.
    function removeAuthorizedAddress(address target)
        external;
    /// @dev Removes authorizion of an address.
    /// @param target Address to remove authorization from.
    /// @param index Index of target in authorities array.
    function removeAuthorizedAddressAtIndex(
        address target,
        uint256 index
    )
        external;
    /// @dev Gets all authorized addresses.
    /// @return authorizedAddresses Array of authorized addresses.
    function getAuthorizedAddresses()
        external
        view
        returns (address[] memory authorizedAddresses);
    /// @dev Whether an adderss is authorized to call privileged functions.
    /// @param addr Address to query.
    /// @return isAuthorized Whether the address is authorized.
    function authorized(address addr) external view returns (bool isAuthorized);
    /// @dev All addresseses authorized to call privileged functions.
    /// @param idx Index of authorized address.
    /// @return addr Authorized address.
    function authorities(uint256 idx) external view returns (address addr);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
interface IOwnableV06 {
    /// @dev Emitted by Ownable when ownership is transferred.
    /// @param previousOwner The previous owner of the contract.
    /// @param newOwner The new owner of the contract.
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /// @dev Transfers ownership of the contract to a new address.
    /// @param newOwner The address that will become the owner.
    function transferOwnership(address newOwner) external;
    /// @dev The owner of this contract.
    /// @return ownerAddress The owner address.
    function owner() external view returns (address ownerAddress);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibAuthorizableRichErrorsV06 {
    // bytes4(keccak256("AuthorizedAddressMismatchError(address,address)"))
    bytes4 internal constant AUTHORIZED_ADDRESS_MISMATCH_ERROR_SELECTOR =
        0x140a84db;
    // bytes4(keccak256("IndexOutOfBoundsError(uint256,uint256)"))
    bytes4 internal constant INDEX_OUT_OF_BOUNDS_ERROR_SELECTOR =
        0xe9f83771;
    // bytes4(keccak256("SenderNotAuthorizedError(address)"))
    bytes4 internal constant SENDER_NOT_AUTHORIZED_ERROR_SELECTOR =
        0xb65a25b9;
    // bytes4(keccak256("TargetAlreadyAuthorizedError(address)"))
    bytes4 internal constant TARGET_ALREADY_AUTHORIZED_ERROR_SELECTOR =
        0xde16f1a0;
    // bytes4(keccak256("TargetNotAuthorizedError(address)"))
    bytes4 internal constant TARGET_NOT_AUTHORIZED_ERROR_SELECTOR =
        0xeb5108a2;
    // bytes4(keccak256("ZeroCantBeAuthorizedError()"))
    bytes internal constant ZERO_CANT_BE_AUTHORIZED_ERROR_BYTES =
        hex"57654fe4";
    // solhint-disable func-name-mixedcase
    function AuthorizedAddressMismatchError(
        address authorized,
        address target
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            AUTHORIZED_ADDRESS_MISMATCH_ERROR_SELECTOR,
            authorized,
            target
        );
    }
    function IndexOutOfBoundsError(
        uint256 index,
        uint256 length
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            INDEX_OUT_OF_BOUNDS_ERROR_SELECTOR,
            index,
            length
        );
    }
    function SenderNotAuthorizedError(address sender)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            SENDER_NOT_AUTHORIZED_ERROR_SELECTOR,
            sender
        );
    }
    function TargetAlreadyAuthorizedError(address target)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            TARGET_ALREADY_AUTHORIZED_ERROR_SELECTOR,
            target
        );
    }
    function TargetNotAuthorizedError(address target)
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            TARGET_NOT_AUTHORIZED_ERROR_SELECTOR,
            target
        );
    }
    function ZeroCantBeAuthorizedError()
        internal
        pure
        returns (bytes memory)
    {
        return ZERO_CANT_BE_AUTHORIZED_ERROR_BYTES;
    }
}
/*
  Copyright 2019 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./interfaces/IOwnableV06.sol";
import "./errors/LibRichErrorsV06.sol";
import "./errors/LibOwnableRichErrorsV06.sol";
contract OwnableV06 is
    IOwnableV06
{
    /// @dev The owner of this contract.
    /// @return 0 The owner address.
    address public override owner;
    constructor() public {
        owner = msg.sender;
    }
    modifier onlyOwner() {
        _assertSenderIsOwner();
        _;
    }
    /// @dev Change the owner of this contract.
    /// @param newOwner New owner address.
    function transferOwnership(address newOwner)
        public
        override
        onlyOwner
    {
        if (newOwner == address(0)) {
            LibRichErrorsV06.rrevert(LibOwnableRichErrorsV06.TransferOwnerToZeroError());
        } else {
            owner = newOwner;
            emit OwnershipTransferred(msg.sender, newOwner);
        }
    }
    function _assertSenderIsOwner()
        internal
        view
    {
        if (msg.sender != owner) {
            LibRichErrorsV06.rrevert(LibOwnableRichErrorsV06.OnlyOwnerError(
                msg.sender,
                owner
            ));
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibOwnableRichErrorsV06 {
    // bytes4(keccak256("OnlyOwnerError(address,address)"))
    bytes4 internal constant ONLY_OWNER_ERROR_SELECTOR =
        0x1de45ad1;
    // bytes4(keccak256("TransferOwnerToZeroError()"))
    bytes internal constant TRANSFER_OWNER_TO_ZERO_ERROR_BYTES =
        hex"e69edc3e";
    // solhint-disable func-name-mixedcase
    function OnlyOwnerError(
        address sender,
        address owner
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            ONLY_OWNER_ERROR_SELECTOR,
            sender,
            owner
        );
    }
    function TransferOwnerToZeroError()
        internal
        pure
        returns (bytes memory)
    {
        return TRANSFER_OWNER_TO_ZERO_ERROR_BYTES;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/interfaces/IAuthorizableV06.sol";
/// @dev The allowance target for the TokenSpender feature.
interface IAllowanceTarget is
    IAuthorizableV06
{
    /// @dev Execute an arbitrary call. Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @return resultData The data returned by the call.
    function executeCall(
        address payable target,
        bytes calldata callData
    )
        external
        returns (bytes memory resultData);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/errors/LibOwnableRichErrorsV06.sol";
import "../errors/LibWalletRichErrors.sol";
import "./IFlashWallet.sol";
/// @dev A contract that can execute arbitrary calls from its owner.
contract FlashWallet is
    IFlashWallet
{
    // solhint-disable no-unused-vars,indent,no-empty-blocks
    using LibRichErrorsV06 for bytes;
    // solhint-disable
    /// @dev Store the owner/deployer as an immutable to make this contract stateless.
    address public override immutable owner;
    // solhint-enable
    constructor() public {
        // The deployer is the owner.
        owner = msg.sender;
    }
    /// @dev Allows only the (immutable) owner to call a function.
    modifier onlyOwner() virtual {
        if (msg.sender != owner) {
            LibOwnableRichErrorsV06.OnlyOwnerError(
                msg.sender,
                owner
            ).rrevert();
        }
        _;
    }
    /// @dev Execute an arbitrary call. Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @param value Ether to attach to the call.
    /// @return resultData The data returned by the call.
    function executeCall(
        address payable target,
        bytes calldata callData,
        uint256 value
    )
        external
        payable
        override
        onlyOwner
        returns (bytes memory resultData)
    {
        bool success;
        (success, resultData) = target.call{value: value}(callData);
        if (!success) {
            LibWalletRichErrors
                .WalletExecuteCallFailedError(
                    address(this),
                    target,
                    callData,
                    value,
                    resultData
                )
                .rrevert();
        }
    }
    /// @dev Execute an arbitrary delegatecall, in the context of this puppet.
    ///      Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @return resultData The data returned by the call.
    function executeDelegateCall(
        address payable target,
        bytes calldata callData
    )
        external
        payable
        override
        onlyOwner
        returns (bytes memory resultData)
    {
        bool success;
        (success, resultData) = target.delegatecall(callData);
        if (!success) {
            LibWalletRichErrors
                .WalletExecuteDelegateCallFailedError(
                    address(this),
                    target,
                    callData,
                    resultData
                )
                .rrevert();
        }
    }
    // solhint-disable
    /// @dev Allows this contract to receive ether.
    receive() external override payable {}
    // solhint-enable
    /// @dev Signal support for receiving ERC1155 tokens.
    /// @param interfaceID The interface ID, as per ERC-165 rules.
    /// @return hasSupport `true` if this contract supports an ERC-165 interface.
    function supportsInterface(bytes4 interfaceID)
        external
        pure
        returns (bool hasSupport)
    {
        return  interfaceID == this.supportsInterface.selector ||
                interfaceID == this.onERC1155Received.selector ^ this.onERC1155BatchReceived.selector ||
                interfaceID == this.tokenFallback.selector;
    }
    ///  @dev Allow this contract to receive ERC1155 tokens.
    ///  @return success  `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
    function onERC1155Received(
        address, // operator,
        address, // from,
        uint256, // id,
        uint256, // value,
        bytes calldata //data
    )
        external
        pure
        returns (bytes4 success)
    {
        return this.onERC1155Received.selector;
    }
    ///  @dev Allow this contract to receive ERC1155 tokens.
    ///  @return success  `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
    function onERC1155BatchReceived(
        address, // operator,
        address, // from,
        uint256[] calldata, // ids,
        uint256[] calldata, // values,
        bytes calldata // data
    )
        external
        pure
        returns (bytes4 success)
    {
        return this.onERC1155BatchReceived.selector;
    }
    /// @dev Allows this contract to receive ERC223 tokens.
    function tokenFallback(
        address, // from,
        uint256, // value,
        bytes calldata // value
    )
        external
        pure
    {}
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/interfaces/IOwnableV06.sol";
/// @dev A contract that can execute arbitrary calls from its owner.
interface IFlashWallet {
    /// @dev Execute an arbitrary call. Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @param value Ether to attach to the call.
    /// @return resultData The data returned by the call.
    function executeCall(
        address payable target,
        bytes calldata callData,
        uint256 value
    )
        external
        payable
        returns (bytes memory resultData);
    /// @dev Execute an arbitrary delegatecall, in the context of this puppet.
    ///      Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @return resultData The data returned by the call.
    function executeDelegateCall(
        address payable target,
        bytes calldata callData
    )
        external
        payable
        returns (bytes memory resultData);
    /// @dev Allows the puppet to receive ETH.
    receive() external payable;
    /// @dev Fetch the immutable owner/deployer of this contract.
    /// @return owner_ The immutable owner/deployer/
    function owner() external view returns (address owner_);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/AuthorizableV06.sol";
/// @dev A contract with a `die()` function.
interface IKillable {
    function die() external;
}
/// @dev Deployer contract for ERC20 transformers.
///      Only authorities may call `deploy()` and `kill()`.
contract TransformerDeployer is
    AuthorizableV06
{
    /// @dev Emitted when a contract is deployed via `deploy()`.
    /// @param deployedAddress The address of the deployed contract.
    /// @param nonce The deployment nonce.
    /// @param sender The caller of `deploy()`.
    event Deployed(address deployedAddress, uint256 nonce, address sender);
    /// @dev Emitted when a contract is killed via `kill()`.
    /// @param target The address of the contract being killed..
    /// @param sender The caller of `kill()`.
    event Killed(address target, address sender);
    // @dev The current nonce of this contract.
    uint256 public nonce = 1;
    // @dev Mapping of deployed contract address to deployment nonce.
    mapping (address => uint256) public toDeploymentNonce;
    /// @dev Create this contract and register authorities.
    constructor(address[] memory authorities) public {
        for (uint256 i = 0; i < authorities.length; ++i) {
            _addAuthorizedAddress(authorities[i]);
        }
    }
    /// @dev Deploy a new contract. Only callable by an authority.
    ///      Any attached ETH will also be forwarded.
    function deploy(bytes memory bytecode)
        public
        payable
        onlyAuthorized
        returns (address deployedAddress)
    {
        uint256 deploymentNonce = nonce;
        nonce += 1;
        assembly {
            deployedAddress := create(callvalue(), add(bytecode, 32), mload(bytecode))
        }
        toDeploymentNonce[deployedAddress] = deploymentNonce;
        emit Deployed(deployedAddress, deploymentNonce, msg.sender);
    }
    /// @dev Call `die()` on a contract. Only callable by an authority.
    function kill(IKillable target)
        public
        onlyAuthorized
    {
        target.die();
        emit Killed(address(target), msg.sender);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Basic interface for a feature contract.
interface IFeature {
    // solhint-disable func-name-mixedcase
    /// @dev The name of this feature set.
    function FEATURE_NAME() external view returns (string memory name);
    /// @dev The version of this feature set.
    function FEATURE_VERSION() external view returns (uint256 version);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/interfaces/IOwnableV06.sol";
// solhint-disable no-empty-blocks
/// @dev Owner management and migration features.
interface IOwnable is
    IOwnableV06
{
    /// @dev Emitted when `migrate()` is called.
    /// @param caller The caller of `migrate()`.
    /// @param migrator The migration contract.
    /// @param newOwner The address of the new owner.
    event Migrated(address caller, address migrator, address newOwner);
    /// @dev Execute a migration function in the context of the ZeroEx contract.
    ///      The result of the function being called should be the magic bytes
    ///      0x2c64c5ef (`keccack('MIGRATE_SUCCESS')`). Only callable by the owner.
    ///      The owner will be temporarily set to `address(this)` inside the call.
    ///      Before returning, the owner will be set to `newOwner`.
    /// @param target The migrator contract address.
    /// @param newOwner The address of the new owner.
    /// @param data The call data.
    function migrate(address target, bytes calldata data, address newOwner) external;
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Basic registry management features.
interface ISimpleFunctionRegistry {
    /// @dev A function implementation was updated via `extend()` or `rollback()`.
    /// @param selector The function selector.
    /// @param oldImpl The implementation contract address being replaced.
    /// @param newImpl The replacement implementation contract address.
    event ProxyFunctionUpdated(bytes4 indexed selector, address oldImpl, address newImpl);
    /// @dev Roll back to a prior implementation of a function.
    /// @param selector The function selector.
    /// @param targetImpl The address of an older implementation of the function.
    function rollback(bytes4 selector, address targetImpl) external;
    /// @dev Register or replace a function.
    /// @param selector The function selector.
    /// @param impl The implementation contract for the function.
    function extend(bytes4 selector, address impl) external;
    /// @dev Retrieve the length of the rollback history for a function.
    /// @param selector The function selector.
    /// @return rollbackLength The number of items in the rollback history for
    ///         the function.
    function getRollbackLength(bytes4 selector)
        external
        view
        returns (uint256 rollbackLength);
    /// @dev Retrieve an entry in the rollback history for a function.
    /// @param selector The function selector.
    /// @param idx The index in the rollback history.
    /// @return impl An implementation address for the function at
    ///         index `idx`.
    function getRollbackEntryAtIndex(bytes4 selector, uint256 idx)
        external
        view
        returns (address impl);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
/// @dev Feature that allows spending token allowances.
interface ITokenSpender {
    /// @dev Transfers ERC20 tokens from `owner` to `to`.
    ///      Only callable from within.
    /// @param token The token to spend.
    /// @param owner The owner of the tokens.
    /// @param to The recipient of the tokens.
    /// @param amount The amount of `token` to transfer.
    function _spendERC20Tokens(
        IERC20TokenV06 token,
        address owner,
        address to,
        uint256 amount
    )
        external;
    /// @dev Gets the maximum amount of an ERC20 token `token` that can be
    ///      pulled from `owner`.
    /// @param token The token to spend.
    /// @param owner The owner of the tokens.
    /// @return amount The amount of tokens that can be pulled.
    function getSpendableERC20BalanceOf(IERC20TokenV06 token, address owner)
        external
        view
        returns (uint256 amount);
    /// @dev Get the address of the allowance target.
    /// @return target The target of token allowances.
    function getAllowanceTarget() external view returns (address target);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
interface IERC20TokenV06 {
    // solhint-disable no-simple-event-func-name
    event Transfer(
        address indexed from,
        address indexed to,
        uint256 value
    );
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    /// @dev send `value` token to `to` from `msg.sender`
    /// @param to The address of the recipient
    /// @param value The amount of token to be transferred
    /// @return True if transfer was successful
    function transfer(address to, uint256 value)
        external
        returns (bool);
    /// @dev send `value` token to `to` from `from` on the condition it is approved by `from`
    /// @param from The address of the sender
    /// @param to The address of the recipient
    /// @param value The amount of token to be transferred
    /// @return True if transfer was successful
    function transferFrom(
        address from,
        address to,
        uint256 value
    )
        external
        returns (bool);
    /// @dev `msg.sender` approves `spender` to spend `value` tokens
    /// @param spender The address of the account able to transfer the tokens
    /// @param value The amount of wei to be approved for transfer
    /// @return Always true if the call has enough gas to complete execution
    function approve(address spender, uint256 value)
        external
        returns (bool);
    /// @dev Query total supply of token
    /// @return Total supply of token
    function totalSupply()
        external
        view
        returns (uint256);
    /// @dev Get the balance of `owner`.
    /// @param owner The address from which the balance will be retrieved
    /// @return Balance of owner
    function balanceOf(address owner)
        external
        view
        returns (uint256);
    /// @dev Get the allowance for `spender` to spend from `owner`.
    /// @param owner The address of the account owning tokens
    /// @param spender The address of the account able to transfer the tokens
    /// @return Amount of remaining tokens allowed to spent
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);
    /// @dev Get the number of decimals this token has.
    function decimals()
        external
        view
        returns (uint8);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "../transformers/IERC20Transformer.sol";
import "../external/IFlashWallet.sol";
/// @dev Feature to composably transform between ERC20 tokens.
interface ITransformERC20 {
    /// @dev Defines a transformation to run in `transformERC20()`.
    struct Transformation {
        // The deployment nonce for the transformer.
        // The address of the transformer contract will be derived from this
        // value.
        uint32 deploymentNonce;
        // Arbitrary data to pass to the transformer.
        bytes data;
    }
    /// @dev Raised upon a successful `transformERC20`.
    /// @param taker The taker (caller) address.
    /// @param inputToken The token being provided by the taker.
    ///        If `0xeee...`, ETH is implied and should be provided with the call.`
    /// @param outputToken The token to be acquired by the taker.
    ///        `0xeee...` implies ETH.
    /// @param inputTokenAmount The amount of `inputToken` to take from the taker.
    /// @param outputTokenAmount The amount of `outputToken` received by the taker.
    event TransformedERC20(
        address indexed taker,
        address inputToken,
        address outputToken,
        uint256 inputTokenAmount,
        uint256 outputTokenAmount
    );
    /// @dev Raised when `setTransformerDeployer()` is called.
    /// @param transformerDeployer The new deployer address.
    event TransformerDeployerUpdated(address transformerDeployer);
    /// @dev Replace the allowed deployer for transformers.
    ///      Only callable by the owner.
    /// @param transformerDeployer The address of the trusted deployer for transformers.
    function setTransformerDeployer(address transformerDeployer)
        external;
    /// @dev Deploy a new flash wallet instance and replace the current one with it.
    ///      Useful if we somehow break the current wallet instance.
    ///      Anyone can call this.
    /// @return wallet The new wallet instance.
    function createTransformWallet()
        external
        returns (IFlashWallet wallet);
    /// @dev Executes a series of transformations to convert an ERC20 `inputToken`
    ///      to an ERC20 `outputToken`.
    /// @param inputToken The token being provided by the sender.
    ///        If `0xeee...`, ETH is implied and should be provided with the call.`
    /// @param outputToken The token to be acquired by the sender.
    ///        `0xeee...` implies ETH.
    /// @param inputTokenAmount The amount of `inputToken` to take from the sender.
    /// @param minOutputTokenAmount The minimum amount of `outputToken` the sender
    ///        must receive for the entire transformation to succeed.
    /// @param transformations The transformations to execute on the token balance(s)
    ///        in sequence.
    /// @return outputTokenAmount The amount of `outputToken` received by the sender.
    function transformERC20(
        IERC20TokenV06 inputToken,
        IERC20TokenV06 outputToken,
        uint256 inputTokenAmount,
        uint256 minOutputTokenAmount,
        Transformation[] calldata transformations
    )
        external
        payable
        returns (uint256 outputTokenAmount);
    /// @dev Internal version of `transformERC20()`. Only callable from within.
    /// @param callDataHash Hash of the ingress calldata.
    /// @param taker The taker address.
    /// @param inputToken The token being provided by the taker.
    ///        If `0xeee...`, ETH is implied and should be provided with the call.`
    /// @param outputToken The token to be acquired by the taker.
    ///        `0xeee...` implies ETH.
    /// @param inputTokenAmount The amount of `inputToken` to take from the taker.
    /// @param minOutputTokenAmount The minimum amount of `outputToken` the taker
    ///        must receive for the entire transformation to succeed.
    /// @param transformations The transformations to execute on the token balance(s)
    ///        in sequence.
    /// @return outputTokenAmount The amount of `outputToken` received by the taker.
    function _transformERC20(
        bytes32 callDataHash,
        address payable taker,
        IERC20TokenV06 inputToken,
        IERC20TokenV06 outputToken,
        uint256 inputTokenAmount,
        uint256 minOutputTokenAmount,
        Transformation[] calldata transformations
    )
        external
        payable
        returns (uint256 outputTokenAmount);
    /// @dev Return the current wallet instance that will serve as the execution
    ///      context for transformations.
    /// @return wallet The wallet instance.
    function getTransformWallet()
        external
        view
        returns (IFlashWallet wallet);
    /// @dev Return the allowed deployer for transformers.
    /// @return deployer The transform deployer address.
    function getTransformerDeployer()
        external
        view
        returns (address deployer);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
/// @dev A transformation callback used in `TransformERC20.transformERC20()`.
interface IERC20Transformer {
    /// @dev Called from `TransformERC20.transformERC20()`. This will be
    ///      delegatecalled in the context of the FlashWallet instance being used.
    /// @param callDataHash The hash of the `TransformERC20.transformERC20()` calldata.
    /// @param taker The taker address (caller of `TransformERC20.transformERC20()`).
    /// @param data Arbitrary data to pass to the transformer.
    /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
    function transform(
        bytes32 callDataHash,
        address payable taker,
        bytes calldata data
    )
        external
        returns (bytes4 success);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../fixins/FixinCommon.sol";
import "../errors/LibOwnableRichErrors.sol";
import "../storage/LibOwnableStorage.sol";
import "../migrations/LibBootstrap.sol";
import "../migrations/LibMigrate.sol";
import "./IFeature.sol";
import "./IOwnable.sol";
import "./SimpleFunctionRegistry.sol";
/// @dev Owner management features.
contract Ownable is
    IFeature,
    IOwnable,
    FixinCommon
{
    // solhint-disable
    /// @dev Name of this feature.
    string public constant override FEATURE_NAME = "Ownable";
    /// @dev Version of this feature.
    uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 0, 0);
    /// @dev The deployed address of this contract.
    address immutable private _implementation;
    // solhint-enable
    using LibRichErrorsV06 for bytes;
    constructor() public {
        _implementation = address(this);
    }
    /// @dev Initializes this feature. The intial owner will be set to this (ZeroEx)
    ///      to allow the bootstrappers to call `extend()`. Ownership should be
    ///      transferred to the real owner by the bootstrapper after
    ///      bootstrapping is complete.
    /// @return success Magic bytes if successful.
    function bootstrap() external returns (bytes4 success) {
        // Set the owner to ourselves to allow bootstrappers to call `extend()`.
        LibOwnableStorage.getStorage().owner = address(this);
        // Register feature functions.
        SimpleFunctionRegistry(address(this))._extendSelf(this.transferOwnership.selector, _implementation);
        SimpleFunctionRegistry(address(this))._extendSelf(this.owner.selector, _implementation);
        SimpleFunctionRegistry(address(this))._extendSelf(this.migrate.selector, _implementation);
        return LibBootstrap.BOOTSTRAP_SUCCESS;
    }
    /// @dev Change the owner of this contract.
    ///      Only directly callable by the owner.
    /// @param newOwner New owner address.
    function transferOwnership(address newOwner)
        external
        override
        onlyOwner
    {
        LibOwnableStorage.Storage storage proxyStor = LibOwnableStorage.getStorage();
        if (newOwner == address(0)) {
            LibOwnableRichErrors.TransferOwnerToZeroError().rrevert();
        } else {
            proxyStor.owner = newOwner;
            emit OwnershipTransferred(msg.sender, newOwner);
        }
    }
    /// @dev Execute a migration function in the context of the ZeroEx contract.
    ///      The result of the function being called should be the magic bytes
    ///      0x2c64c5ef (`keccack('MIGRATE_SUCCESS')`). Only callable by the owner.
    ///      Temporarily sets the owner to ourselves so we can perform admin functions.
    ///      Before returning, the owner will be set to `newOwner`.
    /// @param target The migrator contract address.
    /// @param data The call data.
    /// @param newOwner The address of the new owner.
    function migrate(address target, bytes calldata data, address newOwner)
        external
        override
        onlyOwner
    {
        if (newOwner == address(0)) {
            LibOwnableRichErrors.TransferOwnerToZeroError().rrevert();
        }
        LibOwnableStorage.Storage storage stor = LibOwnableStorage.getStorage();
        // The owner will be temporarily set to `address(this)` inside the call.
        stor.owner = address(this);
        // Perform the migration.
        LibMigrate.delegatecallMigrateFunction(target, data);
        // Update the owner.
        stor.owner = newOwner;
        emit Migrated(msg.sender, target, newOwner);
    }
    /// @dev Get the owner of this contract.
    /// @return owner_ The owner of this contract.
    function owner() external override view returns (address owner_) {
        return LibOwnableStorage.getStorage().owner;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../errors/LibCommonRichErrors.sol";
import "../errors/LibOwnableRichErrors.sol";
import "../features/IOwnable.sol";
/// @dev Common feature utilities.
contract FixinCommon {
    using LibRichErrorsV06 for bytes;
    /// @dev The caller must be this contract.
    modifier onlySelf() virtual {
        if (msg.sender != address(this)) {
            LibCommonRichErrors.OnlyCallableBySelfError(msg.sender).rrevert();
        }
        _;
    }
    /// @dev The caller of this function must be the owner.
    modifier onlyOwner() virtual {
        {
            address owner = IOwnable(address(this)).owner();
            if (msg.sender != owner) {
                LibOwnableRichErrors.OnlyOwnerError(
                    msg.sender,
                    owner
                ).rrevert();
            }
        }
        _;
    }
    /// @dev Encode a feature version as a `uint256`.
    /// @param major The major version number of the feature.
    /// @param minor The minor version number of the feature.
    /// @param revision The revision number of the feature.
    /// @return encodedVersion The encoded version number.
    function _encodeVersion(uint32 major, uint32 minor, uint32 revision)
        internal
        pure
        returns (uint256 encodedVersion)
    {
        return (major << 64) | (minor << 32) | revision;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./LibStorage.sol";
/// @dev Storage helpers for the `Ownable` feature.
library LibOwnableStorage {
    /// @dev Storage bucket for this feature.
    struct Storage {
        // The owner of this contract.
        address owner;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        uint256 storageSlot = LibStorage.getStorageSlot(
            LibStorage.StorageId.Ownable
        );
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly { stor_slot := storageSlot }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../errors/LibOwnableRichErrors.sol";
library LibMigrate {
    /// @dev Magic bytes returned by a migrator to indicate success.
    ///      This is `keccack('MIGRATE_SUCCESS')`.
    bytes4 internal constant MIGRATE_SUCCESS = 0x2c64c5ef;
    using LibRichErrorsV06 for bytes;
    /// @dev Perform a delegatecall and ensure it returns the magic bytes.
    /// @param target The call target.
    /// @param data The call data.
    function delegatecallMigrateFunction(
        address target,
        bytes memory data
    )
        internal
    {
        (bool success, bytes memory resultData) = target.delegatecall(data);
        if (!success ||
            resultData.length != 32 ||
            abi.decode(resultData, (bytes4)) != MIGRATE_SUCCESS)
        {
            LibOwnableRichErrors.MigrateCallFailedError(target, resultData).rrevert();
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../fixins/FixinCommon.sol";
import "../storage/LibProxyStorage.sol";
import "../storage/LibSimpleFunctionRegistryStorage.sol";
import "../errors/LibSimpleFunctionRegistryRichErrors.sol";
import "../migrations/LibBootstrap.sol";
import "./IFeature.sol";
import "./ISimpleFunctionRegistry.sol";
/// @dev Basic registry management features.
contract SimpleFunctionRegistry is
    IFeature,
    ISimpleFunctionRegistry,
    FixinCommon
{
    // solhint-disable
    /// @dev Name of this feature.
    string public constant override FEATURE_NAME = "SimpleFunctionRegistry";
    /// @dev Version of this feature.
    uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 0, 0);
    /// @dev The deployed address of this contract.
    address private immutable _implementation;
    // solhint-enable
    using LibRichErrorsV06 for bytes;
    constructor() public {
        _implementation = address(this);
    }
    /// @dev Initializes this feature, registering its own functions.
    /// @return success Magic bytes if successful.
    function bootstrap()
        external
        returns (bytes4 success)
    {
        // Register the registration functions (inception vibes).
        _extend(this.extend.selector, _implementation);
        _extend(this._extendSelf.selector, _implementation);
        // Register the rollback function.
        _extend(this.rollback.selector, _implementation);
        // Register getters.
        _extend(this.getRollbackLength.selector, _implementation);
        _extend(this.getRollbackEntryAtIndex.selector, _implementation);
        return LibBootstrap.BOOTSTRAP_SUCCESS;
    }
    /// @dev Roll back to a prior implementation of a function.
    ///      Only directly callable by an authority.
    /// @param selector The function selector.
    /// @param targetImpl The address of an older implementation of the function.
    function rollback(bytes4 selector, address targetImpl)
        external
        override
        onlyOwner
    {
        (
            LibSimpleFunctionRegistryStorage.Storage storage stor,
            LibProxyStorage.Storage storage proxyStor
        ) = _getStorages();
        address currentImpl = proxyStor.impls[selector];
        if (currentImpl == targetImpl) {
            // Do nothing if already at targetImpl.
            return;
        }
        // Walk history backwards until we find the target implementation.
        address[] storage history = stor.implHistory[selector];
        uint256 i = history.length;
        for (; i > 0; --i) {
            address impl = history[i - 1];
            history.pop();
            if (impl == targetImpl) {
                break;
            }
        }
        if (i == 0) {
            LibSimpleFunctionRegistryRichErrors.NotInRollbackHistoryError(
                selector,
                targetImpl
            ).rrevert();
        }
        proxyStor.impls[selector] = targetImpl;
        emit ProxyFunctionUpdated(selector, currentImpl, targetImpl);
    }
    /// @dev Register or replace a function.
    ///      Only directly callable by an authority.
    /// @param selector The function selector.
    /// @param impl The implementation contract for the function.
    function extend(bytes4 selector, address impl)
        external
        override
        onlyOwner
    {
        _extend(selector, impl);
    }
    /// @dev Register or replace a function.
    ///      Only callable from within.
    ///      This function is only used during the bootstrap process and
    ///      should be deregistered by the deployer after bootstrapping is
    ///      complete.
    /// @param selector The function selector.
    /// @param impl The implementation contract for the function.
    function _extendSelf(bytes4 selector, address impl)
        external
        onlySelf
    {
        _extend(selector, impl);
    }
    /// @dev Retrieve the length of the rollback history for a function.
    /// @param selector The function selector.
    /// @return rollbackLength The number of items in the rollback history for
    ///         the function.
    function getRollbackLength(bytes4 selector)
        external
        override
        view
        returns (uint256 rollbackLength)
    {
        return LibSimpleFunctionRegistryStorage.getStorage().implHistory[selector].length;
    }
    /// @dev Retrieve an entry in the rollback history for a function.
    /// @param selector The function selector.
    /// @param idx The index in the rollback history.
    /// @return impl An implementation address for the function at
    ///         index `idx`.
    function getRollbackEntryAtIndex(bytes4 selector, uint256 idx)
        external
        override
        view
        returns (address impl)
    {
        return LibSimpleFunctionRegistryStorage.getStorage().implHistory[selector][idx];
    }
    /// @dev Register or replace a function.
    /// @param selector The function selector.
    /// @param impl The implementation contract for the function.
    function _extend(bytes4 selector, address impl)
        private
    {
        (
            LibSimpleFunctionRegistryStorage.Storage storage stor,
            LibProxyStorage.Storage storage proxyStor
        ) = _getStorages();
        address oldImpl = proxyStor.impls[selector];
        address[] storage history = stor.implHistory[selector];
        history.push(oldImpl);
        proxyStor.impls[selector] = impl;
        emit ProxyFunctionUpdated(selector, oldImpl, impl);
    }
    /// @dev Get the storage buckets for this feature and the proxy.
    /// @return stor Storage bucket for this feature.
    /// @return proxyStor age bucket for the proxy.
    function _getStorages()
        private
        pure
        returns (
            LibSimpleFunctionRegistryStorage.Storage storage stor,
            LibProxyStorage.Storage storage proxyStor
        )
    {
        return (
            LibSimpleFunctionRegistryStorage.getStorage(),
            LibProxyStorage.getStorage()
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./LibStorage.sol";
/// @dev Storage helpers for the `SimpleFunctionRegistry` feature.
library LibSimpleFunctionRegistryStorage {
    /// @dev Storage bucket for this feature.
    struct Storage {
        // Mapping of function selector -> implementation history.
        mapping(bytes4 => address[]) implHistory;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        uint256 storageSlot = LibStorage.getStorageSlot(
            LibStorage.StorageId.SimpleFunctionRegistry
        );
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly { stor_slot := storageSlot }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
import "../errors/LibSpenderRichErrors.sol";
import "../fixins/FixinCommon.sol";
import "../migrations/LibMigrate.sol";
import "../external/IAllowanceTarget.sol";
import "../storage/LibTokenSpenderStorage.sol";
import "./ITokenSpender.sol";
import "./IFeature.sol";
import "./ISimpleFunctionRegistry.sol";
/// @dev Feature that allows spending token allowances.
contract TokenSpender is
    IFeature,
    ITokenSpender,
    FixinCommon
{
    // solhint-disable
    /// @dev Name of this feature.
    string public constant override FEATURE_NAME = "TokenSpender";
    /// @dev Version of this feature.
    uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 0, 0);
    /// @dev The implementation address of this feature.
    address private immutable _implementation;
    // solhint-enable
    using LibRichErrorsV06 for bytes;
    constructor() public {
        _implementation = address(this);
    }
    /// @dev Initialize and register this feature. Should be delegatecalled
    ///      into during a `Migrate.migrate()`.
    /// @param allowanceTarget An `allowanceTarget` instance, configured to have
    ///        the ZeroeEx contract as an authority.
    /// @return success `MIGRATE_SUCCESS` on success.
    function migrate(IAllowanceTarget allowanceTarget) external returns (bytes4 success) {
        LibTokenSpenderStorage.getStorage().allowanceTarget = allowanceTarget;
        ISimpleFunctionRegistry(address(this))
            .extend(this.getAllowanceTarget.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this._spendERC20Tokens.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this.getSpendableERC20BalanceOf.selector, _implementation);
        return LibMigrate.MIGRATE_SUCCESS;
    }
    /// @dev Transfers ERC20 tokens from `owner` to `to`. Only callable from within.
    /// @param token The token to spend.
    /// @param owner The owner of the tokens.
    /// @param to The recipient of the tokens.
    /// @param amount The amount of `token` to transfer.
    function _spendERC20Tokens(
        IERC20TokenV06 token,
        address owner,
        address to,
        uint256 amount
    )
        external
        override
        onlySelf
    {
        IAllowanceTarget spender = LibTokenSpenderStorage.getStorage().allowanceTarget;
        // Have the allowance target execute an ERC20 `transferFrom()`.
        (bool didSucceed, bytes memory resultData) = address(spender).call(
            abi.encodeWithSelector(
                IAllowanceTarget.executeCall.selector,
                address(token),
                abi.encodeWithSelector(
                    IERC20TokenV06.transferFrom.selector,
                    owner,
                    to,
                    amount
                )
            )
        );
        if (didSucceed) {
            resultData = abi.decode(resultData, (bytes));
        }
        if (!didSucceed || !LibERC20TokenV06.isSuccessfulResult(resultData)) {
            LibSpenderRichErrors.SpenderERC20TransferFromFailedError(
                address(token),
                owner,
                to,
                amount,
                resultData
            ).rrevert();
        }
    }
    /// @dev Gets the maximum amount of an ERC20 token `token` that can be
    ///      pulled from `owner` by the token spender.
    /// @param token The token to spend.
    /// @param owner The owner of the tokens.
    /// @return amount The amount of tokens that can be pulled.
    function getSpendableERC20BalanceOf(IERC20TokenV06 token, address owner)
        external
        override
        view
        returns (uint256 amount)
    {
        return LibSafeMathV06.min256(
            token.allowance(owner, address(LibTokenSpenderStorage.getStorage().allowanceTarget)),
            token.balanceOf(owner)
        );
    }
    /// @dev Get the address of the allowance target.
    /// @return target The target of token allowances.
    function getAllowanceTarget()
        external
        override
        view
        returns (address target)
    {
        return address(LibTokenSpenderStorage.getStorage().allowanceTarget);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./errors/LibRichErrorsV06.sol";
import "./errors/LibSafeMathRichErrorsV06.sol";
library LibSafeMathV06 {
    function safeMul(uint256 a, uint256 b)
        internal
        pure
        returns (uint256)
    {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        if (c / a != b) {
            LibRichErrorsV06.rrevert(LibSafeMathRichErrorsV06.Uint256BinOpError(
                LibSafeMathRichErrorsV06.BinOpErrorCodes.MULTIPLICATION_OVERFLOW,
                a,
                b
            ));
        }
        return c;
    }
    function safeDiv(uint256 a, uint256 b)
        internal
        pure
        returns (uint256)
    {
        if (b == 0) {
            LibRichErrorsV06.rrevert(LibSafeMathRichErrorsV06.Uint256BinOpError(
                LibSafeMathRichErrorsV06.BinOpErrorCodes.DIVISION_BY_ZERO,
                a,
                b
            ));
        }
        uint256 c = a / b;
        return c;
    }
    function safeSub(uint256 a, uint256 b)
        internal
        pure
        returns (uint256)
    {
        if (b > a) {
            LibRichErrorsV06.rrevert(LibSafeMathRichErrorsV06.Uint256BinOpError(
                LibSafeMathRichErrorsV06.BinOpErrorCodes.SUBTRACTION_UNDERFLOW,
                a,
                b
            ));
        }
        return a - b;
    }
    function safeAdd(uint256 a, uint256 b)
        internal
        pure
        returns (uint256)
    {
        uint256 c = a + b;
        if (c < a) {
            LibRichErrorsV06.rrevert(LibSafeMathRichErrorsV06.Uint256BinOpError(
