// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library 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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

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

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

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

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

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

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT
pragma solidity 0.8.x;

library Consts {
    address public constant MULTICALL_ADDRESS = 0xcA11bde05977b3631167028862bE2a173976CA11;
    address public constant PERMIT2_ADDRESS = 0x000000000022D473030F116dDEE9F6B43aC78BA3;
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {OrderInfo} from "../base/ReactorStructs.sol";
import {OrderInfoLib} from "./OrderInfoLib.sol";
import {ERC20} from "solmate/src/tokens/ERC20.sol";

/// @dev An amount of output tokens that decreases linearly over time
struct DutchOutput {
    // The ERC20 token address (or native ETH address)
    address token;
    // The amount of tokens at the start of the time period
    uint256 startAmount;
    // The amount of tokens at the end of the time period
    uint256 endAmount;
    // The address who must receive the tokens to satisfy the order
    address recipient;
}

/// @dev An amount of input tokens that increases linearly over time
struct DutchInput {
    // The ERC20 token address
    ERC20 token;
    // The amount of tokens at the start of the time period
    uint256 startAmount;
    // The amount of tokens at the end of the time period
    uint256 endAmount;
}

struct DutchOrder {
    // generic order information
    OrderInfo info;
    // The time at which the DutchOutputs start decaying
    uint256 decayStartTime;
    // The time at which price becomes static
    uint256 decayEndTime;
    // The tokens that the swapper will provide when settling the order
    DutchInput input;
    // The tokens that must be received to satisfy the order
    DutchOutput[] outputs;
}

/// @notice helpers for handling dutch order objects
library DutchOrderLib {
    using OrderInfoLib for OrderInfo;

    bytes internal constant DUTCH_OUTPUT_TYPE =
        "DutchOutput(address token,uint256 startAmount,uint256 endAmount,address recipient)";
    bytes32 internal constant DUTCH_OUTPUT_TYPE_HASH = keccak256(DUTCH_OUTPUT_TYPE);

    bytes internal constant DUTCH_LIMIT_ORDER_TYPE = abi.encodePacked(
        "DutchOrder(",
        "OrderInfo info,",
        "uint256 decayStartTime,",
        "uint256 decayEndTime,",
        "address inputToken,",
        "uint256 inputStartAmount,",
        "uint256 inputEndAmount,",
        "DutchOutput[] outputs)"
    );

    /// @dev Note that sub-structs have to be defined in alphabetical order in the EIP-712 spec
    bytes internal constant ORDER_TYPE =
        abi.encodePacked(DUTCH_LIMIT_ORDER_TYPE, DUTCH_OUTPUT_TYPE, OrderInfoLib.ORDER_INFO_TYPE);
    bytes32 internal constant ORDER_TYPE_HASH = keccak256(ORDER_TYPE);

    string internal constant TOKEN_PERMISSIONS_TYPE = "TokenPermissions(address token,uint256 amount)";
    string internal constant PERMIT2_ORDER_TYPE =
        string(abi.encodePacked("DutchOrder witness)", ORDER_TYPE, TOKEN_PERMISSIONS_TYPE));

    /// @notice hash the given output
    /// @param output the output to hash
    /// @return the eip-712 output hash
    function hash(DutchOutput memory output) internal pure returns (bytes32) {
        return keccak256(
            abi.encode(DUTCH_OUTPUT_TYPE_HASH, output.token, output.startAmount, output.endAmount, output.recipient)
        );
    }

    /// @notice hash the given outputs
    /// @param outputs the outputs to hash
    /// @return the eip-712 outputs hash
    function hash(DutchOutput[] memory outputs) internal pure returns (bytes32) {
        unchecked {
            bytes memory packedHashes = new bytes(32 * outputs.length);

            for (uint256 i = 0; i < outputs.length; i++) {
                bytes32 outputHash = hash(outputs[i]);
                assembly {
                    mstore(add(add(packedHashes, 0x20), mul(i, 0x20)), outputHash)
                }
            }

            return keccak256(packedHashes);
        }
    }

    /// @notice hash the given order
    /// @param order the order to hash
    /// @return the eip-712 order hash
    function hash(DutchOrder memory order) internal pure returns (bytes32) {
        return keccak256(
            abi.encode(
                ORDER_TYPE_HASH,
                order.info.hash(),
                order.decayStartTime,
                order.decayEndTime,
                order.input.token,
                order.input.startAmount,
                order.input.endAmount,
                hash(order.outputs)
            )
        );
    }
}

// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 amount);

    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    uint8 public immutable decimals;

    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 public totalSupply;

    mapping(address => uint256) public balanceOf;

    mapping(address => mapping(address => uint256)) public allowance;

    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 internal immutable INITIAL_CHAIN_ID;

    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;

    mapping(address => uint256) public nonces;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

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

        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }

    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;

        emit Approval(msg.sender, spender, amount);

        return true;
    }

    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(msg.sender, to, amount);

        return true;
    }

    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.

