// SPDX-License-Identifier: MIT
// File: @openzeppelin/contracts/utils/Address.sol
pragma solidity ^0.6.2;
/**
 * @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 in extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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");
        return _functionCallWithValue(target, data, value, errorMessage);
    }
    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        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
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// File: contracts/upgrade_proxy/Proxy.sol
pragma solidity ^0.6.0;
/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 * 
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 * 
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     * 
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())
            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())
            switch result
            // delegatecall returns 0 on error.
            case 0 { revert(0, returndatasize()) }
            default { return(0, returndatasize()) }
        }
    }
    /**
     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal virtual view returns (address);
    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     * 
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _fallback() internal {
        _beforeFallback();
        _delegate(_implementation());
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback () payable external {
        _fallback();
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive () payable external {
        _fallback();
    }
    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     * 
     * If overriden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {
    }
}
// File: contracts/upgrade_proxy/UpgradeableProxy.sol
pragma solidity ^0.6.0;
/**
 * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
 * implementation address that can be changed. This address is stored in storage in the location specified by
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
 * implementation behind the proxy.
 * 
 * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
 * {TransparentUpgradeableProxy}.
 */
contract UpgradeableProxy is Proxy {
    /**
     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
     * 
     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
     * function call, and allows initializating the storage of the proxy like a Solidity constructor.
     */
    constructor(address _logic, bytes memory _data) public payable {
        assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
        _setImplementation(_logic);
        if(_data.length > 0) {
            // solhint-disable-next-line avoid-low-level-calls
            (bool success,) = _logic.delegatecall(_data);
            require(success);
        }
    }
    /**
     * @dev Emitted when the implementation is upgraded.
     */
    event Upgraded(address indexed implementation);
    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
    /**
     * @dev Returns the current implementation address.
     */
    function _implementation() internal override view returns (address impl) {
        bytes32 slot = _IMPLEMENTATION_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            impl := sload(slot)
        }
    }
    /**
     * @dev Upgrades the proxy to a new implementation.
     * 
     * Emits an {Upgraded} event.
     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }
    /**
     * @dev Stores a new address in the EIP1967 implementation slot.
     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
        bytes32 slot = _IMPLEMENTATION_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            sstore(slot, newImplementation)
        }
    }
}
// File: contracts/upgrade_proxy/TransparentUpgradeableProxy.sol
pragma solidity ^0.6.0;
/**
 * @dev This contract implements a proxy that is upgradeable by an admin.
 * 
 * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
 * clashing], which can potentially be used in an attack, this contract uses the
 * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
 * things that go hand in hand:
 * 
 * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
 * that call matches one of the admin functions exposed by the proxy itself.
 * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
 * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
 * "admin cannot fallback to proxy target".
 * 
 * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
 * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
 * to sudden errors when trying to call a function from the proxy implementation.
 * 
 * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
 * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
 */
contract TransparentUpgradeableProxy is UpgradeableProxy {
    /**
     * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
     * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
     */
    constructor(address _logic, address _admin, bytes memory _data) public payable UpgradeableProxy(_logic, _data) {
        assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
        _setAdmin(_admin);
    }
    /**
     * @dev Emitted when the admin account has changed.
     */
    event AdminChanged(address previousAdmin, address newAdmin);
    /**
     * @dev Storage slot with the admin of the contract.
     * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
    /**
     * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
     */
    modifier ifAdmin() {
        if (msg.sender == _admin()) {
            _;
        } else {
            _fallback();
        }
    }
    /**
     * @dev Returns the current admin.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
     * 
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
     */
    function admin() external ifAdmin returns (address) {
        return _admin();
    }
    /**
     * @dev Returns the current implementation.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
     * 
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
     */
    function implementation() external ifAdmin returns (address) {
        return _implementation();
    }
    /**
     * @dev Changes the admin of the proxy.
     * 
     * Emits an {AdminChanged} event.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
     */
    function changeAdmin(address newAdmin) external ifAdmin {
        require(newAdmin != address(0), "TransparentUpgradeableProxy: new admin is the zero address");
        emit AdminChanged(_admin(), newAdmin);
        _setAdmin(newAdmin);
    }
    /**
     * @dev Upgrade the implementation of the proxy.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
     */
    function upgradeTo(address newImplementation) external ifAdmin {
        _upgradeTo(newImplementation);
    }
    /**
     * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
     * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
     * proxied contract.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
     */
    function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
        _upgradeTo(newImplementation);
        // solhint-disable-next-line avoid-low-level-calls
        (bool success,) = newImplementation.delegatecall(data);
        require(success);
    }
    /**
     * @dev Returns the current admin.
     */
    function _admin() internal view returns (address adm) {
        bytes32 slot = _ADMIN_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            adm := sload(slot)
        }
    }
    /**
     * @dev Stores a new address in the EIP1967 admin slot.
     */
    function _setAdmin(address newAdmin) private {
        bytes32 slot = _ADMIN_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            sstore(slot, newAdmin)
        }
    }
    /**
     * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
     */
    function _beforeFallback() internal override virtual {
        require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
        super._beforeFallback();
    }
}
// File: contracts/Tokenlon.sol
pragma solidity ^0.6.0;
contract Tokenlon is TransparentUpgradeableProxy {
    constructor(address _logic, address _admin, bytes memory _data) public payable TransparentUpgradeableProxy(_logic, _admin, _data) {}
}

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

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

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

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

pragma solidity ^0.4.18;

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

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

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

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

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

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

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

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

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

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

        Transfer(src, dst, wad);

        return true;
    }
}


/*
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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

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

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

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

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

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

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

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

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

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

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

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

*/

// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0;
interface IWETH {
    function balanceOf(address account) external view returns (uint256);
    function deposit() external payable;
    function withdraw(uint256 amount) external;
    function transfer(address dst, uint256 wad) external returns (bool);
    function transferFrom(
        address src,
        address dst,
        uint256 wad
    ) external returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/cryptography/ECDSA.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "./interfaces/IWETH.sol";
import "./utils/LibConstant.sol";
import "./utils/Ownable.sol";
contract MarketMakerProxy is Ownable {
    using SafeERC20 for IERC20;
    using Address for address payable;
    event ChangeSigner(address newSigner);
    event UpdateWhitelist(address addr, bool enabled);
    event WrapETH(uint256 amount);
    event WithdrawETH(uint256 amount);
    // bytes4(keccak256("isValidSignature(bytes32,bytes)")
    bytes4 public constant EIP1271_MAGICVALUE = 0x1626ba7e;
    IWETH public immutable WETH;
    address public signer;
    mapping(address => bool) public isWithdrawWhitelist;
    constructor(
        address _owner,
        address _signer,
        IWETH _weth
    ) Ownable(_owner) {
        require(_signer != address(0), "MarketMakerProxy: zero address");
        signer = _signer;
        WETH = _weth;
    }
    receive() external payable {}
    function setSigner(address _signer) external onlyOwner {
        require(_signer != address(0), "MarketMakerProxy: zero address");
        emit ChangeSigner(_signer);
        signer = _signer;
    }
    function setAllowance(address[] calldata tokenAddrs, address spender) external onlyOwner {
        for (uint256 i = 0; i < tokenAddrs.length; i++) {
            IERC20(tokenAddrs[i]).safeApprove(spender, LibConstant.MAX_UINT);
        }
    }
    function closeAllowance(address[] calldata tokenAddrs, address spender) external onlyOwner {
        for (uint256 i = 0; i < tokenAddrs.length; ++i) {
            IERC20(tokenAddrs[i]).safeApprove(spender, 0);
        }
    }
    function updateWithdrawWhitelist(address _addr, bool _enabled) external onlyOwner {
        require(_addr != address(0), "MarketMakerProxy: zero address");
        isWithdrawWhitelist[_addr] = _enabled;
        emit UpdateWhitelist(_addr, _enabled);
    }
    function wrapETH() external onlyOwner {
        uint256 balance = address(this).balance;
        if (balance > 0) {
            WETH.deposit{ value: balance }();
            emit WrapETH(balance);
        }
    }
    function withdrawToken(
        address token,
        address to,
        uint256 amount
    ) external onlyOwner {
        require(isWithdrawWhitelist[to], "MarketMakerProxy: not in withdraw whitelist");
        IERC20(token).safeTransfer(to, amount);
    }
    function withdrawETH(address payable to, uint256 amount) external onlyOwner {
        require(isWithdrawWhitelist[to], "MarketMakerProxy: not in withdraw whitelist");
        to.sendValue(amount);
        emit WithdrawETH(amount);
    }
    function isValidSignature(bytes32 dataHash, bytes calldata signature) external view returns (bytes4) {
        require(signer == ECDSA.recover(dataHash, signature), "MarketMakerProxy: invalid signature");
        return EIP1271_MAGICVALUE;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.6;
library LibConstant {
    int256 internal constant MAX_INT = 2**255 - 1;
    uint256 internal constant MAX_UINT = 2**256 - 1;
    uint16 internal constant BPS_MAX = 10000;
    address internal constant ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address internal constant ZERO_ADDRESS = address(0);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.6;
/// @title Ownable Contract
/// @author imToken Labs
abstract contract Ownable {
    address public owner;
    address public nominatedOwner;
    event OwnerNominated(address indexed newOwner);
    event OwnerChanged(address indexed oldOwner, address indexed newOwner);
    constructor(address _owner) {
        require(_owner != address(0), "owner should not be 0");
        owner = _owner;
    }
    modifier onlyOwner() {
        require(msg.sender == owner, "not owner");
        _;
    }
    /// @notice Activate new ownership
    /// @notice Only nominated owner can call
    function acceptOwnership() external {
        require(msg.sender == nominatedOwner, "not nominated");
        emit OwnerChanged(owner, nominatedOwner);
        owner = nominatedOwner;
        nominatedOwner = address(0);
    }
    /// @notice Give up the ownership
    /// @notice Only owner can call
    /// @notice Ownership cannot be recovered
    function renounceOwnership() external onlyOwner {
        require(nominatedOwner == address(0), "pending nomination exists");
        emit OwnerChanged(owner, address(0));
        owner = address(0);
    }
    /// @notice Nominate new owner
    /// @notice Only owner can call
    /// @param newOwner The address of the new owner
    function nominateNewOwner(address newOwner) external onlyOwner {
        nominatedOwner = newOwner;
        emit OwnerNominated(newOwner);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        // Check the signature length
        if (signature.length != 65) {
            revert("ECDSA: invalid signature length");
        }
        // Divide the signature in r, s and v variables
        bytes32 r;
        bytes32 s;
        uint8 v;
        // ecrecover takes the signature parameters, and the only way to get them
        // currently is to use assembly.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }
        return recover(hash, v, r, s);
    }
    /**
     * @dev Overload of {ECDSA-recover-bytes32-bytes-} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        require(uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0, "ECDSA: invalid signature 's' value");
        require(v == 27 || v == 28, "ECDSA: invalid signature 'v' value");
        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        require(signer != address(0), "ECDSA: invalid signature");
        return signer;
    }
    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * replicates the behavior of the
     * https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sign[`eth_sign`]
     * JSON-RPC method.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
32", hash));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        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) {
        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) {
        // 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) {
        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) {
        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) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        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) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @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. 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) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        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) {
        require(b > 0, "SafeMath: modulo by zero");
        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) {
        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.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * 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) {
        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) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    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'
        // solhint-disable-next-line max-line-length
        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).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _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
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @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;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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");
        // solhint-disable-next-line avoid-low-level-calls
        (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");
        // solhint-disable-next-line avoid-low-level-calls
        (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");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