                LibSafeMathRichErrorsV06.BinOpErrorCodes.ADDITION_OVERFLOW,
                a,
                b
            ));
        }
        return c;
    }
    function max256(uint256 a, uint256 b)
        internal
        pure
        returns (uint256)
    {
        return a >= b ? a : b;
    }
    function min256(uint256 a, uint256 b)
        internal
        pure
        returns (uint256)
    {
        return a < b ? a : b;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibSafeMathRichErrorsV06 {
    // bytes4(keccak256("Uint256BinOpError(uint8,uint256,uint256)"))
    bytes4 internal constant UINT256_BINOP_ERROR_SELECTOR =
        0xe946c1bb;
    // bytes4(keccak256("Uint256DowncastError(uint8,uint256)"))
    bytes4 internal constant UINT256_DOWNCAST_ERROR_SELECTOR =
        0xc996af7b;
    enum BinOpErrorCodes {
        ADDITION_OVERFLOW,
        MULTIPLICATION_OVERFLOW,
        SUBTRACTION_UNDERFLOW,
        DIVISION_BY_ZERO
    }
    enum DowncastErrorCodes {
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT32,
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT64,
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT96
    }
    // solhint-disable func-name-mixedcase
    function Uint256BinOpError(
        BinOpErrorCodes errorCode,
        uint256 a,
        uint256 b
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            UINT256_BINOP_ERROR_SELECTOR,
            errorCode,
            a,
            b
        );
    }
    function Uint256DowncastError(
        DowncastErrorCodes errorCode,
        uint256 a
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            UINT256_DOWNCAST_ERROR_SELECTOR,
            errorCode,
            a
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
import "./IERC20TokenV06.sol";
library LibERC20TokenV06 {
    bytes constant private DECIMALS_CALL_DATA = hex"313ce567";
    /// @dev Calls `IERC20TokenV06(token).approve()`.
    ///      Reverts if the result fails `isSuccessfulResult()` or the call reverts.
    /// @param token The address of the token contract.
    /// @param spender The address that receives an allowance.
    /// @param allowance The allowance to set.
    function compatApprove(
        IERC20TokenV06 token,
        address spender,
        uint256 allowance
    )
        internal
    {
        bytes memory callData = abi.encodeWithSelector(
            token.approve.selector,
            spender,
            allowance
        );
        _callWithOptionalBooleanResult(address(token), callData);
    }
    /// @dev Calls `IERC20TokenV06(token).approve()` and sets the allowance to the
    ///      maximum if the current approval is not already >= an amount.
    ///      Reverts if the result fails `isSuccessfulResult()` or the call reverts.
    /// @param token The address of the token contract.
    /// @param spender The address that receives an allowance.
    /// @param amount The minimum allowance needed.
    function approveIfBelow(
        IERC20TokenV06 token,
        address spender,
        uint256 amount
    )
        internal
    {
        if (token.allowance(address(this), spender) < amount) {
            compatApprove(token, spender, uint256(-1));
        }
    }
    /// @dev Calls `IERC20TokenV06(token).transfer()`.
    ///      Reverts if the result fails `isSuccessfulResult()` or the call reverts.
    /// @param token The address of the token contract.
    /// @param to The address that receives the tokens
    /// @param amount Number of tokens to transfer.
    function compatTransfer(
        IERC20TokenV06 token,
        address to,
        uint256 amount
    )
        internal
    {
        bytes memory callData = abi.encodeWithSelector(
            token.transfer.selector,
            to,
            amount
        );
        _callWithOptionalBooleanResult(address(token), callData);
    }
    /// @dev Calls `IERC20TokenV06(token).transferFrom()`.
    ///      Reverts if the result fails `isSuccessfulResult()` or the call reverts.
    /// @param token The address of the token contract.
    /// @param from The owner of the tokens.
    /// @param to The address that receives the tokens
    /// @param amount Number of tokens to transfer.
    function compatTransferFrom(
        IERC20TokenV06 token,
        address from,
        address to,
        uint256 amount
    )
        internal
    {
        bytes memory callData = abi.encodeWithSelector(
            token.transferFrom.selector,
            from,
            to,
            amount
        );
        _callWithOptionalBooleanResult(address(token), callData);
    }
    /// @dev Retrieves the number of decimals for a token.
    ///      Returns `18` if the call reverts.
    /// @param token The address of the token contract.
    /// @return tokenDecimals The number of decimals places for the token.
    function compatDecimals(IERC20TokenV06 token)
        internal
        view
        returns (uint8 tokenDecimals)
    {
        tokenDecimals = 18;
        (bool didSucceed, bytes memory resultData) = address(token).staticcall(DECIMALS_CALL_DATA);
        if (didSucceed && resultData.length == 32) {
            tokenDecimals = uint8(LibBytesV06.readUint256(resultData, 0));
        }
    }
    /// @dev Retrieves the allowance for a token, owner, and spender.
    ///      Returns `0` if the call reverts.
    /// @param token The address of the token contract.
    /// @param owner The owner of the tokens.
    /// @param spender The address the spender.
    /// @return allowance_ The allowance for a token, owner, and spender.
    function compatAllowance(IERC20TokenV06 token, address owner, address spender)
        internal
        view
        returns (uint256 allowance_)
    {
        (bool didSucceed, bytes memory resultData) = address(token).staticcall(
            abi.encodeWithSelector(
                token.allowance.selector,
                owner,
                spender
            )
        );
        if (didSucceed && resultData.length == 32) {
            allowance_ = LibBytesV06.readUint256(resultData, 0);
        }
    }
    /// @dev Retrieves the balance for a token owner.
    ///      Returns `0` if the call reverts.
    /// @param token The address of the token contract.
    /// @param owner The owner of the tokens.
    /// @return balance The token balance of an owner.
    function compatBalanceOf(IERC20TokenV06 token, address owner)
        internal
        view
        returns (uint256 balance)
    {
        (bool didSucceed, bytes memory resultData) = address(token).staticcall(
            abi.encodeWithSelector(
                token.balanceOf.selector,
                owner
            )
        );
        if (didSucceed && resultData.length == 32) {
            balance = LibBytesV06.readUint256(resultData, 0);
        }
    }
    /// @dev Check if the data returned by a non-static call to an ERC20 token
    ///      is a successful result. Supported functions are `transfer()`,
    ///      `transferFrom()`, and `approve()`.
    /// @param resultData The raw data returned by a non-static call to the ERC20 token.
    /// @return isSuccessful Whether the result data indicates success.
    function isSuccessfulResult(bytes memory resultData)
        internal
        pure
        returns (bool isSuccessful)
    {
        if (resultData.length == 0) {
            return true;
        }
        if (resultData.length == 32) {
            uint256 result = LibBytesV06.readUint256(resultData, 0);
            if (result == 1) {
                return true;
            }
        }
    }
    /// @dev Executes a call on address `target` with calldata `callData`
    ///      and asserts that either nothing was returned or a single boolean
    ///      was returned equal to `true`.
    /// @param target The call target.
    /// @param callData The abi-encoded call data.
    function _callWithOptionalBooleanResult(
        address target,
        bytes memory callData
    )
        private
    {
        (bool didSucceed, bytes memory resultData) = target.call(callData);
        if (didSucceed && isSuccessfulResult(resultData)) {
            return;
        }
        LibRichErrorsV06.rrevert(resultData);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./LibStorage.sol";
import "../external/IAllowanceTarget.sol";
/// @dev Storage helpers for the `TokenSpender` feature.
library LibTokenSpenderStorage {
    /// @dev Storage bucket for this feature.
    struct Storage {
        // Allowance target contract.
        IAllowanceTarget allowanceTarget;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        uint256 storageSlot = LibStorage.getStorageSlot(
            LibStorage.StorageId.TokenSpender
        );
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly { stor_slot := storageSlot }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "../errors/LibTransformERC20RichErrors.sol";
import "../fixins/FixinCommon.sol";
import "../migrations/LibMigrate.sol";
import "../external/IFlashWallet.sol";
import "../external/FlashWallet.sol";
import "../storage/LibTransformERC20Storage.sol";
import "../transformers/IERC20Transformer.sol";
import "../transformers/LibERC20Transformer.sol";
import "./ITransformERC20.sol";
import "./ITokenSpender.sol";
import "./IFeature.sol";
import "./ISimpleFunctionRegistry.sol";
/// @dev Feature to composably transform between ERC20 tokens.
contract TransformERC20 is
    IFeature,
    ITransformERC20,
    FixinCommon
{
    /// @dev Stack vars for `_transformERC20Private()`.
    struct TransformERC20PrivateState {
        IFlashWallet wallet;
        address transformerDeployer;
        uint256 takerOutputTokenBalanceBefore;
        uint256 takerOutputTokenBalanceAfter;
    }
    // solhint-disable
    /// @dev Name of this feature.
    string public constant override FEATURE_NAME = "TransformERC20";
    /// @dev Version of this feature.
    uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 0, 0);
    /// @dev The implementation address of this feature.
    address private immutable _implementation;
    // solhint-enable
    using LibSafeMathV06 for uint256;
    using LibRichErrorsV06 for bytes;
    constructor() public {
        _implementation = address(this);
    }
    /// @dev Initialize and register this feature.
    ///      Should be delegatecalled by `Migrate.migrate()`.
    /// @param transformerDeployer The trusted deployer for transformers.
    /// @return success `LibMigrate.SUCCESS` on success.
    function migrate(address transformerDeployer) external returns (bytes4 success) {
        ISimpleFunctionRegistry(address(this))
            .extend(this.getTransformerDeployer.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this.createTransformWallet.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this.getTransformWallet.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this.setTransformerDeployer.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this.transformERC20.selector, _implementation);
        ISimpleFunctionRegistry(address(this))
            .extend(this._transformERC20.selector, _implementation);
        createTransformWallet();
        LibTransformERC20Storage.getStorage().transformerDeployer = transformerDeployer;
        return LibMigrate.MIGRATE_SUCCESS;
    }
    /// @dev Replace the allowed deployer for transformers.
    ///      Only callable by the owner.
    /// @param transformerDeployer The address of the trusted deployer for transformers.
    function setTransformerDeployer(address transformerDeployer)
        external
        override
        onlyOwner
    {
        LibTransformERC20Storage.getStorage().transformerDeployer = transformerDeployer;
        emit TransformerDeployerUpdated(transformerDeployer);
    }
    /// @dev Return the allowed deployer for transformers.
    /// @return deployer The transform deployer address.
    function getTransformerDeployer()
        public
        override
        view
        returns (address deployer)
    {
        return LibTransformERC20Storage.getStorage().transformerDeployer;
    }
    /// @dev Deploy a new wallet instance and replace the current one with it.
    ///      Useful if we somehow break the current wallet instance.
    ///      Anyone can call this.
    /// @return wallet The new wallet instance.
    function createTransformWallet()
        public
        override
        returns (IFlashWallet wallet)
    {
        wallet = new FlashWallet();
        LibTransformERC20Storage.getStorage().wallet = wallet;
    }
    /// @dev Executes a series of transformations to convert an ERC20 `inputToken`
    ///      to an ERC20 `outputToken`.
    /// @param inputToken The token being provided by the sender.
    ///        If `0xeee...`, ETH is implied and should be provided with the call.`
    /// @param outputToken The token to be acquired by the sender.
    ///        `0xeee...` implies ETH.
    /// @param inputTokenAmount The amount of `inputToken` to take from the sender.
    ///        If set to `uint256(-1)`, the entire spendable balance of the taker
    ///        will be solt.
    /// @param minOutputTokenAmount The minimum amount of `outputToken` the sender
    ///        must receive for the entire transformation to succeed. If set to zero,
    ///        the minimum output token transfer will not be asserted.
    /// @param transformations The transformations to execute on the token balance(s)
    ///        in sequence.
    /// @return outputTokenAmount The amount of `outputToken` received by the sender.
    function transformERC20(
        IERC20TokenV06 inputToken,
        IERC20TokenV06 outputToken,
        uint256 inputTokenAmount,
        uint256 minOutputTokenAmount,
        Transformation[] memory transformations
    )
        public
        override
        payable
        returns (uint256 outputTokenAmount)
    {
        return _transformERC20Private(
            keccak256(msg.data),
            msg.sender,
            inputToken,
            outputToken,
            inputTokenAmount,
            minOutputTokenAmount,
            transformations
        );
    }
    /// @dev Internal version of `transformERC20()`. Only callable from within.
    /// @param callDataHash Hash of the ingress calldata.
    /// @param taker The taker address.
    /// @param inputToken The token being provided by the taker.
    ///        If `0xeee...`, ETH is implied and should be provided with the call.`
    /// @param outputToken The token to be acquired by the taker.
    ///        `0xeee...` implies ETH.
    /// @param inputTokenAmount The amount of `inputToken` to take from the taker.
    ///        If set to `uint256(-1)`, the entire spendable balance of the taker
    ///        will be solt.
    /// @param minOutputTokenAmount The minimum amount of `outputToken` the taker
    ///        must receive for the entire transformation to succeed. If set to zero,
    ///        the minimum output token transfer will not be asserted.
    /// @param transformations The transformations to execute on the token balance(s)
    ///        in sequence.
    /// @return outputTokenAmount The amount of `outputToken` received by the taker.
    function _transformERC20(
        bytes32 callDataHash,
        address payable taker,
        IERC20TokenV06 inputToken,
        IERC20TokenV06 outputToken,
        uint256 inputTokenAmount,
        uint256 minOutputTokenAmount,
        Transformation[] memory transformations
    )
        public
        override
        payable
        onlySelf
        returns (uint256 outputTokenAmount)
    {
        return _transformERC20Private(
            callDataHash,
            taker,
            inputToken,
            outputToken,
            inputTokenAmount,
            minOutputTokenAmount,
            transformations
        );
    }
    /// @dev Private version of `transformERC20()`.
    /// @param callDataHash Hash of the ingress calldata.
    /// @param taker The taker address.
    /// @param inputToken The token being provided by the taker.
    ///        If `0xeee...`, ETH is implied and should be provided with the call.`
    /// @param outputToken The token to be acquired by the taker.
    ///        `0xeee...` implies ETH.
    /// @param inputTokenAmount The amount of `inputToken` to take from the taker.
    ///        If set to `uint256(-1)`, the entire spendable balance of the taker
    ///        will be solt.
    /// @param minOutputTokenAmount The minimum amount of `outputToken` the taker
    ///        must receive for the entire transformation to succeed. If set to zero,
    ///        the minimum output token transfer will not be asserted.
    /// @param transformations The transformations to execute on the token balance(s)
    ///        in sequence.
    /// @return outputTokenAmount The amount of `outputToken` received by the taker.
    function _transformERC20Private(
        bytes32 callDataHash,
        address payable taker,
        IERC20TokenV06 inputToken,
        IERC20TokenV06 outputToken,
        uint256 inputTokenAmount,
        uint256 minOutputTokenAmount,
        Transformation[] memory transformations
    )
        private
        returns (uint256 outputTokenAmount)
    {
        // If the input token amount is -1, transform the taker's entire
        // spendable balance.
        if (inputTokenAmount == uint256(-1)) {
            inputTokenAmount = ITokenSpender(address(this))
                .getSpendableERC20BalanceOf(inputToken, taker);
        }
        TransformERC20PrivateState memory state;
        state.wallet = getTransformWallet();
        state.transformerDeployer = getTransformerDeployer();
        // Remember the initial output token balance of the taker.
        state.takerOutputTokenBalanceBefore =
            LibERC20Transformer.getTokenBalanceOf(outputToken, taker);
        // Pull input tokens from the taker to the wallet and transfer attached ETH.
        _transferInputTokensAndAttachedEth(
            inputToken,
            taker,
            address(state.wallet),
            inputTokenAmount
        );
        // Perform transformations.
        for (uint256 i = 0; i < transformations.length; ++i) {
            _executeTransformation(
                state.wallet,
                transformations[i],
                state.transformerDeployer,
                taker,
                callDataHash
            );
        }
        // Compute how much output token has been transferred to the taker.
        state.takerOutputTokenBalanceAfter =
            LibERC20Transformer.getTokenBalanceOf(outputToken, taker);
        if (state.takerOutputTokenBalanceAfter > state.takerOutputTokenBalanceBefore) {
            outputTokenAmount = state.takerOutputTokenBalanceAfter.safeSub(
                state.takerOutputTokenBalanceBefore
            );
        } else if (state.takerOutputTokenBalanceAfter < state.takerOutputTokenBalanceBefore) {
            LibTransformERC20RichErrors.NegativeTransformERC20OutputError(
                address(outputToken),
                state.takerOutputTokenBalanceBefore - state.takerOutputTokenBalanceAfter
            ).rrevert();
        }
        // Ensure enough output token has been sent to the taker.
        if (outputTokenAmount < minOutputTokenAmount) {
            LibTransformERC20RichErrors.IncompleteTransformERC20Error(
                address(outputToken),
                outputTokenAmount,
                minOutputTokenAmount
            ).rrevert();
        }
        // Emit an event.
        emit TransformedERC20(
            taker,
            address(inputToken),
            address(outputToken),
            inputTokenAmount,
            outputTokenAmount
        );
    }
    /// @dev Return the current wallet instance that will serve as the execution
    ///      context for transformations.
    /// @return wallet The wallet instance.
    function getTransformWallet()
        public
        override
        view
        returns (IFlashWallet wallet)
    {
        return LibTransformERC20Storage.getStorage().wallet;
    }
    /// @dev Transfer input tokens from the taker and any attached ETH to `to`
    /// @param inputToken The token to pull from the taker.
    /// @param from The from (taker) address.
    /// @param to The recipient of tokens and ETH.
    /// @param amount Amount of `inputToken` tokens to transfer.
    function _transferInputTokensAndAttachedEth(
        IERC20TokenV06 inputToken,
        address from,
        address payable to,
        uint256 amount
    )
        private
    {
        // Transfer any attached ETH.
        if (msg.value != 0) {
            to.transfer(msg.value);
        }
        // Transfer input tokens.
        if (!LibERC20Transformer.isTokenETH(inputToken)) {
            // Token is not ETH, so pull ERC20 tokens.
            ITokenSpender(address(this))._spendERC20Tokens(
                inputToken,
                from,
                to,
                amount
            );
        } else if (msg.value < amount) {
             // Token is ETH, so the caller must attach enough ETH to the call.
            LibTransformERC20RichErrors.InsufficientEthAttachedError(
                msg.value,
                amount
            ).rrevert();
        }
    }
    /// @dev Executs a transformer in the context of `wallet`.
    /// @param wallet The wallet instance.
    /// @param transformation The transformation.
    /// @param transformerDeployer The address of the transformer deployer.
    /// @param taker The taker address.
    /// @param callDataHash Hash of the calldata.
    function _executeTransformation(
        IFlashWallet wallet,
        Transformation memory transformation,
        address transformerDeployer,
        address payable taker,
        bytes32 callDataHash
    )
        private
    {
        // Derive the transformer address from the deployment nonce.
        address payable transformer = LibERC20Transformer.getDeployedAddress(
            transformerDeployer,
            transformation.deploymentNonce
        );
        // Call `transformer.transform()` as the wallet.
        bytes memory resultData = wallet.executeDelegateCall(
            // The call target.
            transformer,
            // Call data.
            abi.encodeWithSelector(
                IERC20Transformer.transform.selector,
                callDataHash,
                taker,
                transformation.data
            )
        );
        // Ensure the transformer returned the magic bytes.
        if (resultData.length != 32 ||
            abi.decode(resultData, (bytes4)) != LibERC20Transformer.TRANSFORMER_SUCCESS
        ) {
            LibTransformERC20RichErrors.TransformerFailedError(
                transformer,
                transformation.data,
                resultData
            ).rrevert();
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./LibStorage.sol";
import "../external/IFlashWallet.sol";
/// @dev Storage helpers for the `TokenSpender` feature.
library LibTransformERC20Storage {
    /// @dev Storage bucket for this feature.
    struct Storage {
        // The current wallet instance.
        IFlashWallet wallet;
        // The transformer deployer address.
        address transformerDeployer;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        uint256 storageSlot = LibStorage.getStorageSlot(
            LibStorage.StorageId.TransformERC20
        );
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly { stor_slot := storageSlot }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
library LibERC20Transformer {
    using LibERC20TokenV06 for IERC20TokenV06;
    /// @dev ETH pseudo-token address.
    address constant internal ETH_TOKEN_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    /// @dev Return value indicating success in `IERC20Transformer.transform()`.
    ///      This is just `keccak256('TRANSFORMER_SUCCESS')`.
    bytes4 constant internal TRANSFORMER_SUCCESS = 0x13c9929e;
    /// @dev Transfer ERC20 tokens and ETH.
    /// @param token An ERC20 or the ETH pseudo-token address (`ETH_TOKEN_ADDRESS`).
    /// @param to The recipient.
    /// @param amount The transfer amount.
    function transformerTransfer(
        IERC20TokenV06 token,
        address payable to,
        uint256 amount
    )
        internal
    {
        if (isTokenETH(token)) {
            to.transfer(amount);
        } else {
            token.compatTransfer(to, amount);
        }
    }
    /// @dev Check if a token is the ETH pseudo-token.
    /// @param token The token to check.
    /// @return isETH `true` if the token is the ETH pseudo-token.
    function isTokenETH(IERC20TokenV06 token)
        internal
        pure
        returns (bool isETH)
    {
        return address(token) == ETH_TOKEN_ADDRESS;
    }
    /// @dev Check the balance of an ERC20 token or ETH.
    /// @param token An ERC20 or the ETH pseudo-token address (`ETH_TOKEN_ADDRESS`).
    /// @param owner Holder of the tokens.
    /// @return tokenBalance The balance of `owner`.
    function getTokenBalanceOf(IERC20TokenV06 token, address owner)
        internal
        view
        returns (uint256 tokenBalance)
    {
        if (isTokenETH(token)) {
            return owner.balance;
        }
        return token.balanceOf(owner);
    }
    /// @dev RLP-encode a 32-bit or less account nonce.
    /// @param nonce A positive integer in the range 0 <= nonce < 2^32.
    /// @return rlpNonce The RLP encoding.
    function rlpEncodeNonce(uint32 nonce)
        internal
        pure
        returns (bytes memory rlpNonce)
    {
        // See https://github.com/ethereum/wiki/wiki/RLP for RLP encoding rules.
        if (nonce == 0) {
            rlpNonce = new bytes(1);
            rlpNonce[0] = 0x80;
        } else if (nonce < 0x80) {
            rlpNonce = new bytes(1);
            rlpNonce[0] = byte(uint8(nonce));
        } else if (nonce <= 0xFF) {
            rlpNonce = new bytes(2);
            rlpNonce[0] = 0x81;
            rlpNonce[1] = byte(uint8(nonce));
        } else if (nonce <= 0xFFFF) {
            rlpNonce = new bytes(3);
            rlpNonce[0] = 0x82;
            rlpNonce[1] = byte(uint8((nonce & 0xFF00) >> 8));
            rlpNonce[2] = byte(uint8(nonce));
        } else if (nonce <= 0xFFFFFF) {
            rlpNonce = new bytes(4);
            rlpNonce[0] = 0x83;
            rlpNonce[1] = byte(uint8((nonce & 0xFF0000) >> 16));
            rlpNonce[2] = byte(uint8((nonce & 0xFF00) >> 8));
            rlpNonce[3] = byte(uint8(nonce));
        } else {
            rlpNonce = new bytes(5);
            rlpNonce[0] = 0x84;
            rlpNonce[1] = byte(uint8((nonce & 0xFF000000) >> 24));
            rlpNonce[2] = byte(uint8((nonce & 0xFF0000) >> 16));
            rlpNonce[3] = byte(uint8((nonce & 0xFF00) >> 8));
            rlpNonce[4] = byte(uint8(nonce));
        }
    }
    /// @dev Compute the expected deployment address by `deployer` at
    ///      the nonce given by `deploymentNonce`.
    /// @param deployer The address of the deployer.
    /// @param deploymentNonce The nonce that the deployer had when deploying
    ///        a contract.
    /// @return deploymentAddress The deployment address.
    function getDeployedAddress(address deployer, uint32 deploymentNonce)
        internal
        pure
        returns (address payable deploymentAddress)
    {
        // The address of if a deployed contract is the lower 20 bytes of the
        // hash of the RLP-encoded deployer's account address + account nonce.
        // See: https://ethereum.stackexchange.com/questions/760/how-is-the-address-of-an-ethereum-contract-computed
        bytes memory rlpNonce = rlpEncodeNonce(deploymentNonce);
        return address(uint160(uint256(keccak256(abi.encodePacked(
            byte(uint8(0xC0 + 21 + rlpNonce.length)),
            byte(uint8(0x80 + 20)),
            deployer,
            rlpNonce
        )))));
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../ZeroEx.sol";
import "../features/IOwnable.sol";
import "../features/TokenSpender.sol";
import "../features/TransformERC20.sol";
import "../external/AllowanceTarget.sol";
import "./InitialMigration.sol";
/// @dev A contract for deploying and configuring the full ZeroEx contract.
contract FullMigration {
    // solhint-disable no-empty-blocks,indent
    /// @dev Features to add the the proxy contract.
    struct Features {
        SimpleFunctionRegistry registry;
        Ownable ownable;
        TokenSpender tokenSpender;
        TransformERC20 transformERC20;
    }
    /// @dev Parameters needed to initialize features.
    struct MigrateOpts {
        address transformerDeployer;
    }
    /// @dev The allowed caller of `deploy()`.
    address public immutable deployer;
    /// @dev The initial migration contract.
    InitialMigration private _initialMigration;
    /// @dev Instantiate this contract and set the allowed caller of `deploy()`
    ///      to `deployer`.
    /// @param deployer_ The allowed caller of `deploy()`.
    constructor(address payable deployer_)
        public
    {
        deployer = deployer_;
        // Create an initial migration contract with this contract set to the
        // allowed deployer.
        _initialMigration = new InitialMigration(address(this));
    }
    /// @dev Deploy the `ZeroEx` contract with the full feature set,
    ///      transfer ownership to `owner`, then self-destruct.
    /// @param owner The owner of the contract.
    /// @param features Features to add to the proxy.
    /// @return zeroEx The deployed and configured `ZeroEx` contract.
    /// @param migrateOpts Parameters needed to initialize features.
    function deploy(
        address payable owner,
        Features memory features,
        MigrateOpts memory migrateOpts
    )
        public
        returns (ZeroEx zeroEx)
    {
        require(msg.sender == deployer, "FullMigration/INVALID_SENDER");
        // Perform the initial migration with the owner set to this contract.
        zeroEx = _initialMigration.deploy(
            address(uint160(address(this))),
            InitialMigration.BootstrapFeatures({
                registry: features.registry,
                ownable: features.ownable
            })
        );
        // Add features.
        _addFeatures(zeroEx, owner, features, migrateOpts);
        // Transfer ownership to the real owner.
        IOwnable(address(zeroEx)).transferOwnership(owner);
        // Self-destruct.
        this.die(owner);
    }
    /// @dev Destroy this contract. Only callable from ourselves (from `deploy()`).
    /// @param ethRecipient Receiver of any ETH in this contract.
    function die(address payable ethRecipient)
        external
        virtual
    {
        require(msg.sender == address(this), "FullMigration/INVALID_SENDER");
        // This contract should not hold any funds but we send
        // them to the ethRecipient just in case.
        selfdestruct(ethRecipient);
    }
    /// @dev Deploy and register features to the ZeroEx contract.
    /// @param zeroEx The bootstrapped ZeroEx contract.
    /// @param owner The ultimate owner of the ZeroEx contract.
    /// @param features Features to add to the proxy.
    /// @param migrateOpts Parameters needed to initialize features.
    function _addFeatures(
        ZeroEx zeroEx,
        address owner,
        Features memory features,
        MigrateOpts memory migrateOpts
    )
        private
    {
        IOwnable ownable = IOwnable(address(zeroEx));
        // TokenSpender
        {
            // Create the allowance target.
            AllowanceTarget allowanceTarget = new AllowanceTarget();
            // Let the ZeroEx contract use the allowance target.
            allowanceTarget.addAuthorizedAddress(address(zeroEx));
            // Transfer ownership of the allowance target to the (real) owner.
            allowanceTarget.transferOwnership(owner);
            // Register the feature.
            ownable.migrate(
                address(features.tokenSpender),
                abi.encodeWithSelector(
                    TokenSpender.migrate.selector,
                    allowanceTarget
                ),
                address(this)
            );
        }
        // TransformERC20
        {
            // Register the feature.
            ownable.migrate(
                address(features.transformERC20),
                abi.encodeWithSelector(
                    TransformERC20.migrate.selector,
                    migrateOpts.transformerDeployer
                ),
                address(this)
            );
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../ZeroEx.sol";
import "../features/IBootstrap.sol";
import "../features/SimpleFunctionRegistry.sol";
import "../features/Ownable.sol";
import "./LibBootstrap.sol";
/// @dev A contract for deploying and configuring a minimal ZeroEx contract.
contract InitialMigration {
    /// @dev Features to bootstrap into the the proxy contract.
    struct BootstrapFeatures {
        SimpleFunctionRegistry registry;
        Ownable ownable;
    }
    /// @dev The allowed caller of `deploy()`. In production, this would be
    ///      the governor.
    address public immutable deployer;
    /// @dev The real address of this contract.
    address private immutable _implementation;
    /// @dev Instantiate this contract and set the allowed caller of `deploy()`
    ///      to `deployer_`.
    /// @param deployer_ The allowed caller of `deploy()`.
    constructor(address deployer_) public {
        deployer = deployer_;
        _implementation = address(this);
    }
    /// @dev Deploy the `ZeroEx` contract with the minimum feature set,
    ///      transfers ownership to `owner`, then self-destructs.
    ///      Only callable by `deployer` set in the contstructor.
    /// @param owner The owner of the contract.
    /// @param features Features to bootstrap into the proxy.
    /// @return zeroEx The deployed and configured `ZeroEx` contract.
    function deploy(address payable owner, BootstrapFeatures memory features)
        public
        virtual
        returns (ZeroEx zeroEx)
    {
        // Must be called by the allowed deployer.
        require(msg.sender == deployer, "InitialMigration/INVALID_SENDER");
        // Deploy the ZeroEx contract, setting ourselves as the bootstrapper.
        zeroEx = new ZeroEx();
        // Bootstrap the initial feature set.
        IBootstrap(address(zeroEx)).bootstrap(
            address(this),
            abi.encodeWithSelector(this.bootstrap.selector, owner, features)
        );
        // Self-destruct. This contract should not hold any funds but we send
        // them to the owner just in case.
        this.die(owner);
    }
    /// @dev Sets up the initial state of the `ZeroEx` contract.
    ///      The `ZeroEx` contract will delegatecall into this function.
    /// @param owner The new owner of the ZeroEx contract.
    /// @param features Features to bootstrap into the proxy.
    /// @return success Magic bytes if successful.
    function bootstrap(address owner, BootstrapFeatures memory features)
        public
        virtual
        returns (bytes4 success)
    {
        // Deploy and migrate the initial features.
        // Order matters here.
        // Initialize Registry.
        LibBootstrap.delegatecallBootstrapFunction(
            address(features.registry),
            abi.encodeWithSelector(
                SimpleFunctionRegistry.bootstrap.selector
            )
        );
        // Initialize Ownable.
        LibBootstrap.delegatecallBootstrapFunction(
            address(features.ownable),
            abi.encodeWithSelector(
                Ownable.bootstrap.selector
            )
        );
        // De-register `SimpleFunctionRegistry._extendSelf`.
        SimpleFunctionRegistry(address(this)).rollback(
            SimpleFunctionRegistry._extendSelf.selector,
            address(0)
        );
        // Transfer ownership to the real owner.
        Ownable(address(this)).transferOwnership(owner);
        success = LibBootstrap.BOOTSTRAP_SUCCESS;
    }
    /// @dev Self-destructs this contract. Only callable by this contract.
    /// @param ethRecipient Who to transfer outstanding ETH to.
    function die(address payable ethRecipient) public virtual {
        require(msg.sender == _implementation, "InitialMigration/INVALID_SENDER");
        selfdestruct(ethRecipient);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
import "../errors/LibTransformERC20RichErrors.sol";
import "./Transformer.sol";
import "./LibERC20Transformer.sol";
/// @dev A transformer that transfers tokens to arbitrary addresses.
contract AffiliateFeeTransformer is
    Transformer
{
    // solhint-disable no-empty-blocks
    using LibRichErrorsV06 for bytes;
    using LibSafeMathV06 for uint256;
    using LibERC20Transformer for IERC20TokenV06;
    /// @dev Information for a single fee.
    struct TokenFee {
        // The token to transfer to `recipient`.
        IERC20TokenV06 token;
        // Amount of each `token` to transfer to `recipient`.
        // If `amount == uint256(-1)`, the entire balance of `token` will be
        // transferred.
        uint256 amount;
        // Recipient of `token`.
        address payable recipient;
    }
    uint256 private constant MAX_UINT256 = uint256(-1);
    /// @dev Create this contract.
    constructor()
        public
        Transformer()
    {}
    /// @dev Transfers tokens to recipients.
    /// @param data ABI-encoded `TokenFee[]`, indicating which tokens to transfer.
    /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
    function transform(
        bytes32, // callDataHash,
        address payable, // taker,
        bytes calldata data
    )
        external
        override
        returns (bytes4 success)
    {
        TokenFee[] memory fees = abi.decode(data, (TokenFee[]));
        // Transfer tokens to recipients.
        for (uint256 i = 0; i < fees.length; ++i) {
            uint256 amount = fees[i].amount;
            if (amount == MAX_UINT256) {
                amount = LibERC20Transformer.getTokenBalanceOf(fees[i].token, address(this));
            }
            if (amount != 0) {
                fees[i].token.transformerTransfer(fees[i].recipient, amount);
            }
        }
        return LibERC20Transformer.TRANSFORMER_SUCCESS;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../errors/LibTransformERC20RichErrors.sol";
import "./IERC20Transformer.sol";
/// @dev Abstract base class for transformers.
abstract contract Transformer is
    IERC20Transformer
{
    using LibRichErrorsV06 for bytes;
    /// @dev The address of the deployer.
    address public immutable deployer;
    /// @dev The original address of this contract.
    address private immutable _implementation;
    /// @dev Create this contract.
    constructor() public {
        deployer = msg.sender;
        _implementation = address(this);
    }
    /// @dev Destruct this contract. Only callable by the deployer and will not
    ///      succeed in the context of a delegatecall (from another contract).
    /// @param ethRecipient The recipient of ETH held in this contract.
    function die(address payable ethRecipient)
        external
        virtual
    {
        // Only the deployer can call this.
        if (msg.sender != deployer) {
            LibTransformERC20RichErrors
                .OnlyCallableByDeployerError(msg.sender, deployer)
                .rrevert();
        }
        // Must be executing our own context.
        if (address(this) != _implementation) {
            LibTransformERC20RichErrors
                .InvalidExecutionContextError(address(this), _implementation)
                .rrevert();
        }
        selfdestruct(ethRecipient);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibMathV06.sol";
import "../errors/LibTransformERC20RichErrors.sol";
import "../vendor/v3/IExchange.sol";
import "./Transformer.sol";
import "./LibERC20Transformer.sol";
/// @dev A transformer that fills an ERC20 market sell/buy quote.
contract FillQuoteTransformer is
    Transformer
{
    using LibERC20TokenV06 for IERC20TokenV06;
    using LibERC20Transformer for IERC20TokenV06;
    using LibSafeMathV06 for uint256;
    using LibRichErrorsV06 for bytes;
    /// @dev Whether we are performing a market sell or buy.
    enum Side {
        Sell,
        Buy
    }
    /// @dev Transform data to ABI-encode and pass into `transform()`.
    struct TransformData {
        // Whether we aer performing a market sell or buy.
        Side side;
        // The token being sold.
        // This should be an actual token, not the ETH pseudo-token.
        IERC20TokenV06 sellToken;
        // The token being bought.
        // This should be an actual token, not the ETH pseudo-token.
        IERC20TokenV06 buyToken;
        // The orders to fill.
        IExchange.Order[] orders;
        // Signatures for each respective order in `orders`.
        bytes[] signatures;
        // Maximum fill amount for each order. This may be shorter than the
        // number of orders, where missing entries will be treated as `uint256(-1)`.
        // For sells, this will be the maximum sell amount (taker asset).
        // For buys, this will be the maximum buy amount (maker asset).
        uint256[] maxOrderFillAmounts;
        // Amount of `sellToken` to sell or `buyToken` to buy.
        // For sells, this may be `uint256(-1)` to sell the entire balance of
        // `sellToken`.
        uint256 fillAmount;
    }
    /// @dev Results of a call to `_fillOrder()`.
    struct FillOrderResults {
        // The amount of taker tokens sold, according to balance checks.
        uint256 takerTokenSoldAmount;
        // The amount of maker tokens sold, according to balance checks.
        uint256 makerTokenBoughtAmount;
        // The amount of protocol fee paid.
        uint256 protocolFeePaid;
    }
    /// @dev The Exchange ERC20Proxy ID.
    bytes4 private constant ERC20_ASSET_PROXY_ID = 0xf47261b0;
    /// @dev Maximum uint256 value.
    uint256 private constant MAX_UINT256 = uint256(-1);
    /// @dev The Exchange contract.
    IExchange public immutable exchange;
    /// @dev The ERC20Proxy address.
    address public immutable erc20Proxy;
    /// @dev Create this contract.
    /// @param exchange_ The Exchange V3 instance.
    constructor(IExchange exchange_)
        public
        Transformer()
    {
        exchange = exchange_;
        erc20Proxy = exchange_.getAssetProxy(ERC20_ASSET_PROXY_ID);
    }
    /// @dev Sell this contract's entire balance of of `sellToken` in exchange
    ///      for `buyToken` by filling `orders`. Protocol fees should be attached
    ///      to this call. `buyToken` and excess ETH will be transferred back to the caller.
    /// @param data_ ABI-encoded `TransformData`.
    /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
    function transform(
        bytes32, // callDataHash,
        address payable, // taker,
        bytes calldata data_
    )
        external
        override
        returns (bytes4 success)
    {
        TransformData memory data = abi.decode(data_, (TransformData));
        // Validate data fields.
        if (data.sellToken.isTokenETH() || data.buyToken.isTokenETH()) {
            LibTransformERC20RichErrors.InvalidTransformDataError(
                LibTransformERC20RichErrors.InvalidTransformDataErrorCode.INVALID_TOKENS,
                data_
            ).rrevert();
        }
        if (data.orders.length != data.signatures.length) {
            LibTransformERC20RichErrors.InvalidTransformDataError(
                LibTransformERC20RichErrors.InvalidTransformDataErrorCode.INVALID_ARRAY_LENGTH,
                data_
            ).rrevert();
        }
        if (data.side == Side.Sell && data.fillAmount == MAX_UINT256) {
            // If `sellAmount == -1 then we are selling
            // the entire balance of `sellToken`. This is useful in cases where
            // the exact sell amount is not exactly known in advance, like when
            // unwrapping Chai/cUSDC/cDAI.
            data.fillAmount = data.sellToken.getTokenBalanceOf(address(this));
        }
        // Approve the ERC20 proxy to spend `sellToken`.
        data.sellToken.approveIfBelow(erc20Proxy, data.fillAmount);
        // Fill the orders.
        uint256 singleProtocolFee = exchange.protocolFeeMultiplier().safeMul(tx.gasprice);
        uint256 ethRemaining = address(this).balance;
        uint256 boughtAmount = 0;
        uint256 soldAmount = 0;
        for (uint256 i = 0; i < data.orders.length; ++i) {
            // Check if we've hit our targets.
            if (data.side == Side.Sell) {
                // Market sell check.
                if (soldAmount >= data.fillAmount) {
                    break;
                }
            } else {
                // Market buy check.
                if (boughtAmount >= data.fillAmount) {
                    break;
                }
            }
            // Ensure we have enough ETH to cover the protocol fee.
            if (ethRemaining < singleProtocolFee) {
                LibTransformERC20RichErrors
                    .InsufficientProtocolFeeError(ethRemaining, singleProtocolFee)
                    .rrevert();
            }
            // Fill the order.
            FillOrderResults memory results;
            if (data.side == Side.Sell) {
                // Market sell.
                results = _sellToOrder(
