// File: /contracts/HyperDexRouter.sol



// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.0;
pragma experimental ABIEncoderV2;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@plasma-fi/contracts/utils/GasStationRecipient.sol";
import "@plasma-fi/contracts/interfaces/ITokensApprover.sol";
import "./interfaces/IHyperDex.sol";
import "./packages/LibBytesV06.sol";
import "./packages/LibProxyRichErrors.sol";
import "./packages/Ownable.sol";

/// @title Plasma Finance proxy contract for 0x proxy
/// @dev A generic proxy contract which extracts a fee before delegation
contract HyperDexRouter is GasStationRecipient, Ownable {
    using LibBytesV06 for bytes;
    using SafeERC20 for IERC20;
    using SafeMath for uint256;

    address private constant _ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address private constant _NULL_ADDRESS = 0x0000000000000000000000000000000000000000;

    address payable public beneficiary;
    address payable public allowanceTarget;
    IHyperDex public hyperDex;
    ITokensApprover public approver;

    uint256 public feeBeneficiary = 5; // 0.05%
    uint256[4] public feeReferrals = [4, 3, 2, 1];  // 0.05%, 0.03%, 0.02%, 0.01%

    mapping(bytes4 => address) private _implementationOverrides;

    event BeneficiaryChanged(address indexed beneficiary);
    event ImplementationOverrideSet(bytes4 indexed signature, address indexed implementation);
    event AllowanceTargetChanged(address indexed allowanceTarget);
    event HyperDexChanged(address indexed hyperDex);
    event TokensApproverChanged(address indexed approver);
    event FeePayment(address indexed recipient, address token, uint256 amount);

    /// @dev Construct this contract and specify a fee beneficiary, 0x proxy contract address, and allowance target
    constructor(IHyperDex _hyperDex, address payable _allowanceTarget, address payable _beneficiary, address _gasStation, ITokensApprover _approver) {
        hyperDex = _hyperDex;
        allowanceTarget = _allowanceTarget;
        beneficiary = _beneficiary;
        approver = _approver;

        _setGasStation(_gasStation);
    }

    /// @dev Fallback for just receiving ether.
    receive() external payable {}

    /// @dev Set a new MultiSwap proxy contract address
    /// @param _hyperDex New Exchange proxy address
    function setHyperDex(IHyperDex _hyperDex) public onlyOwner {
        require(address(_hyperDex) != _NULL_ADDRESS, "Invalid HyperDex address");
        hyperDex = _hyperDex;
        emit HyperDexChanged(address(hyperDex));
    }

    /// @dev Set a new new allowance target address
    /// @param _allowanceTarget New allowance target address
    function setAllowanceTarget(address payable _allowanceTarget) public onlyOwner {
        require(_allowanceTarget != _NULL_ADDRESS, "Invalid allowance target");
        allowanceTarget = _allowanceTarget;
        emit AllowanceTargetChanged(allowanceTarget);
    }

    /// @dev Set a new beneficiary address
    /// @param _beneficiary New beneficiary target address
    function setBeneficiary(address payable _beneficiary) public onlyOwner {
        require(_beneficiary != _NULL_ADDRESS, "Invalid beneficiary");
        beneficiary = _beneficiary;
        emit BeneficiaryChanged(beneficiary);
    }

    /// @dev Set a new trusted gas station address
    /// @param _gasStation New gas station address
    function setGasStation(address _gasStation) external onlyOwner {
        _setGasStation(_gasStation);
    }

    /// @dev Set a new tokens approver contract address
    /// @param _approver New approver address
    function setApprover(ITokensApprover _approver) external onlyOwner {
        require(address(_approver) != _NULL_ADDRESS, "Invalid beneficiary");
        approver = _approver;
        emit TokensApproverChanged(address(approver));
    }

    /// @dev Set a referrals fees
    /// @param _feeReferrals New referrals fees values
    function setFeeReferrals(uint256[4] memory _feeReferrals) public onlyOwner {
        feeReferrals = _feeReferrals;
    }

    /// @dev Set a beneficiary fees
    /// @param _feeBeneficiary New beneficiary fees value
    function setFeeBeneficiary(uint256 _feeBeneficiary) public onlyOwner {
        feeBeneficiary = _feeBeneficiary;
    }

    /// @dev Set a custom implementation feature
    /// @param signature function signature
    /// @param implementation address of the custom feature
    function setImplementationOverride(bytes4 signature, address implementation) public onlyOwner {
        _implementationOverrides[signature] = implementation;
        emit ImplementationOverrideSet(signature, implementation);
    }

