ETH Price: $2,259.16 (-7.62%)

Transaction Decoder

Block:
16837815 at Mar-16-2023 03:42:47 AM +UTC
Transaction Fee:
0.004599926505053778 ETH $10.39
Gas Used:
261,957 Gas / 17.559853354 Gwei

Emitted Events:

131 UUPSProxy.0x40218dc7047d6a284746d042d62140b3629db83daefcd944659e90b4c74b7eb0( 0x40218dc7047d6a284746d042d62140b3629db83daefcd944659e90b4c74b7eb0, 0x0000000000000000000000000000000000000000000000000000000000000000, 0x000000000000000000000000eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee, 0x000000000000000000000000995d77ee73135fd2a8eaaca8e84be45389c2f51e, 0000000000000000000000000000000000000000000000000000000000000b52, 0000000000000000000000000000000000000000000000000000000000000038, 000000000000000000000000e9e7cea3dedca5984780bafc599bd69add087d56, 0000000000000000000000000000000000000000000000476b111aaa389b5882, 0000000000000000000000000000000000000000000000000000000000000190, 000000000000000000000000eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee, 0000000000000000000000000000000000000000000000000b1a2bc2ec500000, 000000000000000000000000236694d65052eef5d7fea101a392ad9245f3bc00, 00000000000000000000000000000000000000000000000000017dfcdece4000, 000000000000000000000000000000000000000000000000000110d9316ec000 )

Account State Difference:

  Address   Before After State Difference Code
0x236694D6...245F3BC00
0.879259806053577793 Eth
Nonce: 2
0.074659879548524015 Eth
Nonce: 3
0.804599926505053778
0x4315f344...1fcA37D57
(XY Finance : YBridge)
3.734488715464283718 Eth4.534488715464283718 Eth0.8
(beaverbuild)
31.746067649922823808 Eth31.746333155274727115 Eth0.000265505351903307

Execution Trace

ETH 0.8 UUPSProxy.2aac3cac( )
  • ETH 0.8 XSwapper.swapWithReferrer( aggregatorAdaptor=0x0000000000000000000000000000000000000000, swapDesc=[{name:fromToken, type:address, order:1, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:toToken, type:address, order:2, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:receiver, type:address, order:3, indexed:false, value:0x236694D65052Eef5d7fEA101a392aD9245F3BC00, valueString:0x236694D65052Eef5d7fEA101a392aD9245F3BC00}, {name:amount, type:uint256, order:4, indexed:false, value:800000000000000000, valueString:800000000000000000}, {name:minReturnAmount, type:uint256, order:5, indexed:false, value:800000000000000000, valueString:800000000000000000}], aggregatorData=0x00, toChainDesc=[{name:toChainId, type:uint32, order:1, indexed:false, value:56, valueString:56}, {name:toChainToken, type:address, order:2, indexed:false, value:0xe9e7CEA3DedcA5984780Bafc599bD69ADd087D56, valueString:0xe9e7CEA3DedcA5984780Bafc599bD69ADd087D56}, {name:expectedToChainTokenAmount, type:uint256, order:3, indexed:false, value:1317433806188437002370, valueString:1317433806188437002370}, {name:slippage, type:uint32, order:4, indexed:false, value:400, valueString:400}], referrer=0x995d77eE73135FD2a8EaAcA8e84Be45389C2f51E )
    File 1 of 2: UUPSProxy
    // SPDX-License-Identifier: BUSL-1.1
    pragma solidity 0.8.2;
    import "ERC1967Proxy.sol";
    contract UUPSProxy is ERC1967Proxy {
        constructor(address _logic, bytes memory _data) ERC1967Proxy(_logic, _data) payable {}
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "Proxy.sol";
    import "ERC1967Upgrade.sol";
    /**
     * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
     * implementation address that can be changed. This address is stored in storage in the location specified by
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
     * implementation behind the proxy.
     */
    contract ERC1967Proxy is Proxy, ERC1967Upgrade {
        /**
         * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
         *
         * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
         * function call, and allows initializating the storage of the proxy like a Solidity constructor.
         */
        constructor(address _logic, bytes memory _data) payable {
            assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
            _upgradeToAndCall(_logic, _data, false);
        }
        /**
         * @dev Returns the current implementation address.
         */
        function _implementation() internal view virtual override returns (address impl) {
            return ERC1967Upgrade._getImplementation();
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
     * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
     * be specified by overriding the virtual {_implementation} function.
     *
     * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
     * different contract through the {_delegate} function.
     *
     * The success and return data of the delegated call will be returned back to the caller of the proxy.
     */
    abstract contract Proxy {
        /**
         * @dev Delegates the current call to `implementation`.
         *
         * This function does not return to its internall call site, it will return directly to the external caller.
         */
        function _delegate(address implementation) internal virtual {
            assembly {
                // Copy msg.data. We take full control of memory in this inline assembly
                // block because it will not return to Solidity code. We overwrite the
                // Solidity scratch pad at memory position 0.
                calldatacopy(0, 0, calldatasize())
                // Call the implementation.
                // out and outsize are 0 because we don't know the size yet.
                let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                // Copy the returned data.
                returndatacopy(0, 0, returndatasize())
                switch result
                // delegatecall returns 0 on error.
                case 0 {
                    revert(0, returndatasize())
                }
                default {
                    return(0, returndatasize())
                }
            }
        }
        /**
         * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
         * and {_fallback} should delegate.
         */
        function _implementation() internal view virtual returns (address);
        /**
         * @dev Delegates the current call to the address returned by `_implementation()`.
         *
         * This function does not return to its internall call site, it will return directly to the external caller.
         */
        function _fallback() internal virtual {
            _beforeFallback();
            _delegate(_implementation());
        }
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
         * function in the contract matches the call data.
         */
        fallback() external payable virtual {
            _fallback();
        }
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
         * is empty.
         */
        receive() external payable virtual {
            _fallback();
        }
        /**
         * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
         * call, or as part of the Solidity `fallback` or `receive` functions.
         *
         * If overriden should call `super._beforeFallback()`.