                    data.buyToken,
                    data.sellToken,
                    data.orders[i],
                    data.signatures[i],
                    data.fillAmount.safeSub(soldAmount).min256(
                        data.maxOrderFillAmounts.length > i
                        ? data.maxOrderFillAmounts[i]
                        : MAX_UINT256
                    ),
                    singleProtocolFee
                );
            } else {
                // Market buy.
                results = _buyFromOrder(
                    data.buyToken,
                    data.sellToken,
                    data.orders[i],
                    data.signatures[i],
                    data.fillAmount.safeSub(boughtAmount).min256(
                        data.maxOrderFillAmounts.length > i
                        ? data.maxOrderFillAmounts[i]
                        : MAX_UINT256
                    ),
                    singleProtocolFee
                );
            }
            // Accumulate totals.
            soldAmount = soldAmount.safeAdd(results.takerTokenSoldAmount);
            boughtAmount = boughtAmount.safeAdd(results.makerTokenBoughtAmount);
            ethRemaining = ethRemaining.safeSub(results.protocolFeePaid);
        }
        // Ensure we hit our targets.
        if (data.side == Side.Sell) {
            // Market sell check.
            if (soldAmount < data.fillAmount) {
                LibTransformERC20RichErrors
                    .IncompleteFillSellQuoteError(
                        address(data.sellToken),
                        soldAmount,
                        data.fillAmount
                    ).rrevert();
            }
        } else {
            // Market buy check.
            if (boughtAmount < data.fillAmount) {
                LibTransformERC20RichErrors
                    .IncompleteFillBuyQuoteError(
                        address(data.buyToken),
                        boughtAmount,
                        data.fillAmount
                    ).rrevert();
            }
        }
        return LibERC20Transformer.TRANSFORMER_SUCCESS;
    }
    /// @dev Try to sell up to `sellAmount` from an order.
    /// @param makerToken The maker/buy token.
    /// @param takerToken The taker/sell token.
    /// @param order The order to fill.
    /// @param signature The signature for `order`.
    /// @param sellAmount Amount of taker token to sell.
    /// @param protocolFee The protocol fee needed to fill `order`.
    function _sellToOrder(
        IERC20TokenV06 makerToken,
        IERC20TokenV06 takerToken,
        IExchange.Order memory order,
        bytes memory signature,
        uint256 sellAmount,
        uint256 protocolFee
    )
        private
        returns (FillOrderResults memory results)
    {
        IERC20TokenV06 takerFeeToken =
            _getTokenFromERC20AssetData(order.takerFeeAssetData);
        uint256 takerTokenFillAmount = sellAmount;
        if (order.takerFee != 0) {
            if (takerFeeToken == makerToken) {
                // Taker fee is payable in the maker token, so we need to
                // approve the proxy to spend the maker token.
                // It isn't worth computing the actual taker fee
                // since `approveIfBelow()` will set the allowance to infinite. We
                // just need a reasonable upper bound to avoid unnecessarily re-approving.
                takerFeeToken.approveIfBelow(erc20Proxy, order.takerFee);
            } else if (takerFeeToken == takerToken){
                // Taker fee is payable in the taker token, so we need to
                // reduce the fill amount to cover the fee.
                // takerTokenFillAmount' =
                //   (takerTokenFillAmount * order.takerAssetAmount) /
                //   (order.takerAssetAmount + order.takerFee)
                takerTokenFillAmount = LibMathV06.getPartialAmountCeil(
                    order.takerAssetAmount,
                    order.takerAssetAmount.safeAdd(order.takerFee),
                    sellAmount
                );
            } else {
                //  Only support taker or maker asset denominated taker fees.
                LibTransformERC20RichErrors.InvalidTakerFeeTokenError(
                    address(takerFeeToken)
                ).rrevert();
            }
        }
        // Clamp fill amount to order size.
        takerTokenFillAmount = LibSafeMathV06.min256(
            takerTokenFillAmount,
            order.takerAssetAmount
        );
        // Perform the fill.
        return _fillOrder(
            order,
            signature,
            takerTokenFillAmount,
            protocolFee,
            makerToken,
            takerFeeToken == takerToken
        );
    }
    /// @dev Try to buy up to `buyAmount` from an order.
    /// @param makerToken The maker/buy token.
    /// @param takerToken The taker/sell token.
    /// @param order The order to fill.
    /// @param signature The signature for `order`.
    /// @param buyAmount Amount of maker token to buy.
    /// @param protocolFee The protocol fee needed to fill `order`.
    function _buyFromOrder(
        IERC20TokenV06 makerToken,
        IERC20TokenV06 takerToken,
        IExchange.Order memory order,
        bytes memory signature,
        uint256 buyAmount,
        uint256 protocolFee
    )
        private
        returns (FillOrderResults memory results)
    {
        IERC20TokenV06 takerFeeToken =
            _getTokenFromERC20AssetData(order.takerFeeAssetData);
        // Compute the default taker token fill amount.
        uint256 takerTokenFillAmount = LibMathV06.getPartialAmountCeil(
            buyAmount,
            order.makerAssetAmount,
            order.takerAssetAmount
        );
        if (order.takerFee != 0) {
            if (takerFeeToken == makerToken) {
                // Taker fee is payable in the maker token.
                // Adjust the taker token fill amount to account for maker
                // tokens being lost to the taker fee.
                // takerTokenFillAmount' =
                //  (order.takerAssetAmount * buyAmount) /
                //  (order.makerAssetAmount - order.takerFee)
                takerTokenFillAmount = LibMathV06.getPartialAmountCeil(
                    buyAmount,
                    order.makerAssetAmount.safeSub(order.takerFee),
                    order.takerAssetAmount
                );
                // Approve the proxy to spend the maker token.
                // It isn't worth computing the actual taker fee
                // since `approveIfBelow()` will set the allowance to infinite. We
                // just need a reasonable upper bound to avoid unnecessarily re-approving.
                takerFeeToken.approveIfBelow(erc20Proxy, order.takerFee);
            } else if (takerFeeToken != takerToken) {
                //  Only support taker or maker asset denominated taker fees.
                LibTransformERC20RichErrors.InvalidTakerFeeTokenError(
                    address(takerFeeToken)
                ).rrevert();
            }
        }
        // Clamp to order size.
        takerTokenFillAmount = LibSafeMathV06.min256(
            order.takerAssetAmount,
            takerTokenFillAmount
        );
        // Perform the fill.
        return _fillOrder(
            order,
            signature,
            takerTokenFillAmount,
            protocolFee,
            makerToken,
            takerFeeToken == takerToken
        );
    }
    /// @dev Attempt to fill an order. If the fill reverts, the revert will be
    ///      swallowed and `results` will be zeroed out.
    /// @param order The order to fill.
    /// @param signature The order signature.
    /// @param takerAssetFillAmount How much taker asset to fill.
    /// @param protocolFee The protocol fee needed to fill this order.
    /// @param makerToken The maker token.
    /// @param isTakerFeeInTakerToken Whether the taker fee token is the same as the
    ///        taker token.
    function _fillOrder(
        IExchange.Order memory order,
        bytes memory signature,
        uint256 takerAssetFillAmount,
        uint256 protocolFee,
        IERC20TokenV06 makerToken,
        bool isTakerFeeInTakerToken
    )
        private
        returns (FillOrderResults memory results)
    {
        // Track changes in the maker token balance.
        uint256 initialMakerTokenBalance = makerToken.balanceOf(address(this));
        try
            exchange.fillOrder
                {value: protocolFee}
                (order, takerAssetFillAmount, signature)
            returns (IExchange.FillResults memory fillResults)
        {
            // Update maker quantity based on changes in token balances.
            results.makerTokenBoughtAmount = makerToken.balanceOf(address(this))
                .safeSub(initialMakerTokenBalance);
            // We can trust the other fill result quantities.
            results.protocolFeePaid = fillResults.protocolFeePaid;
            results.takerTokenSoldAmount = fillResults.takerAssetFilledAmount;
            // If the taker fee is payable in the taker asset, include the
            // taker fee in the total amount sold.
            if (isTakerFeeInTakerToken) {
                results.takerTokenSoldAmount =
                    results.takerTokenSoldAmount.safeAdd(fillResults.takerFeePaid);
            }
        } catch (bytes memory) {
            // Swallow failures, leaving all results as zero.
        }
    }
    /// @dev Extract the token from plain ERC20 asset data.
    ///      If the asset-data is empty, a zero token address will be returned.
    /// @param assetData The order asset data.
    function _getTokenFromERC20AssetData(bytes memory assetData)
        private
        pure
        returns (IERC20TokenV06 token)
    {
        if (assetData.length == 0) {
            return IERC20TokenV06(address(0));
        }
        if (assetData.length != 36 ||
            LibBytesV06.readBytes4(assetData, 0) != ERC20_ASSET_PROXY_ID)
        {
            LibTransformERC20RichErrors
                .InvalidERC20AssetDataError(assetData)
                .rrevert();
        }
        return IERC20TokenV06(LibBytesV06.readAddress(assetData, 16));
    }
}
/*
  Copyright 2019 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./LibSafeMathV06.sol";
import "./errors/LibRichErrorsV06.sol";
import "./errors/LibMathRichErrorsV06.sol";
library LibMathV06 {
    using LibSafeMathV06 for uint256;
    /// @dev Calculates partial value given a numerator and denominator rounded down.
    ///      Reverts if rounding error is >= 0.1%
    /// @param numerator Numerator.
    /// @param denominator Denominator.
    /// @param target Value to calculate partial of.
    /// @return partialAmount Partial value of target rounded down.
    function safeGetPartialAmountFloor(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (uint256 partialAmount)
    {
        if (isRoundingErrorFloor(
                numerator,
                denominator,
                target
        )) {
            LibRichErrorsV06.rrevert(LibMathRichErrorsV06.RoundingError(
                numerator,
                denominator,
                target
            ));
        }
        partialAmount = numerator.safeMul(target).safeDiv(denominator);
        return partialAmount;
    }
    /// @dev Calculates partial value given a numerator and denominator rounded down.
    ///      Reverts if rounding error is >= 0.1%
    /// @param numerator Numerator.
    /// @param denominator Denominator.
    /// @param target Value to calculate partial of.
    /// @return partialAmount Partial value of target rounded up.
    function safeGetPartialAmountCeil(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (uint256 partialAmount)
    {
        if (isRoundingErrorCeil(
                numerator,
                denominator,
                target
        )) {
            LibRichErrorsV06.rrevert(LibMathRichErrorsV06.RoundingError(
                numerator,
                denominator,
                target
            ));
        }
        // safeDiv computes `floor(a / b)`. We use the identity (a, b integer):
        //       ceil(a / b) = floor((a + b - 1) / b)
        // To implement `ceil(a / b)` using safeDiv.
        partialAmount = numerator.safeMul(target)
            .safeAdd(denominator.safeSub(1))
            .safeDiv(denominator);
        return partialAmount;
    }
    /// @dev Calculates partial value given a numerator and denominator rounded down.
    /// @param numerator Numerator.
    /// @param denominator Denominator.
    /// @param target Value to calculate partial of.
    /// @return partialAmount Partial value of target rounded down.
    function getPartialAmountFloor(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (uint256 partialAmount)
    {
        partialAmount = numerator.safeMul(target).safeDiv(denominator);
        return partialAmount;
    }
    /// @dev Calculates partial value given a numerator and denominator rounded down.
    /// @param numerator Numerator.
    /// @param denominator Denominator.
    /// @param target Value to calculate partial of.
    /// @return partialAmount Partial value of target rounded up.
    function getPartialAmountCeil(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (uint256 partialAmount)
    {
        // safeDiv computes `floor(a / b)`. We use the identity (a, b integer):
        //       ceil(a / b) = floor((a + b - 1) / b)
        // To implement `ceil(a / b)` using safeDiv.
        partialAmount = numerator.safeMul(target)
            .safeAdd(denominator.safeSub(1))
            .safeDiv(denominator);
        return partialAmount;
    }
    /// @dev Checks if rounding error >= 0.1% when rounding down.
    /// @param numerator Numerator.
    /// @param denominator Denominator.
    /// @param target Value to multiply with numerator/denominator.
    /// @return isError Rounding error is present.
    function isRoundingErrorFloor(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (bool isError)
    {
        if (denominator == 0) {
            LibRichErrorsV06.rrevert(LibMathRichErrorsV06.DivisionByZeroError());
        }
        // The absolute rounding error is the difference between the rounded
        // value and the ideal value. The relative rounding error is the
        // absolute rounding error divided by the absolute value of the
        // ideal value. This is undefined when the ideal value is zero.
        //
        // The ideal value is `numerator * target / denominator`.
        // Let's call `numerator * target % denominator` the remainder.
        // The absolute error is `remainder / denominator`.
        //
        // When the ideal value is zero, we require the absolute error to
        // be zero. Fortunately, this is always the case. The ideal value is
        // zero iff `numerator == 0` and/or `target == 0`. In this case the
        // remainder and absolute error are also zero.
        if (target == 0 || numerator == 0) {
            return false;
        }
        // Otherwise, we want the relative rounding error to be strictly
        // less than 0.1%.
        // The relative error is `remainder / (numerator * target)`.
        // We want the relative error less than 1 / 1000:
        //        remainder / (numerator * denominator)  <  1 / 1000
        // or equivalently:
        //        1000 * remainder  <  numerator * target
        // so we have a rounding error iff:
        //        1000 * remainder  >=  numerator * target
        uint256 remainder = mulmod(
            target,
            numerator,
            denominator
        );
        isError = remainder.safeMul(1000) >= numerator.safeMul(target);
        return isError;
    }
    /// @dev Checks if rounding error >= 0.1% when rounding up.
    /// @param numerator Numerator.
    /// @param denominator Denominator.
    /// @param target Value to multiply with numerator/denominator.
    /// @return isError Rounding error is present.
    function isRoundingErrorCeil(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (bool isError)
    {
        if (denominator == 0) {
            LibRichErrorsV06.rrevert(LibMathRichErrorsV06.DivisionByZeroError());
        }
        // See the comments in `isRoundingError`.
        if (target == 0 || numerator == 0) {
            // When either is zero, the ideal value and rounded value are zero
            // and there is no rounding error. (Although the relative error
            // is undefined.)
            return false;
        }
        // Compute remainder as before
        uint256 remainder = mulmod(
            target,
            numerator,
            denominator
        );
        remainder = denominator.safeSub(remainder) % denominator;
        isError = remainder.safeMul(1000) >= numerator.safeMul(target);
        return isError;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibMathRichErrorsV06 {
    // bytes4(keccak256("DivisionByZeroError()"))
    bytes internal constant DIVISION_BY_ZERO_ERROR =
        hex"a791837c";
    // bytes4(keccak256("RoundingError(uint256,uint256,uint256)"))
    bytes4 internal constant ROUNDING_ERROR_SELECTOR =
        0x339f3de2;
    // solhint-disable func-name-mixedcase
    function DivisionByZeroError()
        internal
        pure
        returns (bytes memory)
    {
        return DIVISION_BY_ZERO_ERROR;
    }
    function RoundingError(
        uint256 numerator,
        uint256 denominator,
        uint256 target
    )
        internal
        pure
        returns (bytes memory)
    {
        return abi.encodeWithSelector(
            ROUNDING_ERROR_SELECTOR,
            numerator,
            denominator,
            target
        );
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Interface to the V3 Exchange.
interface IExchange {
    /// @dev V3 Order structure.
    struct Order {
        // Address that created the order.
        address makerAddress;
        // Address that is allowed to fill the order.
        // If set to 0, any address is allowed to fill the order.
        address takerAddress;
        // Address that will recieve fees when order is filled.
        address feeRecipientAddress;
        // Address that is allowed to call Exchange contract methods that affect this order.
        // If set to 0, any address is allowed to call these methods.
        address senderAddress;
        // Amount of makerAsset being offered by maker. Must be greater than 0.
        uint256 makerAssetAmount;
        // Amount of takerAsset being bid on by maker. Must be greater than 0.
        uint256 takerAssetAmount;
        // Fee paid to feeRecipient by maker when order is filled.
        uint256 makerFee;
        // Fee paid to feeRecipient by taker when order is filled.
        uint256 takerFee;
        // Timestamp in seconds at which order expires.
        uint256 expirationTimeSeconds;
        // Arbitrary number to facilitate uniqueness of the order's hash.
        uint256 salt;
        // Encoded data that can be decoded by a specified proxy contract when transferring makerAsset.
        // The leading bytes4 references the id of the asset proxy.
        bytes makerAssetData;
        // Encoded data that can be decoded by a specified proxy contract when transferring takerAsset.
        // The leading bytes4 references the id of the asset proxy.
        bytes takerAssetData;
        // Encoded data that can be decoded by a specified proxy contract when transferring makerFeeAsset.
        // The leading bytes4 references the id of the asset proxy.
        bytes makerFeeAssetData;
        // Encoded data that can be decoded by a specified proxy contract when transferring takerFeeAsset.
        // The leading bytes4 references the id of the asset proxy.
        bytes takerFeeAssetData;
    }
    /// @dev V3 `fillOrder()` results.`
    struct FillResults {
        // Total amount of makerAsset(s) filled.
        uint256 makerAssetFilledAmount;
        // Total amount of takerAsset(s) filled.
        uint256 takerAssetFilledAmount;
        // Total amount of fees paid by maker(s) to feeRecipient(s).
        uint256 makerFeePaid;
        // Total amount of fees paid by taker to feeRecipients(s).
        uint256 takerFeePaid;
        // Total amount of fees paid by taker to the staking contract.
        uint256 protocolFeePaid;
    }
    /// @dev Fills the input order.
    /// @param order Order struct containing order specifications.
    /// @param takerAssetFillAmount Desired amount of takerAsset to sell.
    /// @param signature Proof that order has been created by maker.
    /// @return fillResults Amounts filled and fees paid by maker and taker.
    function fillOrder(
        Order calldata order,
        uint256 takerAssetFillAmount,
        bytes calldata signature
    )
        external
        payable
        returns (FillResults memory fillResults);
    /// @dev Returns the protocolFeeMultiplier
    /// @return multiplier The multiplier for protocol fees.
    function protocolFeeMultiplier()
        external
        view
        returns (uint256 multiplier);
    /// @dev Gets an asset proxy.
    /// @param assetProxyId Id of the asset proxy.
    /// @return proxyAddress The asset proxy registered to assetProxyId.
    ///         Returns 0x0 if no proxy is registered.
    function getAssetProxy(bytes4 assetProxyId)
        external
        view
        returns (address proxyAddress);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/LibERC20TokenV06.sol";
import "../errors/LibTransformERC20RichErrors.sol";
import "./Transformer.sol";
import "./LibERC20Transformer.sol";
/// @dev A transformer that transfers tokens to the taker.
contract PayTakerTransformer is
    Transformer
{
    // solhint-disable no-empty-blocks
    using LibRichErrorsV06 for bytes;
    using LibSafeMathV06 for uint256;
    using LibERC20Transformer for IERC20TokenV06;
    /// @dev Transform data to ABI-encode and pass into `transform()`.
    struct TransformData {
        // The tokens to transfer to the taker.
        IERC20TokenV06[] tokens;
        // Amount of each token in `tokens` to transfer to the taker.
        // `uint(-1)` will transfer the entire balance.
        uint256[] amounts;
    }
    /// @dev Maximum uint256 value.
    uint256 private constant MAX_UINT256 = uint256(-1);
    /// @dev Create this contract.
    constructor()
        public
        Transformer()
    {}
    /// @dev Forwards tokens to the taker.
    /// @param taker The taker address (caller of `TransformERC20.transformERC20()`).
    /// @param data_ ABI-encoded `TransformData`, indicating which tokens to transfer.
    /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
    function transform(
        bytes32, // callDataHash,
        address payable taker,
        bytes calldata data_
    )
        external
        override
        returns (bytes4 success)
    {
        TransformData memory data = abi.decode(data_, (TransformData));
        // Transfer tokens directly to the taker.
        for (uint256 i = 0; i < data.tokens.length; ++i) {
            // The `amounts` array can be shorter than the `tokens` array.
            // Missing elements are treated as `uint256(-1)`.
            uint256 amount = data.amounts.length > i ? data.amounts[i] : uint256(-1);
            if (amount == MAX_UINT256) {
                amount = data.tokens[i].getTokenBalanceOf(address(this));
            }
            if (amount != 0) {
                data.tokens[i].transformerTransfer(taker, amount);
            }
        }
        return LibERC20Transformer.TRANSFORMER_SUCCESS;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/IEtherTokenV06.sol";
import "../errors/LibTransformERC20RichErrors.sol";
import "./Transformer.sol";
import "./LibERC20Transformer.sol";
/// @dev A transformer that wraps or unwraps WETH.
contract WethTransformer is
    Transformer
{
    using LibRichErrorsV06 for bytes;
    using LibSafeMathV06 for uint256;
    using LibERC20Transformer for IERC20TokenV06;
    /// @dev Transform data to ABI-encode and pass into `transform()`.
    struct TransformData {
        // The token to wrap/unwrap. Must be either ETH or WETH.
        IERC20TokenV06 token;
        // Amount of `token` to wrap or unwrap.
        // `uint(-1)` will unwrap the entire balance.
        uint256 amount;
    }
    /// @dev The WETH contract address.
    IEtherTokenV06 public immutable weth;
    /// @dev Maximum uint256 value.
    uint256 private constant MAX_UINT256 = uint256(-1);
    /// @dev Construct the transformer and store the WETH address in an immutable.
    /// @param weth_ The weth token.
    constructor(IEtherTokenV06 weth_)
        public
        Transformer()
    {
        weth = weth_;
    }
    /// @dev Wraps and unwraps WETH.
    /// @param data_ ABI-encoded `TransformData`, indicating which token to wrap/umwrap.
    /// @return success The success bytes (`LibERC20Transformer.TRANSFORMER_SUCCESS`).
    function transform(
        bytes32, // callDataHash,
        address payable, // taker,
        bytes calldata data_
    )
        external
        override
        returns (bytes4 success)
    {
        TransformData memory data = abi.decode(data_, (TransformData));
        if (!data.token.isTokenETH() && data.token != weth) {
            LibTransformERC20RichErrors.InvalidTransformDataError(
                LibTransformERC20RichErrors.InvalidTransformDataErrorCode.INVALID_TOKENS,
                data_
            ).rrevert();
        }
        uint256 amount = data.amount;
        if (amount == MAX_UINT256) {
            amount = data.token.getTokenBalanceOf(address(this));
        }
        if (amount != 0) {
            if (data.token.isTokenETH()) {
                // Wrap ETH.
                weth.deposit{value: amount}();
            } else {
                // Unwrap WETH.
                weth.withdraw(amount);
            }
        }
        return LibERC20Transformer.TRANSFORMER_SUCCESS;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./IERC20TokenV06.sol";
interface IEtherTokenV06 is
    IERC20TokenV06
{
    /// @dev Wrap ether.
    function deposit() external payable;
    /// @dev Unwrap ether.
    function withdraw(uint256 amount) external;
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
interface ITestSimpleFunctionRegistryFeature {
    function testFn() external view returns (uint256 id);
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
contract TestCallTarget {
    event CallTargetCalled(
        address context,
        address sender,
        bytes data,
        uint256 value
    );
    bytes4 private constant MAGIC_BYTES = 0x12345678;
    bytes private constant REVERTING_DATA = hex"1337";
    fallback() external payable {
        if (keccak256(msg.data) == keccak256(REVERTING_DATA)) {
            revert("TestCallTarget/REVERT");
        }
        emit CallTargetCalled(
            address(this),
            msg.sender,
            msg.data,
            msg.value
        );
        bytes4 rval = MAGIC_BYTES;
        assembly {
            mstore(0, rval)
            return(0, 32)
        }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
contract TestDelegateCaller {
    function executeDelegateCall(
        address target,
        bytes calldata callData
    )
        external
    {
        (bool success, bytes memory resultData) = target.delegatecall(callData);
        if (!success) {
            assembly { revert(add(resultData, 32), mload(resultData)) }
        }
        assembly { return(add(resultData, 32), mload(resultData)) }
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibMathV06.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
import "../src/vendor/v3/IExchange.sol";
import "./TestMintableERC20Token.sol";
contract TestFillQuoteTransformerExchange {
    struct FillBehavior {
        // How much of the order is filled, in taker asset amount.
        uint256 filledTakerAssetAmount;
        // Scaling for maker assets minted, in 1e18.
        uint256 makerAssetMintRatio;
    }
    uint256 private constant PROTOCOL_FEE_MULTIPLIER = 1337;
    using LibSafeMathV06 for uint256;
    function fillOrder(
        IExchange.Order calldata order,
        uint256 takerAssetFillAmount,
        bytes calldata signature
    )
        external
        payable
        returns (IExchange.FillResults memory fillResults)
    {
        require(
            signature.length != 0,
            "TestFillQuoteTransformerExchange/INVALID_SIGNATURE"
        );
        // The signature is the ABI-encoded FillBehavior data.
        FillBehavior memory behavior = abi.decode(signature, (FillBehavior));
        uint256 protocolFee = PROTOCOL_FEE_MULTIPLIER * tx.gasprice;
        require(
            msg.value == protocolFee,
            "TestFillQuoteTransformerExchange/INSUFFICIENT_PROTOCOL_FEE"
        );
        // Return excess protocol fee.
        msg.sender.transfer(msg.value - protocolFee);
        // Take taker tokens.
        TestMintableERC20Token takerToken = _getTokenFromAssetData(order.takerAssetData);
        takerAssetFillAmount = LibSafeMathV06.min256(
            order.takerAssetAmount.safeSub(behavior.filledTakerAssetAmount),
            takerAssetFillAmount
        );
        require(
            takerToken.getSpendableAmount(msg.sender, address(this)) >= takerAssetFillAmount,
            "TestFillQuoteTransformerExchange/INSUFFICIENT_TAKER_FUNDS"
        );
        takerToken.transferFrom(msg.sender, order.makerAddress, takerAssetFillAmount);
        // Mint maker tokens.
        uint256 makerAssetFilledAmount = LibMathV06.getPartialAmountFloor(
            takerAssetFillAmount,
            order.takerAssetAmount,
            order.makerAssetAmount
        );
        TestMintableERC20Token makerToken = _getTokenFromAssetData(order.makerAssetData);
        makerToken.mint(
            msg.sender,
            LibMathV06.getPartialAmountFloor(
                behavior.makerAssetMintRatio,
                1e18,
                makerAssetFilledAmount
            )
        );
        // Take taker fee.
        TestMintableERC20Token takerFeeToken = _getTokenFromAssetData(order.takerFeeAssetData);
        uint256 takerFee = LibMathV06.getPartialAmountFloor(
            takerAssetFillAmount,
            order.takerAssetAmount,
            order.takerFee
        );
        require(
            takerFeeToken.getSpendableAmount(msg.sender, address(this)) >= takerFee,
            "TestFillQuoteTransformerExchange/INSUFFICIENT_TAKER_FEE_FUNDS"
        );
        takerFeeToken.transferFrom(msg.sender, order.feeRecipientAddress, takerFee);
        fillResults.makerAssetFilledAmount = makerAssetFilledAmount;
        fillResults.takerAssetFilledAmount = takerAssetFillAmount;
        fillResults.makerFeePaid = uint256(-1);
        fillResults.takerFeePaid = takerFee;
        fillResults.protocolFeePaid = protocolFee;
    }
    function encodeBehaviorData(FillBehavior calldata behavior)
        external
        pure
        returns (bytes memory encoded)
    {
        return abi.encode(behavior);
    }
    function protocolFeeMultiplier()
        external
        pure
        returns (uint256)
    {
        return PROTOCOL_FEE_MULTIPLIER;
    }
    function getAssetProxy(bytes4)
        external
        view
        returns (address)
    {
        return address(this);
    }
    function _getTokenFromAssetData(bytes memory assetData)
        private
        pure
        returns (TestMintableERC20Token token)
    {
        return TestMintableERC20Token(LibBytesV06.readAddress(assetData, 16));
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
contract TestMintableERC20Token {
    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) public allowance;
    function transfer(address to, uint256 amount)
        external
        virtual
        returns (bool)
    {
        return transferFrom(msg.sender, to, amount);
    }
    function approve(address spender, uint256 amount)
        external
        virtual
        returns (bool)
    {
        allowance[msg.sender][spender] = amount;
        return true;
    }
    function mint(address owner, uint256 amount)
        external
        virtual
    {
        balanceOf[owner] += amount;
    }
    function burn(address owner, uint256 amount)
        external
        virtual
    {
        require(balanceOf[owner] >= amount, "TestMintableERC20Token/INSUFFICIENT_FUNDS");
        balanceOf[owner] -= amount;
    }
    function transferFrom(address from, address to, uint256 amount)
        public
        virtual
        returns (bool)
    {
        if (from != msg.sender) {
            require(
                allowance[from][msg.sender] >= amount,
                "TestMintableERC20Token/INSUFFICIENT_ALLOWANCE"
            );
            allowance[from][msg.sender] -= amount;
        }
        require(balanceOf[from] >= amount, "TestMintableERC20Token/INSUFFICIENT_FUNDS");
        balanceOf[from] -= amount;
        balanceOf[to] += amount;
        return true;
    }
    function getSpendableAmount(address owner, address spender)
        external
        view
        returns (uint256)
    {
        return balanceOf[owner] < allowance[owner][spender]
            ? balanceOf[owner]
            : allowance[owner][spender];
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/transformers/IERC20Transformer.sol";
import "./TestMintableERC20Token.sol";
import "./TestTransformerHost.sol";
contract TestFillQuoteTransformerHost is
    TestTransformerHost
{
    function executeTransform(
        IERC20Transformer transformer,
        TestMintableERC20Token inputToken,
        uint256 inputTokenAmount,
        bytes calldata data
    )
        external
        payable
    {
        if (inputTokenAmount != 0) {
            inputToken.mint(address(this), inputTokenAmount);
        }
        // Have to make this call externally because transformers aren't payable.
        this.rawExecuteTransform(transformer, bytes32(0), msg.sender, data);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "../src/transformers/IERC20Transformer.sol";
import "../src/transformers/LibERC20Transformer.sol";
contract TestTransformerHost {
    using LibERC20Transformer for IERC20TokenV06;
    using LibRichErrorsV06 for bytes;
    function rawExecuteTransform(
        IERC20Transformer transformer,
        bytes32 callDataHash,
        address taker,
        bytes calldata data
    )
        external
    {
        (bool _success, bytes memory resultData) =
            address(transformer).delegatecall(abi.encodeWithSelector(
                transformer.transform.selector,
                callDataHash,
                taker,
                data
            ));
        if (!_success) {
            resultData.rrevert();
        }
        require(
            abi.decode(resultData, (bytes4)) == LibERC20Transformer.TRANSFORMER_SUCCESS,
            "TestTransformerHost/INVALID_TRANSFORMER_RESULT"
        );
    }
    // solhint-disable
    receive() external payable {}
    // solhint-enable
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/ZeroEx.sol";
import "../src/features/IBootstrap.sol";
import "../src/migrations/FullMigration.sol";
contract TestFullMigration is
    FullMigration
{
    address public dieRecipient;
    // solhint-disable-next-line no-empty-blocks
    constructor(address payable deployer) public FullMigration(deployer) {}
    function die(address payable ethRecipient) external override {
        dieRecipient = ethRecipient;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/ZeroEx.sol";
import "../src/features/IBootstrap.sol";
import "../src/migrations/InitialMigration.sol";
contract TestInitialMigration is
    InitialMigration
{
    address public bootstrapFeature;
    address public dieRecipient;
    // solhint-disable-next-line no-empty-blocks
    constructor(address deployer) public InitialMigration(deployer) {}
    function callBootstrap(ZeroEx zeroEx) external {
        IBootstrap(address(zeroEx)).bootstrap(address(this), new bytes(0));
    }
    function bootstrap(address owner, BootstrapFeatures memory features)
        public
        override
        returns (bytes4 success)
    {
        success = InitialMigration.bootstrap(owner, features);
        // Snoop the bootstrap feature contract.
        bootstrapFeature = ZeroEx(address(uint160(address(this))))
            .getFunctionImplementation(IBootstrap.bootstrap.selector);
    }
    function die(address payable ethRecipient) public override {
        dieRecipient = ethRecipient;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/migrations/LibMigrate.sol";
import "../src/features/IOwnable.sol";
contract TestMigrator {
    event TestMigrateCalled(
        bytes callData,
        address owner
    );
    function succeedingMigrate() external returns (bytes4 success) {
        emit TestMigrateCalled(
            msg.data,
            IOwnable(address(this)).owner()
        );
        return LibMigrate.MIGRATE_SUCCESS;
    }
    function failingMigrate() external returns (bytes4 success) {
        emit TestMigrateCalled(
            msg.data,
            IOwnable(address(this)).owner()
        );
        return 0xdeadbeef;
    }
    function revertingMigrate() external pure {
        revert("OOPSIE");
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/contracts/src/v06/IERC20TokenV06.sol";
import "../src/transformers/IERC20Transformer.sol";
import "../src/transformers/LibERC20Transformer.sol";
import "./TestMintableERC20Token.sol";
contract TestMintTokenERC20Transformer is
    IERC20Transformer
{
    struct TransformData {
        IERC20TokenV06 inputToken;
        TestMintableERC20Token outputToken;
        uint256 burnAmount;
        uint256 mintAmount;
        uint256 feeAmount;
    }
    event MintTransform(
        address context,
        address caller,
        bytes32 callDataHash,
        address taker,
        bytes data,
        uint256 inputTokenBalance,
        uint256 ethBalance
    );
    function transform(
        bytes32 callDataHash,
        address payable taker,
        bytes calldata data_
    )
        external
        override
        returns (bytes4 success)
    {
        TransformData memory data = abi.decode(data_, (TransformData));
        emit MintTransform(
            address(this),
            msg.sender,
            callDataHash,
            taker,
            data_,
            data.inputToken.balanceOf(address(this)),
            address(this).balance
        );
        // "Burn" input tokens.
        data.inputToken.transfer(address(0), data.burnAmount);
        // Mint output tokens.
        if (LibERC20Transformer.isTokenETH(IERC20TokenV06(address(data.outputToken)))) {
            taker.transfer(data.mintAmount);
        } else {
            data.outputToken.mint(
                taker,
                data.mintAmount
            );
            // Burn fees from output.
            data.outputToken.burn(taker, data.feeAmount);
        }
        return LibERC20Transformer.TRANSFORMER_SUCCESS;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/fixins/FixinCommon.sol";
contract TestSimpleFunctionRegistryFeatureImpl1 is
    FixinCommon
{
    function testFn()
        external
        pure
        returns (uint256 id)
    {
        return 1337;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/fixins/FixinCommon.sol";
contract TestSimpleFunctionRegistryFeatureImpl2 is
    FixinCommon
{
    function testFn()
        external
        pure
        returns (uint256 id)
    {
        return 1338;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/features/TokenSpender.sol";
contract TestTokenSpender is
    TokenSpender
{
    modifier onlySelf() override {
        _;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./TestMintableERC20Token.sol";
contract TestTokenSpenderERC20Token is
    TestMintableERC20Token
{
    event TransferFromCalled(
        address sender,
        address from,
        address to,
        uint256 amount
    );
    // `transferFrom()` behavior depends on the value of `amount`.
    uint256 constant private EMPTY_RETURN_AMOUNT = 1337;
    uint256 constant private FALSE_RETURN_AMOUNT = 1338;
    uint256 constant private REVERT_RETURN_AMOUNT = 1339;
    function transferFrom(address from, address to, uint256 amount)
        public
        override
        returns (bool)
    {
        emit TransferFromCalled(msg.sender, from, to, amount);
        if (amount == EMPTY_RETURN_AMOUNT) {
            assembly { return(0, 0) }
        }
        if (amount == FALSE_RETURN_AMOUNT) {
            return false;
        }
        if (amount == REVERT_RETURN_AMOUNT) {
            revert("TestTokenSpenderERC20Token/Revert");
        }
        return true;
    }
    function setBalanceAndAllowanceOf(
        address owner,
        uint256 balance,
        address spender,
        uint256 allowance_
    )
        external
    {
        balanceOf[owner] = balance;
        allowance[owner][spender] = allowance_;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/features/TransformERC20.sol";
contract TestTransformERC20 is
    TransformERC20
{
    // solhint-disable no-empty-blocks
    constructor()
        TransformERC20()
        public
    {}
    modifier onlySelf() override {
        _;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/transformers/Transformer.sol";
import "../src/transformers/LibERC20Transformer.sol";
contract TestTransformerBase is
    Transformer
{
    function transform(
        bytes32,
        address payable,
        bytes calldata
    )
        external
        override
        returns (bytes4 success)
    {
        return LibERC20Transformer.TRANSFORMER_SUCCESS;
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/transformers/LibERC20Transformer.sol";
contract TestTransformerDeployerTransformer {
    address payable public immutable deployer;
    constructor() public payable {
        deployer = msg.sender;
    }
    modifier onlyDeployer() {
        require(msg.sender == deployer, "TestTransformerDeployerTransformer/ONLY_DEPLOYER");
        _;
    }
    function die()
        external
        onlyDeployer
    {
        selfdestruct(deployer);
    }
    function isDeployedByDeployer(uint32 nonce)
        external
        view
        returns (bool)
    {
        return LibERC20Transformer.getDeployedAddress(deployer, nonce) == address(this);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "./TestMintableERC20Token.sol";
contract TestWeth is
    TestMintableERC20Token
{
    function deposit()
        external
        payable
    {
        this.mint(msg.sender, msg.value);
    }
    function withdraw(uint256 amount)
        external
    {
        require(balanceOf[msg.sender] >= amount, "TestWeth/INSUFFICIENT_FUNDS");
        balanceOf[msg.sender] -= amount;
        msg.sender.transfer(amount);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/transformers/IERC20Transformer.sol";
import "./TestMintableERC20Token.sol";
import "./TestTransformerHost.sol";
import "./TestWeth.sol";
contract TestWethTransformerHost is
    TestTransformerHost
{
    // solhint-disable
    TestWeth private immutable _weth;
    // solhint-enable
    constructor(TestWeth weth) public {
        _weth = weth;
    }
    function executeTransform(
        uint256 wethAmount,
        IERC20Transformer transformer,
        bytes calldata data
    )
        external
        payable
    {
        if (wethAmount != 0) {
            _weth.deposit{value: wethAmount}();
        }
        // Have to make this call externally because transformers aren't payable.
        this.rawExecuteTransform(transformer, bytes32(0), msg.sender, data);
    }
}
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "../src/fixins/FixinCommon.sol";
import "../src/ZeroEx.sol";
contract TestZeroExFeature is
    FixinCommon
{
    event PayableFnCalled(uint256 value);
    event NotPayableFnCalled();
    function payableFn()
        external
        payable
    {
        emit PayableFnCalled(msg.value);
    }
    function notPayableFn()
        external
    {
        emit NotPayableFnCalled();
    }
    // solhint-disable no-empty-blocks
    function unimplmentedFn()
        external
    {}
    function internalFn()
        external
        onlySelf
    {}
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
import './interfaces/IUniswapV3Pool.sol';
import './NoDelegateCall.sol';
import './libraries/LowGasSafeMath.sol';
import './libraries/SafeCast.sol';
import './libraries/Tick.sol';
import './libraries/TickBitmap.sol';
import './libraries/Position.sol';
import './libraries/Oracle.sol';
import './libraries/FullMath.sol';
import './libraries/FixedPoint128.sol';
import './libraries/TransferHelper.sol';
import './libraries/TickMath.sol';
import './libraries/LiquidityMath.sol';
import './libraries/SqrtPriceMath.sol';
import './libraries/SwapMath.sol';
import './interfaces/IUniswapV3PoolDeployer.sol';
import './interfaces/IUniswapV3Factory.sol';
import './interfaces/IERC20Minimal.sol';
import './interfaces/callback/IUniswapV3MintCallback.sol';
import './interfaces/callback/IUniswapV3SwapCallback.sol';
import './interfaces/callback/IUniswapV3FlashCallback.sol';
contract UniswapV3Pool is IUniswapV3Pool, NoDelegateCall {
    using LowGasSafeMath for uint256;
    using LowGasSafeMath for int256;
    using SafeCast for uint256;
    using SafeCast for int256;
    using Tick for mapping(int24 => Tick.Info);