pragma solidity ^0.6.0;
pragma experimental ABIEncoderV2;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "./interfaces/ISpender.sol";
import "./interfaces/IWeth.sol";
import "./interfaces/IRFQ.sol";
import "./interfaces/IPermanentStorage.sol";
import "./interfaces/IERC1271Wallet.sol";
import "./utils/RFQLibEIP712.sol";
contract RFQ is
    ReentrancyGuard,
    IRFQ,
    RFQLibEIP712,
    SignatureValidator
{
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    using Address for address;
    // Constants do not have storage slot.
    string public constant version = "5.2.0";
    uint256 private constant MAX_UINT = 2**256 - 1;
    string public constant SOURCE = "RFQ v1";
    uint256 private constant BPS_MAX = 10000;
    address public immutable userProxy;
    IPermanentStorage public immutable permStorage;
    IWETH public immutable weth;
    // Below are the variables which consume storage slots.
    address public operator;
    ISpender public spender;
    struct GroupedVars {
        bytes32 orderHash;
        bytes32 transactionHash;
    }
    // Operator events
    event TransferOwnership(address newOperator);
    event UpgradeSpender(address newSpender);
    event AllowTransfer(address spender);
    event DisallowTransfer(address spender);
    event DepositETH(uint256 ethBalance);
    event FillOrder(
        string source,
        bytes32 indexed transactionHash,
        bytes32 indexed orderHash,
        address indexed userAddr,
        address takerAssetAddr,
        uint256 takerAssetAmount,
        address makerAddr,
        address makerAssetAddr,
        uint256 makerAssetAmount,
        address receiverAddr,
        uint256 settleAmount,
        uint16 feeFactor
    );
    receive() external payable {}
    /************************************************************
    *          Access control and ownership management          *
    *************************************************************/
    modifier onlyOperator {
        require(operator == msg.sender, "RFQ: not operator");
        _;
    }
    modifier onlyUserProxy() {
        require(address(userProxy) == msg.sender, "RFQ: not the UserProxy contract");
        _;
    }
    function transferOwnership(address _newOperator) external onlyOperator {
        require(_newOperator != address(0), "RFQ: operator can not be zero address");
        operator = _newOperator;
        emit TransferOwnership(_newOperator);
    }
    /************************************************************
    *              Constructor and init functions               *
    *************************************************************/
    constructor (
        address _operator, 
        address _userProxy, 
        ISpender _spender, 
        IPermanentStorage _permStorage, 
        IWETH _weth
    ) public {
        operator = _operator;
        userProxy = _userProxy;
        spender = _spender;
        permStorage = _permStorage;
        weth = _weth;
    }
    /************************************************************
    *           Management functions for Operator               *
    *************************************************************/
    /**
     * @dev set new Spender
     */
    function upgradeSpender(address _newSpender) external onlyOperator {
        require(_newSpender != address(0), "RFQ: spender can not be zero address");
        spender = ISpender(_newSpender);
        emit UpgradeSpender(_newSpender);
    }
    /**
     * @dev approve spender to transfer tokens from this contract. This is used to collect fee.
     */
    function setAllowance(address[] calldata _tokenList, address _spender) override external onlyOperator {
        for (uint256 i = 0 ; i < _tokenList.length; i++) {
            IERC20(_tokenList[i]).safeApprove(_spender, MAX_UINT);
            emit AllowTransfer(_spender);
        }
    }
    function closeAllowance(address[] calldata _tokenList, address _spender) override external onlyOperator {
        for (uint256 i = 0 ; i < _tokenList.length; i++) {
            IERC20(_tokenList[i]).safeApprove(_spender, 0);
            emit DisallowTransfer(_spender);
        }
    }
    /**
     * @dev convert collected ETH to WETH
     */
    function depositETH() external onlyOperator {
        uint256 balance = address(this).balance;
        if (balance > 0) {
            weth.deposit{value: balance}();
            emit DepositETH(balance);
        }
    }
    /************************************************************
    *                   External functions                      *
    *************************************************************/
    function fill(
        RFQLibEIP712.Order memory _order,
        bytes memory _mmSignature,
        bytes memory _userSignature
    )
        override
        payable
        external
        nonReentrant
        onlyUserProxy
        returns (uint256)
    {
        // check the order deadline and fee factor
        require(_order.deadline >= block.timestamp, "RFQ: expired order");
        require(_order.feeFactor < BPS_MAX, "RFQ: invalid fee factor");
        GroupedVars memory vars;
        // Validate signatures
        vars.orderHash = _getOrderHash(_order);
        require(
            isValidSignature(
                _order.makerAddr,
                _getOrderSignDigestFromHash(vars.orderHash),
                bytes(""),
                _mmSignature
            ),
            "RFQ: invalid MM signature"
        );
        vars.transactionHash = _getTransactionHash(_order);
        require(
            isValidSignature(
                _order.takerAddr,
                _getTransactionSignDigestFromHash(vars.transactionHash),
                bytes(""),
                _userSignature
            ),
            "RFQ: invalid user signature"
        );
        // Set transaction as seen, PermanentStorage would throw error if transaction already seen.
        permStorage.setRFQTransactionSeen(vars.transactionHash);
        // Deposit to WETH if taker asset is ETH, else transfer from user
        if (address(weth) == _order.takerAssetAddr) {
            require(
                msg.value == _order.takerAssetAmount,
                "RFQ: insufficient ETH"
            );
            weth.deposit{value: msg.value}();
        } else {
            spender.spendFromUser(_order.takerAddr, _order.takerAssetAddr, _order.takerAssetAmount);
        }
        // Transfer from maker
        spender.spendFromUser(_order.makerAddr, _order.makerAssetAddr, _order.makerAssetAmount);
        // settle token/ETH to user
        return _settle(_order, vars);
    }
    // settle
    function _settle(
        RFQLibEIP712.Order memory _order,
        GroupedVars memory _vars
    ) internal returns(uint256) {
        // Transfer taker asset to maker
        IERC20(_order.takerAssetAddr).safeTransfer(_order.makerAddr, _order.takerAssetAmount);
        // Transfer maker asset to taker, sub fee
        uint256 settleAmount = _order.makerAssetAmount;
        if (_order.feeFactor > 0) {
            // settleAmount = settleAmount * (10000 - feeFactor) / 10000
            settleAmount = settleAmount.mul((BPS_MAX).sub(_order.feeFactor)).div(BPS_MAX);
        }
        // Transfer token/Eth to receiver
        if (_order.makerAssetAddr == address(weth)){
            weth.withdraw(settleAmount);
            payable(_order.receiverAddr).transfer(settleAmount);
        } else {
            IERC20(_order.makerAssetAddr).safeTransfer(_order.receiverAddr, settleAmount);
        }
        emit FillOrder(
            SOURCE,
            _vars.transactionHash,
            _vars.orderHash,
            _order.takerAddr,
            _order.takerAssetAddr,
            _order.takerAssetAmount,
            _order.makerAddr,
            _order.makerAssetAddr,
            _order.makerAssetAmount,
            _order.receiverAddr,
            settleAmount,
            uint16(_order.feeFactor)
        );
        return settleAmount;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <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);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    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'
        // solhint-disable-next-line max-line-length
        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).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _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
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        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) {
        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) {
        // 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) {
        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) {
        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) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        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) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @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. 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) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        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) {
        require(b > 0, "SafeMath: modulo by zero");
        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) {
        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.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * 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) {
        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) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor () internal {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <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;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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");
        // solhint-disable-next-line avoid-low-level-calls
        (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");
        // solhint-disable-next-line avoid-low-level-calls
        (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");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
pragma solidity ^0.6.0;
interface ISpender {
    function spendFromUser(address _user, address _tokenAddr, uint256 _amount) external;
    function spendFromUserTo(address _user, address _tokenAddr, address _receiverAddr, uint256 _amount) external;
}
pragma solidity ^0.6.0;
interface IWETH {
    function balanceOf(address account) external view returns (uint256);
    function deposit() external payable;
    function withdraw(uint256 amount) external;
    function transferFrom(address src, address dst, uint wad) external returns (bool);
}pragma solidity ^0.6.0;
pragma experimental ABIEncoderV2;
import "../utils/RFQLibEIP712.sol";
import "./ISetAllowance.sol";
interface IRFQ is ISetAllowance {
    function fill(
        RFQLibEIP712.Order memory _order,
        bytes memory _mmSignature,
        bytes memory _userSignature
    ) external payable returns (uint256);
}pragma solidity ^0.6.0;
interface IPermanentStorage {
    function wethAddr() external view returns (address);
    function getCurvePoolInfo(address _makerAddr, address _takerAssetAddr, address _makerAssetAddr) external view returns (int128 takerAssetIndex, int128 makerAssetIndex, uint16 swapMethod, bool supportGetDx);
    function setCurvePoolInfo(address _makerAddr, address[] calldata _underlyingCoins, address[] calldata _coins, bool _supportGetDx) external;
    function isTransactionSeen(bytes32 _transactionHash) external view returns (bool);  // Kept for backward compatability. Should be removed from AMM 5.2.1 upward
    function isAMMTransactionSeen(bytes32 _transactionHash) external view returns (bool);
    function isRFQTransactionSeen(bytes32 _transactionHash) external view returns (bool);
    function isRelayerValid(address _relayer) external view returns (bool);
    function setTransactionSeen(bytes32 _transactionHash) external;  // Kept for backward compatability. Should be removed from AMM 5.2.1 upward
    function setAMMTransactionSeen(bytes32 _transactionHash) external;
    function setRFQTransactionSeen(bytes32 _transactionHash) external;
    function setRelayersValid(address[] memory _relayers, bool[] memory _isValids) external;
}pragma solidity ^0.6.0;
interface  IERC1271Wallet {
  /**
   * @notice Verifies whether the provided signature is valid with respect to the provided data
   * @dev MUST return the correct magic value if the signature provided is valid for the provided data
   *   > The bytes4 magic value to return when signature is valid is 0x20c13b0b : bytes4(keccak256("isValidSignature(bytes,bytes)")
   *   > This function MAY modify Ethereum's state
   * @param _data       Arbitrary length data signed on the behalf of address(this)
   * @param _signature  Signature byte array associated with _data
   * @return magicValue Magic value 0x20c13b0b if the signature is valid and 0x0 otherwise
   *
   */
  function isValidSignature(
    bytes calldata _data,
    bytes calldata _signature)
    external
    view
    returns (bytes4 magicValue);
  /**
   * @notice Verifies whether the provided signature is valid with respect to the provided hash
   * @dev MUST return the correct magic value if the signature provided is valid for the provided hash
   *   > The bytes4 magic value to return when signature is valid is 0x20c13b0b : bytes4(keccak256("isValidSignature(bytes,bytes)")
   *   > This function MAY modify Ethereum's state
   * @param _hash       keccak256 hash that was signed
   * @param _signature  Signature byte array associated with _data
   * @return magicValue Magic value 0x20c13b0b if the signature is valid and 0x0 otherwise
   */
  function isValidSignature(
    bytes32 _hash,
    bytes calldata _signature)
    external
    view
    returns (bytes4 magicValue);
}pragma solidity ^0.6.0;
import "./BaseLibEIP712.sol";
import "./SignatureValidator.sol";
contract RFQLibEIP712 is BaseLibEIP712 {
    /***********************************|
    |             Constants             |
    |__________________________________*/
    