         */
        function _beforeFallback() internal virtual {}
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.2;
    import "IBeacon.sol";
    import "Address.sol";
    import "StorageSlot.sol";
    /**
     * @dev This abstract contract provides getters and event emitting update functions for
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
     *
     * _Available since v4.1._
     *
     * @custom:oz-upgrades-unsafe-allow delegatecall
     */
    abstract contract ERC1967Upgrade {
        // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
        bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
        /**
         * @dev Storage slot with the address of the current implementation.
         * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
        /**
         * @dev Emitted when the implementation is upgraded.
         */
        event Upgraded(address indexed implementation);
        /**
         * @dev Returns the current implementation address.
         */
        function _getImplementation() internal view returns (address) {
            return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 implementation slot.
         */
        function _setImplementation(address newImplementation) private {
            require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
            StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
        }
        /**
         * @dev Perform implementation upgrade
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeTo(address newImplementation) internal {
            _setImplementation(newImplementation);
            emit Upgraded(newImplementation);
        }
        /**
         * @dev Perform implementation upgrade with additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCall(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            _upgradeTo(newImplementation);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(newImplementation, data);
            }
        }
        /**
         * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCallSecure(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            address oldImplementation = _getImplementation();
            // Initial upgrade and setup call
            _setImplementation(newImplementation);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(newImplementation, data);
            }
            // Perform rollback test if not already in progress
            StorageSlot.BooleanSlot storage rollbackTesting = StorageSlot.getBooleanSlot(_ROLLBACK_SLOT);
            if (!rollbackTesting.value) {
                // Trigger rollback using upgradeTo from the new implementation
                rollbackTesting.value = true;
                Address.functionDelegateCall(
                    newImplementation,
                    abi.encodeWithSignature("upgradeTo(address)", oldImplementation)
                );
                rollbackTesting.value = false;
                // Check rollback was effective
                require(oldImplementation == _getImplementation(), "ERC1967Upgrade: upgrade breaks further upgrades");
                // Finally reset to the new implementation and log the upgrade
                _upgradeTo(newImplementation);
            }
        }
        /**
         * @dev Storage slot with the admin of the contract.
         * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
        /**
         * @dev Emitted when the admin account has changed.
         */
        event AdminChanged(address previousAdmin, address newAdmin);
        /**
         * @dev Returns the current admin.
         */
        function _getAdmin() internal view returns (address) {
            return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 admin slot.
         */
        function _setAdmin(address newAdmin) private {
            require(newAdmin != address(0), "ERC1967: new admin is the zero address");
            StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
        }
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _changeAdmin(address newAdmin) internal {
            emit AdminChanged(_getAdmin(), newAdmin);
            _setAdmin(newAdmin);
        }
        /**
         * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
         * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
         */
        bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
        /**
         * @dev Emitted when the beacon is upgraded.
         */
        event BeaconUpgraded(address indexed beacon);
        /**
         * @dev Returns the current beacon.
         */
        function _getBeacon() internal view returns (address) {
            return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
        }
        /**
         * @dev Stores a new beacon in the EIP1967 beacon slot.
         */
        function _setBeacon(address newBeacon) private {
            require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
            require(
                Address.isContract(IBeacon(newBeacon).implementation()),
                "ERC1967: beacon implementation is not a contract"
            );
            StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
        }
        /**
         * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
         * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
         *
         * Emits a {BeaconUpgraded} event.
         */
        function _upgradeBeaconToAndCall(
            address newBeacon,
            bytes memory data,
            bool forceCall
        ) internal {
            _setBeacon(newBeacon);
            emit BeaconUpgraded(newBeacon);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev This is the interface that {BeaconProxy} expects of its beacon.
     */
    interface IBeacon {
        /**
         * @dev Must return an address that can be used as a delegate call target.
         *
         * {BeaconProxy} will check that this address is a contract.
         */
        function implementation() external view returns (address);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            assembly {
                size := extcodesize(account)
            }
            return size > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Library for reading and writing primitive types to specific storage slots.
     *
     * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
     * This library helps with reading and writing to such slots without the need for inline assembly.
     *
     * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
     *
     * Example usage to set ERC1967 implementation slot:
     * ```
     * contract ERC1967 {
     *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
     *
     *     function _getImplementation() internal view returns (address) {
     *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
     *     }
     *
     *     function _setImplementation(address newImplementation) internal {
     *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
     *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
     *     }
     * }
     * ```
     *
     * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
     */
    library StorageSlot {
        struct AddressSlot {
            address value;
        }
        struct BooleanSlot {
            bool value;
        }
        struct Bytes32Slot {
            bytes32 value;
        }
        struct Uint256Slot {
            uint256 value;
        }
        /**
         * @dev Returns an `AddressSlot` with member `value` located at `slot`.
         */
        function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
         */
        function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
         */
        function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
         */
        function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
            assembly {
                r.slot := slot
            }
        }
    }
    

    File 2 of 2: XSwapper
    // SPDX-License-Identifier: BUSL-1.1
    pragma solidity 0.8.2;
    import { Address } from "Address.sol";
    import "AccessControlUpgradeable.sol";
    import "UUPSUpgradeable.sol";
    import "PausableUpgradeable.sol";
    import "ERC20.sol";
    import "ECDSA.sol";
    import "SafeERC20.sol";
    import "ReentrancyGuard.sol";
    import "Supervisor.sol";
    import "IDexAggregatorAdaptor.sol";
    import "IYPoolVault.sol";
    /// @title XSwapper contract
    /// @notice Users call `swap` to swap asset to specified bridgeable asset and then initiate a cross-chain swap request.
    /// YPool workers call `closeSwap` to complete a cross-chain swap, `claim` & `batchClaim` to claim the credit back.
    /// YPool validators call `lockCloseSwap` & `refund` to lock the swap and refund asset back to user if no applicable
    /// liquidity or a YPool worker sent an invalidated closeSwap tx.