        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;

        balanceOf[from] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(from, to, amount);

        return true;
    }

    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");

        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\x19\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );

            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");

            allowance[recoveredAddress][spender] = value;
        }

        emit Approval(owner, spender, value);
    }

    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }

    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;

        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }

        emit Transfer(from, address(0), amount);
    }
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {OrderInfo} from "../base/ReactorStructs.sol";
import {DutchOutput, DutchInput, DutchOrderLib} from "./DutchOrderLib.sol";
import {OrderInfoLib} from "./OrderInfoLib.sol";

struct ExclusiveDutchOrder {
    // generic order information
    OrderInfo info;
    // The time at which the DutchOutputs start decaying
    uint256 decayStartTime;
    // The time at which price becomes static
    uint256 decayEndTime;
    // The address who has exclusive rights to the order until decayStartTime
    address exclusiveFiller;
    // The amount in bps that a non-exclusive filler needs to improve the outputs by to be able to fill the order
    uint256 exclusivityOverrideBps;
    // The tokens that the swapper will provide when settling the order
    DutchInput input;
    // The tokens that must be received to satisfy the order
    DutchOutput[] outputs;
}

/// @notice helpers for handling dutch order objects
library ExclusiveDutchOrderLib {
    using DutchOrderLib for DutchOutput[];
    using OrderInfoLib for OrderInfo;

    bytes internal constant EXCLUSIVE_DUTCH_LIMIT_ORDER_TYPE = abi.encodePacked(
        "ExclusiveDutchOrder(",
        "OrderInfo info,",
        "uint256 decayStartTime,",
        "uint256 decayEndTime,",
        "address exclusiveFiller,",
        "uint256 exclusivityOverrideBps,",
        "address inputToken,",
        "uint256 inputStartAmount,",
        "uint256 inputEndAmount,",
        "DutchOutput[] outputs)"
    );

    bytes internal constant ORDER_TYPE = abi.encodePacked(
        EXCLUSIVE_DUTCH_LIMIT_ORDER_TYPE, DutchOrderLib.DUTCH_OUTPUT_TYPE, OrderInfoLib.ORDER_INFO_TYPE
    );
    bytes32 internal constant ORDER_TYPE_HASH = keccak256(ORDER_TYPE);

    /// @dev Note that sub-structs have to be defined in alphabetical order in the EIP-712 spec
    string internal constant PERMIT2_ORDER_TYPE = string(
        abi.encodePacked(
            "ExclusiveDutchOrder witness)",
            DutchOrderLib.DUTCH_OUTPUT_TYPE,
            EXCLUSIVE_DUTCH_LIMIT_ORDER_TYPE,
            OrderInfoLib.ORDER_INFO_TYPE,
            DutchOrderLib.TOKEN_PERMISSIONS_TYPE
        )
    );

    /// @notice hash the given order
    /// @param order the order to hash
    /// @return the eip-712 order hash
    function hash(ExclusiveDutchOrder memory order) internal pure returns (bytes32) {
        return keccak256(
            abi.encode(
                ORDER_TYPE_HASH,
                order.info.hash(),
                order.decayStartTime,
                order.decayEndTime,
                order.exclusiveFiller,
                order.exclusivityOverrideBps,
                order.input.token,
                order.input.startAmount,
                order.input.endAmount,
                order.outputs.hash()
            )
        );
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