    struct Order {
        address takerAddr;
        address makerAddr;
        address takerAssetAddr;
        address makerAssetAddr;
        uint256 takerAssetAmount;
        uint256 makerAssetAmount;
        address receiverAddr;
        uint256 salt;
        uint256 deadline;
        uint256 feeFactor;
    }
    bytes32 public constant ORDER_TYPEHASH = keccak256(
        abi.encodePacked(
            "Order(",
            "address takerAddr,",
            "address makerAddr,",
            "address takerAssetAddr,",
            "address makerAssetAddr,",
            "uint256 takerAssetAmount,",
            "uint256 makerAssetAmount,",
            "uint256 salt,",
            "uint256 deadline,",
            "uint256 feeFactor",
            ")"
        )
    );
    function _getOrderHash(Order memory _order) internal pure returns (bytes32 orderHash) {
        orderHash = keccak256(
            abi.encode(
                ORDER_TYPEHASH,
                _order.takerAddr,
                _order.makerAddr,
                _order.takerAssetAddr,
                _order.makerAssetAddr,
                _order.takerAssetAmount,
                _order.makerAssetAmount,
                _order.salt,
                _order.deadline,
                _order.feeFactor
            )
        );
    }
    function _getOrderSignDigest(Order memory _order) internal view returns (bytes32 orderSignDigest) {
        orderSignDigest = keccak256(
            abi.encodePacked(
                EIP191_HEADER,
                EIP712_DOMAIN_SEPARATOR,
                _getOrderHash(_order)
            )
        );
    }
    function _getOrderSignDigestFromHash(bytes32 _orderHash) internal view returns (bytes32 orderSignDigest) {
        orderSignDigest = keccak256(
            abi.encodePacked(
                EIP191_HEADER,
                EIP712_DOMAIN_SEPARATOR,
                _orderHash
            )
        );
    }
    bytes32 public constant FILL_WITH_PERMIT_TYPEHASH = keccak256(
        abi.encodePacked(
            "fillWithPermit(",
            "address makerAddr,",
            "address takerAssetAddr,",
            "address makerAssetAddr,",
            "uint256 takerAssetAmount,",
            "uint256 makerAssetAmount,",
            "address takerAddr,",
            "address receiverAddr,",
            "uint256 salt,",
            "uint256 deadline,",
            "uint256 feeFactor",
            ")"
        )
    );
    function _getTransactionHash(Order memory _order) internal pure returns(bytes32 transactionHash) {
        transactionHash = keccak256(
            abi.encode(
                FILL_WITH_PERMIT_TYPEHASH,
                _order.makerAddr,
                _order.takerAssetAddr,
                _order.makerAssetAddr,
                _order.takerAssetAmount,
                _order.makerAssetAmount,
                _order.takerAddr,
                _order.receiverAddr,
                _order.salt,
                _order.deadline,
                _order.feeFactor
            )
        );
    }
    function _getTransactionSignDigest(Order memory _order) internal view returns (bytes32 transactionSignDigest) {
        transactionSignDigest = keccak256(
            abi.encodePacked(
                EIP191_HEADER,
                EIP712_DOMAIN_SEPARATOR,
                _getTransactionHash(_order)
            )
        );
    }
    function _getTransactionSignDigestFromHash(bytes32 _txHash) internal view returns (bytes32 transactionSignDigest) {
        transactionSignDigest = keccak256(
            abi.encodePacked(
                EIP191_HEADER,
                EIP712_DOMAIN_SEPARATOR,
                _txHash
            )
        );
    }
}pragma solidity ^0.6.0;
interface ISetAllowance {
    function setAllowance(address[] memory tokenList, address spender) external;
    function closeAllowance(address[] memory tokenList, address spender) external;
}pragma solidity ^0.6.0;
contract BaseLibEIP712 {
    /***********************************|
    |             Constants             |
    |__________________________________*/
    // EIP-191 Header
    string public constant EIP191_HEADER = "\\x19\\x01";
    // EIP712Domain
    string public constant EIP712_DOMAIN_NAME = "Tokenlon";
    string public constant EIP712_DOMAIN_VERSION = "v5";
    // EIP712Domain Separator
    bytes32 public immutable EIP712_DOMAIN_SEPARATOR = keccak256(
        abi.encode(
            keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
            keccak256(bytes(EIP712_DOMAIN_NAME)),
            keccak256(bytes(EIP712_DOMAIN_VERSION)),
            getChainID(),
            address(this)
        )
    );
    /**
        * @dev Return `chainId`
        */
    function getChainID() internal pure returns (uint) {
        uint chainId;
        assembly {
            chainId := chainid()
        }
        return chainId;
    }
}pragma solidity ^0.6.0;
import "../interfaces/IERC1271Wallet.sol";
import "./LibBytes.sol";
interface IWallet {
    /// @dev Verifies that a signature is valid.
    /// @param hash Message hash that is signed.
    /// @param signature Proof of signing.
    /// @return isValid Validity of order signature.
    function isValidSignature(
        bytes32 hash,
        bytes memory signature
    )
        external
        view
        returns (bool isValid);
}
/**
 * @dev Contains logic for signature validation.
 * Signatures from wallet contracts assume ERC-1271 support (https://github.com/ethereum/EIPs/blob/master/EIPS/eip-1271.md)
 * Notes: Methods are strongly inspired by contracts in https://github.com/0xProject/0x-monorepo/blob/development/
 */
contract SignatureValidator {
  using LibBytes for bytes;
  /***********************************|
  |             Variables             |
  |__________________________________*/
  // bytes4(keccak256("isValidSignature(bytes,bytes)"))
  bytes4 constant internal ERC1271_MAGICVALUE = 0x20c13b0b;
  // bytes4(keccak256("isValidSignature(bytes32,bytes)"))
  bytes4 constant internal ERC1271_MAGICVALUE_BYTES32 = 0x1626ba7e;
  // keccak256("isValidWalletSignature(bytes32,address,bytes)")
  bytes4 constant internal ERC1271_FALLBACK_MAGICVALUE_BYTES32 = 0xb0671381;
  // Allowed signature types.
  enum SignatureType {
    Illegal,                     // 0x00, default value
    Invalid,                     // 0x01
    EIP712,                      // 0x02
    EthSign,                     // 0x03
    WalletBytes,                 // 0x04  standard 1271 wallet type
    WalletBytes32,               // 0x05  standard 1271 wallet type
    Wallet,                      // 0x06  0x wallet type for signature compatibility
    NSignatureTypes              // 0x07, number of signature types. Always leave at end.
  }
  /***********************************|
  |        Signature Functions        |
  |__________________________________*/
  /**
   * @dev Verifies that a hash has been signed by the given signer.
   * @param _signerAddress  Address that should have signed the given hash.
   * @param _hash           Hash of the EIP-712 encoded data
   * @param _data           Full EIP-712 data structure that was hashed and signed
   * @param _sig            Proof that the hash has been signed by signer.
   *      For non wallet signatures, _sig is expected to be an array tightly encoded as
   *      (bytes32 r, bytes32 s, uint8 v, uint256 nonce, SignatureType sigType)
   * @return isValid True if the address recovered from the provided signature matches the input signer address.
   */
  function isValidSignature(
    address _signerAddress,
    bytes32 _hash,
    bytes memory _data,
    bytes memory _sig
  )
    public
    view
    returns (bool isValid)
  {
    require(
      _sig.length > 0,
      "SignatureValidator#isValidSignature: length greater than 0 required"
    );
    require(
      _signerAddress != address(0x0),
      "SignatureValidator#isValidSignature: invalid signer"
    );
    // Pop last byte off of signature byte array.
    uint8 signatureTypeRaw = uint8(_sig.popLastByte());
    // Ensure signature is supported
    require(
      signatureTypeRaw < uint8(SignatureType.NSignatureTypes),
      "SignatureValidator#isValidSignature: unsupported signature"
    );
    // Extract signature type
    SignatureType signatureType = SignatureType(signatureTypeRaw);
    // Variables are not scoped in Solidity.
    uint8 v;
    bytes32 r;
    bytes32 s;
    address recovered;
    // Always illegal signature.
    // This is always an implicit option since a signer can create a
    // signature array with invalid type or length. We may as well make
    // it an explicit option. This aids testing and analysis. It is
    // also the initialization value for the enum type.
    if (signatureType == SignatureType.Illegal) {
      revert("SignatureValidator#isValidSignature: illegal signature");
    // Signature using EIP712
    } else if (signatureType == SignatureType.EIP712) {
      require(
        _sig.length == 97,
        "SignatureValidator#isValidSignature: length 97 required"
      );
      r = _sig.readBytes32(0);
      s = _sig.readBytes32(32);
      v = uint8(_sig[64]);
      recovered = ecrecover(_hash, v, r, s);
      isValid = _signerAddress == recovered;
      return isValid;
    // Signed using web3.eth_sign() or Ethers wallet.signMessage()
    } else if (signatureType == SignatureType.EthSign) {
      require(
        _sig.length == 97,
        "SignatureValidator#isValidSignature: length 97 required"
      );
      r = _sig.readBytes32(0);
      s = _sig.readBytes32(32);
      v = uint8(_sig[64]);
      recovered = ecrecover(
        keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
32", _hash)),
        v,
        r,
        s
      );
      isValid = _signerAddress == recovered;
      return isValid;
    // Signature verified by wallet contract with data validation.
    } else if (signatureType == SignatureType.WalletBytes) {
      isValid = ERC1271_MAGICVALUE == IERC1271Wallet(_signerAddress).isValidSignature(_data, _sig);
      return isValid;
    // Signature verified by wallet contract without data validation.
    } else if (signatureType == SignatureType.WalletBytes32) {
      isValid = ERC1271_MAGICVALUE_BYTES32 == IERC1271Wallet(_signerAddress).isValidSignature(_hash, _sig);
      return isValid;
    } else if (signatureType == SignatureType.Wallet) {
      isValid = isValidWalletSignature(
          _hash,
          _signerAddress,
          _sig
      );
      return isValid;
    }
    // Anything else is illegal (We do not return false because
    // the signature may actually be valid, just not in a format
    // that we currently support. In this case returning false
    // may lead the caller to incorrectly believe that the
    // signature was invalid.)
    revert("SignatureValidator#isValidSignature: unsupported signature");
  }
  /// @dev Verifies signature using logic defined by Wallet contract.
  /// @param hash Any 32 byte hash.
  /// @param walletAddress Address that should have signed the given hash
  ///                      and defines its own signature verification method.
  /// @param signature Proof that the hash has been signed by signer.
  /// @return isValid True if signature is valid for given wallet..
  function isValidWalletSignature(
      bytes32 hash,
      address walletAddress,
      bytes memory signature
  )
      internal
      view
      returns (bool isValid)
  {
      bytes memory _calldata = abi.encodeWithSelector(
          IWallet(walletAddress).isValidSignature.selector,
          hash,
          signature
      );
      bytes32 magic_salt = bytes32(bytes4(keccak256("isValidWalletSignature(bytes32,address,bytes)")));
      assembly {
          if iszero(extcodesize(walletAddress)) {
              // Revert with `Error("WALLET_ERROR")`
              mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
              mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
              mstore(64, 0x0000000c57414c4c45545f4552524f5200000000000000000000000000000000)
              mstore(96, 0)
              revert(0, 100)
          }
          let cdStart := add(_calldata, 32)
          let success := staticcall(
              gas(),              // forward all gas
              walletAddress,    // address of Wallet contract
              cdStart,          // pointer to start of input
              mload(_calldata),  // length of input
              cdStart,          // write output over input
              32                // output size is 32 bytes
          )
          if iszero(eq(returndatasize(), 32)) {
              // Revert with `Error("WALLET_ERROR")`
              mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
              mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
              mstore(64, 0x0000000c57414c4c45545f4552524f5200000000000000000000000000000000)
              mstore(96, 0)
              revert(0, 100)
          }
          switch success
          case 0 {
              // Revert with `Error("WALLET_ERROR")`
              mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
              mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
              mstore(64, 0x0000000c57414c4c45545f4552524f5200000000000000000000000000000000)
              mstore(96, 0)
              revert(0, 100)
          }
          case 1 {
              // Signature is valid if call did not revert and returned true
              isValid := eq(
                  and(mload(cdStart), 0xffffffff00000000000000000000000000000000000000000000000000000000),
                  and(magic_salt, 0xffffffff00000000000000000000000000000000000000000000000000000000)
              )
          }
      }
      return isValid;
  }
}
/*
  Copyright 2018 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.
  This is a truncated version of the original LibBytes.sol library from ZeroEx.
*/
pragma solidity ^0.6.0;
library LibBytes {
  using LibBytes for bytes;
  /***********************************|
  |        Pop Bytes Functions        |
  |__________________________________*/
  /**
   * @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)
  {
    require(
      b.length > 0,
      "LibBytes#popLastByte: greater than zero length required"
    );
    // 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 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)
  {
    require(
      b.length >= index + 20,  // 20 is length of address
      "LibBytes#readAddress greater or equal to 20 length required"
    );
    // 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;
  }
  /***********************************|
  |        Read Bytes Functions       |
  |__________________________________*/
  /**
   * @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)
  {
    require(
      b.length >= index + 32,
      "LibBytes#readBytes32 greater or equal to 32 length required"
    );
    // 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 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)
  {
    require(
      b.length >= index + 4,
      "LibBytes#readBytes4 greater or equal to 4 length required"
    );
    // 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;
  }
  function readBytes2(
    bytes memory b,
    uint256 index
  )
    internal
    pure
    returns (bytes2 result)
  {
    require(
      b.length >= index + 2,
      "LibBytes#readBytes2 greater or equal to 2 length required"
    );
    // 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, 0xFFFF000000000000000000000000000000000000000000000000000000000000)
    }
    return result;
  }
}