    /// - "User" and "Account" refer to the same thing
    /// - "fromChain" and "source chain" refer to the same thing
    /// - "toChain" and "target chain" refer to the same thing
    /// - "XYChain" and "Settlement chain" refer to the same thing
    contract XSwapper is AccessControlUpgradeable, UUPSUpgradeable, PausableUpgradeable, ReentrancyGuard {
        using SafeERC20 for IERC20;
        using ECDSA for bytes32;
        /* ========== STRUCTURE ========== */
        // Status of a swap request (on source chain)
        enum RequestStatus { Open, Closed }
        // Result of a swap when it's closed (on target chain)
        enum CloseSwapResult { NonSwapped, Success, Failed, Locked }
        // Type of how the asset is transferred when the swap is completed
        enum CompleteSwapType { Claimed, FreeClaimed, Refunded }
        // Fees settings on each chain
        // Fee is calculated as `inputAmount * FeeStructure.rate / (10 ** FeeStructure.decimals)`
        struct FeeStructure {
            bool isSet;
            uint256 gas;
            uint256 min;
            uint256 max;
            uint256 rate;
            uint256 decimals;
        }
        // Info of a swap request
        struct SwapRequest {
            uint32 toChainId;
            uint256 swapId;
            address receiver;
            address sender;
            uint256 YPoolTokenAmount;
            uint256 xyFee;
            uint256 gasFee;
            IERC20 YPoolToken;
            RequestStatus status;
        }
        // Info of an expecting swap on target chain of a swap request
        struct ToChainDescription {
            uint32 toChainId;
            IERC20 toChainToken;
            uint256 expectedToChainTokenAmount;
            uint32 slippage;
        }
        /* ========== STATE VARIABLES ========== */
        // Roles
        bytes32 public constant ROLE_OWNER = keccak256("ROLE_OWNER");
        bytes32 public constant ROLE_MANAGER = keccak256("ROLE_MANAGER");
        bytes32 public constant ROLE_STAFF = keccak256("ROLE_STAFF");
        bytes32 public constant ROLE_YPOOL_WORKER = keccak256("ROLE_YPOOL_WORKER");
        // Mapping of YPool token to its max amount in a single swap
        mapping (address => uint256) public maxYPoolTokenSwapAmount;
        // A contract that supervises each refund and claim by providing signatures
        Supervisor public supervisor;
        // A referenced address of native currency
        address public constant ETHER_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
        // Id of the current chain
        uint32 public chainId;
        // Next available id of a swap request
        // Note: the value is monotonically increasing as there MUST NOT exist swap requests with same Id
        // Note: swapId must be set to start accepting swap requests.
        uint256 public swapId;
        // The starting swap Id of the XSwapper
        // Note: It is immutable after setting startSwapId
        uint256 public startSwapId;
        // Note: swapIdIsSet should only be set to True and freeze once in function `setStartSwapId`
        bool public swapIdIsSet;
        // Accept swap requests or not
        bool public acceptSwapRequest;
        // Identifier address for those interacting with XSwapper without help of APIs
        // Note: This address will not receive any token as profit for being a default referrer
        address public constant DEGEN_USER_IDENTIFIER = 0xFD19727868A8197F42e7a52d024374598F62953B;
        // Close status of each swap
        mapping (bytes32 => bool) everClosed;
        // Supported YPool tokens
        mapping (address => bool) public YPoolSupportedToken;
        // YPoolVault of a YPoolSupportedToken
        mapping (address => address) public YPoolVaults;
        // Whitelist of AggregatorAdaptors
        mapping (address => bool) public isWhitelistedAggregatorAdaptor;
        // SwapValidator contract on XYChain that validates a `closeSwap` transaction
        // Note: this contract does not exist on periphery chains so its address is used only for signature verification purpose in `claim` and `batchClaim`
        address public swapValidatorXYChain;
        // Fees setting of a supported token on each chain
        mapping (bytes32 => FeeStructure) public feeStructures;
        // All swap requests initiated by users
        mapping (uint256 => SwapRequest) public swapRequests;
        // 2022-09-28 Upgrade: Support single chain swap
        // Whitelist of Aggregators
        mapping (address => bool) public isWhitelistedAggregator;
        receive() external payable {}
        function _authorizeUpgrade(address) internal override onlyRole(ROLE_OWNER) {}
        /// @notice Initialize XSwapper
        /// @param owner The owner address
        /// @param manager The manager address
        /// @param staff The staff address
        /// @param worker The swap worker address
        /// @param _supervisor The supervisor contract address
        /// @param _chainId The chain ID
        function initialize(address owner, address manager, address staff, address worker, address _supervisor, uint32 _chainId) initializer public {
            require(Address.isContract(_supervisor), "ERR_SUPERVISOR_NOT_CONTRACT");
            supervisor = Supervisor(_supervisor);
            chainId = _chainId;
            acceptSwapRequest = false;
            // Validate chainId
            uint256 _realChainId;
            assembly {
                _realChainId := chainid()
            }
            require(_chainId == _realChainId, "ERR_WRONG_CHAIN_ID");
            _setRoleAdmin(ROLE_OWNER, ROLE_OWNER);
            _setRoleAdmin(ROLE_MANAGER, ROLE_OWNER);
            _setRoleAdmin(ROLE_STAFF, ROLE_OWNER);
            _setRoleAdmin(ROLE_YPOOL_WORKER, ROLE_OWNER);
            _setupRole(ROLE_OWNER, owner);
            _setupRole(ROLE_MANAGER, manager);
            _setupRole(ROLE_STAFF, staff);
            _setupRole(ROLE_YPOOL_WORKER, worker);
        }
        /* ========== MODIFIERS ========== */
        modifier acceptSwap() {
            require(acceptSwapRequest, "ERR_NOT_ACCEPTING_SWAP_REQUESTS");
            _;
        }
        /* ========== PRIVATE FUNCTIONS ========== */
        function max(uint256 a, uint256 b) private pure returns (uint256) {