    /// @dev Get function implementation address based on signature
    /// @param signature function signature
    /// @return impl address of implementation
    function getFunctionImplementation(bytes4 signature) public returns (address impl) {
        impl = _implementationOverrides[signature];
        if (impl == _NULL_ADDRESS) {
            impl = hyperDex.getFunctionImplementation(signature);
        }
    }

    /// @dev Forwards calls to the HyperDex contract and extracts a fee based on provided arguments
    /// @param msgData The byte data representing a swap using the original HyperDex contract. This is either recieved from the Multiswap API directly or we construct it in order to perform a single swap trade
    /// @param inputToken The ERC20 the user is selling. If this is ETH it should be the standard 0xeee ETH address
    /// @param inputAmount The amount of inputToken being sold, without fees
    /// @param outputToken The ERC20 the user is buying. If this is ETH it should be the standard 0xeee ETH address
    /// @param referrals Referral addresses for which interest will be accrued from each exchange.
    function multiRoute(
        bytes calldata msgData,
        address inputToken,
        uint256 inputAmount,
        address outputToken,
        address[4] memory referrals
    ) external payable returns (bytes memory) {
    return _multiRoute(msgData, inputToken, inputAmount, outputToken, referrals);
    }

    function multiRouteWithPermit(
        bytes calldata msgData,
        address inputToken,
        uint256 inputAmount,
        address outputToken,
        address[4] memory referrals,
        bytes calldata approvalData
    ) external payable returns (bytes memory) {
        _permit(inputToken, approvalData);
        return _multiRoute(msgData, inputToken, inputAmount, outputToken, referrals);
    }

    function _multiRoute(
        bytes calldata msgData,
        address inputToken,
        uint256 inputAmount,
        address outputToken,
        address[4] memory referrals
    ) internal returns (bytes memory) {
        // Calculate total fees and send to beneficiary.
        uint256 inputAmountPercent = inputAmount.div(10000);
        uint256 fee = inputAmountPercent.mul(feeBeneficiary);
        _payFees(inputToken, fee, beneficiary);
        for (uint256 i = 0; i < referrals.length; i++) {
            if (referrals[i] != _NULL_ADDRESS && feeReferrals[i] != 0) {
                uint256 feeReferral = inputAmountPercent.mul(feeReferrals[i]);
                fee = fee.add(feeReferral);
                _payFees(inputToken, feeReferral, payable(referrals[i]));
            }
        }

        // Checking the ETH balance and approve for token transfer
        uint256 value = 0;
        if (inputToken == _ETH_ADDRESS) {
            require(msg.value == inputAmount.add(fee), "Insufficient value with fee");
            value = inputAmount;
        } else {
            _sendERC20(IERC20(inputToken), _msgSender(), address(this), inputAmount);
            uint256 allowedAmount = IERC20(inputToken).allowance(address(this), allowanceTarget);
            if (allowedAmount < inputAmount) {
                IERC20(inputToken).safeIncreaseAllowance(allowanceTarget, inputAmount.sub(allowedAmount));
            }
        }

        // Call HyperDex multi swap
        (bool success, bytes memory resultData) = address(hyperDex).call{value : value}(msgData);

        if (!success) {
            _revertWithData(resultData);
        }

        // We send the received tokens back to the sender
        if (outputToken == _ETH_ADDRESS) {
            if (address(this).balance > 0) {
                _sendETH(payable(_msgSender()), address(this).balance);
            } else {
                _revertWithData(resultData);
            }
        } else {
            uint256 tokenBalance = IERC20(outputToken).balanceOf(address(this));
            if (tokenBalance > 0) {
                IERC20(outputToken).safeTransfer(_msgSender(), tokenBalance);
            } else {
                _revertWithData(resultData);
            }
        }
        _returnWithData(resultData);
    }

    function _permit(address token, bytes calldata approvalData) internal {
        if (approvalData.length > 0 && approver.hasConfigured(token)) {
            (bool success,) = approver.callPermit(token, approvalData);
            require(success, "Permit Method Call Error");
        }
    }

    /// @dev Pay fee to beneficiary
    /// @param token token address to pay fee in, can be ETH
    /// @param amount fee amount to pay
    function _payFees(address token, uint256 amount, address payable recipient) private {
        if (token == _ETH_ADDRESS) {
            _sendETH(recipient, amount);
        } else {
            _sendERC20(IERC20(token), _msgSender(), recipient, amount);
        }
        emit FeePayment(recipient, token, amount);
    }

    function _sendETH(address payable toAddress, uint256 amount) private {
        if (amount > 0) {
            (bool success,) = toAddress.call{value : amount}("");
            require(success, "Unable to send ETH");
        }
    }

    function _sendERC20(IERC20 token, address fromAddress, address toAddress, uint256 amount) private {
        if (amount > 0) {
            token.safeTransferFrom(fromAddress, toAddress, amount);
        }
    }