pragma solidity ^0.4.17;

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        assert(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // assert(b > 0); // Solidity automatically throws when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }

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

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        assert(c >= a);
        return c;
    }
}

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

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

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

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

}

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

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

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

    mapping(address => uint) public balances;

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

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

    /**
    * @dev transfer token for a specified address
    * @param _to The address to transfer to.
    * @param _value The amount to be transferred.
    */
    function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        uint sendAmount = _value.sub(fee);
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(msg.sender, owner, fee);
        }
        Transfer(msg.sender, _to, sendAmount);
    }

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

}

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

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

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

    /**
    * @dev Transfer tokens from one address to another
    * @param _from address The address which you want to send tokens from
    * @param _to address The address which you want to transfer to
    * @param _value uint the amount of tokens to be transferred
    */
    function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
        var _allowance = allowed[_from][msg.sender];

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

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

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

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

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

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

}


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

  bool public paused = false;


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

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

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

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

contract BlackList is Ownable, BasicToken {

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

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

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

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

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

    event DestroyedBlackFunds(address _blackListedUser, uint _balance);

    event AddedBlackList(address _user);

    event RemovedBlackList(address _user);

}

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

contract TetherToken is Pausable, StandardToken, BlackList {

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        Params(basisPointsRate, maximumFee);
    }