            return a >= b ? a : b;
        }
        function min(uint256 a, uint256 b) private pure returns (uint256) {
            return a < b ? a : b;
        }
        /// @notice Get the XY protocol fee setting of `_token` on chain `_toChainId`
        /// @param _toChainId Chain Id of the periphery chain
        /// @param _token YPool token
        function _getFeeStructure(uint32 _toChainId, address _token) private view returns (FeeStructure memory) {
            bytes32 universalTokenId = keccak256(abi.encodePacked(_toChainId, _token));
            return feeStructures[universalTokenId];
        }
        function _safeTransferAsset(address receiver, IERC20 token, uint256 amount) private {
            if (address(token) == ETHER_ADDRESS) {
                payable(receiver).transfer(amount);
            } else {
                token.safeTransfer(receiver, amount);
            }
        }
        function _safeTransferFromAsset(IERC20 fromToken, address from, uint256 amount) private {
            if (address(fromToken) == ETHER_ADDRESS)
                require(msg.value == amount, "ERR_INVALID_AMOUNT");
            else {
                uint256 _fromTokenBalance = getTokenBalance(fromToken, address(this));
                fromToken.safeTransferFrom(from, address(this), amount);
                require(getTokenBalance(fromToken, address(this)) - _fromTokenBalance == amount, "ERR_INVALID_AMOUNT");
            }
        }
        /// @notice Check whether the swap amount reaches the threshold or not
        /// @param _toChainId Chain Id of the target chain
        /// @param token YPool token
        /// @param amount Swap amount
        /// @dev A swap could be closed by YPool worker on target chain or get refunded on source chain, i.e., this chain,
        /// therefore, we require the `amount` not only be GTE the fee on target chain but also on source chain
        function _checkMinimumSwapAmount(uint32 _toChainId, IERC20 token, uint256 amount) private view returns (bool) {
            FeeStructure memory feeStructure = _getFeeStructure(_toChainId, address(token));
            require(feeStructure.isSet, "ERR_FEE_NOT_SET");
            uint256 minToChainFee = feeStructure.min;  // closeSwap
            feeStructure = _getFeeStructure(chainId, address(token));
            require(feeStructure.isSet, "ERR_FEE_NOT_SET");
            uint256 minFromChainFee = feeStructure.min;  // refund
            return amount >= max(minToChainFee, minFromChainFee);
        }
        /// @notice Calculate the XY protocol fee and gas fee
        /// @param _chainId Chain Id of the periphery chain
        /// @param token YPool token
        /// @param amount YPool token amount
        function _calculateFee(uint32 _chainId, IERC20 token, uint256 amount) private view returns (uint256 xyFee, uint256 gasFee) {
            FeeStructure memory feeStructure = _getFeeStructure(_chainId, address(token));
            require(feeStructure.isSet, "ERR_FEE_NOT_SET");
            xyFee = amount * feeStructure.rate / (10 ** feeStructure.decimals);
            xyFee = min(max(xyFee, feeStructure.min), feeStructure.max);
            gasFee = feeStructure.gas;
        }
        /// @notice This functions is called invoked by `swap` or `swapWithReferrer`. Either way performs the swap requested and emit an event with referrer address.
        /// @dev swapDesc is the swap info for swapping on DEX on this chain, not the swap request
        /// @param aggregatorAdaptor The address of the adaptor of the specific dex aggregator
        /// @param swapDesc Description of the swap on DEX, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for YPool token
        /// @param toChainDesc Description of the swap on target chain, see ToChainDescription
        /// @param referrer Referrer of the swap
        function _swap(
            address aggregatorAdaptor,
            IDexAggregatorAdaptor.SwapDescription memory swapDesc,
            bytes memory aggregatorData,
            ToChainDescription calldata toChainDesc,
            address referrer
        ) private {
            require(swapIdIsSet, "ERR_SWAP_ID_NOT_SET");
            address receiver = swapDesc.receiver;
            IERC20 fromToken = swapDesc.fromToken;
            IERC20 YPoolToken = swapDesc.toToken;
            require(YPoolSupportedToken[address(YPoolToken)], "ERR_INVALID_YPOOL_TOKEN");
            uint256 fromTokenAmount = swapDesc.amount;
            uint256 yBalance;
            _safeTransferFromAsset(fromToken, msg.sender, fromTokenAmount);
            if (fromToken == YPoolToken) {
                yBalance = fromTokenAmount;
            } else {
                require(isWhitelistedAggregatorAdaptor[aggregatorAdaptor], "ERR_INVALID_AGGREGATOR_ADAPTOR");
                yBalance = getTokenBalance(YPoolToken, address(this));
                swapDesc.receiver = address(this);
                if (address(fromToken) != ETHER_ADDRESS) fromToken.safeApprove(aggregatorAdaptor, fromTokenAmount);
                IDexAggregatorAdaptor(aggregatorAdaptor).swap{value: msg.value}(swapDesc, aggregatorData);
                if (address(fromToken) != ETHER_ADDRESS) fromToken.safeApprove(aggregatorAdaptor, 0);
                yBalance = getTokenBalance(YPoolToken, address(this)) - yBalance;
            }
            require(_checkMinimumSwapAmount(toChainDesc.toChainId, YPoolToken, yBalance), "ERR_NOT_ENOUGH_SWAP_AMOUNT");
            require(yBalance <= maxYPoolTokenSwapAmount[address(YPoolToken)], "ERR_EXCEED_MAX_SWAP_AMOUNT");
            // Calculate XY fee and gas fee for closeSwap on toChain
            // NOTE: XY fee already includes gas fee and gas fee is computed here only for bookkeeping purpose
            (uint256 xyFee, uint256 closeSwapGasFee) = _calculateFee(toChainDesc.toChainId, YPoolToken, yBalance);
            SwapRequest memory request = SwapRequest(toChainDesc.toChainId, swapId, receiver, msg.sender, yBalance, xyFee, closeSwapGasFee, YPoolToken, RequestStatus.Open);
            swapRequests[swapId] = request;
            emit SwapRequested(swapId++, aggregatorAdaptor, toChainDesc, fromToken, YPoolToken, yBalance, receiver, xyFee, closeSwapGasFee, referrer);
        }
        /// @notice This functions performs a single chain swap.