    /// @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))
        }
    }
}

// File: /contracts/packages/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () {
        address msgSender = _msgSenderContext();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSenderContext(), "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 {
        emit OwnershipTransferred(_owner, address(0));
        _owner = 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");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// File: /contracts/packages/LibRichErrorsV06.sol



// 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 ^0.8.0;


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))
        }
    }
}

// File: /contracts/packages/LibProxyRichErrors.sol



// 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 ^0.8.0;


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
        );
    }
}

// File: /contracts/packages/LibBytesV06.sol



// 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 ^0.8.0;

import "./LibBytesRichErrorsV06.sol";
import "./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)
        }
    }
}

// File: /contracts/packages/LibBytesRichErrorsV06.sol



// 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 ^0.8.0;


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
        );
    }
}

// File: /contracts/packages/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSenderContext() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgDataContext() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// File: /contracts/interfaces/IHyperDex.sol



// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.0;

interface IHyperDex {
    function getFunctionImplementation(bytes4 _signature) external returns (address);
}

// File: @plasma-fi/contracts/utils/GasStationRecipient.sol



//SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
pragma experimental ABIEncoderV2;

import "../interfaces/IGasStationRecipient.sol";

abstract contract GasStationRecipient is IGasStationRecipient {
    /*
     * Allowed Gas Station Contract for accept calls from
     */
    address private _gasStation;

    function isOwnGasStation(address addressToCheck) external view returns(bool) {
        return _gasStation == addressToCheck;
    }

    function gasStation() external view returns (address) {
        return _gasStation;
    }

    function _setGasStation(address newGasStation) internal {
        require(newGasStation != address(0), "Invalid new gas station address");
        _gasStation = newGasStation;
        emit GasStationChanged(_gasStation);
    }

    /**
    * return the sender of this call.
    * if the call came through our trusted forwarder, then the real sender is appended as the last 20 bytes
    * of the msg.data.
    * otherwise, return `msg.sender`
    * should be used in the contract anywhere instead of msg.sender
    */
    function _msgSender() internal view returns (address ret) {
        if (msg.data.length >= 20 && this.isOwnGasStation(msg.sender)) {
            // At this point we know that the sender is a trusted forwarder,
            // so we trust that the last bytes of msg.data are the verified sender address.
            // extract sender address from the end of msg.data
            assembly {
                ret := shr(96,calldataload(sub(calldatasize(),20)))
            }
        } else {
            ret = msg.sender;
        }
    }

    /**
     * return the msg.data of this call.
     * if the call came through our trusted forwarder, then the real sender was appended as the last 20 bytes
     * of the msg.data - so this method will strip those 20 bytes off.
     * otherwise (if the call was made directly and not through the forwarder), return `msg.data`
     * should be used in the contract instead of msg.data, where this difference matters.
     */
    function _msgData() internal view returns (bytes calldata ret) {
        if (msg.data.length >= 20 && this.isOwnGasStation(msg.sender)) {
            return msg.data[0:msg.data.length-20];
        } else {
            return msg.data;
        }
    }
}

// File: @plasma-fi/contracts/interfaces/ITokensApprover.sol



//SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
pragma experimental ABIEncoderV2;

interface ITokensApprover {
    /**
     * @notice Data for issuing permissions for the token
     */
    struct ApproveConfig {
        string name;
        string version;
        string domainType;
        string primaryType;
        string noncesMethod;
        string permitMethod;
        bytes4 permitMethodSelector;
    }

    function addConfig(ApproveConfig calldata config) external returns (uint256);

    function setConfig(uint256 id, ApproveConfig calldata config) external returns (uint256);

    function setToken(uint256 id, address token) external;

    function getConfig(address token) view external returns (ApproveConfig memory);

    function getConfigById(uint256 id) view external returns (ApproveConfig memory);

    function configsLength() view external returns (uint256);

    function hasConfigured(address token) view external returns (bool);

    function callPermit(address token, bytes calldata permitCallData) external returns (bool, bytes memory);
}

// File: @plasma-fi/contracts/interfaces/IGasStationRecipient.sol



//SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
pragma experimental ABIEncoderV2;

interface IGasStationRecipient {

    event GasStationChanged(address indexed gasStation);

    function isOwnGasStation(address addressToCheck) external view returns(bool);
}

// File: @openzeppelin/contracts/utils/math/SafeMath.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)

pragma solidity ^0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../../../utils/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}