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

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.9.0;

pragma experimental ABIEncoderV2;

interface IMulticall3 {
    struct Call {
        address target;
        bytes callData;
    }

    struct Call3 {
        address target;
        bool allowFailure;
        bytes callData;
    }

    struct Call3Value {
        address target;
        bool allowFailure;
        uint256 value;
        bytes callData;
    }

    struct Result {
        bool success;
        bytes returnData;
    }

    function aggregate(Call[] calldata calls)
        external
        payable
        returns (uint256 blockNumber, bytes[] memory returnData);

    function aggregate3(Call3[] calldata calls) external payable returns (Result[] memory returnData);

    function aggregate3Value(Call3Value[] calldata calls) external payable returns (Result[] memory returnData);

    function blockAndAggregate(Call[] calldata calls)
        external
        payable
        returns (uint256 blockNumber, bytes32 blockHash, Result[] memory returnData);

    function getBasefee() external view returns (uint256 basefee);

    function getBlockHash(uint256 blockNumber) external view returns (bytes32 blockHash);

    function getBlockNumber() external view returns (uint256 blockNumber);

    function getChainId() external view returns (uint256 chainid);

    function getCurrentBlockCoinbase() external view returns (address coinbase);

    function getCurrentBlockDifficulty() external view returns (uint256 difficulty);

    function getCurrentBlockGasLimit() external view returns (uint256 gaslimit);

    function getCurrentBlockTimestamp() external view returns (uint256 timestamp);

    function getEthBalance(address addr) external view returns (uint256 balance);

    function getLastBlockHash() external view returns (bytes32 blockHash);

    function tryAggregate(bool requireSuccess, Call[] calldata calls)
        external
        payable
        returns (Result[] memory returnData);

    function tryBlockAndAggregate(bool requireSuccess, Call[] calldata calls)
        external
        payable
        returns (uint256 blockNumber, bytes32 blockHash, Result[] memory returnData);
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {ResolvedOrder, SignedOrder} from "../base/ReactorStructs.sol";
import {IReactorCallback} from "./IReactorCallback.sol";

/// @notice Interface for order execution reactors
interface IReactor {
    /// @notice Execute a single order
    /// @param order The order definition and valid signature to execute
    function execute(SignedOrder calldata order) external payable;

    /// @notice Execute a single order using the given callback data
    /// @param order The order definition and valid signature to execute
    function executeWithCallback(SignedOrder calldata order, bytes calldata callbackData) external payable;

    /// @notice Execute the given orders at once
    /// @param orders The order definitions and valid signatures to execute
    function executeBatch(SignedOrder[] calldata orders) external payable;

    /// @notice Execute the given orders at once using a callback with the given callback data
    /// @param orders The order definitions and valid signatures to execute
    /// @param callbackData The callbackData to pass to the callback
    function executeBatchWithCallback(SignedOrder[] calldata orders, bytes calldata callbackData) external payable;
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {ResolvedOrder} from "../base/ReactorStructs.sol";

/// @notice Callback for executing orders through a reactor.
interface IReactorCallback {
    /// @notice Called by the reactor during the execution of an order
    /// @param resolvedOrders Has inputs and outputs
    /// @param callbackData The callbackData specified for an order execution
    /// @dev Must have approved each token and amount in outputs to the msg.sender
    function reactorCallback(ResolvedOrder[] memory resolvedOrders, bytes memory callbackData) external;
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {OrderInfo, ResolvedOrder} from "../base/ReactorStructs.sol";

/// @notice Callback to validate an order
interface IValidationCallback {
    /// @notice Called by the reactor for custom validation of an order. Will revert if validation fails
    /// @param filler The filler of the order
    /// @param resolvedOrder The resolved order to fill
    function validate(address filler, ResolvedOrder calldata resolvedOrder) external view;
}

// SPDX-License-Identifier: MIT
pragma solidity 0.8.x;

import {IMulticall3} from "forge-std/interfaces/IMulticall3.sol";

import {Address} from "@openzeppelin/contracts/utils/Address.sol";
import {SafeERC20, IERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

import {IReactor} from "uniswapx/src/interfaces/IReactor.sol";
import {IReactorCallback} from "uniswapx/src/interfaces/IReactorCallback.sol";
import {IValidationCallback} from "uniswapx/src/interfaces/IValidationCallback.sol";
import {ResolvedOrder, SignedOrder} from "uniswapx/src/base/ReactorStructs.sol";
import {ExclusiveDutchOrder} from "uniswapx/src/lib/ExclusiveDutchOrderLib.sol";

import {Consts} from "./Consts.sol";