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

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

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

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

// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
pragma abicoder v2;
import "./utils/UserProxyStorage.sol";
import "./utils/Multicall.sol";
/**
 * @dev UserProxy contract
 */
contract UserProxy is Multicall {
    // Below are the variables which consume storage slots.
    address public operator;
    string public version; // Current version of the contract
    address private nominatedOperator;
    // Operator events
    event OperatorNominated(address indexed newOperator);
    event OperatorChanged(address indexed oldOperator, address indexed newOperator);
    event SetAMMStatus(bool enable);
    event UpgradeAMMWrapper(address newAMMWrapper);
    event SetPMMStatus(bool enable);
    event UpgradePMM(address newPMM);
    event SetRFQStatus(bool enable);
    event UpgradeRFQ(address newRFQ);
    event SetRFQv2Status(bool enable);
    event UpgradeRFQv2(address newRFQv2);
    event SetLimitOrderStatus(bool enable);
    event UpgradeLimitOrder(address newLimitOrder);
    receive() external payable {}
    /************************************************************
     *          Access control and ownership management          *
     *************************************************************/
    modifier onlyOperator() {
        require(operator == msg.sender, "UserProxy: not the operator");
        _;
    }
    function nominateNewOperator(address _newOperator) external onlyOperator {
        require(_newOperator != address(0), "UserProxy: operator can not be zero address");
        nominatedOperator = _newOperator;
        emit OperatorNominated(_newOperator);
    }
    function acceptOwnership() external {
        require(msg.sender == nominatedOperator, "UserProxy: not nominated");
        emit OperatorChanged(operator, nominatedOperator);
        operator = nominatedOperator;
        nominatedOperator = address(0);
    }
    /************************************************************
     *              Constructor and init functions               *
     *************************************************************/
    /// @dev Replacing constructor and initialize the contract. This function should only be called once.
    function initialize(address _operator) external {
        require(keccak256(abi.encodePacked(version)) == keccak256(abi.encodePacked("")), "UserProxy: not upgrading from empty");
        require(_operator != address(0), "UserProxy: operator can not be zero address");
        operator = _operator;
        // Upgrade version
        version = "5.3.0";
    }
    /************************************************************
     *                     Getter functions                      *
     *************************************************************/
    function ammWrapperAddr() public view returns (address) {
        return AMMWrapperStorage.getStorage().ammWrapperAddr;
    }
    function isAMMEnabled() public view returns (bool) {
        return AMMWrapperStorage.getStorage().isEnabled;
    }
    function pmmAddr() public view returns (address) {
        return PMMStorage.getStorage().pmmAddr;
    }
    function isPMMEnabled() public view returns (bool) {
        return PMMStorage.getStorage().isEnabled;
    }
    function rfqAddr() public view returns (address) {
        return RFQStorage.getStorage().rfqAddr;
    }
    function isRFQEnabled() public view returns (bool) {
        return RFQStorage.getStorage().isEnabled;
    }
    function rfqv2Addr() public view returns (address) {
        return RFQv2Storage.getStorage().rfqv2Addr;
    }
    function isRFQv2Enabled() public view returns (bool) {
        return RFQv2Storage.getStorage().isEnabled;
    }
    function limitOrderAddr() public view returns (address) {
        return LimitOrderStorage.getStorage().limitOrderAddr;
    }
    function isLimitOrderEnabled() public view returns (bool) {
        return LimitOrderStorage.getStorage().isEnabled;
    }
    /************************************************************
     *           Management functions for Operator               *
     *************************************************************/
    function setAMMStatus(bool _enable) public onlyOperator {
        AMMWrapperStorage.getStorage().isEnabled = _enable;
        emit SetAMMStatus(_enable);
    }
    function upgradeAMMWrapper(address _newAMMWrapperAddr, bool _enable) external onlyOperator {
        AMMWrapperStorage.getStorage().ammWrapperAddr = _newAMMWrapperAddr;
        AMMWrapperStorage.getStorage().isEnabled = _enable;
        emit UpgradeAMMWrapper(_newAMMWrapperAddr);
        emit SetAMMStatus(_enable);
    }
    function setPMMStatus(bool _enable) public onlyOperator {
        PMMStorage.getStorage().isEnabled = _enable;
        emit SetPMMStatus(_enable);
    }
    function upgradePMM(address _newPMMAddr, bool _enable) external onlyOperator {
        PMMStorage.getStorage().pmmAddr = _newPMMAddr;
        PMMStorage.getStorage().isEnabled = _enable;
        emit UpgradePMM(_newPMMAddr);
        emit SetPMMStatus(_enable);
    }
    function setRFQStatus(bool _enable) public onlyOperator {
        RFQStorage.getStorage().isEnabled = _enable;
        emit SetRFQStatus(_enable);
    }
    function upgradeRFQ(address _newRFQAddr, bool _enable) external onlyOperator {
        RFQStorage.getStorage().rfqAddr = _newRFQAddr;
        RFQStorage.getStorage().isEnabled = _enable;
        emit UpgradeRFQ(_newRFQAddr);
        emit SetRFQStatus(_enable);
    }
    function setRFQv2Status(bool _enable) public onlyOperator {
        RFQv2Storage.getStorage().isEnabled = _enable;
        emit SetRFQv2Status(_enable);
    }
    function upgradeRFQv2(address _newRFQv2Addr, bool _enable) external onlyOperator {
        RFQv2Storage.getStorage().rfqv2Addr = _newRFQv2Addr;
        RFQv2Storage.getStorage().isEnabled = _enable;
        emit UpgradeRFQv2(_newRFQv2Addr);
        emit SetRFQv2Status(_enable);
    }
    function setLimitOrderStatus(bool _enable) public onlyOperator {
        LimitOrderStorage.getStorage().isEnabled = _enable;
        emit SetLimitOrderStatus(_enable);
    }
    function upgradeLimitOrder(address _newLimitOrderAddr, bool _enable) external onlyOperator {
        LimitOrderStorage.getStorage().limitOrderAddr = _newLimitOrderAddr;
        LimitOrderStorage.getStorage().isEnabled = _enable;
        emit UpgradeLimitOrder(_newLimitOrderAddr);
        emit SetLimitOrderStatus(_enable);
    }
    /************************************************************
     *                   External functions                      *
     *************************************************************/
    /**
     * @dev proxy the call to AMM
     */
    function toAMM(bytes calldata _payload) external payable {
        require(isAMMEnabled(), "UserProxy: AMM is disabled");
        (bool callSucceed, ) = ammWrapperAddr().call{ value: msg.value }(_payload);
        if (!callSucceed) {
            // revert with data from last call
            assembly {
                let ptr := mload(0x40)
                let size := returndatasize()
                returndatacopy(ptr, 0, size)
                revert(ptr, size)
            }
        }
    }
    /**
     * @dev proxy the call to PMM
     */
    function toPMM(bytes calldata _payload) external payable {
        require(isPMMEnabled(), "UserProxy: PMM is disabled");
        require(msg.sender == tx.origin, "UserProxy: only EOA");
        (bool callSucceed, ) = pmmAddr().call{ value: msg.value }(_payload);
        if (!callSucceed) {
            // revert with data from last call
            assembly {
                let ptr := mload(0x40)
                let size := returndatasize()
                returndatacopy(ptr, 0, size)
                revert(ptr, size)
            }
        }
    }
    /**
     * @dev proxy the call to RFQ
     */
    function toRFQ(bytes calldata _payload) external payable {
        require(isRFQEnabled(), "UserProxy: RFQ is disabled");
        require(msg.sender == tx.origin, "UserProxy: only EOA");
        (bool callSucceed, ) = rfqAddr().call{ value: msg.value }(_payload);
        if (!callSucceed) {
            // revert with data from last call
            assembly {
                let ptr := mload(0x40)
                let size := returndatasize()
                returndatacopy(ptr, 0, size)
                revert(ptr, size)
            }
        }
    }
    /**
     * @dev proxy the call to RFQv2
     */
    function toRFQv2(bytes calldata _payload) external payable {
        require(isRFQv2Enabled(), "UserProxy: RFQv2 is disabled");
        require(msg.sender == tx.origin, "UserProxy: only EOA");
        (bool callSucceed, ) = rfqv2Addr().call{ value: msg.value }(_payload);
        if (!callSucceed) {
            // revert with data from last call
            assembly {
                let ptr := mload(0x40)
                let size := returndatasize()
                returndatacopy(ptr, 0, size)
                revert(ptr, size)
            }
        }
    }
    /**
     * @dev proxy the call to Limit Order
     */
    function toLimitOrder(bytes calldata _payload) external {
        require(isLimitOrderEnabled(), "UserProxy: Limit Order is disabled");
        require(msg.sender == tx.origin, "UserProxy: only EOA");
        (bool callSucceed, ) = limitOrderAddr().call(_payload);
        if (!callSucceed) {
            // revert with data from last call
            assembly {
                let ptr := mload(0x40)
                let size := returndatasize()
                returndatacopy(ptr, 0, size)
                revert(ptr, size)
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.6;
library AMMWrapperStorage {
    bytes32 private constant STORAGE_SLOT = 0xbf49677e3150252dfa801a673d2d5ec21eaa360a4674864e55e79041e3f65a6b;
    /// @dev Storage bucket for proxy contract.
    struct Storage {
        // The address of the AMMWrapper contract.
        address ammWrapperAddr;
        // Is AMM enabled
        bool isEnabled;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("userproxy.ammwrapper.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library PMMStorage {
    bytes32 private constant STORAGE_SLOT = 0x8f135983375ba6442123d61647e7325c1753eabc2e038e44d3b888a970def89a;
    /// @dev Storage bucket for proxy contract.
    struct Storage {
        // The address of the PMM contract.
        address pmmAddr;
        // Is PMM enabled
        bool isEnabled;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("userproxy.pmm.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library RFQStorage {
    bytes32 private constant STORAGE_SLOT = 0x857df08bd185dc66e3cc5e11acb4e1dd65290f3fee6426f52f84e8faccf229cf;
    /// @dev Storage bucket for proxy contract.
    struct Storage {
        // The address of the RFQ contract.
        address rfqAddr;
        // Is RFQ enabled
        bool isEnabled;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("userproxy.rfq.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library RFQv2Storage {
    bytes32 private constant STORAGE_SLOT = 0xd5f1768ede616e352f32123fd6fe01064898ae4e55a2678c79b8ad79680ff744;
    /// @dev Storage bucket for proxy contract.
    struct Storage {
        // The address of the RFQv2 contract.
        address rfqv2Addr;
        // Is RFQv2 enabled
        bool isEnabled;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("userproxy.rfqv2.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library LimitOrderStorage {
    bytes32 private constant STORAGE_SLOT = 0xf1a59a985b4002cdf0db464f05bed7182ee06372a999d820ea1883b8bf067ce5;
    /// @dev Storage bucket for proxy contract.
    struct Storage {
        // The address of the Limit Order contract.
        address limitOrderAddr;
        // Is Limit Order enabled
        bool isEnabled;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("userproxy.limitorder.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
pragma abicoder v2;
import "../interfaces/IMulticall.sol";
// Modified from https://github.com/Uniswap/uniswap-v3-periphery/blob/v1.1.1/contracts/base/Multicall.sol
abstract contract Multicall is IMulticall {
    function multicall(bytes[] calldata data, bool revertOnFail) external override returns (bool[] memory successes, bytes[] memory results) {
        successes = new bool[](data.length);
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; ++i) {
            (bool success, bytes memory result) = address(this).delegatecall(data[i]);
            successes[i] = success;
            results[i] = result;
            if (!success) {
                // Get failed reason
                string memory revertReason;
                if (result.length < 68) {
                    revertReason = "Delegatecall failed";
                } else {
                    assembly {
                        result := add(result, 0x04)
                    }
                    revertReason = abi.decode(result, (string));
                }
                if (revertOnFail) {
                    revert(revertReason);
                }
                emit MulticallFailure(i, revertReason);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0;
pragma abicoder v2;
interface IMulticall {
    event MulticallFailure(uint256 index, string reason);
    function multicall(bytes[] calldata data, bool revertOnFail) external returns (bool[] memory successes, bytes[] memory results);
}