        /// @param aggregator The address of the dex aggregator
        /// @param swapDesc Description of the swap on dex aggregator, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for desired token
        /// @param referrer Referrer of the swap
        function _singleChainSwap(
            address aggregator,
            IDexAggregatorAdaptor.SwapDescription memory swapDesc,
            bytes memory aggregatorData,
            address referrer
        ) private {
            require(isWhitelistedAggregator[aggregator], "ERR_INVALID_AGGREGATOR");
            require(swapDesc.receiver != address(0), "ERR_INVALID_RECEIVER");
            address receiver = swapDesc.receiver;
            IERC20 fromToken = swapDesc.fromToken;
            IERC20 toToken = swapDesc.toToken;
            require(toToken != fromToken, "ERR_TO_TOKEN");
            uint256 fromTokenAmount = swapDesc.amount;
            uint256 toTokenBalance = getTokenBalance(toToken, receiver);
            if (address(fromToken) != ETHER_ADDRESS) {
                fromToken.safeTransferFrom(msg.sender, address(this), fromTokenAmount);
                fromToken.safeApprove(aggregator, fromTokenAmount);
            } else {
                require(msg.value == fromTokenAmount, "ERR_INVALID_VALUE");
            }
            Address.functionCallWithValue(aggregator, aggregatorData, msg.value, "call to Aggregator failed");
            if (address(fromToken) != ETHER_ADDRESS) fromToken.safeApprove(aggregator, 0);
            uint256 toTokenAmountOut = getTokenBalance(toToken, receiver) - toTokenBalance;
            require(toTokenAmountOut >= swapDesc.minReturnAmount, "ERR_RETURN_AMOUNT_NOT_ENOUGH");
            emit AggregatorSwapped(aggregator, msg.sender, fromToken, toToken, receiver, fromTokenAmount, toTokenAmountOut, referrer);
        }
        /* ========== VIEW FUNCTIONS ========== */
        /// @notice Get a certain swap request
        /// @dev TODO: Though swapRequests is a public mapping, here we keep getSwapRequest for those applications that need this interface. Should be removed since next upgrade.
        /// @param _swapId Swap Id of a swap request
        function getSwapRequest(uint256 _swapId) external view returns (SwapRequest memory) {
            return swapRequests[_swapId];
        }
        /// @notice Get the XY protocol fee setting of `_token` on chain `_toChainId`
        /// @param _chainId Chain Id of the periphery chain
        /// @param _token YPool token
        function getFeeStructure(uint32 _chainId, address _token) external view returns (FeeStructure memory) {
            FeeStructure memory feeStructure = _getFeeStructure(_chainId, _token);
            require(feeStructure.isSet, "ERR_FEE_NOT_SET");
            return feeStructure;
        }
        /// @notice Check whether a swap is closed or not on this chain, assuming this chain is the target chain
        /// @param _chainId Chain Id of the source chain
        /// @param _swapId Swap Id of a swap request
        function getEverClosed(uint32 _chainId, uint256 _swapId) external view returns (bool) {
            bytes32 universalSwapId = keccak256(abi.encodePacked(_chainId, _swapId));
            return everClosed[universalSwapId];
        }
        /// @notice Get the token or native token balance of given account
        /// @param _token ERC20 token address or ETHER_ADDRESS which stands for native token
        /// @param _account YPool token
        function getTokenBalance(IERC20 _token, address _account) public view returns (uint256 balance) {
            balance = address(_token) == ETHER_ADDRESS ? _account.balance : _token.balanceOf(_account);
        }
        /* ========== RESTRICTED FUNCTIONS (OWNER) ========== */
        /// @notice Set start swapId
        /// @dev swapId can only be set once and before any swap request comes in
        /// @param _swapId Swap Id of a swap request
        function setStartSwapId(uint256 _swapId) external onlyRole(ROLE_OWNER) {
            require(!swapIdIsSet, "ERR_SWAP_ID_ALREADY_SET");
            swapIdIsSet = true;
            startSwapId = _swapId;
            swapId = _swapId;
            emit StartSwapIdSet(_swapId);
        }
        /// @notice Set YPoolVault and its token
        /// @param _supportedToken YPool token
        /// @param _vault Address of the YPoolVault
        /// @param _isSet To Add or to remove
        function setYPoolVault(address _supportedToken, address _vault, bool _isSet) external onlyRole(ROLE_OWNER) {
            if (_supportedToken != ETHER_ADDRESS) {
                require(Address.isContract(_supportedToken), "ERR_YPOOL_TOKEN_NOT_CONTRACT");
            }
            require(Address.isContract(_vault), "ERR_YPOOL_VAULT_NOT_CONTRACT");
            YPoolSupportedToken[_supportedToken] = _isSet;
            YPoolVaults[_supportedToken] = _vault;
            emit YPoolVaultSet(_supportedToken, _vault, _isSet);
        }
        /// @notice Rescue fund accidentally sent to this contract. Can not rescue YPool token
        /// @param tokens List of token address to rescue
        function rescue(IERC20[] memory tokens) external onlyRole(ROLE_OWNER) {
            for (uint256 i; i < tokens.length; i++) {
                IERC20 token = tokens[i];
                require(!YPoolSupportedToken[address(token)], "ERR_CAN_NOT_RESCUE_YPOOL_TOKEN");
                uint256 _tokenBalance = token.balanceOf(address(this));
                token.safeTransfer(msg.sender, _tokenBalance);
            }
        }
        /* ========== RESTRICTED FUNCTIONS (MANAGER) ========== */
        /// @notice Set the maximum swap amount of a YPool token
        /// @param _supportedToken YPool token
        /// @param amount Maximum swap amount
        function setMaxYPoolTokenSwapAmount(address _supportedToken, uint256 amount) external onlyRole(ROLE_MANAGER) {
            require(YPoolSupportedToken[_supportedToken], "ERR_INVALID_YPOOL_TOKEN");
            maxYPoolTokenSwapAmount[_supportedToken] = amount;
        }
        /// @notice Set the dex aggregator adaptor