/**
 * LiquidityHub Executor
 */
contract LiquidityHub is IReactorCallback, IValidationCallback {
    using SafeERC20 for IERC20;

    error InvalidSender(address sender);
    error InvalidOrder();

    event Resolved(
        bytes32 indexed orderHash,
        address indexed swapper,
        address indexed ref,
        address inToken,
        address outToken,
        uint256 inAmount,
        uint256 outAmount
    );

    event ExtraOut(address indexed recipient, address token, uint256 amount);

    event Surplus(address indexed ref, address swapper, address token, uint256 amount, uint256 refshare);

    uint8 public constant VERSION = 6;
    address public constant INVALID_ADDRESS = address(1);

    IReactor public immutable reactor;
    IAllowed public immutable allowed;

    constructor(IReactor _reactor, IAllowed _allowed) {
        reactor = _reactor;
        allowed = _allowed;
    }

    modifier onlyAllowed() {
        if (!allowed.allowed(msg.sender)) revert InvalidSender(msg.sender);
        _;
    }

    modifier onlyReactor() {
        if (msg.sender != address(reactor)) revert InvalidSender(msg.sender);
        _;
    }

    /**
     * Entry point
     */
    function execute(SignedOrder calldata order, IMulticall3.Call[] calldata calls, uint256 outAmountSwapper)
        external
        onlyAllowed
    {
        reactor.executeWithCallback(order, abi.encode(calls, outAmountSwapper));

        ExclusiveDutchOrder memory o = abi.decode(order.order, (ExclusiveDutchOrder));
        (address ref, uint8 share) = abi.decode(o.info.additionalValidationData, (address, uint8));

        _surplus(ref, o.info.swapper, address(o.input.token), share);
        for (uint256 i = 0; i < o.outputs.length; i++) {
            _surplus(ref, o.info.swapper, address(o.outputs[i].token), share);
        }
    }

    /**
     * @dev IReactorCallback
     */
    function reactorCallback(ResolvedOrder[] memory orders, bytes memory callbackData) external override onlyReactor {
        ResolvedOrder memory order = orders[0];

        (IMulticall3.Call[] memory calls, uint256 outAmountSwapper) =
            abi.decode(callbackData, (IMulticall3.Call[], uint256));

        _executeMulticall(calls);

        (address outToken, uint256 outAmount) = _handleOrderOutputs(order);
        if (outAmountSwapper > outAmount) _transfer(outToken, order.info.swapper, outAmountSwapper - outAmount);

        address ref = abi.decode(order.info.additionalValidationData, (address));

        emit Resolved(
            order.hash, order.info.swapper, ref, address(order.input.token), outToken, order.input.amount, outAmount
        );
    }

    function _executeMulticall(IMulticall3.Call[] memory calls) private {
        Address.functionDelegateCall(
            Consts.MULTICALL_ADDRESS, abi.encodeWithSelector(IMulticall3.aggregate.selector, calls)
        );
    }

    function _handleOrderOutputs(ResolvedOrder memory order) private returns (address outToken, uint256 outAmount) {
        outToken = INVALID_ADDRESS;
        for (uint256 i = 0; i < order.outputs.length; i++) {
            uint256 amount = order.outputs[i].amount;

            if (amount > 0) {
                address token = address(order.outputs[i].token);
                _outputReactor(token, amount);

                if (order.outputs[i].recipient == order.info.swapper) {
                    if (outToken != INVALID_ADDRESS && outToken != token) revert InvalidOrder();
                    outToken = token;
                    outAmount += amount;
                } else {
                    emit ExtraOut(order.outputs[i].recipient, token, amount);
                }
            }
        }
    }

    function _surplus(address ref, address swapper, address token, uint8 share) private {
        uint256 balance = _balanceOf(token, address(this));
        if (balance == 0) return;

        uint256 refshare = (ref != address(0)) ? balance * share / 100 : 0;

        if (refshare > 0) _transfer(token, ref, refshare);
        _transfer(token, swapper, balance - refshare);

        emit Surplus(ref, swapper, token, balance, refshare);
    }

    function _outputReactor(address token, uint256 amount) private {
        if (token == address(0)) {
            Address.sendValue(payable(address(reactor)), amount);
        } else {
            uint256 allowance = IERC20(token).allowance(address(this), address(reactor));
            IERC20(token).safeApprove(address(reactor), 0);
            IERC20(token).safeApprove(address(reactor), allowance + amount);
        }
    }

    function _transfer(address token, address to, uint256 amount) private {
        if (token == address(0)) Address.sendValue(payable(to), amount);
        else IERC20(token).safeTransfer(to, amount);
    }

    function _balanceOf(address token, address who) private view returns (uint256) {
        return (token == address(0)) ? who.balance : IERC20(token).balanceOf(who);
    }