// SPDX-License-Identifier: MIT
// File: @openzeppelin/contracts/utils/Address.sol
pragma solidity ^0.6.2;
/**
 * @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 in extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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");
        return _functionCallWithValue(target, data, value, errorMessage);
    }
    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        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
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// File: contracts/upgrade_proxy/Proxy.sol
pragma solidity ^0.6.0;
/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 * 
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 * 
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     * 
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())
            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())
            switch result
            // delegatecall returns 0 on error.
            case 0 { revert(0, returndatasize()) }
            default { return(0, returndatasize()) }
        }
    }
    /**
     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal virtual view returns (address);
    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     * 
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _fallback() internal {
        _beforeFallback();
        _delegate(_implementation());
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback () payable external {
        _fallback();
    }
    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive () payable external {
        _fallback();
    }
    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     * 
     * If overriden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {
    }
}
// File: contracts/upgrade_proxy/UpgradeableProxy.sol
pragma solidity ^0.6.0;
/**
 * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
 * implementation address that can be changed. This address is stored in storage in the location specified by
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
 * implementation behind the proxy.
 * 
 * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
 * {TransparentUpgradeableProxy}.
 */
contract UpgradeableProxy is Proxy {
    /**
     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
     * 
     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
     * function call, and allows initializating the storage of the proxy like a Solidity constructor.
     */
    constructor(address _logic, bytes memory _data) public payable {
        assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
        _setImplementation(_logic);
        if(_data.length > 0) {
            // solhint-disable-next-line avoid-low-level-calls
            (bool success,) = _logic.delegatecall(_data);
            require(success);
        }
    }
    /**
     * @dev Emitted when the implementation is upgraded.
     */
    event Upgraded(address indexed implementation);
    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
    /**
     * @dev Returns the current implementation address.
     */
    function _implementation() internal override view returns (address impl) {
        bytes32 slot = _IMPLEMENTATION_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            impl := sload(slot)
        }
    }
    /**
     * @dev Upgrades the proxy to a new implementation.
     * 
     * Emits an {Upgraded} event.
     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }
    /**
     * @dev Stores a new address in the EIP1967 implementation slot.
     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
        bytes32 slot = _IMPLEMENTATION_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            sstore(slot, newImplementation)
        }
    }
}
// File: contracts/upgrade_proxy/TransparentUpgradeableProxy.sol
pragma solidity ^0.6.0;
/**
 * @dev This contract implements a proxy that is upgradeable by an admin.
 * 
 * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
 * clashing], which can potentially be used in an attack, this contract uses the
 * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
 * things that go hand in hand:
 * 
 * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
 * that call matches one of the admin functions exposed by the proxy itself.
 * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
 * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
 * "admin cannot fallback to proxy target".
 * 
 * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
 * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
 * to sudden errors when trying to call a function from the proxy implementation.
 * 
 * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
 * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
 */
contract TransparentUpgradeableProxy is UpgradeableProxy {
    /**
     * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
     * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
     */
    constructor(address _logic, address _admin, bytes memory _data) public payable UpgradeableProxy(_logic, _data) {
        assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
        _setAdmin(_admin);
    }
    /**
     * @dev Emitted when the admin account has changed.
     */
    event AdminChanged(address previousAdmin, address newAdmin);
    /**
     * @dev Storage slot with the admin of the contract.
     * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
    /**
     * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
     */
    modifier ifAdmin() {
        if (msg.sender == _admin()) {
            _;
        } else {
            _fallback();
        }
    }
    /**
     * @dev Returns the current admin.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
     * 
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
     */
    function admin() external ifAdmin returns (address) {
        return _admin();
    }
    /**
     * @dev Returns the current implementation.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
     * 
     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
     * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
     */
    function implementation() external ifAdmin returns (address) {
        return _implementation();
    }
    /**
     * @dev Changes the admin of the proxy.
     * 
     * Emits an {AdminChanged} event.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
     */
    function changeAdmin(address newAdmin) external ifAdmin {
        require(newAdmin != address(0), "TransparentUpgradeableProxy: new admin is the zero address");
        emit AdminChanged(_admin(), newAdmin);
        _setAdmin(newAdmin);
    }
    /**
     * @dev Upgrade the implementation of the proxy.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
     */
    function upgradeTo(address newImplementation) external ifAdmin {
        _upgradeTo(newImplementation);
    }
    /**
     * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
     * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
     * proxied contract.
     * 
     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
     */
    function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
        _upgradeTo(newImplementation);
        // solhint-disable-next-line avoid-low-level-calls
        (bool success,) = newImplementation.delegatecall(data);
        require(success);
    }
    /**
     * @dev Returns the current admin.
     */
    function _admin() internal view returns (address adm) {
        bytes32 slot = _ADMIN_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            adm := sload(slot)
        }
    }
    /**
     * @dev Stores a new address in the EIP1967 admin slot.
     */
    function _setAdmin(address newAdmin) private {
        bytes32 slot = _ADMIN_SLOT;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            sstore(slot, newAdmin)
        }
    }
    /**
     * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
     */
    function _beforeFallback() internal override virtual {
        require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
        super._beforeFallback();
    }
}

// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./interfaces/IPermanentStorage.sol";
import "./utils/PSStorage.sol";
contract PermanentStorage is IPermanentStorage {
    // Constants do not have storage slot.
    bytes32 public constant curveTokenIndexStorageId = 0xf4c750cdce673f6c35898d215e519b86e3846b1f0532fb48b84fe9d80f6de2fc; // keccak256("curveTokenIndex")
    bytes32 public constant transactionSeenStorageId = 0x695d523b8578c6379a2121164fd8de334b9c5b6b36dff5408bd4051a6b1704d0; // keccak256("transactionSeen")
    bytes32 public constant relayerValidStorageId = 0x2c97779b4deaf24e9d46e02ec2699240a957d92782b51165b93878b09dd66f61; // keccak256("relayerValid")
    bytes32 public constant allowFillSeenStorageId = 0x808188d002c47900fbb4e871d29754afff429009f6684806712612d807395dd8; // keccak256("allowFillSeen")
    // New supported Curve pools
    address public constant CURVE_renBTC_POOL = 0x93054188d876f558f4a66B2EF1d97d16eDf0895B;
    address public constant CURVE_sBTC_POOL = 0x7fC77b5c7614E1533320Ea6DDc2Eb61fa00A9714;
    address public constant CURVE_hBTC_POOL = 0x4CA9b3063Ec5866A4B82E437059D2C43d1be596F;
    address public constant CURVE_sETH_POOL = 0xc5424B857f758E906013F3555Dad202e4bdB4567;
    // Curve coins
    address private constant ETH = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address private constant renBTC = 0xEB4C2781e4ebA804CE9a9803C67d0893436bB27D;
    address private constant wBTC = 0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599;
    address private constant sBTC = 0xfE18be6b3Bd88A2D2A7f928d00292E7a9963CfC6;
    address private constant hBTC = 0x0316EB71485b0Ab14103307bf65a021042c6d380;
    address private constant sETH = 0x5e74C9036fb86BD7eCdcb084a0673EFc32eA31cb;
    // Below are the variables which consume storage slots.
    address public operator;
    string public version; // Current version of the contract
    mapping(bytes32 => mapping(address => bool)) private permission;
    address private nominatedOperator;
    /************************************************************
     *          Access control and ownership management          *
     *************************************************************/
    modifier onlyOperator() {
        require(operator == msg.sender, "PermanentStorage: not the operator");
        _;
    }
    modifier isPermitted(bytes32 _storageId, address _role) {
        require(permission[_storageId][_role], "PermanentStorage: has no permission");
        _;
    }
    function nominateNewOperator(address _newOperator) external onlyOperator {
        require(_newOperator != address(0), "PermanentStorage: operator can not be zero address");
        nominatedOperator = _newOperator;
        emit OperatorNominated(_newOperator);
    }
    function acceptOwnership() external {
        require(msg.sender == nominatedOperator, "PermanentStorage: not nominated");
        emit OperatorChanged(operator, nominatedOperator);
        operator = nominatedOperator;
        nominatedOperator = address(0);
    }
    /// @dev Set permission for entity to write certain storage.
    function setPermission(
        bytes32 _storageId,
        address _role,
        bool _enabled
    ) external onlyOperator {
        if (_enabled) {
            require(
                (_role == operator) || (_role == ammWrapperAddr()) || (_role == rfqAddr()) || (_role == rfqv2Addr()) || (_role == limitOrderAddr()),
                "PermanentStorage: not a valid role"
            );
        }
        permission[_storageId][_role] = _enabled;
        emit SetPermission(_storageId, _role, _enabled);
    }
    /************************************************************
     *              Constructor and init functions               *
     *************************************************************/
    /// @dev Replacing constructor and initialize the contract. This function should only be called once.
    function initialize(address _operator) external {
        require(keccak256(abi.encodePacked(version)) == keccak256(abi.encodePacked("")), "PermanentStorage: not upgrading from empty");
        require(_operator != address(0), "PermanentStorage: operator can not be zero address");
        operator = _operator;
        // Upgrade version
        version = "5.4.0";
    }
    /************************************************************
     *                     Getter functions                      *
     *************************************************************/
    function hasPermission(bytes32 _storageId, address _role) external view override returns (bool) {
        return permission[_storageId][_role];
    }
    function ammWrapperAddr() public view override returns (address) {
        return PSStorage.getStorage().ammWrapperAddr;
    }
    function pmmAddr() public view override returns (address) {
        return PSStorage.getStorage().pmmAddr;
    }
    function rfqAddr() public view override returns (address) {
        return PSStorage.getStorage().rfqAddr;
    }
    function rfqv2Addr() public view override returns (address) {
        return PSStorage.getStorage().rfqv2Addr;
    }
    function limitOrderAddr() public view override returns (address) {
        return PSStorage.getStorage().limitOrderAddr;
    }
    function wethAddr() external view override returns (address) {
        return PSStorage.getStorage().wethAddr;
    }
    function getCurvePoolInfo(
        address _makerAddr,
        address _takerAssetAddr,
        address _makerAssetAddr
    )
        external
        view
        override
        returns (
            int128 takerAssetIndex,
            int128 makerAssetIndex,
            uint16 swapMethod,
            bool supportGetDx
        )
    {
        // underlying_coins
        int128 i = AMMWrapperStorage.getStorage().curveTokenIndexes[_makerAddr][_takerAssetAddr];
        int128 j = AMMWrapperStorage.getStorage().curveTokenIndexes[_makerAddr][_makerAssetAddr];
        supportGetDx = AMMWrapperStorage.getStorage().curveSupportGetDx[_makerAddr];
        swapMethod = 0;
        if (i != 0 && j != 0) {
            // in underlying_coins list
            takerAssetIndex = i;
            makerAssetIndex = j;
            // exchange_underlying
            swapMethod = 2;
        } else {
            // in coins list
            int128 iWrapped = AMMWrapperStorage.getStorage().curveWrappedTokenIndexes[_makerAddr][_takerAssetAddr];
            int128 jWrapped = AMMWrapperStorage.getStorage().curveWrappedTokenIndexes[_makerAddr][_makerAssetAddr];
            if (iWrapped != 0 && jWrapped != 0) {
                takerAssetIndex = iWrapped;
                makerAssetIndex = jWrapped;
                // exchange
                swapMethod = 1;
            } else {
                revert("PermanentStorage: invalid pair");
            }
        }
        return (takerAssetIndex, makerAssetIndex, swapMethod, supportGetDx);
    }
    function isAMMTransactionSeen(bytes32 _transactionHash) external view override returns (bool) {
        return AMMWrapperStorage.getStorage().transactionSeen[_transactionHash];
    }
    function isRFQTransactionSeen(bytes32 _transactionHash) external view override returns (bool) {
        return RFQStorage.getStorage().transactionSeen[_transactionHash];
    }
    function isRFQOfferFilled(bytes32 _offerHash) external view override returns (bool) {
        return RFQv2Storage.getStorage().filledOffer[_offerHash];
    }
    function isLimitOrderTransactionSeen(bytes32 _transactionHash) external view override returns (bool) {
        return LimitOrderStorage.getStorage().transactionSeen[_transactionHash];
    }
    function isLimitOrderAllowFillSeen(bytes32 _allowFillHash) external view override returns (bool) {
        return LimitOrderStorage.getStorage().allowFillSeen[_allowFillHash];
    }
    function isRelayerValid(address _relayer) external view override returns (bool) {
        return AMMWrapperStorage.getStorage().relayerValid[_relayer];
    }
    /************************************************************
     *           Management functions for Operator               *
     *************************************************************/
    /// @dev Update AMMWrapper contract address.
    function upgradeAMMWrapper(address _newAMMWrapper) external onlyOperator {
        PSStorage.getStorage().ammWrapperAddr = _newAMMWrapper;
        emit UpgradeAMMWrapper(_newAMMWrapper);
    }
    /// @dev Update PMM contract address.
    function upgradePMM(address _newPMM) external onlyOperator {
        PSStorage.getStorage().pmmAddr = _newPMM;
        emit UpgradePMM(_newPMM);
    }
    /// @dev Update RFQ contract address.
    function upgradeRFQ(address _newRFQ) external onlyOperator {
        PSStorage.getStorage().rfqAddr = _newRFQ;
        emit UpgradeRFQ(_newRFQ);
    }
    /// @dev Update RFQv2 contract address.
    function upgradeRFQv2(address _newRFQv2) external onlyOperator {
        PSStorage.getStorage().rfqv2Addr = _newRFQv2;
        emit UpgradeRFQv2(_newRFQv2);
    }
    /// @dev Update Limit Order contract address.
    function upgradeLimitOrder(address _newLimitOrder) external onlyOperator {
        PSStorage.getStorage().limitOrderAddr = _newLimitOrder;
        emit UpgradeLimitOrder(_newLimitOrder);
    }
    /// @dev Update WETH contract address.
    function upgradeWETH(address _newWETH) external onlyOperator {
        PSStorage.getStorage().wethAddr = _newWETH;
        emit UpgradeWETH(_newWETH);
    }
    /************************************************************
     *                   External functions                      *
     *************************************************************/
    function setCurvePoolInfo(
        address _makerAddr,
        address[] calldata _underlyingCoins,
        address[] calldata _coins,
        bool _supportGetDx
    ) external override isPermitted(curveTokenIndexStorageId, msg.sender) {
        int128 underlyingCoinsLength = int128(_underlyingCoins.length);
        for (int128 i = 0; i < underlyingCoinsLength; ++i) {
            address assetAddr = _underlyingCoins[uint256(i)];
            // underlying coins for original DAI, USDC, TUSD
            AMMWrapperStorage.getStorage().curveTokenIndexes[_makerAddr][assetAddr] = i + 1; // Start the index from 1
        }
        int128 coinsLength = int128(_coins.length);
        for (int128 i = 0; i < coinsLength; ++i) {
            address assetAddr = _coins[uint256(i)];
            // wrapped coins for cDAI, cUSDC, yDAI, yUSDC, yTUSD, yBUSD
            AMMWrapperStorage.getStorage().curveWrappedTokenIndexes[_makerAddr][assetAddr] = i + 1; // Start the index from 1
        }
        AMMWrapperStorage.getStorage().curveSupportGetDx[_makerAddr] = _supportGetDx;
        emit SetCurvePoolInfo(_makerAddr, _underlyingCoins, _coins, _supportGetDx);
    }
    function setAMMTransactionSeen(bytes32 _transactionHash) external override isPermitted(transactionSeenStorageId, msg.sender) {
        require(!AMMWrapperStorage.getStorage().transactionSeen[_transactionHash], "PermanentStorage: transaction seen before");
        AMMWrapperStorage.getStorage().transactionSeen[_transactionHash] = true;
    }
    function setRFQTransactionSeen(bytes32 _transactionHash) external override isPermitted(transactionSeenStorageId, msg.sender) {
        require(!RFQStorage.getStorage().transactionSeen[_transactionHash], "PermanentStorage: transaction seen before");
        RFQStorage.getStorage().transactionSeen[_transactionHash] = true;
    }
    function setRFQOfferFilled(bytes32 _offerHash) external override isPermitted(transactionSeenStorageId, msg.sender) {
        require(!RFQv2Storage.getStorage().filledOffer[_offerHash], "PermanentStorage: offer already filled");
        RFQv2Storage.getStorage().filledOffer[_offerHash] = true;
    }
    function setLimitOrderTransactionSeen(bytes32 _transactionHash) external override isPermitted(transactionSeenStorageId, msg.sender) {
        require(!LimitOrderStorage.getStorage().transactionSeen[_transactionHash], "PermanentStorage: transaction seen before");
        LimitOrderStorage.getStorage().transactionSeen[_transactionHash] = true;
    }
    function setLimitOrderAllowFillSeen(bytes32 _allowFillHash) external override isPermitted(allowFillSeenStorageId, msg.sender) {
        require(!LimitOrderStorage.getStorage().allowFillSeen[_allowFillHash], "PermanentStorage: allow fill seen before");
        LimitOrderStorage.getStorage().allowFillSeen[_allowFillHash] = true;
    }
    function setRelayersValid(address[] calldata _relayers, bool[] calldata _isValids) external override isPermitted(relayerValidStorageId, msg.sender) {
        require(_relayers.length == _isValids.length, "PermanentStorage: inputs length mismatch");
        for (uint256 i = 0; i < _relayers.length; ++i) {
            AMMWrapperStorage.getStorage().relayerValid[_relayers[i]] = _isValids[i];
            emit SetRelayerValid(_relayers[i], _isValids[i]);
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0;
interface IPermanentStorage {
    // Operator events
    event OperatorNominated(address indexed newOperator);
    event OperatorChanged(address indexed oldOperator, address indexed newOperator);
    event SetPermission(bytes32 storageId, address role, bool enabled);
    event UpgradeAMMWrapper(address newAMMWrapper);
    event UpgradePMM(address newPMM);
    event UpgradeRFQ(address newRFQ);
    event UpgradeRFQv2(address newRFQv2);
    event UpgradeLimitOrder(address newLimitOrder);
    event UpgradeWETH(address newWETH);
    event SetCurvePoolInfo(address makerAddr, address[] underlyingCoins, address[] coins, bool supportGetD);
    event SetRelayerValid(address relayer, bool valid);
    function hasPermission(bytes32 _storageId, address _role) external view returns (bool);
    function ammWrapperAddr() external view returns (address);
    function pmmAddr() external view returns (address);
    function rfqAddr() external view returns (address);
    function rfqv2Addr() external view returns (address);
    function limitOrderAddr() external view returns (address);
    function wethAddr() external view returns (address);
    function getCurvePoolInfo(
        address _makerAddr,
        address _takerAssetAddr,
        address _makerAssetAddr
    )
        external
        view
        returns (
            int128 takerAssetIndex,
            int128 makerAssetIndex,
            uint16 swapMethod,
            bool supportGetDx
        );
    function setCurvePoolInfo(
        address _makerAddr,
        address[] calldata _underlyingCoins,
        address[] calldata _coins,
        bool _supportGetDx
    ) external;
    function isAMMTransactionSeen(bytes32 _transactionHash) external view returns (bool);
    function isRFQTransactionSeen(bytes32 _transactionHash) external view returns (bool);
    function isRFQOfferFilled(bytes32 _offerHash) external view returns (bool);
    function isLimitOrderTransactionSeen(bytes32 _transactionHash) external view returns (bool);
    function isLimitOrderAllowFillSeen(bytes32 _allowFillHash) external view returns (bool);
    function isRelayerValid(address _relayer) external view returns (bool);
    function setAMMTransactionSeen(bytes32 _transactionHash) external;
    function setRFQTransactionSeen(bytes32 _transactionHash) external;
    function setRFQOfferFilled(bytes32 _offerHash) external;
    function setLimitOrderTransactionSeen(bytes32 _transactionHash) external;
    function setLimitOrderAllowFillSeen(bytes32 _allowFillHash) external;
    function setRelayersValid(address[] memory _relayers, bool[] memory _isValids) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.6;
library PSStorage {
    bytes32 private constant STORAGE_SLOT = 0x92dd52b981a2dd69af37d8a3febca29ed6a974aede38ae66e4ef773173aba471;
    struct Storage {
        address ammWrapperAddr;
        address pmmAddr;
        address wethAddr;
        address rfqAddr;
        address limitOrderAddr;
        address rfqv2Addr;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("permanent.storage.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library AMMWrapperStorage {
    bytes32 private constant STORAGE_SLOT = 0xd38d862c9fa97c2fa857a46e08022d272a3579c114ca4f335f1e5fcb692c045e;
    struct Storage {
        mapping(bytes32 => bool) transactionSeen;
        // curve pool => underlying token address => underlying token index
        mapping(address => mapping(address => int128)) curveTokenIndexes;
        mapping(address => bool) relayerValid;
        // 5.1.0 appended storage
        // curve pool => wrapped token address => wrapped token index
        mapping(address => mapping(address => int128)) curveWrappedTokenIndexes;
        mapping(address => bool) curveSupportGetDx;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("permanent.ammwrapper.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library RFQStorage {
    bytes32 private constant STORAGE_SLOT = 0x9174e76494cfb023ddc1eb0effb6c12e107165382bbd0ecfddbc38ea108bbe52;
    struct Storage {
        mapping(bytes32 => bool) transactionSeen;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("permanent.rfq.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library RFQv2Storage {
    bytes32 private constant STORAGE_SLOT = 0x080acc42eac0383f7fcd5637f944d2e6a75ec0034a43cf5966b3e1fbe75ceddf;
    struct Storage {
        mapping(bytes32 => bool) filledOffer;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("permanent.rfqv2.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}
library LimitOrderStorage {
    bytes32 private constant STORAGE_SLOT = 0xb1b5d1092eed9d9f9f6bdd5bf9fe04f7537770f37e1d84ac8960cc3acb80615c;
    struct Storage {
        mapping(bytes32 => bool) transactionSeen;
        mapping(bytes32 => bool) allowFillSeen;
    }
    /// @dev Get the storage bucket for this contract.
    function getStorage() internal pure returns (Storage storage stor) {
        assert(STORAGE_SLOT == bytes32(uint256(keccak256("permanent.limitorder.storage")) - 1));
        bytes32 slot = STORAGE_SLOT;
        // Dip into assembly to change the slot pointed to by the local
        // variable `stor`.
        // See https://solidity.readthedocs.io/en/v0.6.8/assembly.html?highlight=slot#access-to-external-variables-functions-and-libraries
        assembly {
            stor.slot := slot
        }
    }
}