        /// @param _aggregatorAdaptor Address of the adaptor of the aggregator
        function setAggregatorAdaptor(address _aggregatorAdaptor, bool _isSet) external onlyRole(ROLE_MANAGER) {
            require(Address.isContract(_aggregatorAdaptor), "ERR_AGGREGATOR_ADAPTOR_NOT_CONTRACT");
            require(isWhitelistedAggregatorAdaptor[_aggregatorAdaptor] != _isSet, "ERR_ALREADY_SET");
            isWhitelistedAggregatorAdaptor[_aggregatorAdaptor] = _isSet;
            emit AggregatorAdaptorSet(_aggregatorAdaptor, _isSet);
        }
        /// @notice Set the dex aggregator
        /// @param _aggregator Address of the aggregator
        function setAggregator(address _aggregator, bool _isSet) external onlyRole(ROLE_MANAGER) {
            require(Address.isContract(_aggregator), "ERR_AGGREGATOR_ADAPTOR_NOT_CONTRACT");
            require(isWhitelistedAggregator[_aggregator] != _isSet, "ERR_ALREADY_SET");
            isWhitelistedAggregator[_aggregator] = _isSet;
            emit AggregatorSet(_aggregator, _isSet);
        }
        /// @notice Pause the major functions
        function pause() external onlyRole(ROLE_MANAGER) {
            _pause();
        }
        /// @notice Unpause the major functions
        function unpause() external onlyRole(ROLE_MANAGER) {
            _unpause();
        }
        /// @notice Set to accept swap request or not
        function setAcceptSwapRequest(bool _isSet) external onlyRole(ROLE_MANAGER) {
            require(acceptSwapRequest != _isSet, "ERR_ALREADY_SET");
            acceptSwapRequest = _isSet;
            emit AcceptSwapRequestSet(_isSet);
        }
        /* ========== RESTRICTED FUNCTIONS (STAFF) ========== */
        /// @notice Set the XY protocol fee setting of `_token` on chain `_toChainId`
        /// @param _toChainId Chain Id of the periphery chain
        /// @param _supportedToken YPool token
        /// @param _gas Estimated gas fee of closeSwap/refund in form of YPool Token
        /// @param _min Minimum amount of the XY protocol fee of `_supportedToken`
        /// @param _max Maximum amount of the XY protocol fee of `_supportedToken`
        /// @param rate Fee rate of the XY protocol fee of `_supportedToken`
        /// @param decimals Decimals of `_rate`
        function setFeeStructure(uint32 _toChainId, address _supportedToken, uint256 _gas, uint256 _min, uint256 _max, uint256 rate, uint256 decimals) external onlyRole(ROLE_STAFF) {
            if (_supportedToken != ETHER_ADDRESS) {
                require(Address.isContract(_supportedToken), "ERR_YPOOL_TOKEN_NOT_CONTRACT");
            }
            require(_max > _min, "ERR_INVALID_MAX_MIN");
            require(_min >= _gas, "ERR_INVALID_MIN_GAS");
            bytes32 universalTokenId = keccak256(abi.encodePacked(_toChainId, _supportedToken));
            FeeStructure memory feeStructure = FeeStructure(true, _gas, _min, _max, rate, decimals);
            feeStructures[universalTokenId] = feeStructure;
            emit FeeStructureSet(_toChainId, _supportedToken, _gas, _min, _max, rate, decimals);
        }
        /// @notice Set the SwapValidator
        /// @param _swapValidatorXYChain Address of the SwapValidator on XY chain
        function setSwapValidatorXYChain(address _swapValidatorXYChain) external onlyRole(ROLE_STAFF) {
            swapValidatorXYChain = _swapValidatorXYChain;
            emit SwapValidatorXYChainSet(_swapValidatorXYChain);
        }
        /* ========== RESTRICTED FUNCTIONS (YPOOL_WORKER) ========== */
        /// @notice Fulfill a swap request for a user by YPool worker
        /// Closing a swap MUST be performed on target chain and only by YPool worker
        /// @dev swapDesc is the swap info for swapping on DEX on target chain, not the info of the swap request user initiated on source chain
        /// @param aggregatorAdaptor The address of the adaptor of the specific dex aggregator
        /// @param swapDesc Description of the swap on DEX, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for YPool token
        /// @param fromChainId Source chain id of the swap request
        /// @param fromSwapId Swap id of the swap request
        function closeSwap(
            address aggregatorAdaptor,
            IDexAggregatorAdaptor.SwapDescription calldata swapDesc,
            bytes memory aggregatorData,
            uint32 fromChainId,
            uint256 fromSwapId
        ) external payable whenNotPaused nonReentrant onlyRole(ROLE_YPOOL_WORKER) {
            require(YPoolSupportedToken[address(swapDesc.fromToken)], "ERR_INVALID_YPOOL_TOKEN");
            {
                bytes32 universalSwapId = keccak256(abi.encodePacked(fromChainId, fromSwapId));
                require(!everClosed[universalSwapId], "ERR_ALREADY_CLOSED");
                everClosed[universalSwapId] = true;
            }
            require(swapDesc.amount <= maxYPoolTokenSwapAmount[address(swapDesc.fromToken)], "ERR_EXCEED_MAX_SWAP_AMOUNT");
            IYPoolVault(YPoolVaults[address(swapDesc.fromToken)]).transferToSwapper(swapDesc.fromToken, swapDesc.amount);
            uint256 toTokenAmountOut;
            CloseSwapResult swapResult;
            if (swapDesc.toToken == swapDesc.fromToken) {
                toTokenAmountOut = swapDesc.amount;
                swapResult = CloseSwapResult.NonSwapped;
            } else {
                require(isWhitelistedAggregatorAdaptor[aggregatorAdaptor], "ERR_INVALID_AGGREGATOR_ADAPTOR");
                uint256 value = (address(swapDesc.fromToken) == ETHER_ADDRESS) ? swapDesc.amount : 0;
                // If the swapDesc.toToken doest not consist of balanceOf, considered as swap failed
                try this.getTokenBalance(swapDesc.toToken, swapDesc.receiver) returns (uint256 balance) {
                    toTokenAmountOut = balance;
                    if (address(swapDesc.fromToken) != ETHER_ADDRESS) swapDesc.fromToken.safeApprove(aggregatorAdaptor, swapDesc.amount);
                    try IDexAggregatorAdaptor(aggregatorAdaptor).swap{value: value}(swapDesc, aggregatorData) {
                        toTokenAmountOut = getTokenBalance(swapDesc.toToken, swapDesc.receiver) - toTokenAmountOut;