    using TickBitmap for mapping(int16 => uint256);
    using Position for mapping(bytes32 => Position.Info);
    using Position for Position.Info;
    using Oracle for Oracle.Observation[65535];
    /// @inheritdoc IUniswapV3PoolImmutables
    address public immutable override factory;
    /// @inheritdoc IUniswapV3PoolImmutables
    address public immutable override token0;
    /// @inheritdoc IUniswapV3PoolImmutables
    address public immutable override token1;
    /// @inheritdoc IUniswapV3PoolImmutables
    uint24 public immutable override fee;
    /// @inheritdoc IUniswapV3PoolImmutables
    int24 public immutable override tickSpacing;
    /// @inheritdoc IUniswapV3PoolImmutables
    uint128 public immutable override maxLiquidityPerTick;
    struct Slot0 {
        // the current price
        uint160 sqrtPriceX96;
        // the current tick
        int24 tick;
        // the most-recently updated index of the observations array
        uint16 observationIndex;
        // the current maximum number of observations that are being stored
        uint16 observationCardinality;
        // the next maximum number of observations to store, triggered in observations.write
        uint16 observationCardinalityNext;
        // the current protocol fee as a percentage of the swap fee taken on withdrawal
        // represented as an integer denominator (1/x)%
        uint8 feeProtocol;
        // whether the pool is locked
        bool unlocked;
    }
    /// @inheritdoc IUniswapV3PoolState
    Slot0 public override slot0;
    /// @inheritdoc IUniswapV3PoolState
    uint256 public override feeGrowthGlobal0X128;
    /// @inheritdoc IUniswapV3PoolState
    uint256 public override feeGrowthGlobal1X128;
    // accumulated protocol fees in token0/token1 units
    struct ProtocolFees {
        uint128 token0;
        uint128 token1;
    }
    /// @inheritdoc IUniswapV3PoolState
    ProtocolFees public override protocolFees;
    /// @inheritdoc IUniswapV3PoolState
    uint128 public override liquidity;
    /// @inheritdoc IUniswapV3PoolState
    mapping(int24 => Tick.Info) public override ticks;
    /// @inheritdoc IUniswapV3PoolState
    mapping(int16 => uint256) public override tickBitmap;
    /// @inheritdoc IUniswapV3PoolState
    mapping(bytes32 => Position.Info) public override positions;
    /// @inheritdoc IUniswapV3PoolState
    Oracle.Observation[65535] public override observations;
    /// @dev Mutually exclusive reentrancy protection into the pool to/from a method. This method also prevents entrance
    /// to a function before the pool is initialized. The reentrancy guard is required throughout the contract because
    /// we use balance checks to determine the payment status of interactions such as mint, swap and flash.
    modifier lock() {
        require(slot0.unlocked, 'LOK');
        slot0.unlocked = false;
        _;
        slot0.unlocked = true;
    }
    /// @dev Prevents calling a function from anyone except the address returned by IUniswapV3Factory#owner()
    modifier onlyFactoryOwner() {
        require(msg.sender == IUniswapV3Factory(factory).owner());
        _;
    }
    constructor() {
        int24 _tickSpacing;
        (factory, token0, token1, fee, _tickSpacing) = IUniswapV3PoolDeployer(msg.sender).parameters();
        tickSpacing = _tickSpacing;
        maxLiquidityPerTick = Tick.tickSpacingToMaxLiquidityPerTick(_tickSpacing);
    }
    /// @dev Common checks for valid tick inputs.
    function checkTicks(int24 tickLower, int24 tickUpper) private pure {
        require(tickLower < tickUpper, 'TLU');
        require(tickLower >= TickMath.MIN_TICK, 'TLM');
        require(tickUpper <= TickMath.MAX_TICK, 'TUM');
    }
    /// @dev Returns the block timestamp truncated to 32 bits, i.e. mod 2**32. This method is overridden in tests.
    function _blockTimestamp() internal view virtual returns (uint32) {
        return uint32(block.timestamp); // truncation is desired
    }
    /// @dev Get the pool's balance of token0
    /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
    /// check
    function balance0() private view returns (uint256) {
        (bool success, bytes memory data) =
            token0.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
        require(success && data.length >= 32);
        return abi.decode(data, (uint256));
    }
    /// @dev Get the pool's balance of token1
    /// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
    /// check
    function balance1() private view returns (uint256) {
        (bool success, bytes memory data) =
            token1.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
        require(success && data.length >= 32);
        return abi.decode(data, (uint256));
    }
    /// @inheritdoc IUniswapV3PoolDerivedState
    function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
        external
        view
        override
        noDelegateCall
        returns (
            int56 tickCumulativeInside,
            uint160 secondsPerLiquidityInsideX128,
            uint32 secondsInside
        )
    {
        checkTicks(tickLower, tickUpper);
        int56 tickCumulativeLower;
        int56 tickCumulativeUpper;
        uint160 secondsPerLiquidityOutsideLowerX128;
        uint160 secondsPerLiquidityOutsideUpperX128;
        uint32 secondsOutsideLower;
        uint32 secondsOutsideUpper;
        {
            Tick.Info storage lower = ticks[tickLower];
            Tick.Info storage upper = ticks[tickUpper];
            bool initializedLower;
            (tickCumulativeLower, secondsPerLiquidityOutsideLowerX128, secondsOutsideLower, initializedLower) = (
                lower.tickCumulativeOutside,
                lower.secondsPerLiquidityOutsideX128,
                lower.secondsOutside,
                lower.initialized
            );
            require(initializedLower);
            bool initializedUpper;
            (tickCumulativeUpper, secondsPerLiquidityOutsideUpperX128, secondsOutsideUpper, initializedUpper) = (
                upper.tickCumulativeOutside,
                upper.secondsPerLiquidityOutsideX128,
                upper.secondsOutside,
                upper.initialized
            );
            require(initializedUpper);
        }
        Slot0 memory _slot0 = slot0;
        if (_slot0.tick < tickLower) {
            return (
                tickCumulativeLower - tickCumulativeUpper,
                secondsPerLiquidityOutsideLowerX128 - secondsPerLiquidityOutsideUpperX128,
                secondsOutsideLower - secondsOutsideUpper
            );
        } else if (_slot0.tick < tickUpper) {
            uint32 time = _blockTimestamp();
            (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) =
                observations.observeSingle(
                    time,
                    0,
                    _slot0.tick,
                    _slot0.observationIndex,
                    liquidity,
                    _slot0.observationCardinality
                );
            return (
                tickCumulative - tickCumulativeLower - tickCumulativeUpper,
                secondsPerLiquidityCumulativeX128 -
                    secondsPerLiquidityOutsideLowerX128 -
                    secondsPerLiquidityOutsideUpperX128,
                time - secondsOutsideLower - secondsOutsideUpper
            );
        } else {
            return (
                tickCumulativeUpper - tickCumulativeLower,
                secondsPerLiquidityOutsideUpperX128 - secondsPerLiquidityOutsideLowerX128,
                secondsOutsideUpper - secondsOutsideLower
            );
        }
    }
    /// @inheritdoc IUniswapV3PoolDerivedState
    function observe(uint32[] calldata secondsAgos)
        external
        view
        override
        noDelegateCall
        returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s)
    {
        return
            observations.observe(
                _blockTimestamp(),
                secondsAgos,
                slot0.tick,
                slot0.observationIndex,
                liquidity,
                slot0.observationCardinality
            );
    }
    /// @inheritdoc IUniswapV3PoolActions
    function increaseObservationCardinalityNext(uint16 observationCardinalityNext)
        external
        override
        lock
        noDelegateCall
    {
        uint16 observationCardinalityNextOld = slot0.observationCardinalityNext; // for the event
        uint16 observationCardinalityNextNew =
            observations.grow(observationCardinalityNextOld, observationCardinalityNext);
        slot0.observationCardinalityNext = observationCardinalityNextNew;
        if (observationCardinalityNextOld != observationCardinalityNextNew)
            emit IncreaseObservationCardinalityNext(observationCardinalityNextOld, observationCardinalityNextNew);
    }
    /// @inheritdoc IUniswapV3PoolActions
    /// @dev not locked because it initializes unlocked
    function initialize(uint160 sqrtPriceX96) external override {
        require(slot0.sqrtPriceX96 == 0, 'AI');
        int24 tick = TickMath.getTickAtSqrtRatio(sqrtPriceX96);
        (uint16 cardinality, uint16 cardinalityNext) = observations.initialize(_blockTimestamp());
        slot0 = Slot0({
            sqrtPriceX96: sqrtPriceX96,
            tick: tick,
            observationIndex: 0,
            observationCardinality: cardinality,
            observationCardinalityNext: cardinalityNext,
            feeProtocol: 0,
            unlocked: true
        });
        emit Initialize(sqrtPriceX96, tick);
    }
    struct ModifyPositionParams {
        // the address that owns the position
        address owner;
        // the lower and upper tick of the position
        int24 tickLower;
        int24 tickUpper;
        // any change in liquidity
        int128 liquidityDelta;
    }
    /// @dev Effect some changes to a position
    /// @param params the position details and the change to the position's liquidity to effect
    /// @return position a storage pointer referencing the position with the given owner and tick range
    /// @return amount0 the amount of token0 owed to the pool, negative if the pool should pay the recipient
    /// @return amount1 the amount of token1 owed to the pool, negative if the pool should pay the recipient
    function _modifyPosition(ModifyPositionParams memory params)
        private
        noDelegateCall
        returns (
            Position.Info storage position,
            int256 amount0,
            int256 amount1
        )
    {
        checkTicks(params.tickLower, params.tickUpper);
        Slot0 memory _slot0 = slot0; // SLOAD for gas optimization
        position = _updatePosition(
            params.owner,
            params.tickLower,
            params.tickUpper,
            params.liquidityDelta,
            _slot0.tick
        );
        if (params.liquidityDelta != 0) {
            if (_slot0.tick < params.tickLower) {
                // current tick is below the passed range; liquidity can only become in range by crossing from left to
                // right, when we'll need _more_ token0 (it's becoming more valuable) so user must provide it
                amount0 = SqrtPriceMath.getAmount0Delta(
                    TickMath.getSqrtRatioAtTick(params.tickLower),
                    TickMath.getSqrtRatioAtTick(params.tickUpper),
                    params.liquidityDelta
                );
            } else if (_slot0.tick < params.tickUpper) {
                // current tick is inside the passed range
                uint128 liquidityBefore = liquidity; // SLOAD for gas optimization
                // write an oracle entry
                (slot0.observationIndex, slot0.observationCardinality) = observations.write(
                    _slot0.observationIndex,
                    _blockTimestamp(),
                    _slot0.tick,
                    liquidityBefore,
                    _slot0.observationCardinality,
                    _slot0.observationCardinalityNext
                );
                amount0 = SqrtPriceMath.getAmount0Delta(
                    _slot0.sqrtPriceX96,
                    TickMath.getSqrtRatioAtTick(params.tickUpper),
                    params.liquidityDelta
                );
                amount1 = SqrtPriceMath.getAmount1Delta(
                    TickMath.getSqrtRatioAtTick(params.tickLower),
                    _slot0.sqrtPriceX96,
                    params.liquidityDelta
                );
                liquidity = LiquidityMath.addDelta(liquidityBefore, params.liquidityDelta);
            } else {
                // current tick is above the passed range; liquidity can only become in range by crossing from right to
                // left, when we'll need _more_ token1 (it's becoming more valuable) so user must provide it
                amount1 = SqrtPriceMath.getAmount1Delta(
                    TickMath.getSqrtRatioAtTick(params.tickLower),
                    TickMath.getSqrtRatioAtTick(params.tickUpper),
                    params.liquidityDelta
                );
            }
        }
    }
    /// @dev Gets and updates a position with the given liquidity delta
    /// @param owner the owner of the position
    /// @param tickLower the lower tick of the position's tick range
    /// @param tickUpper the upper tick of the position's tick range
    /// @param tick the current tick, passed to avoid sloads
    function _updatePosition(
        address owner,
        int24 tickLower,
        int24 tickUpper,
        int128 liquidityDelta,
        int24 tick
    ) private returns (Position.Info storage position) {
        position = positions.get(owner, tickLower, tickUpper);
        uint256 _feeGrowthGlobal0X128 = feeGrowthGlobal0X128; // SLOAD for gas optimization
        uint256 _feeGrowthGlobal1X128 = feeGrowthGlobal1X128; // SLOAD for gas optimization
        // if we need to update the ticks, do it
        bool flippedLower;
        bool flippedUpper;
        if (liquidityDelta != 0) {
            uint32 time = _blockTimestamp();
            (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) =
                observations.observeSingle(
                    time,
                    0,
                    slot0.tick,
                    slot0.observationIndex,
                    liquidity,
                    slot0.observationCardinality
                );
            flippedLower = ticks.update(
                tickLower,
                tick,
                liquidityDelta,
                _feeGrowthGlobal0X128,
                _feeGrowthGlobal1X128,
                secondsPerLiquidityCumulativeX128,
                tickCumulative,
                time,
                false,
                maxLiquidityPerTick
            );
            flippedUpper = ticks.update(
                tickUpper,
                tick,
                liquidityDelta,
                _feeGrowthGlobal0X128,
                _feeGrowthGlobal1X128,
                secondsPerLiquidityCumulativeX128,
                tickCumulative,
                time,
                true,
                maxLiquidityPerTick
            );
            if (flippedLower) {
                tickBitmap.flipTick(tickLower, tickSpacing);
            }
            if (flippedUpper) {
                tickBitmap.flipTick(tickUpper, tickSpacing);
            }
        }
        (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) =
            ticks.getFeeGrowthInside(tickLower, tickUpper, tick, _feeGrowthGlobal0X128, _feeGrowthGlobal1X128);
        position.update(liquidityDelta, feeGrowthInside0X128, feeGrowthInside1X128);
        // clear any tick data that is no longer needed
        if (liquidityDelta < 0) {
            if (flippedLower) {
                ticks.clear(tickLower);
            }
            if (flippedUpper) {
                ticks.clear(tickUpper);
            }
        }
    }
    /// @inheritdoc IUniswapV3PoolActions
    /// @dev noDelegateCall is applied indirectly via _modifyPosition
    function mint(
        address recipient,
        int24 tickLower,
        int24 tickUpper,
        uint128 amount,
        bytes calldata data
    ) external override lock returns (uint256 amount0, uint256 amount1) {
        require(amount > 0);
        (, int256 amount0Int, int256 amount1Int) =
            _modifyPosition(
                ModifyPositionParams({
                    owner: recipient,
                    tickLower: tickLower,
                    tickUpper: tickUpper,
                    liquidityDelta: int256(amount).toInt128()
                })
            );
        amount0 = uint256(amount0Int);
        amount1 = uint256(amount1Int);
        uint256 balance0Before;
        uint256 balance1Before;
        if (amount0 > 0) balance0Before = balance0();
        if (amount1 > 0) balance1Before = balance1();
        IUniswapV3MintCallback(msg.sender).uniswapV3MintCallback(amount0, amount1, data);
        if (amount0 > 0) require(balance0Before.add(amount0) <= balance0(), 'M0');
        if (amount1 > 0) require(balance1Before.add(amount1) <= balance1(), 'M1');
        emit Mint(msg.sender, recipient, tickLower, tickUpper, amount, amount0, amount1);
    }
    /// @inheritdoc IUniswapV3PoolActions
    function collect(
        address recipient,
        int24 tickLower,
        int24 tickUpper,
        uint128 amount0Requested,
        uint128 amount1Requested
    ) external override lock returns (uint128 amount0, uint128 amount1) {
        // we don't need to checkTicks here, because invalid positions will never have non-zero tokensOwed{0,1}
        Position.Info storage position = positions.get(msg.sender, tickLower, tickUpper);
        amount0 = amount0Requested > position.tokensOwed0 ? position.tokensOwed0 : amount0Requested;
        amount1 = amount1Requested > position.tokensOwed1 ? position.tokensOwed1 : amount1Requested;
        if (amount0 > 0) {
            position.tokensOwed0 -= amount0;
            TransferHelper.safeTransfer(token0, recipient, amount0);
        }
        if (amount1 > 0) {
            position.tokensOwed1 -= amount1;
            TransferHelper.safeTransfer(token1, recipient, amount1);
        }
        emit Collect(msg.sender, recipient, tickLower, tickUpper, amount0, amount1);
    }
    /// @inheritdoc IUniswapV3PoolActions
    /// @dev noDelegateCall is applied indirectly via _modifyPosition
    function burn(
        int24 tickLower,
        int24 tickUpper,
        uint128 amount
    ) external override lock returns (uint256 amount0, uint256 amount1) {
        (Position.Info storage position, int256 amount0Int, int256 amount1Int) =
            _modifyPosition(
                ModifyPositionParams({
                    owner: msg.sender,
                    tickLower: tickLower,
                    tickUpper: tickUpper,
                    liquidityDelta: -int256(amount).toInt128()
                })
            );
        amount0 = uint256(-amount0Int);
        amount1 = uint256(-amount1Int);
        if (amount0 > 0 || amount1 > 0) {
            (position.tokensOwed0, position.tokensOwed1) = (
                position.tokensOwed0 + uint128(amount0),
                position.tokensOwed1 + uint128(amount1)
            );
        }
        emit Burn(msg.sender, tickLower, tickUpper, amount, amount0, amount1);
    }
    struct SwapCache {
        // the protocol fee for the input token
        uint8 feeProtocol;
        // liquidity at the beginning of the swap
        uint128 liquidityStart;
        // the timestamp of the current block
        uint32 blockTimestamp;
        // the current value of the tick accumulator, computed only if we cross an initialized tick
        int56 tickCumulative;
        // the current value of seconds per liquidity accumulator, computed only if we cross an initialized tick
        uint160 secondsPerLiquidityCumulativeX128;
        // whether we've computed and cached the above two accumulators
        bool computedLatestObservation;
    }
    // the top level state of the swap, the results of which are recorded in storage at the end
    struct SwapState {
        // the amount remaining to be swapped in/out of the input/output asset
        int256 amountSpecifiedRemaining;
        // the amount already swapped out/in of the output/input asset
        int256 amountCalculated;
        // current sqrt(price)
        uint160 sqrtPriceX96;
        // the tick associated with the current price
        int24 tick;
        // the global fee growth of the input token
        uint256 feeGrowthGlobalX128;
        // amount of input token paid as protocol fee
        uint128 protocolFee;
        // the current liquidity in range
        uint128 liquidity;
    }
    struct StepComputations {
        // the price at the beginning of the step
        uint160 sqrtPriceStartX96;
        // the next tick to swap to from the current tick in the swap direction
        int24 tickNext;
        // whether tickNext is initialized or not
        bool initialized;
        // sqrt(price) for the next tick (1/0)
        uint160 sqrtPriceNextX96;
        // how much is being swapped in in this step
        uint256 amountIn;
        // how much is being swapped out
        uint256 amountOut;
        // how much fee is being paid in
        uint256 feeAmount;
    }
    /// @inheritdoc IUniswapV3PoolActions
    function swap(
        address recipient,
        bool zeroForOne,
        int256 amountSpecified,
        uint160 sqrtPriceLimitX96,
        bytes calldata data
    ) external override noDelegateCall returns (int256 amount0, int256 amount1) {
        require(amountSpecified != 0, 'AS');
        Slot0 memory slot0Start = slot0;
        require(slot0Start.unlocked, 'LOK');
        require(
            zeroForOne
                ? sqrtPriceLimitX96 < slot0Start.sqrtPriceX96 && sqrtPriceLimitX96 > TickMath.MIN_SQRT_RATIO
                : sqrtPriceLimitX96 > slot0Start.sqrtPriceX96 && sqrtPriceLimitX96 < TickMath.MAX_SQRT_RATIO,
            'SPL'
        );
        slot0.unlocked = false;
        SwapCache memory cache =
            SwapCache({
                liquidityStart: liquidity,
                blockTimestamp: _blockTimestamp(),
                feeProtocol: zeroForOne ? (slot0Start.feeProtocol % 16) : (slot0Start.feeProtocol >> 4),
                secondsPerLiquidityCumulativeX128: 0,
                tickCumulative: 0,
                computedLatestObservation: false
            });
        bool exactInput = amountSpecified > 0;
        SwapState memory state =
            SwapState({
                amountSpecifiedRemaining: amountSpecified,
                amountCalculated: 0,
                sqrtPriceX96: slot0Start.sqrtPriceX96,
                tick: slot0Start.tick,
                feeGrowthGlobalX128: zeroForOne ? feeGrowthGlobal0X128 : feeGrowthGlobal1X128,
                protocolFee: 0,
                liquidity: cache.liquidityStart
            });
        // continue swapping as long as we haven't used the entire input/output and haven't reached the price limit
        while (state.amountSpecifiedRemaining != 0 && state.sqrtPriceX96 != sqrtPriceLimitX96) {
            StepComputations memory step;
            step.sqrtPriceStartX96 = state.sqrtPriceX96;
            (step.tickNext, step.initialized) = tickBitmap.nextInitializedTickWithinOneWord(
                state.tick,
                tickSpacing,
                zeroForOne
            );
            // ensure that we do not overshoot the min/max tick, as the tick bitmap is not aware of these bounds
            if (step.tickNext < TickMath.MIN_TICK) {
                step.tickNext = TickMath.MIN_TICK;
            } else if (step.tickNext > TickMath.MAX_TICK) {
                step.tickNext = TickMath.MAX_TICK;
            }
            // get the price for the next tick
            step.sqrtPriceNextX96 = TickMath.getSqrtRatioAtTick(step.tickNext);
            // compute values to swap to the target tick, price limit, or point where input/output amount is exhausted
            (state.sqrtPriceX96, step.amountIn, step.amountOut, step.feeAmount) = SwapMath.computeSwapStep(
                state.sqrtPriceX96,
                (zeroForOne ? step.sqrtPriceNextX96 < sqrtPriceLimitX96 : step.sqrtPriceNextX96 > sqrtPriceLimitX96)
                    ? sqrtPriceLimitX96
                    : step.sqrtPriceNextX96,
                state.liquidity,
                state.amountSpecifiedRemaining,
                fee
            );
            if (exactInput) {
                state.amountSpecifiedRemaining -= (step.amountIn + step.feeAmount).toInt256();
                state.amountCalculated = state.amountCalculated.sub(step.amountOut.toInt256());
            } else {
                state.amountSpecifiedRemaining += step.amountOut.toInt256();
                state.amountCalculated = state.amountCalculated.add((step.amountIn + step.feeAmount).toInt256());
            }
            // if the protocol fee is on, calculate how much is owed, decrement feeAmount, and increment protocolFee
            if (cache.feeProtocol > 0) {
                uint256 delta = step.feeAmount / cache.feeProtocol;
                step.feeAmount -= delta;
                state.protocolFee += uint128(delta);
            }
            // update global fee tracker
            if (state.liquidity > 0)
                state.feeGrowthGlobalX128 += FullMath.mulDiv(step.feeAmount, FixedPoint128.Q128, state.liquidity);
            // shift tick if we reached the next price
            if (state.sqrtPriceX96 == step.sqrtPriceNextX96) {
                // if the tick is initialized, run the tick transition
                if (step.initialized) {
                    // check for the placeholder value, which we replace with the actual value the first time the swap
                    // crosses an initialized tick
                    if (!cache.computedLatestObservation) {
                        (cache.tickCumulative, cache.secondsPerLiquidityCumulativeX128) = observations.observeSingle(
                            cache.blockTimestamp,
                            0,
                            slot0Start.tick,
                            slot0Start.observationIndex,
                            cache.liquidityStart,
                            slot0Start.observationCardinality
                        );
                        cache.computedLatestObservation = true;
                    }
                    int128 liquidityNet =
                        ticks.cross(
                            step.tickNext,
                            (zeroForOne ? state.feeGrowthGlobalX128 : feeGrowthGlobal0X128),
                            (zeroForOne ? feeGrowthGlobal1X128 : state.feeGrowthGlobalX128),
                            cache.secondsPerLiquidityCumulativeX128,
                            cache.tickCumulative,
                            cache.blockTimestamp
                        );
                    // if we're moving leftward, we interpret liquidityNet as the opposite sign
                    // safe because liquidityNet cannot be type(int128).min
                    if (zeroForOne) liquidityNet = -liquidityNet;
                    state.liquidity = LiquidityMath.addDelta(state.liquidity, liquidityNet);
                }
                state.tick = zeroForOne ? step.tickNext - 1 : step.tickNext;
            } else if (state.sqrtPriceX96 != step.sqrtPriceStartX96) {
                // recompute unless we're on a lower tick boundary (i.e. already transitioned ticks), and haven't moved
                state.tick = TickMath.getTickAtSqrtRatio(state.sqrtPriceX96);
            }
        }
        // update tick and write an oracle entry if the tick change
        if (state.tick != slot0Start.tick) {
            (uint16 observationIndex, uint16 observationCardinality) =
                observations.write(
                    slot0Start.observationIndex,
                    cache.blockTimestamp,
                    slot0Start.tick,
                    cache.liquidityStart,
                    slot0Start.observationCardinality,
                    slot0Start.observationCardinalityNext
                );
            (slot0.sqrtPriceX96, slot0.tick, slot0.observationIndex, slot0.observationCardinality) = (
                state.sqrtPriceX96,
                state.tick,
                observationIndex,
                observationCardinality
            );
        } else {
            // otherwise just update the price
            slot0.sqrtPriceX96 = state.sqrtPriceX96;
        }
        // update liquidity if it changed
        if (cache.liquidityStart != state.liquidity) liquidity = state.liquidity;
        // update fee growth global and, if necessary, protocol fees
        // overflow is acceptable, protocol has to withdraw before it hits type(uint128).max fees
        if (zeroForOne) {
            feeGrowthGlobal0X128 = state.feeGrowthGlobalX128;
            if (state.protocolFee > 0) protocolFees.token0 += state.protocolFee;
        } else {
            feeGrowthGlobal1X128 = state.feeGrowthGlobalX128;
            if (state.protocolFee > 0) protocolFees.token1 += state.protocolFee;
        }
        (amount0, amount1) = zeroForOne == exactInput
            ? (amountSpecified - state.amountSpecifiedRemaining, state.amountCalculated)
            : (state.amountCalculated, amountSpecified - state.amountSpecifiedRemaining);
        // do the transfers and collect payment
        if (zeroForOne) {
            if (amount1 < 0) TransferHelper.safeTransfer(token1, recipient, uint256(-amount1));
            uint256 balance0Before = balance0();
            IUniswapV3SwapCallback(msg.sender).uniswapV3SwapCallback(amount0, amount1, data);
            require(balance0Before.add(uint256(amount0)) <= balance0(), 'IIA');
        } else {
            if (amount0 < 0) TransferHelper.safeTransfer(token0, recipient, uint256(-amount0));
            uint256 balance1Before = balance1();
            IUniswapV3SwapCallback(msg.sender).uniswapV3SwapCallback(amount0, amount1, data);
            require(balance1Before.add(uint256(amount1)) <= balance1(), 'IIA');
        }
        emit Swap(msg.sender, recipient, amount0, amount1, state.sqrtPriceX96, state.liquidity, state.tick);
        slot0.unlocked = true;
    }
    /// @inheritdoc IUniswapV3PoolActions
    function flash(
        address recipient,
        uint256 amount0,
        uint256 amount1,
        bytes calldata data
    ) external override lock noDelegateCall {
        uint128 _liquidity = liquidity;
        require(_liquidity > 0, 'L');
        uint256 fee0 = FullMath.mulDivRoundingUp(amount0, fee, 1e6);
        uint256 fee1 = FullMath.mulDivRoundingUp(amount1, fee, 1e6);
        uint256 balance0Before = balance0();
        uint256 balance1Before = balance1();
        if (amount0 > 0) TransferHelper.safeTransfer(token0, recipient, amount0);
        if (amount1 > 0) TransferHelper.safeTransfer(token1, recipient, amount1);
        IUniswapV3FlashCallback(msg.sender).uniswapV3FlashCallback(fee0, fee1, data);
        uint256 balance0After = balance0();
        uint256 balance1After = balance1();
        require(balance0Before.add(fee0) <= balance0After, 'F0');
        require(balance1Before.add(fee1) <= balance1After, 'F1');
        // sub is safe because we know balanceAfter is gt balanceBefore by at least fee
        uint256 paid0 = balance0After - balance0Before;
        uint256 paid1 = balance1After - balance1Before;
        if (paid0 > 0) {
            uint8 feeProtocol0 = slot0.feeProtocol % 16;
            uint256 fees0 = feeProtocol0 == 0 ? 0 : paid0 / feeProtocol0;
            if (uint128(fees0) > 0) protocolFees.token0 += uint128(fees0);
            feeGrowthGlobal0X128 += FullMath.mulDiv(paid0 - fees0, FixedPoint128.Q128, _liquidity);
        }
        if (paid1 > 0) {
            uint8 feeProtocol1 = slot0.feeProtocol >> 4;
            uint256 fees1 = feeProtocol1 == 0 ? 0 : paid1 / feeProtocol1;
            if (uint128(fees1) > 0) protocolFees.token1 += uint128(fees1);
            feeGrowthGlobal1X128 += FullMath.mulDiv(paid1 - fees1, FixedPoint128.Q128, _liquidity);
        }
        emit Flash(msg.sender, recipient, amount0, amount1, paid0, paid1);
    }
    /// @inheritdoc IUniswapV3PoolOwnerActions
    function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external override lock onlyFactoryOwner {
        require(
            (feeProtocol0 == 0 || (feeProtocol0 >= 4 && feeProtocol0 <= 10)) &&
                (feeProtocol1 == 0 || (feeProtocol1 >= 4 && feeProtocol1 <= 10))
        );
        uint8 feeProtocolOld = slot0.feeProtocol;
        slot0.feeProtocol = feeProtocol0 + (feeProtocol1 << 4);
        emit SetFeeProtocol(feeProtocolOld % 16, feeProtocolOld >> 4, feeProtocol0, feeProtocol1);
    }
    /// @inheritdoc IUniswapV3PoolOwnerActions
    function collectProtocol(
        address recipient,
        uint128 amount0Requested,
        uint128 amount1Requested
    ) external override lock onlyFactoryOwner returns (uint128 amount0, uint128 amount1) {
        amount0 = amount0Requested > protocolFees.token0 ? protocolFees.token0 : amount0Requested;
        amount1 = amount1Requested > protocolFees.token1 ? protocolFees.token1 : amount1Requested;
        if (amount0 > 0) {
            if (amount0 == protocolFees.token0) amount0--; // ensure that the slot is not cleared, for gas savings
            protocolFees.token0 -= amount0;
            TransferHelper.safeTransfer(token0, recipient, amount0);
        }
        if (amount1 > 0) {
            if (amount1 == protocolFees.token1) amount1--; // ensure that the slot is not cleared, for gas savings
            protocolFees.token1 -= amount1;
            TransferHelper.safeTransfer(token1, recipient, amount1);
        }
        emit CollectProtocol(msg.sender, recipient, amount0, amount1);
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import './pool/IUniswapV3PoolImmutables.sol';
import './pool/IUniswapV3PoolState.sol';
import './pool/IUniswapV3PoolDerivedState.sol';
import './pool/IUniswapV3PoolActions.sol';
import './pool/IUniswapV3PoolOwnerActions.sol';
import './pool/IUniswapV3PoolEvents.sol';
/// @title The interface for a Uniswap V3 Pool
/// @notice A Uniswap pool facilitates swapping and automated market making between any two assets that strictly conform
/// to the ERC20 specification
/// @dev The pool interface is broken up into many smaller pieces
interface IUniswapV3Pool is
    IUniswapV3PoolImmutables,
    IUniswapV3PoolState,
    IUniswapV3PoolDerivedState,
    IUniswapV3PoolActions,
    IUniswapV3PoolOwnerActions,
    IUniswapV3PoolEvents
{
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
/// @title Prevents delegatecall to a contract
/// @notice Base contract that provides a modifier for preventing delegatecall to methods in a child contract
abstract contract NoDelegateCall {
    /// @dev The original address of this contract
    address private immutable original;
    constructor() {
        // Immutables are computed in the init code of the contract, and then inlined into the deployed bytecode.
        // In other words, this variable won't change when it's checked at runtime.
        original = address(this);
    }
    /// @dev Private method is used instead of inlining into modifier because modifiers are copied into each method,
    ///     and the use of immutable means the address bytes are copied in every place the modifier is used.
    function checkNotDelegateCall() private view {
        require(address(this) == original);
    }
    /// @notice Prevents delegatecall into the modified method
    modifier noDelegateCall() {
        checkNotDelegateCall();
        _;
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.0;
/// @title Optimized overflow and underflow safe math operations
/// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
library LowGasSafeMath {
    /// @notice Returns x + y, reverts if sum overflows uint256
    /// @param x The augend
    /// @param y The addend
    /// @return z The sum of x and y
    function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x + y) >= x);
    }
    /// @notice Returns x - y, reverts if underflows
    /// @param x The minuend
    /// @param y The subtrahend
    /// @return z The difference of x and y
    function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x - y) <= x);
    }
    /// @notice Returns x * y, reverts if overflows
    /// @param x The multiplicand
    /// @param y The multiplier
    /// @return z The product of x and y
    function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require(x == 0 || (z = x * y) / x == y);
    }
    /// @notice Returns x + y, reverts if overflows or underflows
    /// @param x The augend
    /// @param y The addend
    /// @return z The sum of x and y
    function add(int256 x, int256 y) internal pure returns (int256 z) {
        require((z = x + y) >= x == (y >= 0));
    }
    /// @notice Returns x - y, reverts if overflows or underflows
    /// @param x The minuend
    /// @param y The subtrahend
    /// @return z The difference of x and y
    function sub(int256 x, int256 y) internal pure returns (int256 z) {
        require((z = x - y) <= x == (y >= 0));
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Safe casting methods
/// @notice Contains methods for safely casting between types
library SafeCast {
    /// @notice Cast a uint256 to a uint160, revert on overflow
    /// @param y The uint256 to be downcasted
    /// @return z The downcasted integer, now type uint160
    function toUint160(uint256 y) internal pure returns (uint160 z) {
        require((z = uint160(y)) == y);
    }
    /// @notice Cast a int256 to a int128, revert on overflow or underflow
    /// @param y The int256 to be downcasted
    /// @return z The downcasted integer, now type int128
    function toInt128(int256 y) internal pure returns (int128 z) {
        require((z = int128(y)) == y);
    }
    /// @notice Cast a uint256 to a int256, revert on overflow
    /// @param y The uint256 to be casted
    /// @return z The casted integer, now type int256
    function toInt256(uint256 y) internal pure returns (int256 z) {
        require(y < 2**255);
        z = int256(y);
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './LowGasSafeMath.sol';
import './SafeCast.sol';
import './TickMath.sol';
import './LiquidityMath.sol';
/// @title Tick
/// @notice Contains functions for managing tick processes and relevant calculations
library Tick {
    using LowGasSafeMath for int256;
    using SafeCast for int256;
    // info stored for each initialized individual tick
    struct Info {
        // the total position liquidity that references this tick
        uint128 liquidityGross;
        // amount of net liquidity added (subtracted) when tick is crossed from left to right (right to left),
        int128 liquidityNet;
        // fee growth per unit of liquidity on the _other_ side of this tick (relative to the current tick)
        // only has relative meaning, not absolute — the value depends on when the tick is initialized
        uint256 feeGrowthOutside0X128;
        uint256 feeGrowthOutside1X128;
        // the cumulative tick value on the other side of the tick
        int56 tickCumulativeOutside;
        // the seconds per unit of liquidity on the _other_ side of this tick (relative to the current tick)
        // only has relative meaning, not absolute — the value depends on when the tick is initialized
        uint160 secondsPerLiquidityOutsideX128;
        // the seconds spent on the other side of the tick (relative to the current tick)
        // only has relative meaning, not absolute — the value depends on when the tick is initialized
        uint32 secondsOutside;
        // true iff the tick is initialized, i.e. the value is exactly equivalent to the expression liquidityGross != 0
        // these 8 bits are set to prevent fresh sstores when crossing newly initialized ticks
        bool initialized;
    }
    /// @notice Derives max liquidity per tick from given tick spacing
    /// @dev Executed within the pool constructor
    /// @param tickSpacing The amount of required tick separation, realized in multiples of `tickSpacing`
    ///     e.g., a tickSpacing of 3 requires ticks to be initialized every 3rd tick i.e., ..., -6, -3, 0, 3, 6, ...
    /// @return The max liquidity per tick
    function tickSpacingToMaxLiquidityPerTick(int24 tickSpacing) internal pure returns (uint128) {
        int24 minTick = (TickMath.MIN_TICK / tickSpacing) * tickSpacing;
        int24 maxTick = (TickMath.MAX_TICK / tickSpacing) * tickSpacing;
        uint24 numTicks = uint24((maxTick - minTick) / tickSpacing) + 1;
        return type(uint128).max / numTicks;
    }
    /// @notice Retrieves fee growth data
    /// @param self The mapping containing all tick information for initialized ticks
    /// @param tickLower The lower tick boundary of the position
    /// @param tickUpper The upper tick boundary of the position
    /// @param tickCurrent The current tick
    /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
    /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
    /// @return feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
    /// @return feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
    function getFeeGrowthInside(
        mapping(int24 => Tick.Info) storage self,
        int24 tickLower,
        int24 tickUpper,
        int24 tickCurrent,
        uint256 feeGrowthGlobal0X128,
        uint256 feeGrowthGlobal1X128
    ) internal view returns (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) {
        Info storage lower = self[tickLower];
        Info storage upper = self[tickUpper];
        // calculate fee growth below
        uint256 feeGrowthBelow0X128;
        uint256 feeGrowthBelow1X128;
        if (tickCurrent >= tickLower) {
            feeGrowthBelow0X128 = lower.feeGrowthOutside0X128;
            feeGrowthBelow1X128 = lower.feeGrowthOutside1X128;
        } else {
            feeGrowthBelow0X128 = feeGrowthGlobal0X128 - lower.feeGrowthOutside0X128;
            feeGrowthBelow1X128 = feeGrowthGlobal1X128 - lower.feeGrowthOutside1X128;
        }
        // calculate fee growth above
        uint256 feeGrowthAbove0X128;
        uint256 feeGrowthAbove1X128;
        if (tickCurrent < tickUpper) {
            feeGrowthAbove0X128 = upper.feeGrowthOutside0X128;
            feeGrowthAbove1X128 = upper.feeGrowthOutside1X128;
        } else {
            feeGrowthAbove0X128 = feeGrowthGlobal0X128 - upper.feeGrowthOutside0X128;
            feeGrowthAbove1X128 = feeGrowthGlobal1X128 - upper.feeGrowthOutside1X128;
        }
        feeGrowthInside0X128 = feeGrowthGlobal0X128 - feeGrowthBelow0X128 - feeGrowthAbove0X128;
        feeGrowthInside1X128 = feeGrowthGlobal1X128 - feeGrowthBelow1X128 - feeGrowthAbove1X128;
    }
    /// @notice Updates a tick and returns true if the tick was flipped from initialized to uninitialized, or vice versa
    /// @param self The mapping containing all tick information for initialized ticks
    /// @param tick The tick that will be updated
    /// @param tickCurrent The current tick
    /// @param liquidityDelta A new amount of liquidity to be added (subtracted) when tick is crossed from left to right (right to left)
    /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
    /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
    /// @param secondsPerLiquidityCumulativeX128 The all-time seconds per max(1, liquidity) of the pool
    /// @param time The current block timestamp cast to a uint32
    /// @param upper true for updating a position's upper tick, or false for updating a position's lower tick
    /// @param maxLiquidity The maximum liquidity allocation for a single tick
    /// @return flipped Whether the tick was flipped from initialized to uninitialized, or vice versa
    function update(
        mapping(int24 => Tick.Info) storage self,
        int24 tick,
        int24 tickCurrent,
        int128 liquidityDelta,
        uint256 feeGrowthGlobal0X128,
        uint256 feeGrowthGlobal1X128,
        uint160 secondsPerLiquidityCumulativeX128,
        int56 tickCumulative,
        uint32 time,
        bool upper,
        uint128 maxLiquidity
    ) internal returns (bool flipped) {
        Tick.Info storage info = self[tick];
        uint128 liquidityGrossBefore = info.liquidityGross;
        uint128 liquidityGrossAfter = LiquidityMath.addDelta(liquidityGrossBefore, liquidityDelta);
        require(liquidityGrossAfter <= maxLiquidity, 'LO');
        flipped = (liquidityGrossAfter == 0) != (liquidityGrossBefore == 0);
        if (liquidityGrossBefore == 0) {
            // by convention, we assume that all growth before a tick was initialized happened _below_ the tick
            if (tick <= tickCurrent) {
                info.feeGrowthOutside0X128 = feeGrowthGlobal0X128;
                info.feeGrowthOutside1X128 = feeGrowthGlobal1X128;
                info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128;
                info.tickCumulativeOutside = tickCumulative;
                info.secondsOutside = time;
            }
            info.initialized = true;
        }
        info.liquidityGross = liquidityGrossAfter;
        // when the lower (upper) tick is crossed left to right (right to left), liquidity must be added (removed)
        info.liquidityNet = upper
            ? int256(info.liquidityNet).sub(liquidityDelta).toInt128()