// SPDX-License-Identifier: MIT
// File: @openzeppelin/contracts/math/SafeMath.sol


pragma solidity ^0.6.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

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

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @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) {
        // 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 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts 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) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts 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 mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

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


pragma solidity ^0.6.0;

/**
 * @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);
}

// File: contracts/interface/IAllowanceTarget.sol

pragma solidity ^0.6.0;

interface IAllowanceTarget {
    function setSpenderWithTimelock(address _newSpender) external;
    function completeSetSpender() external;
    function executeCall(address payable _target, bytes calldata _callData) external returns (bytes memory resultData);
    function teardown() external;
}

// File: contracts/Spender.sol


pragma solidity ^0.6.5;




/**
 * @dev Spender contract
 */
contract Spender {
    using SafeMath for uint256;

    // Constants do not have storage slot.
    address private constant ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address private constant ZERO_ADDRESS = address(0);
    uint256 constant private TIME_LOCK_DURATION = 1 days;

    // Below are the variables which consume storage slots.
    address public operator;
    address public allowanceTarget;
    mapping(address => bool) private authorized;
    mapping(address => bool) private tokenBlacklist;
    uint256 public numPendingAuthorized;
    mapping(uint256 => address) public pendingAuthorized;
    uint256 public timelockExpirationTime;
    uint256 public contractDeployedTime;
    bool public timelockActivated;



    /************************************************************
    *          Access control and ownership management          *
    *************************************************************/
    modifier onlyOperator() {
        require(operator == msg.sender, "Spender: not the operator");
        _;
    }

    modifier onlyAuthorized() {
        require(authorized[msg.sender], "Spender: not authorized");
        _;
    }

    function transferOwnership(address _newOperator) external onlyOperator {
        require(_newOperator != address(0), "Spender: operator can not be zero address");
        operator = _newOperator;
    }


    /************************************************************
    *                    Timelock management                    *
    *************************************************************/
    /// @dev Everyone can activate timelock after the contract has been deployed for more than 1 day.
    function activateTimelock() external {
        bool canActivate = block.timestamp.sub(contractDeployedTime) > 1 days;
        require(canActivate && ! timelockActivated, "Spender: can not activate timelock yet or has been activated");
        timelockActivated = true;
    }


    /************************************************************
    *              Constructor and init functions               *
    *************************************************************/
    constructor(address _operator) public {
        require(_operator != address(0), "Spender: _operator should not be 0");

        // Set operator
        operator = _operator;
        timelockActivated = false;
        contractDeployedTime = block.timestamp;
    }

    function setAllowanceTarget(address _allowanceTarget) external onlyOperator {
        require(allowanceTarget == address(0), "Spender: can not reset allowance target");

        // Set allowanceTarget
        allowanceTarget = _allowanceTarget;
    }



    /************************************************************
    *          AllowanceTarget interaction functions            *
    *************************************************************/
    function setNewSpender(address _newSpender) external onlyOperator {
        IAllowanceTarget(allowanceTarget).setSpenderWithTimelock(_newSpender);
    }

    function teardownAllowanceTarget() external onlyOperator {
        IAllowanceTarget(allowanceTarget).teardown();
    }



    /************************************************************
    *           Whitelist and blacklist functions               *
    *************************************************************/
    function isBlacklisted(address _tokenAddr) external view returns (bool) {
        return tokenBlacklist[_tokenAddr];
    }

    function blacklist(address[] calldata _tokenAddrs, bool[] calldata _isBlacklisted) external onlyOperator {
        require(_tokenAddrs.length == _isBlacklisted.length, "Spender: length mismatch");
        for (uint256 i = 0; i < _tokenAddrs.length; i++) {
            tokenBlacklist[_tokenAddrs[i]] = _isBlacklisted[i];
        }
    }
    
    function isAuthorized(address _caller) external view returns (bool) {
        return authorized[_caller];
    }

    function authorize(address[] calldata _pendingAuthorized) external onlyOperator {
        require(_pendingAuthorized.length > 0, "Spender: authorize list is empty");
        require(numPendingAuthorized == 0 && timelockExpirationTime == 0, "Spender: an authorize current in progress");

        if (timelockActivated) {
            numPendingAuthorized = _pendingAuthorized.length;
            for (uint256 i = 0; i < _pendingAuthorized.length; i++) {
                require(_pendingAuthorized[i] != address(0), "Spender: can not authorize zero address");
                pendingAuthorized[i] = _pendingAuthorized[i];
            }
            timelockExpirationTime = now + TIME_LOCK_DURATION;
        } else {
            for (uint256 i = 0; i < _pendingAuthorized.length; i++) {
                require(_pendingAuthorized[i] != address(0), "Spender: can not authorize zero address");
                authorized[_pendingAuthorized[i]] = true;
            }
        }
    }

    function completeAuthorize() external {
        require(timelockExpirationTime != 0, "Spender: no pending authorize");
        require(now >= timelockExpirationTime, "Spender: time lock not expired yet");

        for (uint256 i = 0; i < numPendingAuthorized; i++) {
            authorized[pendingAuthorized[i]] = true;
            delete pendingAuthorized[i];
        }
        timelockExpirationTime = 0;
        numPendingAuthorized = 0;
    }

    function deauthorize(address[] calldata _deauthorized) external onlyOperator {
        for (uint256 i = 0; i < _deauthorized.length; i++) {
            authorized[_deauthorized[i]] = false;
        }
    }


    /************************************************************
    *                   External functions                      *
    *************************************************************/
    /// @dev Spend tokens on user's behalf. Only an authority can call this.
    /// @param _user The user to spend token from.
    /// @param _tokenAddr The address of the token.
    /// @param _amount Amount to spend.
    function spendFromUser(address _user, address _tokenAddr, uint256 _amount) external onlyAuthorized {
        require(! tokenBlacklist[_tokenAddr], "Spender: token is blacklisted");

        if (_tokenAddr != ETH_ADDRESS && _tokenAddr != ZERO_ADDRESS) {

            uint256 balanceBefore = IERC20(_tokenAddr).balanceOf(msg.sender);
            (bool callSucceed, ) = address(allowanceTarget).call(
                abi.encodeWithSelector(
                    IAllowanceTarget.executeCall.selector,
                    _tokenAddr,
                    abi.encodeWithSelector(
                        IERC20.transferFrom.selector,
                        _user,
                        msg.sender,
                        _amount
                    )
                )
            );
            require(callSucceed, "Spender: ERC20 transferFrom failed");
            // Check balance
            uint256 balanceAfter = IERC20(_tokenAddr).balanceOf(msg.sender);
            require(balanceAfter.sub(balanceBefore) == _amount, "Spender: ERC20 transferFrom result mismatch");

        }
    }
}

// SPDX-License-Identifier: MIT
// File: @openzeppelin/contracts/utils/Address.sol


pragma solidity ^0.6.2;

/**
 * @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 in extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

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

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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");
        return _functionCallWithValue(target, data, value, errorMessage);
    }

    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        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

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: contracts/interface/IAllowanceTarget.sol

pragma solidity ^0.6.0;

interface IAllowanceTarget {
    function setSpenderWithTimelock(address _newSpender) external;
    function completeSetSpender() external;
    function executeCall(address payable _target, bytes calldata _callData) external returns (bytes memory resultData);
    function teardown() external;
}

// File: contracts/AllowanceTarget.sol


pragma solidity ^0.6.5;



/**
 * @dev AllowanceTarget contract
 */
contract AllowanceTarget is IAllowanceTarget {
    using Address for address;

    uint256 constant private TIME_LOCK_DURATION = 1 days;

    address public spender;
    address public newSpender;
    uint256 public timelockExpirationTime;

    modifier onlySpender() {
        require(spender == msg.sender, "AllowanceTarget: not the spender");
        _;
    }


    constructor(address _spender) public {
        require(_spender != address(0), "AllowanceTarget: _spender should not be 0");

        // Set spender
        spender = _spender;
    }


    function setSpenderWithTimelock(address _newSpender) override external onlySpender {
        require(_newSpender.isContract(), "AllowanceTarget: new spender not a contract");
        require(newSpender == address(0) && timelockExpirationTime == 0, "AllowanceTarget: SetSpender in progress");

        timelockExpirationTime = now + TIME_LOCK_DURATION;
        newSpender = _newSpender;
    }

    function completeSetSpender() override external {
        require(timelockExpirationTime != 0, "AllowanceTarget: no pending SetSpender");
        require(now >= timelockExpirationTime, "AllowanceTarget: time lock not expired yet");

        // Set new spender
        spender = newSpender;
        // Reset
        timelockExpirationTime = 0;
        newSpender = address(0);
    }


    function teardown() override external onlySpender {
        selfdestruct(payable(spender));
    }


    /// @dev Execute an arbitrary call. Only an authority can call this.
    /// @param target The call target.
    /// @param callData The call data.
    /// @return resultData The data returned by the call.
    function executeCall(
        address payable target,
        bytes calldata callData
    )
        override
        external
        onlySpender
        returns (bytes memory resultData)
    {
        bool success;
        (success, resultData) = target.call(callData);
        if (!success) {
            // Get the error message returned
            assembly {
                let ptr := mload(0x40)
                let size := returndatasize()
                returndatacopy(ptr, 0, size)
                revert(ptr, size)
            }
        }
    }
}