                        swapResult = CloseSwapResult.Success;
                    } catch {
                        swapResult = CloseSwapResult.Failed;
                    }
                    if (address(swapDesc.fromToken) != ETHER_ADDRESS) swapDesc.fromToken.safeApprove(aggregatorAdaptor, 0);
                } catch {
                    swapResult = CloseSwapResult.Failed;
                }
            }
            if (swapResult != CloseSwapResult.Success) {
                _safeTransferAsset(swapDesc.receiver, swapDesc.fromToken, swapDesc.amount);
            }
            emit CloseSwapCompleted(swapResult, fromChainId, fromSwapId);
            emit SwappedForUser(aggregatorAdaptor, swapDesc.fromToken, swapDesc.amount, swapDesc.toToken, toTokenAmountOut, swapDesc.receiver);
        }
        /* ========== RESTRICTED FUNCTIONS (SIGNATURE REQUIRED) ========== */
        /// @notice Claim the asset of a swap request on source chain after YPool worker `closeSwap` on target chain, by providing signatures of validators
        /// Claiming MUST be performed on source chain
        /// @dev Signatures from validators are first sent to SwapValidator contract on Settlement chain to validate a swap request. Then the signatures can be reused here to approve the claim
        /// @param _swapId Swap id of the swap request
        /// @param signatures Signatures of validators
        function claim(uint256 _swapId, bytes[] memory signatures) external whenNotPaused {
            require(startSwapId <= _swapId && _swapId < swapId, "ERR_INVALID_SWAPID");
            require(swapRequests[_swapId].status != RequestStatus.Closed, "ERR_ALREADY_CLOSED");
            swapRequests[_swapId].status = RequestStatus.Closed;
            bytes32 sigId = keccak256(abi.encodePacked(supervisor.VALIDATE_SWAP_IDENTIFIER(), address(this), address(swapValidatorXYChain), chainId, _swapId));
            bytes32 sigIdHash = sigId.toEthSignedMessageHash();
            supervisor.checkSignatures(sigIdHash, signatures);
            SwapRequest memory request = swapRequests[_swapId];
            IYPoolVault yPoolVault = IYPoolVault(YPoolVaults[address(request.YPoolToken)]);
            uint256 value = (address(request.YPoolToken) == ETHER_ADDRESS) ? request.YPoolTokenAmount : 0;
            if (address(request.YPoolToken) != ETHER_ADDRESS) {
                request.YPoolToken.safeApprove(address(yPoolVault), request.YPoolTokenAmount);
            }
            yPoolVault.receiveAssetFromSwapper{value: value}(request.YPoolToken, request.YPoolTokenAmount, request.xyFee, request.gasFee);
            emit SwapCompleted(CompleteSwapType.Claimed, request);
        }
        /// @notice Claim the asset of multiple swap requests on source chain after YPool worker `closeSwap` on eacg target chain, by providing signatures of validators
        /// Claiming MUST be performed on source chain
        /// @dev YPool token of the swap request MUST be the same
        /// @dev Validators sign to the array of swap ids, which is different from signing for `claim`
        /// @param _swapIds Swap ids of the swap requests
        /// @param _YPoolToken Y Pool token
        /// @param signatures Signatures of validators
        function batchClaim(uint256[] calldata _swapIds, address _YPoolToken, bytes[] memory signatures) external whenNotPaused {
            require(YPoolSupportedToken[_YPoolToken], "ERR_INVALID_YPOOL_TOKEN");
            bytes32 sigId = keccak256(abi.encodePacked(supervisor.BATCH_CLAIM_IDENTIFIER(), address(this), address(swapValidatorXYChain), chainId, _swapIds));
            bytes32 sigIdHash = sigId.toEthSignedMessageHash();
            supervisor.checkSignatures(sigIdHash, signatures);
            IERC20 YPoolToken = IERC20(_YPoolToken);
            uint256 totalClaimedAmount;
            uint256 totalXYFee;
            uint256 totalGasFee;
            uint256 _startSwapId = startSwapId;
            for (uint256 i; i < _swapIds.length; i++) {
                uint256 _swapId = _swapIds[i];
                require(_startSwapId <= _swapId && _swapId < swapId, "ERR_INVALID_SWAPID");
                SwapRequest memory request = swapRequests[_swapId];
                require(request.status != RequestStatus.Closed, "ERR_ALREADY_CLOSED");
                require(request.YPoolToken == YPoolToken, "ERR_WRONG_YPOOL_TOKEN");
                totalClaimedAmount += request.YPoolTokenAmount;
                totalXYFee += request.xyFee;
                totalGasFee += request.gasFee;
                swapRequests[_swapId].status = RequestStatus.Closed;
                emit SwapCompleted(CompleteSwapType.FreeClaimed, request);
            }
            IYPoolVault yPoolVault = IYPoolVault(YPoolVaults[_YPoolToken]);
            uint256 value = (_YPoolToken == ETHER_ADDRESS) ? totalClaimedAmount : 0;
            if (_YPoolToken != ETHER_ADDRESS) {
                YPoolToken.safeApprove(address(yPoolVault), totalClaimedAmount);
            }
            yPoolVault.receiveAssetFromSwapper{value: value}(YPoolToken, totalClaimedAmount, totalXYFee, totalGasFee);
        }
        /// @notice Lock an expired swap request by providing signatures of validators
        /// Locking a swap MUST be performed on target chain to prevent YPool worker from closing an expired swap request
        /// @dev Signature collector collects signature from different validators off-chain and call this function
        /// @param fromChainId Source chain id of the swap request
        /// @param fromSwapId Swap id of the swap request
        /// @param signatures Signatures of validators
        function lockCloseSwap(uint32 fromChainId, uint256 fromSwapId, bytes[] memory signatures) external whenNotPaused {
            bytes32 universalSwapId = keccak256(abi.encodePacked(fromChainId, fromSwapId));
            require(!everClosed[universalSwapId], "ERR_ALREADY_CLOSED");
            bytes32 sigId = keccak256(abi.encodePacked(supervisor.LOCK_CLOSE_SWAP_AND_REFUND_IDENTIFIER(), address(this), fromChainId, fromSwapId));