            : int256(info.liquidityNet).add(liquidityDelta).toInt128();
    }
    /// @notice Clears tick data
    /// @param self The mapping containing all initialized tick information for initialized ticks
    /// @param tick The tick that will be cleared
    function clear(mapping(int24 => Tick.Info) storage self, int24 tick) internal {
        delete self[tick];
    }
    /// @notice Transitions to next tick as needed by price movement
    /// @param self The mapping containing all tick information for initialized ticks
    /// @param tick The destination tick of the transition
    /// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
    /// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
    /// @param secondsPerLiquidityCumulativeX128 The current seconds per liquidity
    /// @param time The current block.timestamp
    /// @return liquidityNet The amount of liquidity added (subtracted) when tick is crossed from left to right (right to left)
    function cross(
        mapping(int24 => Tick.Info) storage self,
        int24 tick,
        uint256 feeGrowthGlobal0X128,
        uint256 feeGrowthGlobal1X128,
        uint160 secondsPerLiquidityCumulativeX128,
        int56 tickCumulative,
        uint32 time
    ) internal returns (int128 liquidityNet) {
        Tick.Info storage info = self[tick];
        info.feeGrowthOutside0X128 = feeGrowthGlobal0X128 - info.feeGrowthOutside0X128;
        info.feeGrowthOutside1X128 = feeGrowthGlobal1X128 - info.feeGrowthOutside1X128;
        info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128 - info.secondsPerLiquidityOutsideX128;
        info.tickCumulativeOutside = tickCumulative - info.tickCumulativeOutside;
        info.secondsOutside = time - info.secondsOutside;
        liquidityNet = info.liquidityNet;
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './BitMath.sol';
/// @title Packed tick initialized state library
/// @notice Stores a packed mapping of tick index to its initialized state
/// @dev The mapping uses int16 for keys since ticks are represented as int24 and there are 256 (2^8) values per word.
library TickBitmap {
    /// @notice Computes the position in the mapping where the initialized bit for a tick lives
    /// @param tick The tick for which to compute the position
    /// @return wordPos The key in the mapping containing the word in which the bit is stored
    /// @return bitPos The bit position in the word where the flag is stored
    function position(int24 tick) private pure returns (int16 wordPos, uint8 bitPos) {
        wordPos = int16(tick >> 8);
        bitPos = uint8(tick % 256);
    }
    /// @notice Flips the initialized state for a given tick from false to true, or vice versa
    /// @param self The mapping in which to flip the tick
    /// @param tick The tick to flip
    /// @param tickSpacing The spacing between usable ticks
    function flipTick(
        mapping(int16 => uint256) storage self,
        int24 tick,
        int24 tickSpacing
    ) internal {
        require(tick % tickSpacing == 0); // ensure that the tick is spaced
        (int16 wordPos, uint8 bitPos) = position(tick / tickSpacing);
        uint256 mask = 1 << bitPos;
        self[wordPos] ^= mask;
    }
    /// @notice Returns the next initialized tick contained in the same word (or adjacent word) as the tick that is either
    /// to the left (less than or equal to) or right (greater than) of the given tick
    /// @param self The mapping in which to compute the next initialized tick
    /// @param tick The starting tick
    /// @param tickSpacing The spacing between usable ticks
    /// @param lte Whether to search for the next initialized tick to the left (less than or equal to the starting tick)
    /// @return next The next initialized or uninitialized tick up to 256 ticks away from the current tick
    /// @return initialized Whether the next tick is initialized, as the function only searches within up to 256 ticks
    function nextInitializedTickWithinOneWord(
        mapping(int16 => uint256) storage self,
        int24 tick,
        int24 tickSpacing,
        bool lte
    ) internal view returns (int24 next, bool initialized) {
        int24 compressed = tick / tickSpacing;
        if (tick < 0 && tick % tickSpacing != 0) compressed--; // round towards negative infinity
        if (lte) {
            (int16 wordPos, uint8 bitPos) = position(compressed);
            // all the 1s at or to the right of the current bitPos
            uint256 mask = (1 << bitPos) - 1 + (1 << bitPos);
            uint256 masked = self[wordPos] & mask;
            // if there are no initialized ticks to the right of or at the current tick, return rightmost in the word
            initialized = masked != 0;
            // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
            next = initialized
                ? (compressed - int24(bitPos - BitMath.mostSignificantBit(masked))) * tickSpacing
                : (compressed - int24(bitPos)) * tickSpacing;
        } else {
            // start from the word of the next tick, since the current tick state doesn't matter
            (int16 wordPos, uint8 bitPos) = position(compressed + 1);
            // all the 1s at or to the left of the bitPos
            uint256 mask = ~((1 << bitPos) - 1);
            uint256 masked = self[wordPos] & mask;
            // if there are no initialized ticks to the left of the current tick, return leftmost in the word
            initialized = masked != 0;
            // overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
            next = initialized
                ? (compressed + 1 + int24(BitMath.leastSignificantBit(masked) - bitPos)) * tickSpacing
                : (compressed + 1 + int24(type(uint8).max - bitPos)) * tickSpacing;
        }
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './FullMath.sol';
import './FixedPoint128.sol';
import './LiquidityMath.sol';
/// @title Position
/// @notice Positions represent an owner address' liquidity between a lower and upper tick boundary
/// @dev Positions store additional state for tracking fees owed to the position
library Position {
    // info stored for each user's position
    struct Info {
        // the amount of liquidity owned by this position
        uint128 liquidity;
        // fee growth per unit of liquidity as of the last update to liquidity or fees owed
        uint256 feeGrowthInside0LastX128;
        uint256 feeGrowthInside1LastX128;
        // the fees owed to the position owner in token0/token1
        uint128 tokensOwed0;
        uint128 tokensOwed1;
    }
    /// @notice Returns the Info struct of a position, given an owner and position boundaries
    /// @param self The mapping containing all user positions
    /// @param owner The address of the position owner
    /// @param tickLower The lower tick boundary of the position
    /// @param tickUpper The upper tick boundary of the position
    /// @return position The position info struct of the given owners' position
    function get(
        mapping(bytes32 => Info) storage self,
        address owner,
        int24 tickLower,
        int24 tickUpper
    ) internal view returns (Position.Info storage position) {
        position = self[keccak256(abi.encodePacked(owner, tickLower, tickUpper))];
    }
    /// @notice Credits accumulated fees to a user's position
    /// @param self The individual position to update
    /// @param liquidityDelta The change in pool liquidity as a result of the position update
    /// @param feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
    /// @param feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
    function update(
        Info storage self,
        int128 liquidityDelta,
        uint256 feeGrowthInside0X128,
        uint256 feeGrowthInside1X128
    ) internal {
        Info memory _self = self;
        uint128 liquidityNext;
        if (liquidityDelta == 0) {
            require(_self.liquidity > 0, 'NP'); // disallow pokes for 0 liquidity positions
            liquidityNext = _self.liquidity;
        } else {
            liquidityNext = LiquidityMath.addDelta(_self.liquidity, liquidityDelta);
        }
        // calculate accumulated fees
        uint128 tokensOwed0 =
            uint128(
                FullMath.mulDiv(
                    feeGrowthInside0X128 - _self.feeGrowthInside0LastX128,
                    _self.liquidity,
                    FixedPoint128.Q128
                )
            );
        uint128 tokensOwed1 =
            uint128(
                FullMath.mulDiv(
                    feeGrowthInside1X128 - _self.feeGrowthInside1LastX128,
                    _self.liquidity,
                    FixedPoint128.Q128
                )
            );
        // update the position
        if (liquidityDelta != 0) self.liquidity = liquidityNext;
        self.feeGrowthInside0LastX128 = feeGrowthInside0X128;
        self.feeGrowthInside1LastX128 = feeGrowthInside1X128;
        if (tokensOwed0 > 0 || tokensOwed1 > 0) {
            // overflow is acceptable, have to withdraw before you hit type(uint128).max fees
            self.tokensOwed0 += tokensOwed0;
            self.tokensOwed1 += tokensOwed1;
        }
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
/// @title Oracle
/// @notice Provides price and liquidity data useful for a wide variety of system designs
/// @dev Instances of stored oracle data, "observations", are collected in the oracle array
/// Every pool is initialized with an oracle array length of 1. Anyone can pay the SSTOREs to increase the
/// maximum length of the oracle array. New slots will be added when the array is fully populated.
/// Observations are overwritten when the full length of the oracle array is populated.
/// The most recent observation is available, independent of the length of the oracle array, by passing 0 to observe()
library Oracle {
    struct Observation {
        // the block timestamp of the observation
        uint32 blockTimestamp;
        // the tick accumulator, i.e. tick * time elapsed since the pool was first initialized
        int56 tickCumulative;
        // the seconds per liquidity, i.e. seconds elapsed / max(1, liquidity) since the pool was first initialized
        uint160 secondsPerLiquidityCumulativeX128;
        // whether or not the observation is initialized
        bool initialized;
    }
    /// @notice Transforms a previous observation into a new observation, given the passage of time and the current tick and liquidity values
    /// @dev blockTimestamp _must_ be chronologically equal to or greater than last.blockTimestamp, safe for 0 or 1 overflows
    /// @param last The specified observation to be transformed
    /// @param blockTimestamp The timestamp of the new observation
    /// @param tick The active tick at the time of the new observation
    /// @param liquidity The total in-range liquidity at the time of the new observation
    /// @return Observation The newly populated observation
    function transform(
        Observation memory last,
        uint32 blockTimestamp,
        int24 tick,
        uint128 liquidity
    ) private pure returns (Observation memory) {
        uint32 delta = blockTimestamp - last.blockTimestamp;
        return
            Observation({
                blockTimestamp: blockTimestamp,
                tickCumulative: last.tickCumulative + int56(tick) * delta,
                secondsPerLiquidityCumulativeX128: last.secondsPerLiquidityCumulativeX128 +
                    ((uint160(delta) << 128) / (liquidity > 0 ? liquidity : 1)),
                initialized: true
            });
    }
    /// @notice Initialize the oracle array by writing the first slot. Called once for the lifecycle of the observations array
    /// @param self The stored oracle array
    /// @param time The time of the oracle initialization, via block.timestamp truncated to uint32
    /// @return cardinality The number of populated elements in the oracle array
    /// @return cardinalityNext The new length of the oracle array, independent of population
    function initialize(Observation[65535] storage self, uint32 time)
        internal
        returns (uint16 cardinality, uint16 cardinalityNext)
    {
        self[0] = Observation({
            blockTimestamp: time,
            tickCumulative: 0,
            secondsPerLiquidityCumulativeX128: 0,
            initialized: true
        });
        return (1, 1);
    }
    /// @notice Writes an oracle observation to the array
    /// @dev Writable at most once per block. Index represents the most recently written element. cardinality and index must be tracked externally.
    /// If the index is at the end of the allowable array length (according to cardinality), and the next cardinality
    /// is greater than the current one, cardinality may be increased. This restriction is created to preserve ordering.
    /// @param self The stored oracle array
    /// @param index The index of the observation that was most recently written to the observations array
    /// @param blockTimestamp The timestamp of the new observation
    /// @param tick The active tick at the time of the new observation
    /// @param liquidity The total in-range liquidity at the time of the new observation
    /// @param cardinality The number of populated elements in the oracle array
    /// @param cardinalityNext The new length of the oracle array, independent of population
    /// @return indexUpdated The new index of the most recently written element in the oracle array
    /// @return cardinalityUpdated The new cardinality of the oracle array
    function write(
        Observation[65535] storage self,
        uint16 index,
        uint32 blockTimestamp,
        int24 tick,
        uint128 liquidity,
        uint16 cardinality,
        uint16 cardinalityNext
    ) internal returns (uint16 indexUpdated, uint16 cardinalityUpdated) {
        Observation memory last = self[index];
        // early return if we've already written an observation this block
        if (last.blockTimestamp == blockTimestamp) return (index, cardinality);
        // if the conditions are right, we can bump the cardinality
        if (cardinalityNext > cardinality && index == (cardinality - 1)) {
            cardinalityUpdated = cardinalityNext;
        } else {
            cardinalityUpdated = cardinality;
        }
        indexUpdated = (index + 1) % cardinalityUpdated;
        self[indexUpdated] = transform(last, blockTimestamp, tick, liquidity);
    }
    /// @notice Prepares the oracle array to store up to `next` observations
    /// @param self The stored oracle array
    /// @param current The current next cardinality of the oracle array
    /// @param next The proposed next cardinality which will be populated in the oracle array
    /// @return next The next cardinality which will be populated in the oracle array
    function grow(
        Observation[65535] storage self,
        uint16 current,
        uint16 next
    ) internal returns (uint16) {
        require(current > 0, 'I');
        // no-op if the passed next value isn't greater than the current next value
        if (next <= current) return current;
        // store in each slot to prevent fresh SSTOREs in swaps
        // this data will not be used because the initialized boolean is still false
        for (uint16 i = current; i < next; i++) self[i].blockTimestamp = 1;
        return next;
    }
    /// @notice comparator for 32-bit timestamps
    /// @dev safe for 0 or 1 overflows, a and b _must_ be chronologically before or equal to time
    /// @param time A timestamp truncated to 32 bits
    /// @param a A comparison timestamp from which to determine the relative position of `time`
    /// @param b From which to determine the relative position of `time`
    /// @return bool Whether `a` is chronologically <= `b`
    function lte(
        uint32 time,
        uint32 a,
        uint32 b
    ) private pure returns (bool) {
        // if there hasn't been overflow, no need to adjust
        if (a <= time && b <= time) return a <= b;
        uint256 aAdjusted = a > time ? a : a + 2**32;
        uint256 bAdjusted = b > time ? b : b + 2**32;
        return aAdjusted <= bAdjusted;
    }
    /// @notice Fetches the observations beforeOrAt and atOrAfter a target, i.e. where [beforeOrAt, atOrAfter] is satisfied.
    /// The result may be the same observation, or adjacent observations.
    /// @dev The answer must be contained in the array, used when the target is located within the stored observation
    /// boundaries: older than the most recent observation and younger, or the same age as, the oldest observation
    /// @param self The stored oracle array
    /// @param time The current block.timestamp
    /// @param target The timestamp at which the reserved observation should be for
    /// @param index The index of the observation that was most recently written to the observations array
    /// @param cardinality The number of populated elements in the oracle array
    /// @return beforeOrAt The observation recorded before, or at, the target
    /// @return atOrAfter The observation recorded at, or after, the target
    function binarySearch(
        Observation[65535] storage self,
        uint32 time,
        uint32 target,
        uint16 index,
        uint16 cardinality
    ) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
        uint256 l = (index + 1) % cardinality; // oldest observation
        uint256 r = l + cardinality - 1; // newest observation
        uint256 i;
        while (true) {
            i = (l + r) / 2;
            beforeOrAt = self[i % cardinality];
            // we've landed on an uninitialized tick, keep searching higher (more recently)
            if (!beforeOrAt.initialized) {
                l = i + 1;
                continue;
            }
            atOrAfter = self[(i + 1) % cardinality];
            bool targetAtOrAfter = lte(time, beforeOrAt.blockTimestamp, target);
            // check if we've found the answer!
            if (targetAtOrAfter && lte(time, target, atOrAfter.blockTimestamp)) break;
            if (!targetAtOrAfter) r = i - 1;
            else l = i + 1;
        }
    }
    /// @notice Fetches the observations beforeOrAt and atOrAfter a given target, i.e. where [beforeOrAt, atOrAfter] is satisfied
    /// @dev Assumes there is at least 1 initialized observation.
    /// Used by observeSingle() to compute the counterfactual accumulator values as of a given block timestamp.
    /// @param self The stored oracle array
    /// @param time The current block.timestamp
    /// @param target The timestamp at which the reserved observation should be for
    /// @param tick The active tick at the time of the returned or simulated observation
    /// @param index The index of the observation that was most recently written to the observations array
    /// @param liquidity The total pool liquidity at the time of the call
    /// @param cardinality The number of populated elements in the oracle array
    /// @return beforeOrAt The observation which occurred at, or before, the given timestamp
    /// @return atOrAfter The observation which occurred at, or after, the given timestamp
    function getSurroundingObservations(
        Observation[65535] storage self,
        uint32 time,
        uint32 target,
        int24 tick,
        uint16 index,
        uint128 liquidity,
        uint16 cardinality
    ) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
        // optimistically set before to the newest observation
        beforeOrAt = self[index];
        // if the target is chronologically at or after the newest observation, we can early return
        if (lte(time, beforeOrAt.blockTimestamp, target)) {
            if (beforeOrAt.blockTimestamp == target) {
                // if newest observation equals target, we're in the same block, so we can ignore atOrAfter
                return (beforeOrAt, atOrAfter);
            } else {
                // otherwise, we need to transform
                return (beforeOrAt, transform(beforeOrAt, target, tick, liquidity));
            }
        }
        // now, set before to the oldest observation
        beforeOrAt = self[(index + 1) % cardinality];
        if (!beforeOrAt.initialized) beforeOrAt = self[0];
        // ensure that the target is chronologically at or after the oldest observation
        require(lte(time, beforeOrAt.blockTimestamp, target), 'OLD');
        // if we've reached this point, we have to binary search
        return binarySearch(self, time, target, index, cardinality);
    }
    /// @dev Reverts if an observation at or before the desired observation timestamp does not exist.
    /// 0 may be passed as `secondsAgo' to return the current cumulative values.
    /// If called with a timestamp falling between two observations, returns the counterfactual accumulator values
    /// at exactly the timestamp between the two observations.
    /// @param self The stored oracle array
    /// @param time The current block timestamp
    /// @param secondsAgo The amount of time to look back, in seconds, at which point to return an observation
    /// @param tick The current tick
    /// @param index The index of the observation that was most recently written to the observations array
    /// @param liquidity The current in-range pool liquidity
    /// @param cardinality The number of populated elements in the oracle array
    /// @return tickCumulative The tick * time elapsed since the pool was first initialized, as of `secondsAgo`
    /// @return secondsPerLiquidityCumulativeX128 The time elapsed / max(1, liquidity) since the pool was first initialized, as of `secondsAgo`
    function observeSingle(
        Observation[65535] storage self,
        uint32 time,
        uint32 secondsAgo,
        int24 tick,
        uint16 index,
        uint128 liquidity,
        uint16 cardinality
    ) internal view returns (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) {
        if (secondsAgo == 0) {
            Observation memory last = self[index];
            if (last.blockTimestamp != time) last = transform(last, time, tick, liquidity);
            return (last.tickCumulative, last.secondsPerLiquidityCumulativeX128);
        }
        uint32 target = time - secondsAgo;
        (Observation memory beforeOrAt, Observation memory atOrAfter) =
            getSurroundingObservations(self, time, target, tick, index, liquidity, cardinality);
        if (target == beforeOrAt.blockTimestamp) {
            // we're at the left boundary
            return (beforeOrAt.tickCumulative, beforeOrAt.secondsPerLiquidityCumulativeX128);
        } else if (target == atOrAfter.blockTimestamp) {
            // we're at the right boundary
            return (atOrAfter.tickCumulative, atOrAfter.secondsPerLiquidityCumulativeX128);
        } else {
            // we're in the middle
            uint32 observationTimeDelta = atOrAfter.blockTimestamp - beforeOrAt.blockTimestamp;
            uint32 targetDelta = target - beforeOrAt.blockTimestamp;
            return (
                beforeOrAt.tickCumulative +
                    ((atOrAfter.tickCumulative - beforeOrAt.tickCumulative) / observationTimeDelta) *
                    targetDelta,
                beforeOrAt.secondsPerLiquidityCumulativeX128 +
                    uint160(
                        (uint256(
                            atOrAfter.secondsPerLiquidityCumulativeX128 - beforeOrAt.secondsPerLiquidityCumulativeX128
                        ) * targetDelta) / observationTimeDelta
                    )
            );
        }
    }
    /// @notice Returns the accumulator values as of each time seconds ago from the given time in the array of `secondsAgos`
    /// @dev Reverts if `secondsAgos` > oldest observation
    /// @param self The stored oracle array
    /// @param time The current block.timestamp
    /// @param secondsAgos Each amount of time to look back, in seconds, at which point to return an observation
    /// @param tick The current tick
    /// @param index The index of the observation that was most recently written to the observations array
    /// @param liquidity The current in-range pool liquidity
    /// @param cardinality The number of populated elements in the oracle array
    /// @return tickCumulatives The tick * time elapsed since the pool was first initialized, as of each `secondsAgo`
    /// @return secondsPerLiquidityCumulativeX128s The cumulative seconds / max(1, liquidity) since the pool was first initialized, as of each `secondsAgo`
    function observe(
        Observation[65535] storage self,
        uint32 time,
        uint32[] memory secondsAgos,
        int24 tick,
        uint16 index,
        uint128 liquidity,
        uint16 cardinality
    ) internal view returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s) {
        require(cardinality > 0, 'I');
        tickCumulatives = new int56[](secondsAgos.length);
        secondsPerLiquidityCumulativeX128s = new uint160[](secondsAgos.length);
        for (uint256 i = 0; i < secondsAgos.length; i++) {
            (tickCumulatives[i], secondsPerLiquidityCumulativeX128s[i]) = observeSingle(
                self,
                time,
                secondsAgos[i],
                tick,
                index,
                liquidity,
                cardinality
            );
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.0;
/// @title Contains 512-bit math functions
/// @notice Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision
/// @dev Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits
library FullMath {
    /// @notice Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
    /// @param a The multiplicand
    /// @param b The multiplier
    /// @param denominator The divisor
    /// @return result The 256-bit result
    /// @dev Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv
    function mulDiv(
        uint256 a,
        uint256 b,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        // 512-bit multiply [prod1 prod0] = a * b
        // Compute the product mod 2**256 and mod 2**256 - 1
        // then use the Chinese Remainder Theorem to reconstruct
        // the 512 bit result. The result is stored in two 256
        // variables such that product = prod1 * 2**256 + prod0
        uint256 prod0; // Least significant 256 bits of the product
        uint256 prod1; // Most significant 256 bits of the product
        assembly {
            let mm := mulmod(a, b, not(0))
            prod0 := mul(a, b)
            prod1 := sub(sub(mm, prod0), lt(mm, prod0))
        }
        // Handle non-overflow cases, 256 by 256 division
        if (prod1 == 0) {
            require(denominator > 0);
            assembly {
                result := div(prod0, denominator)
            }
            return result;
        }
        // Make sure the result is less than 2**256.
        // Also prevents denominator == 0
        require(denominator > prod1);
        ///////////////////////////////////////////////
        // 512 by 256 division.
        ///////////////////////////////////////////////
        // Make division exact by subtracting the remainder from [prod1 prod0]
        // Compute remainder using mulmod
        uint256 remainder;
        assembly {
            remainder := mulmod(a, b, denominator)
        }
        // Subtract 256 bit number from 512 bit number
        assembly {
            prod1 := sub(prod1, gt(remainder, prod0))
            prod0 := sub(prod0, remainder)
        }
        // Factor powers of two out of denominator
        // Compute largest power of two divisor of denominator.
        // Always >= 1.
        uint256 twos = -denominator & denominator;
        // Divide denominator by power of two
        assembly {
            denominator := div(denominator, twos)
        }
        // Divide [prod1 prod0] by the factors of two
        assembly {
            prod0 := div(prod0, twos)
        }
        // Shift in bits from prod1 into prod0. For this we need
        // to flip `twos` such that it is 2**256 / twos.
        // If twos is zero, then it becomes one
        assembly {
            twos := add(div(sub(0, twos), twos), 1)
        }
        prod0 |= prod1 * twos;
        // Invert denominator mod 2**256
        // Now that denominator is an odd number, it has an inverse
        // modulo 2**256 such that denominator * inv = 1 mod 2**256.
        // Compute the inverse by starting with a seed that is correct
        // correct for four bits. That is, denominator * inv = 1 mod 2**4
        uint256 inv = (3 * denominator) ^ 2;
        // Now use Newton-Raphson iteration to improve the precision.
        // Thanks to Hensel's lifting lemma, this also works in modular
        // arithmetic, doubling the correct bits in each step.
        inv *= 2 - denominator * inv; // inverse mod 2**8
        inv *= 2 - denominator * inv; // inverse mod 2**16
        inv *= 2 - denominator * inv; // inverse mod 2**32
        inv *= 2 - denominator * inv; // inverse mod 2**64
        inv *= 2 - denominator * inv; // inverse mod 2**128
        inv *= 2 - denominator * inv; // inverse mod 2**256
        // Because the division is now exact we can divide by multiplying
        // with the modular inverse of denominator. This will give us the
        // correct result modulo 2**256. Since the precoditions guarantee
        // that the outcome is less than 2**256, this is the final result.
        // We don't need to compute the high bits of the result and prod1
        // is no longer required.
        result = prod0 * inv;
        return result;
    }
    /// @notice Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
    /// @param a The multiplicand
    /// @param b The multiplier
    /// @param denominator The divisor
    /// @return result The 256-bit result
    function mulDivRoundingUp(
        uint256 a,
        uint256 b,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        result = mulDiv(a, b, denominator);
        if (mulmod(a, b, denominator) > 0) {
            require(result < type(uint256).max);
            result++;
        }
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.4.0;
/// @title FixedPoint128
/// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
library FixedPoint128 {
    uint256 internal constant Q128 = 0x100000000000000000000000000000000;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.6.0;
import '../interfaces/IERC20Minimal.sol';
/// @title TransferHelper
/// @notice Contains helper methods for interacting with ERC20 tokens that do not consistently return true/false
library TransferHelper {
    /// @notice Transfers tokens from msg.sender to a recipient
    /// @dev Calls transfer on token contract, errors with TF if transfer fails
    /// @param token The contract address of the token which will be transferred
    /// @param to The recipient of the transfer
    /// @param value The value of the transfer
    function safeTransfer(
        address token,
        address to,
        uint256 value
    ) internal {
        (bool success, bytes memory data) =
            token.call(abi.encodeWithSelector(IERC20Minimal.transfer.selector, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TF');
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Math library for computing sqrt prices from ticks and vice versa
/// @notice Computes sqrt price for ticks of size 1.0001, i.e. sqrt(1.0001^tick) as fixed point Q64.96 numbers. Supports
/// prices between 2**-128 and 2**128
library TickMath {
    /// @dev The minimum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**-128
    int24 internal constant MIN_TICK = -887272;
    /// @dev The maximum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**128
    int24 internal constant MAX_TICK = -MIN_TICK;
    /// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
    uint160 internal constant MIN_SQRT_RATIO = 4295128739;
    /// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
    uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;
    /// @notice Calculates sqrt(1.0001^tick) * 2^96
    /// @dev Throws if |tick| > max tick
    /// @param tick The input tick for the above formula
    /// @return sqrtPriceX96 A Fixed point Q64.96 number representing the sqrt of the ratio of the two assets (token1/token0)
    /// at the given tick
    function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 sqrtPriceX96) {
        uint256 absTick = tick < 0 ? uint256(-int256(tick)) : uint256(int256(tick));
        require(absTick <= uint256(MAX_TICK), 'T');
        uint256 ratio = absTick & 0x1 != 0 ? 0xfffcb933bd6fad37aa2d162d1a594001 : 0x100000000000000000000000000000000;
        if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
        if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
        if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
        if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
        if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
        if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
        if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
        if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
        if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
        if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
        if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
        if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
        if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
        if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
        if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
        if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
        if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
        if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
        if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;
        if (tick > 0) ratio = type(uint256).max / ratio;
        // this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
        // we then downcast because we know the result always fits within 160 bits due to our tick input constraint
        // we round up in the division so getTickAtSqrtRatio of the output price is always consistent
        sqrtPriceX96 = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
    }
    /// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
    /// @dev Throws in case sqrtPriceX96 < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
    /// ever return.
    /// @param sqrtPriceX96 The sqrt ratio for which to compute the tick as a Q64.96
    /// @return tick The greatest tick for which the ratio is less than or equal to the input ratio
    function getTickAtSqrtRatio(uint160 sqrtPriceX96) internal pure returns (int24 tick) {
        // second inequality must be < because the price can never reach the price at the max tick
        require(sqrtPriceX96 >= MIN_SQRT_RATIO && sqrtPriceX96 < MAX_SQRT_RATIO, 'R');
        uint256 ratio = uint256(sqrtPriceX96) << 32;
        uint256 r = ratio;
        uint256 msb = 0;
        assembly {
            let f := shl(7, gt(r, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(6, gt(r, 0xFFFFFFFFFFFFFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(5, gt(r, 0xFFFFFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(4, gt(r, 0xFFFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(3, gt(r, 0xFF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(2, gt(r, 0xF))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := shl(1, gt(r, 0x3))
            msb := or(msb, f)
            r := shr(f, r)
        }
        assembly {
            let f := gt(r, 0x1)
            msb := or(msb, f)
        }
        if (msb >= 128) r = ratio >> (msb - 127);
        else r = ratio << (127 - msb);
        int256 log_2 = (int256(msb) - 128) << 64;
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(63, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(62, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(61, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(60, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(59, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(58, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(57, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(56, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(55, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(54, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(53, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(52, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(51, f))
            r := shr(f, r)
        }
        assembly {
            r := shr(127, mul(r, r))
            let f := shr(128, r)
            log_2 := or(log_2, shl(50, f))
        }
        int256 log_sqrt10001 = log_2 * 255738958999603826347141; // 128.128 number
        int24 tickLow = int24((log_sqrt10001 - 3402992956809132418596140100660247210) >> 128);
        int24 tickHi = int24((log_sqrt10001 + 291339464771989622907027621153398088495) >> 128);
        tick = tickLow == tickHi ? tickLow : getSqrtRatioAtTick(tickHi) <= sqrtPriceX96 ? tickHi : tickLow;
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Math library for liquidity
library LiquidityMath {
    /// @notice Add a signed liquidity delta to liquidity and revert if it overflows or underflows
    /// @param x The liquidity before change
    /// @param y The delta by which liquidity should be changed
    /// @return z The liquidity delta
    function addDelta(uint128 x, int128 y) internal pure returns (uint128 z) {
        if (y < 0) {
            require((z = x - uint128(-y)) < x, 'LS');
        } else {
            require((z = x + uint128(y)) >= x, 'LA');
        }
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './LowGasSafeMath.sol';
import './SafeCast.sol';
import './FullMath.sol';
import './UnsafeMath.sol';
import './FixedPoint96.sol';
/// @title Functions based on Q64.96 sqrt price and liquidity
/// @notice Contains the math that uses square root of price as a Q64.96 and liquidity to compute deltas
library SqrtPriceMath {
    using LowGasSafeMath for uint256;
    using SafeCast for uint256;
    /// @notice Gets the next sqrt price given a delta of token0
    /// @dev Always rounds up, because in the exact output case (increasing price) we need to move the price at least
    /// far enough to get the desired output amount, and in the exact input case (decreasing price) we need to move the
    /// price less in order to not send too much output.
    /// The most precise formula for this is liquidity * sqrtPX96 / (liquidity +- amount * sqrtPX96),
    /// if this is impossible because of overflow, we calculate liquidity / (liquidity / sqrtPX96 +- amount).
    /// @param sqrtPX96 The starting price, i.e. before accounting for the token0 delta
    /// @param liquidity The amount of usable liquidity
    /// @param amount How much of token0 to add or remove from virtual reserves
    /// @param add Whether to add or remove the amount of token0
    /// @return The price after adding or removing amount, depending on add
    function getNextSqrtPriceFromAmount0RoundingUp(
        uint160 sqrtPX96,
        uint128 liquidity,
        uint256 amount,
        bool add
    ) internal pure returns (uint160) {
        // we short circuit amount == 0 because the result is otherwise not guaranteed to equal the input price
        if (amount == 0) return sqrtPX96;
        uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
        if (add) {
            uint256 product;
            if ((product = amount * sqrtPX96) / amount == sqrtPX96) {
                uint256 denominator = numerator1 + product;
                if (denominator >= numerator1)
                    // always fits in 160 bits
                    return uint160(FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator));
            }
            return uint160(UnsafeMath.divRoundingUp(numerator1, (numerator1 / sqrtPX96).add(amount)));
        } else {
            uint256 product;
            // if the product overflows, we know the denominator underflows
            // in addition, we must check that the denominator does not underflow
            require((product = amount * sqrtPX96) / amount == sqrtPX96 && numerator1 > product);
            uint256 denominator = numerator1 - product;
            return FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator).toUint160();
        }
    }
    /// @notice Gets the next sqrt price given a delta of token1
    /// @dev Always rounds down, because in the exact output case (decreasing price) we need to move the price at least
    /// far enough to get the desired output amount, and in the exact input case (increasing price) we need to move the
    /// price less in order to not send too much output.
    /// The formula we compute is within <1 wei of the lossless version: sqrtPX96 +- amount / liquidity
    /// @param sqrtPX96 The starting price, i.e., before accounting for the token1 delta
    /// @param liquidity The amount of usable liquidity
    /// @param amount How much of token1 to add, or remove, from virtual reserves
    /// @param add Whether to add, or remove, the amount of token1
    /// @return The price after adding or removing `amount`
    function getNextSqrtPriceFromAmount1RoundingDown(
        uint160 sqrtPX96,
        uint128 liquidity,
        uint256 amount,
        bool add
    ) internal pure returns (uint160) {
        // if we're adding (subtracting), rounding down requires rounding the quotient down (up)
        // in both cases, avoid a mulDiv for most inputs
        if (add) {
            uint256 quotient =
                (
                    amount <= type(uint160).max
                        ? (amount << FixedPoint96.RESOLUTION) / liquidity
                        : FullMath.mulDiv(amount, FixedPoint96.Q96, liquidity)
                );
            return uint256(sqrtPX96).add(quotient).toUint160();
        } else {
            uint256 quotient =
                (
                    amount <= type(uint160).max
                        ? UnsafeMath.divRoundingUp(amount << FixedPoint96.RESOLUTION, liquidity)
                        : FullMath.mulDivRoundingUp(amount, FixedPoint96.Q96, liquidity)
                );
            require(sqrtPX96 > quotient);
            // always fits 160 bits
            return uint160(sqrtPX96 - quotient);
        }
    }
    /// @notice Gets the next sqrt price given an input amount of token0 or token1
    /// @dev Throws if price or liquidity are 0, or if the next price is out of bounds
    /// @param sqrtPX96 The starting price, i.e., before accounting for the input amount
    /// @param liquidity The amount of usable liquidity
    /// @param amountIn How much of token0, or token1, is being swapped in
    /// @param zeroForOne Whether the amount in is token0 or token1
    /// @return sqrtQX96 The price after adding the input amount to token0 or token1
    function getNextSqrtPriceFromInput(
        uint160 sqrtPX96,
        uint128 liquidity,
        uint256 amountIn,
        bool zeroForOne
    ) internal pure returns (uint160 sqrtQX96) {
        require(sqrtPX96 > 0);
        require(liquidity > 0);
        // round to make sure that we don't pass the target price
        return
            zeroForOne
                ? getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountIn, true)
                : getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountIn, true);
    }
    /// @notice Gets the next sqrt price given an output amount of token0 or token1
    /// @dev Throws if price or liquidity are 0 or the next price is out of bounds
    /// @param sqrtPX96 The starting price before accounting for the output amount
    /// @param liquidity The amount of usable liquidity
    /// @param amountOut How much of token0, or token1, is being swapped out
    /// @param zeroForOne Whether the amount out is token0 or token1
    /// @return sqrtQX96 The price after removing the output amount of token0 or token1
    function getNextSqrtPriceFromOutput(
        uint160 sqrtPX96,
        uint128 liquidity,
        uint256 amountOut,
        bool zeroForOne
    ) internal pure returns (uint160 sqrtQX96) {
        require(sqrtPX96 > 0);
        require(liquidity > 0);
        // round to make sure that we pass the target price
        return
            zeroForOne
                ? getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountOut, false)
                : getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountOut, false);
    }
    /// @notice Gets the amount0 delta between two prices
    /// @dev Calculates liquidity / sqrt(lower) - liquidity / sqrt(upper),
    /// i.e. liquidity * (sqrt(upper) - sqrt(lower)) / (sqrt(upper) * sqrt(lower))
    /// @param sqrtRatioAX96 A sqrt price
    /// @param sqrtRatioBX96 Another sqrt price
    /// @param liquidity The amount of usable liquidity
    /// @param roundUp Whether to round the amount up or down
    /// @return amount0 Amount of token0 required to cover a position of size liquidity between the two passed prices
    function getAmount0Delta(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint128 liquidity,
        bool roundUp
    ) internal pure returns (uint256 amount0) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
        uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
        uint256 numerator2 = sqrtRatioBX96 - sqrtRatioAX96;