    /**
     * @dev IValidationCallback
     */
    function validate(address filler, ResolvedOrder calldata) external view override {
        if (filler != address(this)) revert InvalidSender(filler);
    }

    receive() external payable {
        // accept ETH
    }
}

interface IAllowed {
    function allowed(address) external view returns (bool);
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {OrderInfo} from "../base/ReactorStructs.sol";

/// @notice helpers for handling OrderInfo objects
library OrderInfoLib {
    bytes internal constant ORDER_INFO_TYPE =
        "OrderInfo(address reactor,address swapper,uint256 nonce,uint256 deadline,address additionalValidationContract,bytes additionalValidationData)";
    bytes32 internal constant ORDER_INFO_TYPE_HASH = keccak256(ORDER_INFO_TYPE);

    /// @notice hash an OrderInfo object
    /// @param info The OrderInfo object to hash
    function hash(OrderInfo memory info) internal pure returns (bytes32) {
        return keccak256(
            abi.encode(
                ORDER_INFO_TYPE_HASH,
                info.reactor,
                info.swapper,
                info.nonce,
                info.deadline,
                info.additionalValidationContract,
                keccak256(info.additionalValidationData)
            )
        );
    }
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;

import {IReactor} from "../interfaces/IReactor.sol";
import {IValidationCallback} from "../interfaces/IValidationCallback.sol";
import {ERC20} from "solmate/src/tokens/ERC20.sol";

/// @dev generic order information
///  should be included as the first field in any concrete order types
struct OrderInfo {
    // The address of the reactor that this order is targeting
    // Note that this must be included in every order so the swapper
    // signature commits to the specific reactor that they trust to fill their order properly
    IReactor reactor;
    // The address of the user which created the order
    // Note that this must be included so that order hashes are unique by swapper
    address swapper;
    // The nonce of the order, allowing for signature replay protection and cancellation
    uint256 nonce;
    // The timestamp after which this order is no longer valid
    uint256 deadline;
    // Custom validation contract
    IValidationCallback additionalValidationContract;
    // Encoded validation params for additionalValidationContract
    bytes additionalValidationData;
}

/// @dev tokens that need to be sent from the swapper in order to satisfy an order
struct InputToken {
    ERC20 token;
    uint256 amount;
    // Needed for dutch decaying inputs
    uint256 maxAmount;
}

/// @dev tokens that need to be received by the recipient in order to satisfy an order
struct OutputToken {
    address token;
    uint256 amount;
    address recipient;
}

/// @dev generic concrete order that specifies exact tokens which need to be sent and received
struct ResolvedOrder {
    OrderInfo info;
    InputToken input;
    OutputToken[] outputs;
    bytes sig;
    bytes32 hash;
}

/// @dev external struct including a generic encoded order and swapper signature
///  The order bytes will be parsed and mapped to a ResolvedOrder in the concrete reactor contract
struct SignedOrder {
    bytes order;
    bytes sig;
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/IERC20Permit.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;

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    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));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    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");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @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");
        require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
    }

    /**
     * @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).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // 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 cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}

{
  "compilationTarget": {
    "src/LiquidityHub.sol": "LiquidityHub"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 1000000
  },
  "remappings": [
    ":@openzeppelin/contracts/=lib/openzeppelin-contracts/contracts/",
    ":UniswapX/=lib/UniswapX/",
    ":ds-test/=lib/forge-std/lib/ds-test/src/",
    ":erc4626-tests/=lib/openzeppelin-contracts/lib/erc4626-tests/",
    ":forge-gas-snapshot/=lib/UniswapX/lib/forge-gas-snapshot/src/",
    ":forge-std/=lib/forge-std/src/",
    ":openzeppelin-contracts/=lib/openzeppelin-contracts/contracts/",
    ":openzeppelin/=lib/openzeppelin-contracts/contracts/",
    ":permit2/=lib/UniswapX/lib/permit2/",
    ":solmate/=lib/solmate/",
    ":uniswapx/=lib/UniswapX/"
  ]
}