        require(sqrtRatioAX96 > 0);
        return
            roundUp
                ? UnsafeMath.divRoundingUp(
                    FullMath.mulDivRoundingUp(numerator1, numerator2, sqrtRatioBX96),
                    sqrtRatioAX96
                )
                : FullMath.mulDiv(numerator1, numerator2, sqrtRatioBX96) / sqrtRatioAX96;
    }
    /// @notice Gets the amount1 delta between two prices
    /// @dev Calculates liquidity * (sqrt(upper) - sqrt(lower))
    /// @param sqrtRatioAX96 A sqrt price
    /// @param sqrtRatioBX96 Another sqrt price
    /// @param liquidity The amount of usable liquidity
    /// @param roundUp Whether to round the amount up, or down
    /// @return amount1 Amount of token1 required to cover a position of size liquidity between the two passed prices
    function getAmount1Delta(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        uint128 liquidity,
        bool roundUp
    ) internal pure returns (uint256 amount1) {
        if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
        return
            roundUp
                ? FullMath.mulDivRoundingUp(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96)
                : FullMath.mulDiv(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96);
    }
    /// @notice Helper that gets signed token0 delta
    /// @param sqrtRatioAX96 A sqrt price
    /// @param sqrtRatioBX96 Another sqrt price
    /// @param liquidity The change in liquidity for which to compute the amount0 delta
    /// @return amount0 Amount of token0 corresponding to the passed liquidityDelta between the two prices
    function getAmount0Delta(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        int128 liquidity
    ) internal pure returns (int256 amount0) {
        return
            liquidity < 0
                ? -getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
                : getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
    }
    /// @notice Helper that gets signed token1 delta
    /// @param sqrtRatioAX96 A sqrt price
    /// @param sqrtRatioBX96 Another sqrt price
    /// @param liquidity The change in liquidity for which to compute the amount1 delta
    /// @return amount1 Amount of token1 corresponding to the passed liquidityDelta between the two prices
    function getAmount1Delta(
        uint160 sqrtRatioAX96,
        uint160 sqrtRatioBX96,
        int128 liquidity
    ) internal pure returns (int256 amount1) {
        return
            liquidity < 0
                ? -getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
                : getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './FullMath.sol';
import './SqrtPriceMath.sol';
/// @title Computes the result of a swap within ticks
/// @notice Contains methods for computing the result of a swap within a single tick price range, i.e., a single tick.
library SwapMath {
    /// @notice Computes the result of swapping some amount in, or amount out, given the parameters of the swap
    /// @dev The fee, plus the amount in, will never exceed the amount remaining if the swap's `amountSpecified` is positive
    /// @param sqrtRatioCurrentX96 The current sqrt price of the pool
    /// @param sqrtRatioTargetX96 The price that cannot be exceeded, from which the direction of the swap is inferred
    /// @param liquidity The usable liquidity
    /// @param amountRemaining How much input or output amount is remaining to be swapped in/out
    /// @param feePips The fee taken from the input amount, expressed in hundredths of a bip
    /// @return sqrtRatioNextX96 The price after swapping the amount in/out, not to exceed the price target
    /// @return amountIn The amount to be swapped in, of either token0 or token1, based on the direction of the swap
    /// @return amountOut The amount to be received, of either token0 or token1, based on the direction of the swap
    /// @return feeAmount The amount of input that will be taken as a fee
    function computeSwapStep(
        uint160 sqrtRatioCurrentX96,
        uint160 sqrtRatioTargetX96,
        uint128 liquidity,
        int256 amountRemaining,
        uint24 feePips
    )
        internal
        pure
        returns (
            uint160 sqrtRatioNextX96,
            uint256 amountIn,
            uint256 amountOut,
            uint256 feeAmount
        )
    {
        bool zeroForOne = sqrtRatioCurrentX96 >= sqrtRatioTargetX96;
        bool exactIn = amountRemaining >= 0;
        if (exactIn) {
            uint256 amountRemainingLessFee = FullMath.mulDiv(uint256(amountRemaining), 1e6 - feePips, 1e6);
            amountIn = zeroForOne
                ? SqrtPriceMath.getAmount0Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, true)
                : SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, true);
            if (amountRemainingLessFee >= amountIn) sqrtRatioNextX96 = sqrtRatioTargetX96;
            else
                sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromInput(
                    sqrtRatioCurrentX96,
                    liquidity,
                    amountRemainingLessFee,
                    zeroForOne
                );
        } else {
            amountOut = zeroForOne
                ? SqrtPriceMath.getAmount1Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, false)
                : SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, false);
            if (uint256(-amountRemaining) >= amountOut) sqrtRatioNextX96 = sqrtRatioTargetX96;
            else
                sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromOutput(
                    sqrtRatioCurrentX96,
                    liquidity,
                    uint256(-amountRemaining),
                    zeroForOne
                );
        }
        bool max = sqrtRatioTargetX96 == sqrtRatioNextX96;
        // get the input/output amounts
        if (zeroForOne) {
            amountIn = max && exactIn
                ? amountIn
                : SqrtPriceMath.getAmount0Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, true);
            amountOut = max && !exactIn
                ? amountOut
                : SqrtPriceMath.getAmount1Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, false);
        } else {
            amountIn = max && exactIn
                ? amountIn
                : SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, true);
            amountOut = max && !exactIn
                ? amountOut
                : SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, false);
        }
        // cap the output amount to not exceed the remaining output amount
        if (!exactIn && amountOut > uint256(-amountRemaining)) {
            amountOut = uint256(-amountRemaining);
        }
        if (exactIn && sqrtRatioNextX96 != sqrtRatioTargetX96) {
            // we didn't reach the target, so take the remainder of the maximum input as fee
            feeAmount = uint256(amountRemaining) - amountIn;
        } else {
            feeAmount = FullMath.mulDivRoundingUp(amountIn, feePips, 1e6 - feePips);
        }
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title An interface for a contract that is capable of deploying Uniswap V3 Pools
/// @notice A contract that constructs a pool must implement this to pass arguments to the pool
/// @dev This is used to avoid having constructor arguments in the pool contract, which results in the init code hash
/// of the pool being constant allowing the CREATE2 address of the pool to be cheaply computed on-chain
interface IUniswapV3PoolDeployer {
    /// @notice Get the parameters to be used in constructing the pool, set transiently during pool creation.
    /// @dev Called by the pool constructor to fetch the parameters of the pool
    /// Returns factory The factory address
    /// Returns token0 The first token of the pool by address sort order
    /// Returns token1 The second token of the pool by address sort order
    /// Returns fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
    /// Returns tickSpacing The minimum number of ticks between initialized ticks
    function parameters()
        external
        view
        returns (
            address factory,
            address token0,
            address token1,
            uint24 fee,
            int24 tickSpacing
        );
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title The interface for the Uniswap V3 Factory
/// @notice The Uniswap V3 Factory facilitates creation of Uniswap V3 pools and control over the protocol fees
interface IUniswapV3Factory {
    /// @notice Emitted when the owner of the factory is changed
    /// @param oldOwner The owner before the owner was changed
    /// @param newOwner The owner after the owner was changed
    event OwnerChanged(address indexed oldOwner, address indexed newOwner);
    /// @notice Emitted when a pool is created
    /// @param token0 The first token of the pool by address sort order
    /// @param token1 The second token of the pool by address sort order
    /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
    /// @param tickSpacing The minimum number of ticks between initialized ticks
    /// @param pool The address of the created pool
    event PoolCreated(
        address indexed token0,
        address indexed token1,
        uint24 indexed fee,
        int24 tickSpacing,
        address pool
    );
    /// @notice Emitted when a new fee amount is enabled for pool creation via the factory
    /// @param fee The enabled fee, denominated in hundredths of a bip
    /// @param tickSpacing The minimum number of ticks between initialized ticks for pools created with the given fee
    event FeeAmountEnabled(uint24 indexed fee, int24 indexed tickSpacing);
    /// @notice Returns the current owner of the factory
    /// @dev Can be changed by the current owner via setOwner
    /// @return The address of the factory owner
    function owner() external view returns (address);
    /// @notice Returns the tick spacing for a given fee amount, if enabled, or 0 if not enabled
    /// @dev A fee amount can never be removed, so this value should be hard coded or cached in the calling context
    /// @param fee The enabled fee, denominated in hundredths of a bip. Returns 0 in case of unenabled fee
    /// @return The tick spacing
    function feeAmountTickSpacing(uint24 fee) external view returns (int24);
    /// @notice Returns the pool address for a given pair of tokens and a fee, or address 0 if it does not exist
    /// @dev tokenA and tokenB may be passed in either token0/token1 or token1/token0 order
    /// @param tokenA The contract address of either token0 or token1
    /// @param tokenB The contract address of the other token
    /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
    /// @return pool The pool address
    function getPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) external view returns (address pool);
    /// @notice Creates a pool for the given two tokens and fee
    /// @param tokenA One of the two tokens in the desired pool
    /// @param tokenB The other of the two tokens in the desired pool
    /// @param fee The desired fee for the pool
    /// @dev tokenA and tokenB may be passed in either order: token0/token1 or token1/token0. tickSpacing is retrieved
    /// from the fee. The call will revert if the pool already exists, the fee is invalid, or the token arguments
    /// are invalid.
    /// @return pool The address of the newly created pool
    function createPool(
        address tokenA,
        address tokenB,
        uint24 fee
    ) external returns (address pool);
    /// @notice Updates the owner of the factory
    /// @dev Must be called by the current owner
    /// @param _owner The new owner of the factory
    function setOwner(address _owner) external;
    /// @notice Enables a fee amount with the given tickSpacing
    /// @dev Fee amounts may never be removed once enabled
    /// @param fee The fee amount to enable, denominated in hundredths of a bip (i.e. 1e-6)
    /// @param tickSpacing The spacing between ticks to be enforced for all pools created with the given fee amount
    function enableFeeAmount(uint24 fee, int24 tickSpacing) external;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Minimal ERC20 interface for Uniswap
/// @notice Contains a subset of the full ERC20 interface that is used in Uniswap V3
interface IERC20Minimal {
    /// @notice Returns the balance of a token
    /// @param account The account for which to look up the number of tokens it has, i.e. its balance
    /// @return The number of tokens held by the account
    function balanceOf(address account) external view returns (uint256);
    /// @notice Transfers the amount of token from the `msg.sender` to the recipient
    /// @param recipient The account that will receive the amount transferred
    /// @param amount The number of tokens to send from the sender to the recipient
    /// @return Returns true for a successful transfer, false for an unsuccessful transfer
    function transfer(address recipient, uint256 amount) external returns (bool);
    /// @notice Returns the current allowance given to a spender by an owner
    /// @param owner The account of the token owner
    /// @param spender The account of the token spender
    /// @return The current allowance granted by `owner` to `spender`
    function allowance(address owner, address spender) external view returns (uint256);
    /// @notice Sets the allowance of a spender from the `msg.sender` to the value `amount`
    /// @param spender The account which will be allowed to spend a given amount of the owners tokens
    /// @param amount The amount of tokens allowed to be used by `spender`
    /// @return Returns true for a successful approval, false for unsuccessful
    function approve(address spender, uint256 amount) external returns (bool);
    /// @notice Transfers `amount` tokens from `sender` to `recipient` up to the allowance given to the `msg.sender`
    /// @param sender The account from which the transfer will be initiated
    /// @param recipient The recipient of the transfer
    /// @param amount The amount of the transfer
    /// @return Returns true for a successful transfer, false for unsuccessful
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);
    /// @notice Event emitted when tokens are transferred from one address to another, either via `#transfer` or `#transferFrom`.
    /// @param from The account from which the tokens were sent, i.e. the balance decreased
    /// @param to The account to which the tokens were sent, i.e. the balance increased
    /// @param value The amount of tokens that were transferred
    event Transfer(address indexed from, address indexed to, uint256 value);
    /// @notice Event emitted when the approval amount for the spender of a given owner's tokens changes.
    /// @param owner The account that approved spending of its tokens
    /// @param spender The account for which the spending allowance was modified
    /// @param value The new allowance from the owner to the spender
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Callback for IUniswapV3PoolActions#mint
/// @notice Any contract that calls IUniswapV3PoolActions#mint must implement this interface
interface IUniswapV3MintCallback {
    /// @notice Called to `msg.sender` after minting liquidity to a position from IUniswapV3Pool#mint.
    /// @dev In the implementation you must pay the pool tokens owed for the minted liquidity.
    /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
    /// @param amount0Owed The amount of token0 due to the pool for the minted liquidity
    /// @param amount1Owed The amount of token1 due to the pool for the minted liquidity
    /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#mint call
    function uniswapV3MintCallback(
        uint256 amount0Owed,
        uint256 amount1Owed,
        bytes calldata data
    ) external;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Callback for IUniswapV3PoolActions#swap
/// @notice Any contract that calls IUniswapV3PoolActions#swap must implement this interface
interface IUniswapV3SwapCallback {
    /// @notice Called to `msg.sender` after executing a swap via IUniswapV3Pool#swap.
    /// @dev In the implementation you must pay the pool tokens owed for the swap.
    /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
    /// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
    /// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
    /// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
    /// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
    /// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
    /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#swap call
    function uniswapV3SwapCallback(
        int256 amount0Delta,
        int256 amount1Delta,
        bytes calldata data
    ) external;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Callback for IUniswapV3PoolActions#flash
/// @notice Any contract that calls IUniswapV3PoolActions#flash must implement this interface
interface IUniswapV3FlashCallback {
    /// @notice Called to `msg.sender` after transferring to the recipient from IUniswapV3Pool#flash.
    /// @dev In the implementation you must repay the pool the tokens sent by flash plus the computed fee amounts.
    /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
    /// @param fee0 The fee amount in token0 due to the pool by the end of the flash
    /// @param fee1 The fee amount in token1 due to the pool by the end of the flash
    /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#flash call
    function uniswapV3FlashCallback(
        uint256 fee0,
        uint256 fee1,
        bytes calldata data
    ) external;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Pool state that never changes
/// @notice These parameters are fixed for a pool forever, i.e., the methods will always return the same values
interface IUniswapV3PoolImmutables {
    /// @notice The contract that deployed the pool, which must adhere to the IUniswapV3Factory interface
    /// @return The contract address
    function factory() external view returns (address);
    /// @notice The first of the two tokens of the pool, sorted by address
    /// @return The token contract address
    function token0() external view returns (address);
    /// @notice The second of the two tokens of the pool, sorted by address
    /// @return The token contract address
    function token1() external view returns (address);
    /// @notice The pool's fee in hundredths of a bip, i.e. 1e-6
    /// @return The fee
    function fee() external view returns (uint24);
    /// @notice The pool tick spacing
    /// @dev Ticks can only be used at multiples of this value, minimum of 1 and always positive
    /// e.g.: a tickSpacing of 3 means ticks can be initialized every 3rd tick, i.e., ..., -6, -3, 0, 3, 6, ...
    /// This value is an int24 to avoid casting even though it is always positive.
    /// @return The tick spacing
    function tickSpacing() external view returns (int24);
    /// @notice The maximum amount of position liquidity that can use any tick in the range
    /// @dev This parameter is enforced per tick to prevent liquidity from overflowing a uint128 at any point, and
    /// also prevents out-of-range liquidity from being used to prevent adding in-range liquidity to a pool
    /// @return The max amount of liquidity per tick
    function maxLiquidityPerTick() external view returns (uint128);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Pool state that can change
/// @notice These methods compose the pool's state, and can change with any frequency including multiple times
/// per transaction
interface IUniswapV3PoolState {
    /// @notice The 0th storage slot in the pool stores many values, and is exposed as a single method to save gas
    /// when accessed externally.
    /// @return sqrtPriceX96 The current price of the pool as a sqrt(token1/token0) Q64.96 value
    /// tick The current tick of the pool, i.e. according to the last tick transition that was run.
    /// This value may not always be equal to SqrtTickMath.getTickAtSqrtRatio(sqrtPriceX96) if the price is on a tick
    /// boundary.
    /// observationIndex The index of the last oracle observation that was written,
    /// observationCardinality The current maximum number of observations stored in the pool,
    /// observationCardinalityNext The next maximum number of observations, to be updated when the observation.
    /// feeProtocol The protocol fee for both tokens of the pool.
    /// Encoded as two 4 bit values, where the protocol fee of token1 is shifted 4 bits and the protocol fee of token0
    /// is the lower 4 bits. Used as the denominator of a fraction of the swap fee, e.g. 4 means 1/4th of the swap fee.
    /// unlocked Whether the pool is currently locked to reentrancy
    function slot0()
        external
        view
        returns (
            uint160 sqrtPriceX96,
            int24 tick,
            uint16 observationIndex,
            uint16 observationCardinality,
            uint16 observationCardinalityNext,
            uint8 feeProtocol,
            bool unlocked
        );
    /// @notice The fee growth as a Q128.128 fees of token0 collected per unit of liquidity for the entire life of the pool
    /// @dev This value can overflow the uint256
    function feeGrowthGlobal0X128() external view returns (uint256);
    /// @notice The fee growth as a Q128.128 fees of token1 collected per unit of liquidity for the entire life of the pool
    /// @dev This value can overflow the uint256
    function feeGrowthGlobal1X128() external view returns (uint256);
    /// @notice The amounts of token0 and token1 that are owed to the protocol
    /// @dev Protocol fees will never exceed uint128 max in either token
    function protocolFees() external view returns (uint128 token0, uint128 token1);
    /// @notice The currently in range liquidity available to the pool
    /// @dev This value has no relationship to the total liquidity across all ticks
    function liquidity() external view returns (uint128);
    /// @notice Look up information about a specific tick in the pool
    /// @param tick The tick to look up
    /// @return liquidityGross the total amount of position liquidity that uses the pool either as tick lower or
    /// tick upper,
    /// liquidityNet how much liquidity changes when the pool price crosses the tick,
    /// feeGrowthOutside0X128 the fee growth on the other side of the tick from the current tick in token0,
    /// feeGrowthOutside1X128 the fee growth on the other side of the tick from the current tick in token1,
    /// tickCumulativeOutside the cumulative tick value on the other side of the tick from the current tick
    /// secondsPerLiquidityOutsideX128 the seconds spent per liquidity on the other side of the tick from the current tick,
    /// secondsOutside the seconds spent on the other side of the tick from the current tick,
    /// initialized Set to true if the tick is initialized, i.e. liquidityGross is greater than 0, otherwise equal to false.
    /// Outside values can only be used if the tick is initialized, i.e. if liquidityGross is greater than 0.
    /// In addition, these values are only relative and must be used only in comparison to previous snapshots for
    /// a specific position.
    function ticks(int24 tick)
        external
        view
        returns (
            uint128 liquidityGross,
            int128 liquidityNet,
            uint256 feeGrowthOutside0X128,
            uint256 feeGrowthOutside1X128,
            int56 tickCumulativeOutside,
            uint160 secondsPerLiquidityOutsideX128,
            uint32 secondsOutside,
            bool initialized
        );
    /// @notice Returns 256 packed tick initialized boolean values. See TickBitmap for more information
    function tickBitmap(int16 wordPosition) external view returns (uint256);
    /// @notice Returns the information about a position by the position's key
    /// @param key The position's key is a hash of a preimage composed by the owner, tickLower and tickUpper
    /// @return _liquidity The amount of liquidity in the position,
    /// Returns feeGrowthInside0LastX128 fee growth of token0 inside the tick range as of the last mint/burn/poke,
    /// Returns feeGrowthInside1LastX128 fee growth of token1 inside the tick range as of the last mint/burn/poke,
    /// Returns tokensOwed0 the computed amount of token0 owed to the position as of the last mint/burn/poke,
    /// Returns tokensOwed1 the computed amount of token1 owed to the position as of the last mint/burn/poke
    function positions(bytes32 key)
        external
        view
        returns (
            uint128 _liquidity,
            uint256 feeGrowthInside0LastX128,
            uint256 feeGrowthInside1LastX128,
            uint128 tokensOwed0,
            uint128 tokensOwed1
        );
    /// @notice Returns data about a specific observation index
    /// @param index The element of the observations array to fetch
    /// @dev You most likely want to use #observe() instead of this method to get an observation as of some amount of time
    /// ago, rather than at a specific index in the array.
    /// @return blockTimestamp The timestamp of the observation,
    /// Returns tickCumulative the tick multiplied by seconds elapsed for the life of the pool as of the observation timestamp,
    /// Returns secondsPerLiquidityCumulativeX128 the seconds per in range liquidity for the life of the pool as of the observation timestamp,
    /// Returns initialized whether the observation has been initialized and the values are safe to use
    function observations(uint256 index)
        external
        view
        returns (
            uint32 blockTimestamp,
            int56 tickCumulative,
            uint160 secondsPerLiquidityCumulativeX128,
            bool initialized
        );
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Pool state that is not stored
/// @notice Contains view functions to provide information about the pool that is computed rather than stored on the
/// blockchain. The functions here may have variable gas costs.
interface IUniswapV3PoolDerivedState {
    /// @notice Returns the cumulative tick and liquidity as of each timestamp `secondsAgo` from the current block timestamp
    /// @dev To get a time weighted average tick or liquidity-in-range, you must call this with two values, one representing
    /// the beginning of the period and another for the end of the period. E.g., to get the last hour time-weighted average tick,
    /// you must call it with secondsAgos = [3600, 0].
    /// @dev The time weighted average tick represents the geometric time weighted average price of the pool, in
    /// log base sqrt(1.0001) of token1 / token0. The TickMath library can be used to go from a tick value to a ratio.
    /// @param secondsAgos From how long ago each cumulative tick and liquidity value should be returned
    /// @return tickCumulatives Cumulative tick values as of each `secondsAgos` from the current block timestamp
    /// @return secondsPerLiquidityCumulativeX128s Cumulative seconds per liquidity-in-range value as of each `secondsAgos` from the current block
    /// timestamp
    function observe(uint32[] calldata secondsAgos)
        external
        view
        returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s);
    /// @notice Returns a snapshot of the tick cumulative, seconds per liquidity and seconds inside a tick range
    /// @dev Snapshots must only be compared to other snapshots, taken over a period for which a position existed.
    /// I.e., snapshots cannot be compared if a position is not held for the entire period between when the first
    /// snapshot is taken and the second snapshot is taken.
    /// @param tickLower The lower tick of the range
    /// @param tickUpper The upper tick of the range
    /// @return tickCumulativeInside The snapshot of the tick accumulator for the range
    /// @return secondsPerLiquidityInsideX128 The snapshot of seconds per liquidity for the range
    /// @return secondsInside The snapshot of seconds per liquidity for the range
    function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
        external
        view
        returns (
            int56 tickCumulativeInside,
            uint160 secondsPerLiquidityInsideX128,
            uint32 secondsInside
        );
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Permissionless pool actions
/// @notice Contains pool methods that can be called by anyone
interface IUniswapV3PoolActions {
    /// @notice Sets the initial price for the pool
    /// @dev Price is represented as a sqrt(amountToken1/amountToken0) Q64.96 value
    /// @param sqrtPriceX96 the initial sqrt price of the pool as a Q64.96
    function initialize(uint160 sqrtPriceX96) external;
    /// @notice Adds liquidity for the given recipient/tickLower/tickUpper position
    /// @dev The caller of this method receives a callback in the form of IUniswapV3MintCallback#uniswapV3MintCallback
    /// in which they must pay any token0 or token1 owed for the liquidity. The amount of token0/token1 due depends
    /// on tickLower, tickUpper, the amount of liquidity, and the current price.
    /// @param recipient The address for which the liquidity will be created
    /// @param tickLower The lower tick of the position in which to add liquidity
    /// @param tickUpper The upper tick of the position in which to add liquidity
    /// @param amount The amount of liquidity to mint
    /// @param data Any data that should be passed through to the callback
    /// @return amount0 The amount of token0 that was paid to mint the given amount of liquidity. Matches the value in the callback
    /// @return amount1 The amount of token1 that was paid to mint the given amount of liquidity. Matches the value in the callback
    function mint(
        address recipient,
        int24 tickLower,
        int24 tickUpper,
        uint128 amount,
        bytes calldata data
    ) external returns (uint256 amount0, uint256 amount1);
    /// @notice Collects tokens owed to a position
    /// @dev Does not recompute fees earned, which must be done either via mint or burn of any amount of liquidity.
    /// Collect must be called by the position owner. To withdraw only token0 or only token1, amount0Requested or
    /// amount1Requested may be set to zero. To withdraw all tokens owed, caller may pass any value greater than the
    /// actual tokens owed, e.g. type(uint128).max. Tokens owed may be from accumulated swap fees or burned liquidity.
    /// @param recipient The address which should receive the fees collected
    /// @param tickLower The lower tick of the position for which to collect fees
    /// @param tickUpper The upper tick of the position for which to collect fees
    /// @param amount0Requested How much token0 should be withdrawn from the fees owed
    /// @param amount1Requested How much token1 should be withdrawn from the fees owed
    /// @return amount0 The amount of fees collected in token0
    /// @return amount1 The amount of fees collected in token1
    function collect(
        address recipient,
        int24 tickLower,
        int24 tickUpper,
        uint128 amount0Requested,
        uint128 amount1Requested
    ) external returns (uint128 amount0, uint128 amount1);
    /// @notice Burn liquidity from the sender and account tokens owed for the liquidity to the position
    /// @dev Can be used to trigger a recalculation of fees owed to a position by calling with an amount of 0
    /// @dev Fees must be collected separately via a call to #collect
    /// @param tickLower The lower tick of the position for which to burn liquidity
    /// @param tickUpper The upper tick of the position for which to burn liquidity
    /// @param amount How much liquidity to burn
    /// @return amount0 The amount of token0 sent to the recipient
    /// @return amount1 The amount of token1 sent to the recipient
    function burn(
        int24 tickLower,
        int24 tickUpper,
        uint128 amount
    ) external returns (uint256 amount0, uint256 amount1);
    /// @notice Swap token0 for token1, or token1 for token0
    /// @dev The caller of this method receives a callback in the form of IUniswapV3SwapCallback#uniswapV3SwapCallback
    /// @param recipient The address to receive the output of the swap
    /// @param zeroForOne The direction of the swap, true for token0 to token1, false for token1 to token0
    /// @param amountSpecified The amount of the swap, which implicitly configures the swap as exact input (positive), or exact output (negative)
    /// @param sqrtPriceLimitX96 The Q64.96 sqrt price limit. If zero for one, the price cannot be less than this
    /// value after the swap. If one for zero, the price cannot be greater than this value after the swap
    /// @param data Any data to be passed through to the callback
    /// @return amount0 The delta of the balance of token0 of the pool, exact when negative, minimum when positive
    /// @return amount1 The delta of the balance of token1 of the pool, exact when negative, minimum when positive
    function swap(
        address recipient,
        bool zeroForOne,
        int256 amountSpecified,
        uint160 sqrtPriceLimitX96,
        bytes calldata data
    ) external returns (int256 amount0, int256 amount1);
    /// @notice Receive token0 and/or token1 and pay it back, plus a fee, in the callback
    /// @dev The caller of this method receives a callback in the form of IUniswapV3FlashCallback#uniswapV3FlashCallback
    /// @dev Can be used to donate underlying tokens pro-rata to currently in-range liquidity providers by calling
    /// with 0 amount{0,1} and sending the donation amount(s) from the callback
    /// @param recipient The address which will receive the token0 and token1 amounts
    /// @param amount0 The amount of token0 to send
    /// @param amount1 The amount of token1 to send
    /// @param data Any data to be passed through to the callback
    function flash(
        address recipient,
        uint256 amount0,
        uint256 amount1,
        bytes calldata data
    ) external;
    /// @notice Increase the maximum number of price and liquidity observations that this pool will store
    /// @dev This method is no-op if the pool already has an observationCardinalityNext greater than or equal to
    /// the input observationCardinalityNext.
    /// @param observationCardinalityNext The desired minimum number of observations for the pool to store
    function increaseObservationCardinalityNext(uint16 observationCardinalityNext) external;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Permissioned pool actions
/// @notice Contains pool methods that may only be called by the factory owner
interface IUniswapV3PoolOwnerActions {
    /// @notice Set the denominator of the protocol's % share of the fees
    /// @param feeProtocol0 new protocol fee for token0 of the pool
    /// @param feeProtocol1 new protocol fee for token1 of the pool
    function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external;
    /// @notice Collect the protocol fee accrued to the pool
    /// @param recipient The address to which collected protocol fees should be sent
    /// @param amount0Requested The maximum amount of token0 to send, can be 0 to collect fees in only token1
    /// @param amount1Requested The maximum amount of token1 to send, can be 0 to collect fees in only token0
    /// @return amount0 The protocol fee collected in token0
    /// @return amount1 The protocol fee collected in token1
    function collectProtocol(
        address recipient,
        uint128 amount0Requested,
        uint128 amount1Requested
    ) external returns (uint128 amount0, uint128 amount1);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Events emitted by a pool
/// @notice Contains all events emitted by the pool
interface IUniswapV3PoolEvents {
    /// @notice Emitted exactly once by a pool when #initialize is first called on the pool
    /// @dev Mint/Burn/Swap cannot be emitted by the pool before Initialize
    /// @param sqrtPriceX96 The initial sqrt price of the pool, as a Q64.96
    /// @param tick The initial tick of the pool, i.e. log base 1.0001 of the starting price of the pool
    event Initialize(uint160 sqrtPriceX96, int24 tick);
    /// @notice Emitted when liquidity is minted for a given position
    /// @param sender The address that minted the liquidity
    /// @param owner The owner of the position and recipient of any minted liquidity
    /// @param tickLower The lower tick of the position
    /// @param tickUpper The upper tick of the position
    /// @param amount The amount of liquidity minted to the position range
    /// @param amount0 How much token0 was required for the minted liquidity
    /// @param amount1 How much token1 was required for the minted liquidity
    event Mint(
        address sender,
        address indexed owner,
        int24 indexed tickLower,
        int24 indexed tickUpper,
        uint128 amount,
        uint256 amount0,
        uint256 amount1
    );
    /// @notice Emitted when fees are collected by the owner of a position
    /// @dev Collect events may be emitted with zero amount0 and amount1 when the caller chooses not to collect fees
    /// @param owner The owner of the position for which fees are collected
    /// @param tickLower The lower tick of the position
    /// @param tickUpper The upper tick of the position
    /// @param amount0 The amount of token0 fees collected
    /// @param amount1 The amount of token1 fees collected
    event Collect(
        address indexed owner,
        address recipient,
        int24 indexed tickLower,
        int24 indexed tickUpper,
        uint128 amount0,
        uint128 amount1
    );
    /// @notice Emitted when a position's liquidity is removed
    /// @dev Does not withdraw any fees earned by the liquidity position, which must be withdrawn via #collect
    /// @param owner The owner of the position for which liquidity is removed
    /// @param tickLower The lower tick of the position
    /// @param tickUpper The upper tick of the position
    /// @param amount The amount of liquidity to remove
    /// @param amount0 The amount of token0 withdrawn
    /// @param amount1 The amount of token1 withdrawn
    event Burn(
        address indexed owner,
        int24 indexed tickLower,
        int24 indexed tickUpper,
        uint128 amount,
        uint256 amount0,
        uint256 amount1
    );
    /// @notice Emitted by the pool for any swaps between token0 and token1
    /// @param sender The address that initiated the swap call, and that received the callback
    /// @param recipient The address that received the output of the swap
    /// @param amount0 The delta of the token0 balance of the pool
    /// @param amount1 The delta of the token1 balance of the pool
    /// @param sqrtPriceX96 The sqrt(price) of the pool after the swap, as a Q64.96
    /// @param liquidity The liquidity of the pool after the swap
    /// @param tick The log base 1.0001 of price of the pool after the swap
    event Swap(
        address indexed sender,
        address indexed recipient,
        int256 amount0,
        int256 amount1,
        uint160 sqrtPriceX96,
        uint128 liquidity,
        int24 tick
    );
    /// @notice Emitted by the pool for any flashes of token0/token1
    /// @param sender The address that initiated the swap call, and that received the callback
    /// @param recipient The address that received the tokens from flash
    /// @param amount0 The amount of token0 that was flashed
    /// @param amount1 The amount of token1 that was flashed
    /// @param paid0 The amount of token0 paid for the flash, which can exceed the amount0 plus the fee
    /// @param paid1 The amount of token1 paid for the flash, which can exceed the amount1 plus the fee
    event Flash(
        address indexed sender,
        address indexed recipient,
        uint256 amount0,
        uint256 amount1,
        uint256 paid0,
        uint256 paid1
    );
    /// @notice Emitted by the pool for increases to the number of observations that can be stored
    /// @dev observationCardinalityNext is not the observation cardinality until an observation is written at the index
    /// just before a mint/swap/burn.
    /// @param observationCardinalityNextOld The previous value of the next observation cardinality
    /// @param observationCardinalityNextNew The updated value of the next observation cardinality
    event IncreaseObservationCardinalityNext(
        uint16 observationCardinalityNextOld,
        uint16 observationCardinalityNextNew
    );
    /// @notice Emitted when the protocol fee is changed by the pool
    /// @param feeProtocol0Old The previous value of the token0 protocol fee
    /// @param feeProtocol1Old The previous value of the token1 protocol fee
    /// @param feeProtocol0New The updated value of the token0 protocol fee
    /// @param feeProtocol1New The updated value of the token1 protocol fee
    event SetFeeProtocol(uint8 feeProtocol0Old, uint8 feeProtocol1Old, uint8 feeProtocol0New, uint8 feeProtocol1New);
    /// @notice Emitted when the collected protocol fees are withdrawn by the factory owner
    /// @param sender The address that collects the protocol fees
    /// @param recipient The address that receives the collected protocol fees
    /// @param amount0 The amount of token0 protocol fees that is withdrawn
    /// @param amount0 The amount of token1 protocol fees that is withdrawn
    event CollectProtocol(address indexed sender, address indexed recipient, uint128 amount0, uint128 amount1);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title BitMath
/// @dev This library provides functionality for computing bit properties of an unsigned integer
library BitMath {
    /// @notice Returns the index of the most significant bit of the number,
    ///     where the least significant bit is at index 0 and the most significant bit is at index 255
    /// @dev The function satisfies the property:
    ///     x >= 2**mostSignificantBit(x) and x < 2**(mostSignificantBit(x)+1)
    /// @param x the value for which to compute the most significant bit, must be greater than 0
    /// @return r the index of the most significant bit
    function mostSignificantBit(uint256 x) internal pure returns (uint8 r) {
        require(x > 0);
        if (x >= 0x100000000000000000000000000000000) {
            x >>= 128;
            r += 128;
        }
        if (x >= 0x10000000000000000) {
            x >>= 64;
            r += 64;
        }
        if (x >= 0x100000000) {
            x >>= 32;
            r += 32;
        }
        if (x >= 0x10000) {
            x >>= 16;
            r += 16;
        }
        if (x >= 0x100) {
            x >>= 8;
            r += 8;
        }
        if (x >= 0x10) {
            x >>= 4;
            r += 4;
        }
        if (x >= 0x4) {
            x >>= 2;
            r += 2;
        }
        if (x >= 0x2) r += 1;
    }
    /// @notice Returns the index of the least significant bit of the number,
    ///     where the least significant bit is at index 0 and the most significant bit is at index 255
    /// @dev The function satisfies the property:
    ///     (x & 2**leastSignificantBit(x)) != 0 and (x & (2**(leastSignificantBit(x)) - 1)) == 0)
    /// @param x the value for which to compute the least significant bit, must be greater than 0
    /// @return r the index of the least significant bit
    function leastSignificantBit(uint256 x) internal pure returns (uint8 r) {
        require(x > 0);
        r = 255;
        if (x & type(uint128).max > 0) {
            r -= 128;
        } else {
            x >>= 128;
        }
        if (x & type(uint64).max > 0) {
            r -= 64;
        } else {
            x >>= 64;
        }
        if (x & type(uint32).max > 0) {
            r -= 32;
        } else {
            x >>= 32;
        }
        if (x & type(uint16).max > 0) {
            r -= 16;
        } else {
            x >>= 16;
        }
        if (x & type(uint8).max > 0) {
            r -= 8;
        } else {
            x >>= 8;
        }
        if (x & 0xf > 0) {
            r -= 4;
        } else {
            x >>= 4;
        }
        if (x & 0x3 > 0) {
            r -= 2;
        } else {
            x >>= 2;
        }
        if (x & 0x1 > 0) r -= 1;
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Math functions that do not check inputs or outputs
/// @notice Contains methods that perform common math functions but do not do any overflow or underflow checks
library UnsafeMath {
    /// @notice Returns ceil(x / y)
    /// @dev division by 0 has unspecified behavior, and must be checked externally
    /// @param x The dividend
    /// @param y The divisor
    /// @return z The quotient, ceil(x / y)
    function divRoundingUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
        assembly {
            z := add(div(x, y), gt(mod(x, y), 0))
        }
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.4.0;
/// @title FixedPoint96
/// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
/// @dev Used in SqrtPriceMath.sol
library FixedPoint96 {
    uint8 internal constant RESOLUTION = 96;
    uint256 internal constant Q96 = 0x1000000000000000000000000;
}

pragma solidity ^0.4.17;

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

    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;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        assert(b <= a);
        return a - b;
    }

    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;

    /**
      * @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 {
        if (newOwner != address(0)) {
            owner = newOwner;
        }
    }

}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20Basic {
    uint public _totalSupply;
    function totalSupply() public constant returns (uint);
    function balanceOf(address who) public constant returns (uint);
    function transfer(address to, uint value) public;
    event Transfer(address indexed from, address indexed to, uint value);
}

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

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

    mapping(address => uint) public balances;

    // additional variables for use if transaction fees ever became necessary
    uint public basisPointsRate = 0;
    uint public maximumFee = 0;

    /**
    * @dev Fix for the ERC20 short address attack.
    */
    modifier onlyPayloadSize(uint size) {
        require(!(msg.data.length < size + 4));
        _;
    }

    /**
    * @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, uint _value) public onlyPayloadSize(2 * 32) {
        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        uint sendAmount = _value.sub(fee);
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(msg.sender, owner, fee);
        }
        Transfer(msg.sender, _to, sendAmount);
    }

    /**
    * @dev Gets the balance of the specified address.
    * @param _owner The address to query the the balance of.
    * @return An uint representing the amount owned by the passed address.
    */
    function balanceOf(address _owner) public constant returns (uint 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 oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is BasicToken, ERC20 {

    mapping (address => mapping (address => uint)) public allowed;

    uint public constant MAX_UINT = 2**256 - 1;

    /**
    * @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 uint the amount of tokens to be transferred
    */
    function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
        var _allowance = allowed[_from][msg.sender];

        // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
        // if (_value > _allowance) throw;

        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        if (_allowance < MAX_UINT) {
            allowed[_from][msg.sender] = _allowance.sub(_value);
        }
        uint sendAmount = _value.sub(fee);
        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(_from, owner, fee);
        }
        Transfer(_from, _to, sendAmount);
    }

    /**
    * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
    * @param _spender The address which will spend the funds.
    * @param _value The amount of tokens to be spent.
    */
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {

        // To change the approve amount you first have to reduce the addresses`
        //  allowance to zero by calling `approve(_spender, 0)` if it is not
        //  already 0 to mitigate the race condition described here:
        //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
        require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));

        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
    }

    /**
    * @dev Function to check the amount of tokens than 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 uint specifying the amount of tokens still available for the spender.
    */
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        return allowed[_owner][_spender];
    }

}


/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyOwner whenPaused public {
    paused = false;
    Unpause();
  }
}

contract BlackList is Ownable, BasicToken {

    /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
    function getBlackListStatus(address _maker) external constant returns (bool) {
        return isBlackListed[_maker];
    }

    function getOwner() external constant returns (address) {
        return owner;
    }

    mapping (address => bool) public isBlackListed;
    
    function addBlackList (address _evilUser) public onlyOwner {
        isBlackListed[_evilUser] = true;
        AddedBlackList(_evilUser);
    }

    function removeBlackList (address _clearedUser) public onlyOwner {
        isBlackListed[_clearedUser] = false;
        RemovedBlackList(_clearedUser);
    }

    function destroyBlackFunds (address _blackListedUser) public onlyOwner {
        require(isBlackListed[_blackListedUser]);
        uint dirtyFunds = balanceOf(_blackListedUser);
        balances[_blackListedUser] = 0;
        _totalSupply -= dirtyFunds;
        DestroyedBlackFunds(_blackListedUser, dirtyFunds);
    }

    event DestroyedBlackFunds(address _blackListedUser, uint _balance);

    event AddedBlackList(address _user);

    event RemovedBlackList(address _user);

}

contract UpgradedStandardToken is StandardToken{
    // those methods are called by the legacy contract
    // and they must ensure msg.sender to be the contract address
    function transferByLegacy(address from, address to, uint value) public;
    function transferFromByLegacy(address sender, address from, address spender, uint value) public;
    function approveByLegacy(address from, address spender, uint value) public;
}

contract TetherToken is Pausable, StandardToken, BlackList {

    string public name;
    string public symbol;
    uint public decimals;
    address public upgradedAddress;
    bool public deprecated;

    //  The contract can be initialized with a number of tokens
    //  All the tokens are deposited to the owner address
    //
    // @param _balance Initial supply of the contract
    // @param _name Token Name
    // @param _symbol Token symbol
    // @param _decimals Token decimals
    function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
        _totalSupply = _initialSupply;
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        balances[owner] = _initialSupply;
        deprecated = false;
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transfer(address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[msg.sender]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
        } else {
            return super.transfer(_to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[_from]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
        } else {
            return super.transferFrom(_from, _to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function balanceOf(address who) public constant returns (uint) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).balanceOf(who);
        } else {
            return super.balanceOf(who);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
        } else {
            return super.approve(_spender, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        if (deprecated) {
            return StandardToken(upgradedAddress).allowance(_owner, _spender);
        } else {
            return super.allowance(_owner, _spender);
        }
    }

    // deprecate current contract in favour of a new one
    function deprecate(address _upgradedAddress) public onlyOwner {
        deprecated = true;
        upgradedAddress = _upgradedAddress;
        Deprecate(_upgradedAddress);
    }

    // deprecate current contract if favour of a new one
    function totalSupply() public constant returns (uint) {
        if (deprecated) {
            return StandardToken(upgradedAddress).totalSupply();
        } else {
            return _totalSupply;
        }
    }

    // Issue a new amount of tokens
    // these tokens are deposited into the owner address
    //
    // @param _amount Number of tokens to be issued
    function issue(uint amount) public onlyOwner {
        require(_totalSupply + amount > _totalSupply);
        require(balances[owner] + amount > balances[owner]);

        balances[owner] += amount;
        _totalSupply += amount;
        Issue(amount);
    }

    // Redeem tokens.
    // These tokens are withdrawn from the owner address
    // if the balance must be enough to cover the redeem
    // or the call will fail.
    // @param _amount Number of tokens to be issued
    function redeem(uint amount) public onlyOwner {
        require(_totalSupply >= amount);
        require(balances[owner] >= amount);

        _totalSupply -= amount;
        balances[owner] -= amount;
        Redeem(amount);
    }

    function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
        // Ensure transparency by hardcoding limit beyond which fees can never be added
        require(newBasisPoints < 20);
        require(newMaxFee < 50);

        basisPointsRate = newBasisPoints;
        maximumFee = newMaxFee.mul(10**decimals);

        Params(basisPointsRate, maximumFee);
    }

    // Called when new token are issued
    event Issue(uint amount);

    // Called when tokens are redeemed
    event Redeem(uint amount);

    // Called when contract is deprecated
    event Deprecate(address newAddress);

    // Called if contract ever adds fees
    event Params(uint feeBasisPoints, uint maxFee);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
pragma solidity ^0.8.0;
/**
 * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
 * proxy whose upgrades are fully controlled by the current implementation.
 */
interface IERC1822Proxiable {
    /**
     * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
     * address.
     *
     * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
     * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
     * function revert if invoked through a proxy.
     */
    function proxiableUUID() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (proxy/ERC1967/ERC1967Proxy.sol)
pragma solidity ^0.8.0;
import "../Proxy.sol";
import "./ERC1967Upgrade.sol";
/**
 * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
 * implementation address that can be changed. This address is stored in storage in the location specified by
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
 * implementation behind the proxy.
 */
contract ERC1967Proxy is Proxy, ERC1967Upgrade {
    /**
     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
     *
     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
     * function call, and allows initializing the storage of the proxy like a Solidity constructor.
     */
    constructor(address _logic, bytes memory _data) payable {
        _upgradeToAndCall(_logic, _data, false);
    }
    /**
     * @dev Returns the current implementation address.
     */
    function _implementation() internal view virtual override returns (address impl) {
        return ERC1967Upgrade._getImplementation();
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
pragma solidity ^0.8.2;
import "../beacon/IBeacon.sol";
import "../../interfaces/draft-IERC1822.sol";
import "../../utils/Address.sol";
import "../../utils/StorageSlot.sol";
/**
 * @dev This abstract contract provides getters and event emitting update functions for
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
 *
 * _Available since v4.1._
 *
 * @custom:oz-upgrades-unsafe-allow delegatecall
 */
abstract contract ERC1967Upgrade {
    // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
    bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
    /**
     * @dev Emitted when the implementation is upgraded.
     */
    event Upgraded(address indexed implementation);
    /**
     * @dev Returns the current implementation address.
     */
    function _getImplementation() internal view returns (address) {
        return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
    }
    /**
     * @dev Stores a new address in the EIP1967 implementation slot.
     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
        StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
    }
    /**
     * @dev Perform implementation upgrade
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }
    /**
     * @dev Perform implementation upgrade with additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCall(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        _upgradeTo(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }
    }
    /**
     * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCallUUPS(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        // Upgrades from old implementations will perform a rollback test. This test requires the new
        // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
        // this special case will break upgrade paths from old UUPS implementation to new ones.
        if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
            _setImplementation(newImplementation);
        } else {
            try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
            } catch {
                revert("ERC1967Upgrade: new implementation is not UUPS");
            }
            _upgradeToAndCall(newImplementation, data, forceCall);
        }
    }
    /**
     * @dev Storage slot with the admin of the contract.
     * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
    /**
     * @dev Emitted when the admin account has changed.
     */
    event AdminChanged(address previousAdmin, address newAdmin);
    /**
     * @dev Returns the current admin.
     */
    function _getAdmin() internal view returns (address) {
        return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
    }
    /**
     * @dev Stores a new address in the EIP1967 admin slot.
     */
    function _setAdmin(address newAdmin) private {
        require(newAdmin != address(0), "ERC1967: new admin is the zero address");
        StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
    }
    /**
     * @dev Changes the admin of the proxy.
     *
     * Emits an {AdminChanged} event.
     */
    function _changeAdmin(address newAdmin) internal {
        emit AdminChanged(_getAdmin(), newAdmin);
        _setAdmin(newAdmin);
    }
    /**
     * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
     * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
     */
    bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
    /**
     * @dev Emitted when the beacon is upgraded.
     */
    event BeaconUpgraded(address indexed beacon);
    /**
     * @dev Returns the current beacon.
     */
    function _getBeacon() internal view returns (address) {
        return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
    }
    /**
     * @dev Stores a new beacon in the EIP1967 beacon slot.
     */
    function _setBeacon(address newBeacon) private {
        require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
        require(
            Address.isContract(IBeacon(newBeacon).implementation()),
            "ERC1967: beacon implementation is not a contract"
        );
        StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
    }
    /**
     * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
     * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
     *
     * Emits a {BeaconUpgraded} event.
     */
    function _upgradeBeaconToAndCall(
        address newBeacon,
        bytes memory data,
        bool forceCall
    ) internal {
        _setBeacon(newBeacon);
        emit BeaconUpgraded(newBeacon);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (proxy/Proxy.sol)
pragma solidity ^0.8.0;
/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 *
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 *
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     *
     * This function does not return to its internal call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal virtual {
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())
            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())
            switch result
            // delegatecall returns 0 on error.
            case 0 {
                revert(0, returndatasize())
            }
            default {
                return(0, returndatasize())
            }
        }
    }
    /**
     * @dev This is a virtual function that should be overridden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal view virtual returns (address);
    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     *
     * This function does not return to its internal call site, it will return directly to the external caller.
     */
    function _fallback() internal virtual {
        _beforeFallback();
        _delegate(_implementation());
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback() external payable virtual {
        _fallback();
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive() external payable virtual {
        _fallback();
    }
    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     *
     * If overridden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
pragma solidity ^0.8.0;
/**
 * @dev This is the interface that {BeaconProxy} expects of its beacon.
 */
interface IBeacon {
    /**
     * @dev Must return an address that can be used as a delegate call target.
     *
     * {BeaconProxy} will check that this address is a contract.
     */
    function implementation() external view returns (address);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (proxy/transparent/TransparentUpgradeableProxy.sol)
pragma solidity ^0.8.0;
import "../ERC1967/ERC1967Proxy.sol";
/**
 * @dev This contract implements a proxy that is upgradeable by an admin.
 *
 * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
 * clashing], which can potentially be used in an attack, this contract uses the
 * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
 * things that go hand in hand:
 *
 * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
 * that call matches one of the admin functions exposed by the proxy itself.
 * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
 * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
 * "admin cannot fallback to proxy target".
 *
 * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
 * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
 * to sudden errors when trying to call a function from the proxy implementation.
 *
 * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
 * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
 */
contract TransparentUpgradeableProxy is ERC1967Proxy {
    /**
     * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
     * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
     */
    constructor(
        address _logic,
        address admin_,
        bytes memory _data
    ) payable ERC1967Proxy(_logic, _data) {
        _changeAdmin(admin_);
    }
    /**
     * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
     */
    modifier ifAdmin() {
        if (msg.sender == _getAdmin()) {
            _;
        } else {
            _fallback();
        }
    }
    /**
     * @dev Returns the current admin.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
     *
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
     */
    function admin() external ifAdmin returns (address admin_) {
        admin_ = _getAdmin();
    }
    /**
     * @dev Returns the current implementation.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
     *
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
     */
    function implementation() external ifAdmin returns (address implementation_) {
        implementation_ = _implementation();
    }
    /**
     * @dev Changes the admin of the proxy.
     *
     * Emits an {AdminChanged} event.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
     */
    function changeAdmin(address newAdmin) external virtual ifAdmin {
        _changeAdmin(newAdmin);
    }
    /**
     * @dev Upgrade the implementation of the proxy.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
     */
    function upgradeTo(address newImplementation) external ifAdmin {
        _upgradeToAndCall(newImplementation, bytes(""), false);
    }
    /**
     * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
     * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
     * proxied contract.
     *
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
     */
    function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
        _upgradeToAndCall(newImplementation, data, true);
    }
    /**
     * @dev Returns the current admin.
     */
    function _admin() internal view virtual returns (address) {
        return _getAdmin();
    }
    /**
     * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
     */
    function _beforeFallback() internal virtual override {
        require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
        super._beforeFallback();
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (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 functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
pragma solidity ^0.8.0;
/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC1967 implementation slot:
 * ```
 * contract ERC1967 {
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }
    struct BooleanSlot {
        bool value;
    }
    struct Bytes32Slot {
        bytes32 value;
    }
    struct Uint256Slot {
        uint256 value;
    }
    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }
}

pragma solidity 0.4.24;

// File: openzeppelin-solidity/contracts/token/ERC20/ERC20Basic.sol

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * 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);
}

// File: openzeppelin-solidity/contracts/math/SafeMath.sol

/**
 * @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 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (_a == 0) {
      return 0;
    }

    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 _a / _b;
  }

  /**
  * @dev Subtracts 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 c) {
    c = _a + _b;
    assert(c >= _a);
    return c;
  }
}

// File: openzeppelin-solidity/contracts/token/ERC20/BasicToken.sol

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

  mapping(address => uint256) internal balances;

  uint256 internal 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(_value <= balances[msg.sender]);
    require(_to != address(0));

    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit 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) {
    return balances[_owner];
  }

}

// File: openzeppelin-solidity/contracts/token/ERC20/ERC20.sol

/**
 * @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
  );
}

// File: openzeppelin-solidity/contracts/token/ERC20/StandardToken.sol

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * https://github.com/ethereum/EIPs/issues/20
 * 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(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);
    require(_to != address(0));

    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
    emit 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;
    emit 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,
    uint256 _addedValue
  )
    public
    returns (bool)
  {
    allowed[msg.sender][_spender] = (
      allowed[msg.sender][_spender].add(_addedValue));
    emit 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,
    uint256 _subtractedValue
  )
    public
    returns (bool)
  {
    uint256 oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue >= oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}

// File: openzeppelin-solidity/contracts/token/ERC20/DetailedERC20.sol

/**
 * @title DetailedERC20 token
 * @dev The decimals are only for visualization purposes.
 * All the operations are done using the smallest and indivisible token unit,
 * just as on Ethereum all the operations are done in wei.
 */
contract DetailedERC20 is ERC20 {
  string public name;
  string public symbol;
  uint8 public decimals;

  constructor(string _name, string _symbol, uint8 _decimals) public {
    name = _name;
    symbol = _symbol;
    decimals = _decimals;
  }
}

// File: openzeppelin-solidity/contracts/ownership/Ownable.sol

/**
 * @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 OwnershipRenounced(address indexed previousOwner);
  event OwnershipTransferred(
    address indexed previousOwner,
    address indexed newOwner
  );


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() 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 relinquish control of the contract.
   * @notice Renouncing to ownership will leave the contract without an owner.
   * It will not be possible to call the functions with the `onlyOwner`
   * modifier anymore.
   */
  function renounceOwnership() public onlyOwner {
    emit OwnershipRenounced(owner);
    owner = address(0);
  }

  /**
   * @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 {
    _transferOwnership(_newOwner);
  }

  /**
   * @dev Transfers control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function _transferOwnership(address _newOwner) internal {
    require(_newOwner != address(0));
    emit OwnershipTransferred(owner, _newOwner);
    owner = _newOwner;
  }
}

// File: openzeppelin-solidity/contracts/token/ERC20/MintableToken.sol

/**
 * @title Mintable token
 * @dev Simple ERC20 Token example, with mintable token creation
 * 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);
    _;
  }

  modifier hasMintPermission() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @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
  )
    public
    hasMintPermission
    canMint
    returns (bool)
  {
    totalSupply_ = totalSupply_.add(_amount);
    balances[_to] = balances[_to].add(_amount);
    emit Mint(_to, _amount);
    emit Transfer(address(0), _to, _amount);
    return true;
  }

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

// File: openzeppelin-solidity/contracts/token/ERC20/BurnableToken.sol

/**
 * @title Burnable Token
 * @dev Token that can be irreversibly burned (destroyed).
 */
contract BurnableToken is BasicToken {

  event Burn(address indexed burner, uint256 value);

  /**
   * @dev Burns a specific amount of tokens.
   * @param _value The amount of token to be burned.
   */
  function burn(uint256 _value) public {
    _burn(msg.sender, _value);
  }

  function _burn(address _who, uint256 _value) internal {
    require(_value <= balances[_who]);
    // no need to require value <= totalSupply, since that would imply the
    // sender's balance is greater than the totalSupply, which *should* be an assertion failure

    balances[_who] = balances[_who].sub(_value);
    totalSupply_ = totalSupply_.sub(_value);
    emit Burn(_who, _value);
    emit Transfer(_who, address(0), _value);
  }
}

// File: openzeppelin-solidity/contracts/lifecycle/Pausable.sol

/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() public onlyOwner whenNotPaused {
    paused = true;
    emit Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() public onlyOwner whenPaused {
    paused = false;
    emit Unpause();
  }
}

// File: openzeppelin-solidity/contracts/token/ERC20/PausableToken.sol

/**
 * @title Pausable token
 * @dev StandardToken modified with pausable transfers.
 **/
contract PausableToken is StandardToken, Pausable {

  function transfer(
    address _to,
    uint256 _value
  )
    public
    whenNotPaused
    returns (bool)
  {
    return super.transfer(_to, _value);
  }

  function transferFrom(
    address _from,
    address _to,
    uint256 _value
  )
    public
    whenNotPaused
    returns (bool)
  {
    return super.transferFrom(_from, _to, _value);
  }

  function approve(
    address _spender,
    uint256 _value
  )
    public
    whenNotPaused
    returns (bool)
  {
    return super.approve(_spender, _value);
  }

  function increaseApproval(
    address _spender,
    uint _addedValue
  )
    public
    whenNotPaused
    returns (bool success)
  {
    return super.increaseApproval(_spender, _addedValue);
  }

  function decreaseApproval(
    address _spender,
    uint _subtractedValue
  )
    public
    whenNotPaused
    returns (bool success)
  {
    return super.decreaseApproval(_spender, _subtractedValue);
  }
}

// File: openzeppelin-solidity/contracts/ownership/Claimable.sol

/**
 * @title Claimable
 * @dev Extension for the Ownable contract, where the ownership needs to be claimed.
 * This allows the new owner to accept the transfer.
 */
contract Claimable is Ownable {
  address public pendingOwner;

  /**
   * @dev Modifier throws if called by any account other than the pendingOwner.
   */
  modifier onlyPendingOwner() {
    require(msg.sender == pendingOwner);
    _;
  }

  /**
   * @dev Allows the current owner to set the pendingOwner address.
   * @param newOwner The address to transfer ownership to.
   */
  function transferOwnership(address newOwner) public onlyOwner {
    pendingOwner = newOwner;
  }

  /**
   * @dev Allows the pendingOwner address to finalize the transfer.
   */
  function claimOwnership() public onlyPendingOwner {
    emit OwnershipTransferred(owner, pendingOwner);
    owner = pendingOwner;
    pendingOwner = address(0);
  }
}

// File: openzeppelin-solidity/contracts/token/ERC20/SafeERC20.sol

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure.
 * To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
  function safeTransfer(
    ERC20Basic _token,
    address _to,
    uint256 _value
  )
    internal
  {
    require(_token.transfer(_to, _value));
  }

  function safeTransferFrom(
    ERC20 _token,
    address _from,
    address _to,
    uint256 _value
  )
    internal
  {
    require(_token.transferFrom(_from, _to, _value));
  }

  function safeApprove(
    ERC20 _token,
    address _spender,
    uint256 _value
  )
    internal
  {
    require(_token.approve(_spender, _value));
  }
}

// File: openzeppelin-solidity/contracts/ownership/CanReclaimToken.sol

/**
 * @title Contracts that should be able to recover tokens
 * @author SylTi
 * @dev This allow a contract to recover any ERC20 token received in a contract by transferring the balance to the contract owner.
 * This will prevent any accidental loss of tokens.
 */
contract CanReclaimToken is Ownable {
  using SafeERC20 for ERC20Basic;

  /**
   * @dev Reclaim all ERC20Basic compatible tokens
   * @param _token ERC20Basic The address of the token contract
   */
  function reclaimToken(ERC20Basic _token) external onlyOwner {
    uint256 balance = _token.balanceOf(this);
    _token.safeTransfer(owner, balance);
  }

}

// File: contracts/utils/OwnableContract.sol

// empty block is used as this contract just inherits others.
contract OwnableContract is CanReclaimToken, Claimable { } /* solhint-disable-line no-empty-blocks */

// File: contracts/token/WBTC.sol

contract WBTC is StandardToken, DetailedERC20("Wrapped BTC", "WBTC", 8),
    MintableToken, BurnableToken, PausableToken, OwnableContract {

    function burn(uint value) public onlyOwner {
        super.burn(value);
    }

    function finishMinting() public onlyOwner returns (bool) {
        return false;
    }

    function renounceOwnership() public onlyOwner {
        revert("renouncing ownership is blocked");
    }
}

// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity >=0.6.5 <0.9;
interface IERC20Token {
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    /// @dev send `value` token to `to` from `msg.sender`
    /// @param to The address of the recipient
    /// @param value The amount of token to be transferred
    /// @return True if transfer was successful
    function transfer(address to, uint256 value) external returns (bool);
    /// @dev send `value` token to `to` from `from` on the condition it is approved by `from`
    /// @param from The address of the sender
    /// @param to The address of the recipient
    /// @param value The amount of token to be transferred
    /// @return True if transfer was successful
    function transferFrom(address from, address to, uint256 value) external returns (bool);
    /// @dev `msg.sender` approves `spender` to spend `value` tokens
    /// @param spender The address of the account able to transfer the tokens
    /// @param value The amount of wei to be approved for transfer
    /// @return Always true if the call has enough gas to complete execution
    function approve(address spender, uint256 value) external returns (bool);
    /// @dev Query total supply of token
    /// @return Total supply of token
    function totalSupply() external view returns (uint256);
    /// @dev Get the balance of `owner`.
    /// @param owner The address from which the balance will be retrieved
    /// @return Balance of owner
    function balanceOf(address owner) external view returns (uint256);
    /// @dev Get the allowance for `spender` to spend from `owner`.
    /// @param owner The address of the account owning tokens
    /// @param spender The address of the account able to transfer the tokens
    /// @return Amount of remaining tokens allowed to spent
    function allowance(address owner, address spender) external view returns (uint256);
    /// @dev Get the number of decimals this token has.
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./IERC20Token.sol";
interface IEtherToken is IERC20Token {
    /// @dev Wrap ether.
    function deposit() external payable;
    /// @dev Unwrap ether.
    function withdraw(uint256 amount) external;
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
import "./errors/LibRichErrorsV06.sol";
import "./errors/LibSafeMathRichErrorsV06.sol";
library LibSafeMathV06 {
    function safeMul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        if (c / a != b) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.MULTIPLICATION_OVERFLOW,
                    a,
                    b
                )
            );
        }
        return c;
    }
    function safeDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        if (b == 0) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.DIVISION_BY_ZERO,
                    a,
                    b
                )
            );
        }
        uint256 c = a / b;
        return c;
    }
    function safeSub(uint256 a, uint256 b) internal pure returns (uint256) {
        if (b > a) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.SUBTRACTION_UNDERFLOW,
                    a,
                    b
                )
            );
        }
        return a - b;
    }
    function safeAdd(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        if (c < a) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.ADDITION_OVERFLOW,
                    a,
                    b
                )
            );
        }
        return c;
    }
    function max256(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }
    function min256(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }
    function safeMul128(uint128 a, uint128 b) internal pure returns (uint128) {
        if (a == 0) {
            return 0;
        }
        uint128 c = a * b;
        if (c / a != b) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.MULTIPLICATION_OVERFLOW,
                    a,
                    b
                )
            );
        }
        return c;
    }
    function safeDiv128(uint128 a, uint128 b) internal pure returns (uint128) {
        if (b == 0) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.DIVISION_BY_ZERO,
                    a,
                    b
                )
            );
        }
        uint128 c = a / b;
        return c;
    }
    function safeSub128(uint128 a, uint128 b) internal pure returns (uint128) {
        if (b > a) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.SUBTRACTION_UNDERFLOW,
                    a,
                    b
                )
            );
        }
        return a - b;
    }
    function safeAdd128(uint128 a, uint128 b) internal pure returns (uint128) {
        uint128 c = a + b;
        if (c < a) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256BinOpError(
                    LibSafeMathRichErrorsV06.BinOpErrorCodes.ADDITION_OVERFLOW,
                    a,
                    b
                )
            );
        }
        return c;
    }
    function max128(uint128 a, uint128 b) internal pure returns (uint128) {
        return a >= b ? a : b;
    }
    function min128(uint128 a, uint128 b) internal pure returns (uint128) {
        return a < b ? a : b;
    }
    function safeDowncastToUint128(uint256 a) internal pure returns (uint128) {
        if (a > type(uint128).max) {
            LibRichErrorsV06.rrevert(
                LibSafeMathRichErrorsV06.Uint256DowncastError(
                    LibSafeMathRichErrorsV06.DowncastErrorCodes.VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT128,
                    a
                )
            );
        }
        return uint128(a);
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibRichErrorsV06 {
    // bytes4(keccak256("Error(string)"))
    bytes4 internal constant STANDARD_ERROR_SELECTOR = 0x08c379a0;
    /// @dev ABI encode a standard, string revert error payload.
    ///      This is the same payload that would be included by a `revert(string)`
    ///      solidity statement. It has the function signature `Error(string)`.
    /// @param message The error string.
    /// @return The ABI encoded error.
    function StandardError(string memory message) internal pure returns (bytes memory) {
        return abi.encodeWithSelector(STANDARD_ERROR_SELECTOR, bytes(message));
    }
    /// @dev Reverts an encoded rich revert reason `errorData`.
    /// @param errorData ABI encoded error data.
    function rrevert(bytes memory errorData) internal pure {
        assembly {
            revert(add(errorData, 0x20), mload(errorData))
        }
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibSafeMathRichErrorsV06 {
    // bytes4(keccak256("Uint256BinOpError(uint8,uint256,uint256)"))
    bytes4 internal constant UINT256_BINOP_ERROR_SELECTOR = 0xe946c1bb;
    // bytes4(keccak256("Uint256DowncastError(uint8,uint256)"))
    bytes4 internal constant UINT256_DOWNCAST_ERROR_SELECTOR = 0xc996af7b;
    enum BinOpErrorCodes {
        ADDITION_OVERFLOW,
        MULTIPLICATION_OVERFLOW,
        SUBTRACTION_UNDERFLOW,
        DIVISION_BY_ZERO
    }
    enum DowncastErrorCodes {
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT32,
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT64,
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT96,
        VALUE_TOO_LARGE_TO_DOWNCAST_TO_UINT128
    }
    function Uint256BinOpError(BinOpErrorCodes errorCode, uint256 a, uint256 b) internal pure returns (bytes memory) {
        return abi.encodeWithSelector(UINT256_BINOP_ERROR_SELECTOR, errorCode, a, b);
    }
    function Uint256DowncastError(DowncastErrorCodes errorCode, uint256 a) internal pure returns (bytes memory) {
        return abi.encodeWithSelector(UINT256_DOWNCAST_ERROR_SELECTOR, errorCode, a);
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2020 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
interface IOwnableV06 {
    /// @dev Emitted by Ownable when ownership is transferred.
    /// @param previousOwner The previous owner of the contract.
    /// @param newOwner The new owner of the contract.
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /// @dev Transfers ownership of the contract to a new address.
    /// @param newOwner The address that will become the owner.
    function transferOwnership(address newOwner) external;
    /// @dev The owner of this contract.
    /// @return ownerAddress The owner address.
    function owner() external view returns (address ownerAddress);
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibCommonRichErrors {
    function OnlyCallableBySelfError(address sender) internal pure returns (bytes memory) {
        return abi.encodeWithSelector(bytes4(keccak256("OnlyCallableBySelfError(address)")), sender);
    }
    function IllegalReentrancyError(bytes4 selector, uint256 reentrancyFlags) internal pure returns (bytes memory) {
        return
            abi.encodeWithSelector(
                bytes4(keccak256("IllegalReentrancyError(bytes4,uint256)")),
                selector,
                reentrancyFlags
            );
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
library LibOwnableRichErrors {
    function OnlyOwnerError(address sender, address owner) internal pure returns (bytes memory) {
        return abi.encodeWithSelector(bytes4(keccak256("OnlyOwnerError(address,address)")), sender, owner);
    }
    function TransferOwnerToZeroError() internal pure returns (bytes memory) {
        return abi.encodeWithSelector(bytes4(keccak256("TransferOwnerToZeroError()")));
    }
    function MigrateCallFailedError(address target, bytes memory resultData) internal pure returns (bytes memory) {
        return abi.encodeWithSelector(bytes4(keccak256("MigrateCallFailedError(address,bytes)")), target, resultData);
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/src/IERC20Token.sol";
import "@0x/contracts-erc20/src/IEtherToken.sol";
import "../vendor/IUniswapV3Pool.sol";
import "../migrations/LibMigrate.sol";
import "../fixins/FixinCommon.sol";
import "../fixins/FixinTokenSpender.sol";
import "./interfaces/IFeature.sol";
import "./interfaces/IUniswapV3Feature.sol";
/// @dev VIP uniswap fill functions.
contract UniswapV3Feature is IFeature, IUniswapV3Feature, FixinCommon, FixinTokenSpender {
    /// @dev Name of this feature.
    string public constant override FEATURE_NAME = "UniswapV3Feature";
    /// @dev Version of this feature.
    uint256 public immutable override FEATURE_VERSION = _encodeVersion(1, 1, 0);
    /// @dev WETH contract.
    IEtherToken private immutable WETH;
    /// @dev UniswapV3 Factory contract address prepended with '0xff' and left-aligned.
    bytes32 private immutable UNI_FF_FACTORY_ADDRESS;
    /// @dev UniswapV3 pool init code hash.
    bytes32 private immutable UNI_POOL_INIT_CODE_HASH;
    /// @dev Minimum size of an encoded swap path:
    ///      sizeof(address(inputToken) | uint24(fee) | address(outputToken))
    uint256 private constant SINGLE_HOP_PATH_SIZE = 20 + 3 + 20;
    /// @dev How many bytes to skip ahead in an encoded path to start at the next hop:
    ///      sizeof(address(inputToken) | uint24(fee))
    uint256 private constant PATH_SKIP_HOP_SIZE = 20 + 3;
    /// @dev The size of the swap callback data.
    uint256 private constant SWAP_CALLBACK_DATA_SIZE = 128;
    /// @dev Minimum tick price sqrt ratio.
    uint160 internal constant MIN_PRICE_SQRT_RATIO = 4295128739;
    /// @dev Minimum tick price sqrt ratio.
    uint160 internal constant MAX_PRICE_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;
    /// @dev Mask of lower 20 bytes.
    uint256 private constant ADDRESS_MASK = 0x00ffffffffffffffffffffffffffffffffffffffff;
    /// @dev Mask of lower 3 bytes.
    uint256 private constant UINT24_MASK = 0xffffff;
    /// @dev Construct this contract.
    /// @param weth The WETH contract.
    /// @param uniFactory The UniswapV3 factory contract.
    /// @param poolInitCodeHash The UniswapV3 pool init code hash.
    constructor(IEtherToken weth, address uniFactory, bytes32 poolInitCodeHash) public {
        WETH = weth;
        UNI_FF_FACTORY_ADDRESS = bytes32((uint256(0xff) << 248) | (uint256(uniFactory) << 88));
        UNI_POOL_INIT_CODE_HASH = poolInitCodeHash;
    }
    /// @dev Initialize and register this feature.
    ///      Should be delegatecalled by `Migrate.migrate()`.
    /// @return success `LibMigrate.SUCCESS` on success.
    function migrate() external returns (bytes4 success) {
        _registerFeatureFunction(this.sellEthForTokenToUniswapV3.selector);
        _registerFeatureFunction(this.sellTokenForEthToUniswapV3.selector);
        _registerFeatureFunction(this.sellTokenForTokenToUniswapV3.selector);
        _registerFeatureFunction(this._sellTokenForTokenToUniswapV3.selector);
        _registerFeatureFunction(this._sellHeldTokenForTokenToUniswapV3.selector);
        _registerFeatureFunction(this.uniswapV3SwapCallback.selector);
        return LibMigrate.MIGRATE_SUCCESS;
    }
    /// @dev Sell attached ETH directly against uniswap v3.
    /// @param encodedPath Uniswap-encoded path, where the first token is WETH.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @return buyAmount Amount of the last token in the path bought.
    function sellEthForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 minBuyAmount,
        address recipient
    ) public payable override returns (uint256 buyAmount) {
        // Wrap ETH.
        WETH.deposit{value: msg.value}();
        return
            _swap(
                encodedPath,
                msg.value,
                minBuyAmount,
                address(this), // we are payer because we hold the WETH
                _normalizeRecipient(recipient)
            );
    }
    /// @dev Sell a token for ETH directly against uniswap v3.
    /// @param encodedPath Uniswap-encoded path, where the last token is WETH.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of ETH to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of ETH bought.
    function sellTokenForEthToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address payable recipient
    ) public override returns (uint256 buyAmount) {
        buyAmount = _swap(
            encodedPath,
            sellAmount,
            minBuyAmount,
            msg.sender,
            address(this) // we are recipient because we need to unwrap WETH
        );
        WETH.withdraw(buyAmount);
        // Transfer ETH to recipient.
        (bool success, bytes memory revertData) = _normalizeRecipient(recipient).call{value: buyAmount}("");
        if (!success) {
            revertData.rrevert();
        }
    }
    /// @dev Sell a token for another token directly against uniswap v3.
    /// @param encodedPath Uniswap-encoded path.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of the last token in the path bought.
    function sellTokenForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address recipient
    ) public override returns (uint256 buyAmount) {
        buyAmount = _swap(encodedPath, sellAmount, minBuyAmount, msg.sender, _normalizeRecipient(recipient));
    }
    /// @dev Sell a token for another token directly against uniswap v3. Internal variant.
    /// @param encodedPath Uniswap-encoded path.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for payer.
    /// @param payer The address to pull the sold tokens from.
    /// @return buyAmount Amount of the last token in the path bought.
    function _sellTokenForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address recipient,
        address payer
    ) public override onlySelf returns (uint256 buyAmount) {
        buyAmount = _swap(encodedPath, sellAmount, minBuyAmount, payer, _normalizeRecipient(recipient, payer));
    }
    /// @dev Sell a token for another token directly against uniswap v3.
    ///      Private variant, uses tokens held by `address(this)`.
    /// @param encodedPath Uniswap-encoded path.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of the last token in the path bought.
    function _sellHeldTokenForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address recipient
    ) public override onlySelf returns (uint256 buyAmount) {
        buyAmount = _swap(encodedPath, sellAmount, minBuyAmount, address(this), _normalizeRecipient(recipient));
    }
    /// @dev The UniswapV3 pool swap callback which pays the funds requested
    ///      by the caller/pool to the pool. Can only be called by a valid
    ///      UniswapV3 pool.
    /// @param amount0Delta Token0 amount owed.
    /// @param amount1Delta Token1 amount owed.
    /// @param data Arbitrary data forwarded from swap() caller. An ABI-encoded
    ///        struct of: inputToken, outputToken, fee, payer
    function uniswapV3SwapCallback(int256 amount0Delta, int256 amount1Delta, bytes calldata data) external override {
        IERC20Token token0;
        IERC20Token token1;
        address payer;
        {
            uint24 fee;
            // Decode the data.
            require(data.length == SWAP_CALLBACK_DATA_SIZE, "UniswapFeature/INVALID_SWAP_CALLBACK_DATA");
            assembly {
                let p := add(36, calldataload(68))
                token0 := calldataload(p)
                token1 := calldataload(add(p, 32))
                fee := calldataload(add(p, 64))
                payer := calldataload(add(p, 96))
            }
            (token0, token1) = token0 < token1 ? (token0, token1) : (token1, token0);
            // Only a valid pool contract can call this function.
            require(
                msg.sender == address(_toPool(token0, fee, token1)),
                "UniswapV3Feature/INVALID_SWAP_CALLBACK_CALLER"
            );
        }
        // Pay the amount owed to the pool.
        if (amount0Delta > 0) {
            _pay(token0, payer, msg.sender, uint256(amount0Delta));
        } else if (amount1Delta > 0) {
            _pay(token1, payer, msg.sender, uint256(amount1Delta));
        } else {
            revert("UniswapV3Feature/INVALID_SWAP_AMOUNTS");
        }
    }
    // Executes successive swaps along an encoded uniswap path.
    function _swap(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address payer,
        address recipient
    ) private returns (uint256 buyAmount) {
        if (sellAmount != 0) {
            require(sellAmount <= uint256(type(int256).max), "UniswapV3Feature/SELL_AMOUNT_OVERFLOW");
            // Perform a swap for each hop in the path.
            bytes memory swapCallbackData = new bytes(SWAP_CALLBACK_DATA_SIZE);
            while (true) {
                bool isPathMultiHop = _isPathMultiHop(encodedPath);
                bool zeroForOne;
                IUniswapV3Pool pool;
                {
                    (IERC20Token inputToken, uint24 fee, IERC20Token outputToken) = _decodeFirstPoolInfoFromPath(
                        encodedPath
                    );
                    pool = _toPool(inputToken, fee, outputToken);
                    zeroForOne = inputToken < outputToken;
                    _updateSwapCallbackData(swapCallbackData, inputToken, outputToken, fee, payer);
                }
                (int256 amount0, int256 amount1) = pool.swap(
                    // Intermediate tokens go to this contract.
                    isPathMultiHop ? address(this) : recipient,
                    zeroForOne,
                    int256(sellAmount),
                    zeroForOne ? MIN_PRICE_SQRT_RATIO + 1 : MAX_PRICE_SQRT_RATIO - 1,
                    swapCallbackData
                );
                {
                    int256 _buyAmount = -(zeroForOne ? amount1 : amount0);
                    require(_buyAmount >= 0, "UniswapV3Feature/INVALID_BUY_AMOUNT");
                    buyAmount = uint256(_buyAmount);
                }
                if (!isPathMultiHop) {
                    // Done.
                    break;
                }
                // Continue with next hop.
                payer = address(this); // Subsequent hops are paid for by us.
                sellAmount = buyAmount;
                // Skip to next hop along path.
                encodedPath = _shiftHopFromPathInPlace(encodedPath);
            }
        }
        require(minBuyAmount <= buyAmount, "UniswapV3Feature/UNDERBOUGHT");
    }
    // Pay tokens from `payer` to `to`, using `transferFrom()` if
    // `payer` != this contract.
    function _pay(IERC20Token token, address payer, address to, uint256 amount) private {
        if (payer != address(this)) {
            _transferERC20TokensFrom(token, payer, to, amount);
        } else {
            _transferERC20Tokens(token, to, amount);
        }
    }
    // Update `swapCallbackData` in place with new values.
    function _updateSwapCallbackData(
        bytes memory swapCallbackData,
        IERC20Token inputToken,
        IERC20Token outputToken,
        uint24 fee,
        address payer
    ) private pure {
        assembly {
            let p := add(swapCallbackData, 32)
            mstore(p, inputToken)
            mstore(add(p, 32), outputToken)
            mstore(add(p, 64), and(UINT24_MASK, fee))
            mstore(add(p, 96), and(ADDRESS_MASK, payer))
        }
    }
    // Compute the pool address given two tokens and a fee.
    function _toPool(
        IERC20Token inputToken,
        uint24 fee,
        IERC20Token outputToken
    ) private view returns (IUniswapV3Pool pool) {
        // address(keccak256(abi.encodePacked(
        //     hex"ff",
        //     UNI_FACTORY_ADDRESS,
        //     keccak256(abi.encode(inputToken, outputToken, fee)),
        //     UNI_POOL_INIT_CODE_HASH
        // )))
        bytes32 ffFactoryAddress = UNI_FF_FACTORY_ADDRESS;
        bytes32 poolInitCodeHash = UNI_POOL_INIT_CODE_HASH;
        (IERC20Token token0, IERC20Token token1) = inputToken < outputToken
            ? (inputToken, outputToken)
            : (outputToken, inputToken);
        assembly {
            let s := mload(0x40)
            let p := s
            mstore(p, ffFactoryAddress)
            p := add(p, 21)
            // Compute the inner hash in-place
            mstore(p, token0)
            mstore(add(p, 32), token1)
            mstore(add(p, 64), and(UINT24_MASK, fee))
            mstore(p, keccak256(p, 96))
            p := add(p, 32)
            mstore(p, poolInitCodeHash)
            pool := and(ADDRESS_MASK, keccak256(s, 85))
        }
    }
    // Return whether or not an encoded uniswap path contains more than one hop.
    function _isPathMultiHop(bytes memory encodedPath) private pure returns (bool isMultiHop) {
        return encodedPath.length > SINGLE_HOP_PATH_SIZE;
    }
    // Return the first input token, output token, and fee of an encoded uniswap path.
    function _decodeFirstPoolInfoFromPath(
        bytes memory encodedPath
    ) private pure returns (IERC20Token inputToken, uint24 fee, IERC20Token outputToken) {
        require(encodedPath.length >= SINGLE_HOP_PATH_SIZE, "UniswapV3Feature/BAD_PATH_ENCODING");
        assembly {
            let p := add(encodedPath, 32)
            inputToken := shr(96, mload(p))
            p := add(p, 20)
            fee := shr(232, mload(p))
            p := add(p, 3)
            outputToken := shr(96, mload(p))
        }
    }
    // Skip past the first hop of an encoded uniswap path in-place.
    function _shiftHopFromPathInPlace(bytes memory encodedPath) private pure returns (bytes memory shiftedEncodedPath) {
        require(encodedPath.length >= PATH_SKIP_HOP_SIZE, "UniswapV3Feature/BAD_PATH_ENCODING");
        uint256 shiftSize = PATH_SKIP_HOP_SIZE;
        uint256 newSize = encodedPath.length - shiftSize;
        assembly {
            shiftedEncodedPath := add(encodedPath, shiftSize)
            mstore(shiftedEncodedPath, newSize)
        }
    }
    // Convert null address values to alternative address.
    function _normalizeRecipient(
        address recipient,
        address alternative
    ) private pure returns (address payable normalizedRecipient) {
        return recipient == address(0) ? payable(alternative) : payable(recipient);
    }
    // Convert null address values to msg.sender.
    function _normalizeRecipient(address recipient) private view returns (address payable normalizedRecipient) {
        return _normalizeRecipient(recipient, msg.sender);
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Basic interface for a feature contract.
interface IFeature {
    /// @dev The name of this feature set.
    function FEATURE_NAME() external view returns (string memory name);
    /// @dev The version of this feature set.
    function FEATURE_VERSION() external view returns (uint256 version);
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/interfaces/IOwnableV06.sol";
/// @dev Owner management and migration features.
interface IOwnableFeature is IOwnableV06 {
    /// @dev Emitted when `migrate()` is called.
    /// @param caller The caller of `migrate()`.
    /// @param migrator The migration contract.
    /// @param newOwner The address of the new owner.
    event Migrated(address caller, address migrator, address newOwner);
    /// @dev Execute a migration function in the context of the ZeroEx contract.
    ///      The result of the function being called should be the magic bytes
    ///      0x2c64c5ef (`keccack('MIGRATE_SUCCESS')`). Only callable by the owner.
    ///      The owner will be temporarily set to `address(this)` inside the call.
    ///      Before returning, the owner will be set to `newOwner`.
    /// @param target The migrator contract address.
    /// @param newOwner The address of the new owner.
    /// @param data The call data.
    function migrate(address target, bytes calldata data, address newOwner) external;
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev Basic registry management features.
interface ISimpleFunctionRegistryFeature {
    /// @dev A function implementation was updated via `extend()` or `rollback()`.
    /// @param selector The function selector.
    /// @param oldImpl The implementation contract address being replaced.
    /// @param newImpl The replacement implementation contract address.
    event ProxyFunctionUpdated(bytes4 indexed selector, address oldImpl, address newImpl);
    /// @dev Roll back to a prior implementation of a function.
    /// @param selector The function selector.
    /// @param targetImpl The address of an older implementation of the function.
    function rollback(bytes4 selector, address targetImpl) external;
    /// @dev Register or replace a function.
    /// @param selector The function selector.
    /// @param impl The implementation contract for the function.
    function extend(bytes4 selector, address impl) external;
    /// @dev Retrieve the length of the rollback history for a function.
    /// @param selector The function selector.
    /// @return rollbackLength The number of items in the rollback history for
    ///         the function.
    function getRollbackLength(bytes4 selector) external view returns (uint256 rollbackLength);
    /// @dev Retrieve an entry in the rollback history for a function.
    /// @param selector The function selector.
    /// @param idx The index in the rollback history.
    /// @return impl An implementation address for the function at
    ///         index `idx`.
    function getRollbackEntryAtIndex(bytes4 selector, uint256 idx) external view returns (address impl);
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
/// @dev VIP uniswap v3 fill functions.
interface IUniswapV3Feature {
    /// @dev Sell attached ETH directly against uniswap v3.
    /// @param encodedPath Uniswap-encoded path, where the first token is WETH.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of the last token in the path bought.
    function sellEthForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 minBuyAmount,
        address recipient
    ) external payable returns (uint256 buyAmount);
    /// @dev Sell a token for ETH directly against uniswap v3.
    /// @param encodedPath Uniswap-encoded path, where the last token is WETH.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of ETH to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of ETH bought.
    function sellTokenForEthToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address payable recipient
    ) external returns (uint256 buyAmount);
    /// @dev Sell a token for another token directly against uniswap v3.
    /// @param encodedPath Uniswap-encoded path.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of the last token in the path bought.
    function sellTokenForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address recipient
    ) external returns (uint256 buyAmount);
    /// @dev Sell a token for another token directly against uniswap v3. Internal variant.
    /// @param encodedPath Uniswap-encoded path.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for payer.
    /// @param payer The address to pull the sold tokens from.
    /// @return buyAmount Amount of the last token in the path bought.
    function _sellTokenForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address recipient,
        address payer
    ) external returns (uint256 buyAmount);
    /// @dev Sell a token for another token directly against uniswap v3.
    ///      Private variant, uses tokens held by `address(this)`.
    /// @param encodedPath Uniswap-encoded path.
    /// @param sellAmount amount of the first token in the path to sell.
    /// @param minBuyAmount Minimum amount of the last token in the path to buy.
    /// @param recipient The recipient of the bought tokens. Can be zero for sender.
    /// @return buyAmount Amount of the last token in the path bought.
    function _sellHeldTokenForTokenToUniswapV3(
        bytes memory encodedPath,
        uint256 sellAmount,
        uint256 minBuyAmount,
        address recipient
    ) external returns (uint256 buyAmount);
    /// @dev The UniswapV3 pool swap callback which pays the funds requested
    ///      by the caller/pool to the pool. Can only be called by a valid
    ///      UniswapV3 pool.
    /// @param amount0Delta Token0 amount owed.
    /// @param amount1Delta Token1 amount owed.
    /// @param data Arbitrary data forwarded from swap() caller. An ABI-encoded
    ///        struct of: inputToken, outputToken, fee, payer
    function uniswapV3SwapCallback(int256 amount0Delta, int256 amount1Delta, bytes calldata data) external;
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../errors/LibCommonRichErrors.sol";
import "../errors/LibOwnableRichErrors.sol";
import "../features/interfaces/IOwnableFeature.sol";
import "../features/interfaces/ISimpleFunctionRegistryFeature.sol";
/// @dev Common feature utilities.
abstract contract FixinCommon {
    using LibRichErrorsV06 for bytes;
    /// @dev The implementation address of this feature.
    address internal immutable _implementation;
    /// @dev The caller must be this contract.
    modifier onlySelf() virtual {
        if (msg.sender != address(this)) {
            LibCommonRichErrors.OnlyCallableBySelfError(msg.sender).rrevert();
        }
        _;
    }
    /// @dev The caller of this function must be the owner.
    modifier onlyOwner() virtual {
        {
            address owner = IOwnableFeature(address(this)).owner();
            if (msg.sender != owner) {
                LibOwnableRichErrors.OnlyOwnerError(msg.sender, owner).rrevert();
            }
        }
        _;
    }
    constructor() internal {
        // Remember this feature's original address.
        _implementation = address(this);
    }
    /// @dev Registers a function implemented by this feature at `_implementation`.
    ///      Can and should only be called within a `migrate()`.
    /// @param selector The selector of the function whose implementation
    ///        is at `_implementation`.
    function _registerFeatureFunction(bytes4 selector) internal {
        ISimpleFunctionRegistryFeature(address(this)).extend(selector, _implementation);
    }
    /// @dev Encode a feature version as a `uint256`.
    /// @param major The major version number of the feature.
    /// @param minor The minor version number of the feature.
    /// @param revision The revision number of the feature.
    /// @return encodedVersion The encoded version number.
    function _encodeVersion(
        uint32 major,
        uint32 minor,
        uint32 revision
    ) internal pure returns (uint256 encodedVersion) {
        return (uint256(major) << 64) | (uint256(minor) << 32) | uint256(revision);
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-erc20/src/IERC20Token.sol";
import "@0x/contracts-utils/contracts/src/v06/LibSafeMathV06.sol";
/// @dev Helpers for moving tokens around.
abstract contract FixinTokenSpender {
    // Mask of the lower 20 bytes of a bytes32.
    uint256 private constant ADDRESS_MASK = 0x000000000000000000000000ffffffffffffffffffffffffffffffffffffffff;
    /// @dev Transfers ERC20 tokens from `owner` to `to`.
    /// @param token The token to spend.
    /// @param owner The owner of the tokens.
    /// @param to The recipient of the tokens.
    /// @param amount The amount of `token` to transfer.
    function _transferERC20TokensFrom(IERC20Token token, address owner, address to, uint256 amount) internal {
        require(address(token) != address(this), "FixinTokenSpender/CANNOT_INVOKE_SELF");
        assembly {
            let ptr := mload(0x40) // free memory pointer
            // selector for transferFrom(address,address,uint256)
            mstore(ptr, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(ptr, 0x04), and(owner, ADDRESS_MASK))
            mstore(add(ptr, 0x24), and(to, ADDRESS_MASK))
            mstore(add(ptr, 0x44), amount)
            let success := call(gas(), and(token, ADDRESS_MASK), 0, ptr, 0x64, ptr, 32)
            let rdsize := returndatasize()
            // Check for ERC20 success. ERC20 tokens should return a boolean,
            // but some don't. We accept 0-length return data as success, or at
            // least 32 bytes that starts with a 32-byte boolean true.
            success := and(
                success, // call itself succeeded
                or(
                    iszero(rdsize), // no return data, or
                    and(
                        iszero(lt(rdsize, 32)), // at least 32 bytes
                        eq(mload(ptr), 1) // starts with uint256(1)
                    )
                )
            )
            if iszero(success) {
                returndatacopy(ptr, 0, rdsize)
                revert(ptr, rdsize)
            }
        }
    }
    /// @dev Transfers ERC20 tokens from ourselves to `to`.
    /// @param token The token to spend.
    /// @param to The recipient of the tokens.
    /// @param amount The amount of `token` to transfer.
    function _transferERC20Tokens(IERC20Token token, address to, uint256 amount) internal {
        require(address(token) != address(this), "FixinTokenSpender/CANNOT_INVOKE_SELF");
        assembly {
            let ptr := mload(0x40) // free memory pointer
            // selector for transfer(address,uint256)
            mstore(ptr, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(ptr, 0x04), and(to, ADDRESS_MASK))
            mstore(add(ptr, 0x24), amount)
            let success := call(gas(), and(token, ADDRESS_MASK), 0, ptr, 0x44, ptr, 32)
            let rdsize := returndatasize()
            // Check for ERC20 success. ERC20 tokens should return a boolean,
            // but some don't. We accept 0-length return data as success, or at
            // least 32 bytes that starts with a 32-byte boolean true.
            success := and(
                success, // call itself succeeded
                or(
                    iszero(rdsize), // no return data, or
                    and(
                        iszero(lt(rdsize, 32)), // at least 32 bytes
                        eq(mload(ptr), 1) // starts with uint256(1)
                    )
                )
            )
            if iszero(success) {
                returndatacopy(ptr, 0, rdsize)
                revert(ptr, rdsize)
            }
        }
    }
    /// @dev Transfers some amount of ETH to the given recipient and
    ///      reverts if the transfer fails.
    /// @param recipient The recipient of the ETH.
    /// @param amount The amount of ETH to transfer.
    function _transferEth(address payable recipient, uint256 amount) internal {
        if (amount > 0) {
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "FixinTokenSpender::_transferEth/TRANSFER_FAILED");
        }
    }
    /// @dev Gets the maximum amount of an ERC20 token `token` that can be
    ///      pulled from `owner` by this address.
    /// @param token The token to spend.
    /// @param owner The owner of the tokens.
    /// @return amount The amount of tokens that can be pulled.
    function _getSpendableERC20BalanceOf(IERC20Token token, address owner) internal view returns (uint256) {
        return LibSafeMathV06.min256(token.allowance(owner, address(this)), token.balanceOf(owner));
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.5;
pragma experimental ABIEncoderV2;
import "@0x/contracts-utils/contracts/src/v06/errors/LibRichErrorsV06.sol";
import "../errors/LibOwnableRichErrors.sol";
library LibMigrate {
    /// @dev Magic bytes returned by a migrator to indicate success.
    ///      This is `keccack('MIGRATE_SUCCESS')`.
    bytes4 internal constant MIGRATE_SUCCESS = 0x2c64c5ef;
    using LibRichErrorsV06 for bytes;
    /// @dev Perform a delegatecall and ensure it returns the magic bytes.
    /// @param target The call target.
    /// @param data The call data.
    function delegatecallMigrateFunction(address target, bytes memory data) internal {
        (bool success, bytes memory resultData) = target.delegatecall(data);
        if (!success || resultData.length != 32 || abi.decode(resultData, (bytes4)) != MIGRATE_SUCCESS) {
            LibOwnableRichErrors.MigrateCallFailedError(target, resultData).rrevert();
        }
    }
}
// SPDX-License-Identifier: Apache-2.0
/*
  Copyright 2023 ZeroEx Intl.
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
*/
pragma solidity ^0.6.12;
interface IUniswapV3Pool {
    /// @notice Swap token0 for token1, or token1 for token0
    /// @dev The caller of this method receives a callback in the form of IUniswapV3SwapCallback#uniswapV3SwapCallback
    /// @param recipient The address to receive the output of the swap
    /// @param zeroForOne The direction of the swap, true for token0 to token1, false for token1 to token0
    /// @param amountSpecified The amount of the swap, which implicitly configures the swap as exact input (positive),
    /// or exact output (negative)
    /// @param sqrtPriceLimitX96 The Q64.96 sqrt price limit. If zero for one, the price cannot be less than this
    /// value after the swap. If one for zero, the price cannot be greater than this value after the swap
    /// @param data Any data to be passed through to the callback
    /// @return amount0 The delta of the balance of token0 of the pool, exact when negative, minimum when positive
    /// @return amount1 The delta of the balance of token1 of the pool, exact when negative, minimum when positive
    function swap(
        address recipient,
        bool zeroForOne,
        int256 amountSpecified,
        uint160 sqrtPriceLimitX96,
        bytes calldata data
    ) external returns (int256 amount0, int256 amount1);
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "openzeppelin-contracts-upgradeable/contracts/token/ERC20/extensions/draft-ERC20PermitUpgradeable.sol";
import "openzeppelin-contracts-upgradeable/contracts/access/Ownable2StepUpgradeable.sol";
import "openzeppelin-contracts-upgradeable/contracts/security/PausableUpgradeable.sol";
contract Stablecoin is ERC20PermitUpgradeable, Ownable2StepUpgradeable, PausableUpgradeable {
    mapping(address => bool) public frozen;
    event Mint(address indexed caller, address indexed to, uint256 amount);
    event Burn(address indexed caller, address indexed from, uint256 amount);
    event Freeze(address indexed caller, address indexed account);
    event Unfreeze(address indexed caller, address indexed account);
    function initialize(string memory _name, string memory _symbol) public initializer {
        __Context_init();
        __ERC20_init(_name, _symbol);
        __ERC20Permit_init(_name);
        __Ownable2Step_init();
        __Pausable_init();
    }
    
    /**
     * @dev Throws if account is frozen.
     */
    modifier notFrozen(address account) {
        require(!frozen[account], "Account is frozen");
        _;
    }
    /** 
     * @dev See {ERC20-_mint}.
     * @param amount Mint amount
     * @return True if successful
     * Can only be called by the current owner.
     */
    function mint(uint256 amount) external onlyOwner returns (bool) {
        _mint(_msgSender(), amount);
        emit Mint(_msgSender(), _msgSender(), amount);
        return true;
    }
    /**
     * @dev See {ERC20-_burn}.
     * @param amount Burn amount
     * @return True if successful
     * Can only be called by the current owner.
     */
    function burn(uint256 amount) external onlyOwner returns (bool) {
        _burn(_msgSender(), amount);
        emit Burn(_msgSender(), _msgSender(), amount);
        return true;
    }
    
    /**
     * @dev Adds account to frozen state.
     * Can only be called by the current owner.
     */
    function freeze(address account) external onlyOwner {
        frozen[account] = true;
        emit Freeze(_msgSender(), account);
    }
    /**
     * @dev Removes account from frozen state.
     * Can only be called by the current owner.
     */
    function unfreeze(address account) external onlyOwner {
        delete frozen[account];
        emit Unfreeze(_msgSender(), account);
    }
    /**
     * @dev Triggers stopped state.
     * Can only be called by the current owner.
     */
    function pause() external onlyOwner {
        _pause();
    }
    /**
     * @dev Returns to normal state.
     * Can only be called by the current owner.
     */
    function unpause() external onlyOwner {
        _unpause();
    }
    /**
     * @dev Unsupported. Leaves the contract without owner.
     */
    function renounceOwnership() public view override onlyOwner {
        revert("Unsupported");
    }
    /**
     * @dev See {ERC20-_transfer}.
     * @param from Source address
     * @param to Destination address
     * @param amount Transfer amount
     */
    function _transfer(address from, address to, uint256 amount) internal override whenNotPaused notFrozen(from) notFrozen(to) {
        super._transfer(from, to, amount);
    }
    /**
     * @dev See {ERC20-_approve}.
     * @param owner Owners's address
     * @param spender Spender's address
     * @param amount Allowance amount
     */
    function _approve(address owner, address spender, uint256 amount) internal override whenNotPaused notFrozen(owner) notFrozen(spender) {
        super._approve(owner, spender, amount);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/extensions/draft-ERC20Permit.sol)
pragma solidity ^0.8.0;
import "./draft-IERC20PermitUpgradeable.sol";
import "../ERC20Upgradeable.sol";
import "../../../utils/cryptography/ECDSAUpgradeable.sol";
import "../../../utils/cryptography/EIP712Upgradeable.sol";
import "../../../utils/CountersUpgradeable.sol";
import "../../../proxy/utils/Initializable.sol";
/**
 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * _Available since v3.4._
 *
 * @custom:storage-size 51
 */
abstract contract ERC20PermitUpgradeable is Initializable, ERC20Upgradeable, IERC20PermitUpgradeable, EIP712Upgradeable {
    using CountersUpgradeable for CountersUpgradeable.Counter;
    mapping(address => CountersUpgradeable.Counter) private _nonces;
    // solhint-disable-next-line var-name-mixedcase
    bytes32 private constant _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    /**
     * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
     * However, to ensure consistency with the upgradeable transpiler, we will continue
     * to reserve a slot.
     * @custom:oz-renamed-from _PERMIT_TYPEHASH
     */
    // solhint-disable-next-line var-name-mixedcase
    bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;
    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC20 token name.
     */
    function __ERC20Permit_init(string memory name) internal onlyInitializing {
        __EIP712_init_unchained(name, "1");
    }
    function __ERC20Permit_init_unchained(string memory) internal onlyInitializing {}
    /**
     * @dev See {IERC20Permit-permit}.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual override {
        require(block.timestamp <= deadline, "ERC20Permit: expired deadline");
        bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));
        bytes32 hash = _hashTypedDataV4(structHash);
        address signer = ECDSAUpgradeable.recover(hash, v, r, s);
        require(signer == owner, "ERC20Permit: invalid signature");
        _approve(owner, spender, value);
    }
    /**
     * @dev See {IERC20Permit-nonces}.
     */
    function nonces(address owner) public view virtual override returns (uint256) {
        return _nonces[owner].current();
    }
    /**
     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
        return _domainSeparatorV4();
    }
    /**
     * @dev "Consume a nonce": return the current value and increment.
     *
     * _Available since v4.1._
     */
    function _useNonce(address owner) internal virtual returns (uint256 current) {
        CountersUpgradeable.Counter storage nonce = _nonces[owner];
        current = nonce.current();
        nonce.increment();
    }
    /**
     * @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 v4.8.0) (access/Ownable2Step.sol)
pragma solidity ^0.8.0;
import "./OwnableUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
 * @dev Contract module which provides access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership} and {acceptOwnership}.
 *
 * This module is used through inheritance. It will make available all functions
 * from parent (Ownable).
 */
abstract contract Ownable2StepUpgradeable is Initializable, OwnableUpgradeable {
    function __Ownable2Step_init() internal onlyInitializing {
        __Ownable_init_unchained();
    }
    function __Ownable2Step_init_unchained() internal onlyInitializing {
    }
    address private _pendingOwner;
    event OwnershipTransferStarted(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Returns the address of the pending owner.
     */
    function pendingOwner() public view virtual returns (address) {
        return _pendingOwner;
    }
    /**
     * @dev Starts the ownership transfer of the contract to a new account. Replaces the pending transfer if there is one.
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual override onlyOwner {
        _pendingOwner = newOwner;
        emit OwnershipTransferStarted(owner(), newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`) and deletes any pending owner.
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual override {
        delete _pendingOwner;
        super._transferOwnership(newOwner);
    }
    /**
     * @dev The new owner accepts the ownership transfer.
     */
    function acceptOwnership() external {
        address sender = _msgSender();
        require(pendingOwner() == sender, "Ownable2Step: caller is not the new owner");
        _transferOwnership(sender);
    }
    /**
     * @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) (security/Pausable.sol)
pragma solidity ^0.8.0;
import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);
    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);
    bool private _paused;
    /**
     * @dev Initializes the contract in unpaused state.
     */
    function __Pausable_init() internal onlyInitializing {
        __Pausable_init_unchained();
    }
    function __Pausable_init_unchained() internal onlyInitializing {
        _paused = false;
    }
    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }
    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }
    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }
    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }
    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }
    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }
    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
    /**
     * @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 v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20PermitUpgradeable {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);
    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20Upgradeable.sol";
import "./extensions/IERC20MetadataUpgradeable.sol";
import "../../utils/ContextUpgradeable.sol";
import "../../proxy/utils/Initializable.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable, IERC20MetadataUpgradeable {
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    function __ERC20_init(string memory name_, string memory symbol_) internal onlyInitializing {
        __ERC20_init_unchained(name_, symbol_);
    }
    function __ERC20_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
        _name = name_;
        _symbol = symbol_;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }
        return true;
    }
    /**
     * @dev Moves `amount` of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(from, to, amount);
        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }
        emit Transfer(from, to, amount);
        _afterTokenTransfer(from, to, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);
        _afterTokenTransfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }
        emit Transfer(account, address(0), amount);
        _afterTokenTransfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[45] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../StringsUpgradeable.sol";
/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSAUpgradeable {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV // Deprecated in v4.8
    }
    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        }
    }
    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            /// @solidity memory-safe-assembly
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }
    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }
    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
     *
     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
     *
     * _Available since v4.3._
     */
    function tryRecover(
        bytes32 hash,
        bytes32 r,
        bytes32 vs
    ) internal pure returns (address, RecoverError) {
        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
        uint8 v = uint8((uint256(vs) >> 255) + 27);
        return tryRecover(hash, v, r, s);
    }
    /**
     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
     *
     * _Available since v4.2._
     */
    function recover(
        bytes32 hash,
        bytes32 r,
        bytes32 vs
    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }
    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
     * `r` and `s` signature fields separately.
     *
     * _Available since v4.3._
     */
    function tryRecover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }
        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }
        return (signer, RecoverError.NoError);
    }
    /**
     * @dev Overload of {ECDSA-recover} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }
    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
32", hash));
    }
    /**
     * @dev Returns an Ethereum Signed Message, created from `s`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
", StringsUpgradeable.toString(s.length), s));
    }
    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/EIP712.sol)
pragma solidity ^0.8.0;
import "./ECDSAUpgradeable.sol";
import "../../proxy/utils/Initializable.sol";
/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 *
 * @custom:storage-size 52
 */
abstract contract EIP712Upgradeable is Initializable {
    /* solhint-disable var-name-mixedcase */
    bytes32 private _HASHED_NAME;
    bytes32 private _HASHED_VERSION;
    bytes32 private constant _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
    /* solhint-enable var-name-mixedcase */
    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    function __EIP712_init(string memory name, string memory version) internal onlyInitializing {
        __EIP712_init_unchained(name, version);
    }
    function __EIP712_init_unchained(string memory name, string memory version) internal onlyInitializing {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
    }
    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        return _buildDomainSeparator(_TYPE_HASH, _EIP712NameHash(), _EIP712VersionHash());
    }
    function _buildDomainSeparator(
        bytes32 typeHash,
        bytes32 nameHash,
        bytes32 versionHash
    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }
    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return ECDSAUpgradeable.toTypedDataHash(_domainSeparatorV4(), structHash);
    }
    /**
     * @dev The hash of the name parameter for the EIP712 domain.
     *
     * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
     * are a concern.
     */
    function _EIP712NameHash() internal virtual view returns (bytes32) {
        return _HASHED_NAME;
    }
    /**
     * @dev The hash of the version parameter for the EIP712 domain.
     *
     * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
     * are a concern.
     */
    function _EIP712VersionHash() internal virtual view returns (bytes32) {
        return _HASHED_VERSION;
    }
    /**
     * @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 v4.4.1 (utils/Counters.sol)
pragma solidity ^0.8.0;
/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library CountersUpgradeable {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }
    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }
    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }
    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }
    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.1) (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.
     *
     * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
     * constructor.
     *
     * Emits an {Initialized} event.
     */
    modifier initializer() {
        bool isTopLevelCall = !_initializing;
        require(
            (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
            "Initializable: contract is already initialized"
        );
        _initialized = 1;
        if (isTopLevelCall) {
            _initializing = true;
        }
        _;
        if (isTopLevelCall) {
            _initializing = false;
            emit Initialized(1);
        }
    }
    /**
     * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
     * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
     * used to initialize parent contracts.
     *
     * A reinitializer may be used after the original initialization step. This is essential to configure modules that
     * are added through upgrades and that require initialization.
     *
     * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
     * cannot be nested. If one is invoked in the context of another, execution will revert.
     *
     * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
     * a contract, executing them in the right order is up to the developer or operator.
     *
     * WARNING: setting the version to 255 will prevent any future reinitialization.
     *
     * Emits an {Initialized} event.
     */
    modifier reinitializer(uint8 version) {
        require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
        _initialized = version;
        _initializing = true;
        _;
        _initializing = false;
        emit Initialized(version);
    }
    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} and {reinitializer} modifiers, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }
    /**
     * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
     * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
     * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
     * through proxies.
     *
     * Emits an {Initialized} event the first time it is successfully executed.
     */
    function _disableInitializers() internal virtual {
        require(!_initializing, "Initializable: contract is initializing");
        if (_initialized < type(uint8).max) {
            _initialized = type(uint8).max;
            emit Initialized(type(uint8).max);
        }
    }
    /**
     * @dev Returns the highest version that has been initialized. See {reinitializer}.
     */
    function _getInitializedVersion() internal view returns (uint8) {
        return _initialized;
    }
    /**
     * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
     */
    function _isInitializing() internal view returns (bool) {
        return _initializing;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal onlyInitializing {
        __Ownable_init_unchained();
    }
    function __Ownable_init_unchained() internal onlyInitializing {
        _transferOwnership(_msgSender());
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }
    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
    /**
     * @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 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 v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20Upgradeable {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20Upgradeable.sol";
/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20MetadataUpgradeable is IERC20Upgradeable {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);
    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);
    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)
pragma solidity ^0.8.0;
import "./math/MathUpgradeable.sol";
/**
 * @dev String operations.
 */
library StringsUpgradeable {
    bytes16 private constant _SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;
    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = MathUpgradeable.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }
    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, MathUpgradeable.log256(value) + 1);
        }
    }
    /**
     * @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] = _SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }
    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (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 functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)
pragma solidity ^0.8.0;
/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library MathUpgradeable {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }
    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }
    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }
    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }
    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }
    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(
        uint256 x,
        uint256 y,
        uint256 denominator
    ) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }
            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                return prod0 / denominator;
            }
            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1);
            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////
            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)
                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }
            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.
            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)
                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)
                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }
            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;
            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;
            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256
            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }
    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(
        uint256 x,
        uint256 y,
        uint256 denominator,
        Rounding rounding
    ) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }
    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);
        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }
    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }
    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }
    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }
    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10**64) {
                value /= 10**64;
                result += 64;
            }
            if (value >= 10**32) {
                value /= 10**32;
                result += 32;
            }
            if (value >= 10**16) {
                value /= 10**16;
                result += 16;
            }
            if (value >= 10**8) {
                value /= 10**8;
                result += 8;
            }
            if (value >= 10**4) {
                value /= 10**4;
                result += 4;
            }
            if (value >= 10**2) {
                value /= 10**2;
                result += 2;
            }
            if (value >= 10**1) {
                result += 1;
            }
        }
        return result;
    }
    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
        }
    }
    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }
    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
        }
    }
}