            bytes32 sigIdHash = sigId.toEthSignedMessageHash();
            supervisor.checkSignatures(sigIdHash, signatures);
            everClosed[universalSwapId] = true;
            emit CloseSwapCompleted(CloseSwapResult.Locked, fromChainId, fromSwapId);
        }
        /// @notice Refund user if a swap request is expired or invalidated by providing signatures of validators
        /// A portion of refund will be taken away as gas fee compensation to execute the refund
        /// Refund MUST be performed on source chain
        /// @param _swapId Swap id of the swap request
        /// @param gasFeeReceiver Address that receives gas fees
        /// @param signatures Signatures of validators
        function refund(uint256 _swapId, address gasFeeReceiver, bytes[] memory signatures) external whenNotPaused {
            require(_swapId < swapId, "ERR_INVALID_SWAPID");
            require(swapRequests[_swapId].status != RequestStatus.Closed, "ERR_ALREADY_CLOSED");
            swapRequests[_swapId].status = RequestStatus.Closed;
            bytes32 sigId = keccak256(abi.encodePacked(supervisor.LOCK_CLOSE_SWAP_AND_REFUND_IDENTIFIER(), address(this), chainId, _swapId, gasFeeReceiver));
            bytes32 sigIdHash = sigId.toEthSignedMessageHash();
            supervisor.checkSignatures(sigIdHash, signatures);
            SwapRequest memory request = swapRequests[_swapId];
            (, uint256 refundGasFee) = _calculateFee(chainId, request.YPoolToken, request.YPoolTokenAmount);
            _safeTransferAsset(request.sender, request.YPoolToken, request.YPoolTokenAmount - refundGasFee);
            _safeTransferAsset(gasFeeReceiver, request.YPoolToken, refundGasFee);
            emit SwapCompleted(CompleteSwapType.Refunded, request);
        }
        /* ========== WRITE FUNCTIONS ========== */
        /// @notice This functions is called by user to initiate a swap. User swaps his/her token for YPool token on this chain and provide info for the swap on target chain. A swap request will be created for each swap.
        /// @dev swapDesc is the swap info for swapping on DEX on this chain, not the swap request
        /// @param aggregatorAdaptor The address of the adaptor of the specific dex aggregator
        /// @param swapDesc Description of the swap on DEX, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for YPool token
        /// @param toChainDesc Description of the swap on target chain, see ToChainDescription
        function swap(
            address aggregatorAdaptor,
            IDexAggregatorAdaptor.SwapDescription memory swapDesc,
            bytes memory aggregatorData,
            ToChainDescription calldata toChainDesc
        ) external payable acceptSwap whenNotPaused nonReentrant {
            _swap(aggregatorAdaptor, swapDesc, aggregatorData, toChainDesc, DEGEN_USER_IDENTIFIER);
        }
        /// @notice This functions is called by user to initiate a swap. User swaps his/her token for YPool token on this chain and provide info for the swap on target chain. A swap request will be created for each swap.
        /// @dev swapDesc is the swap info for swapping on DEX on this chain, not the swap request
        /// @param aggregatorAdaptor The address of the adaptor of the specific dex aggregator
        /// @param swapDesc Description of the swap on DEX, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for YPool token
        /// @param toChainDesc Description of the swap on target chain, see ToChainDescription
        /// @param referrer Referrer of the swap
        function swapWithReferrer(
            address aggregatorAdaptor,
            IDexAggregatorAdaptor.SwapDescription memory swapDesc,
            bytes memory aggregatorData,
            ToChainDescription calldata toChainDesc,
            address referrer
        ) external payable acceptSwap whenNotPaused nonReentrant {
            _swap(aggregatorAdaptor, swapDesc, aggregatorData, toChainDesc, referrer);
        }
        /// @notice This functions performs a single chain swap.
        /// @param aggregator The address of the dex aggregator
        /// @param swapDesc Description of the swap on dex aggregator, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for desired token
        function singleChainSwap(
            address aggregator,
            IDexAggregatorAdaptor.SwapDescription memory swapDesc,
            bytes memory aggregatorData
        ) external payable acceptSwap whenNotPaused nonReentrant {
            _singleChainSwap(aggregator, swapDesc, aggregatorData, DEGEN_USER_IDENTIFIER);
        }
        /// @notice This functions performs a single chain swap.
        /// @param aggregator The address of the dex aggregator
        /// @param swapDesc Description of the swap on dex aggregator, see IDexAggregatorAdaptor.SwapDescription
        /// @param aggregatorData Raw data consists of instructions to swap user's token for desired token
        /// @param referrer Referrer of the swap
        function singleChainSwapWithReferrer(
            address aggregator,
            IDexAggregatorAdaptor.SwapDescription memory swapDesc,
            bytes memory aggregatorData,
            address referrer
        ) external payable acceptSwap whenNotPaused nonReentrant {
            _singleChainSwap(aggregator, swapDesc, aggregatorData, referrer);
        }
        /* ========== EVENTS ========== */
        // Owner events
        event StartSwapIdSet(uint256 _swapId);
        event FeeStructureSet(uint32 _toChainId, address _YPoolToken, uint256 _gas, uint256 _min, uint256 _max, uint256 _rate, uint256 _decimals);
        event YPoolVaultSet(address _supportedToken, address _vault, bool _isSet);
        event AggregatorAdaptorSet(address _aggregator, bool _isSet);
        event AggregatorSet(address _aggregator, bool _isSet);
        event SwapValidatorXYChainSet(address _swapValidatorXYChain);
        event AcceptSwapRequestSet(bool _isSet);
        // Swap events
        event SwapRequested(uint256 _swapId, address indexed _aggregatorAdaptor, ToChainDescription _toChainDesc, IERC20 _fromToken, IERC20 indexed _YPoolToken, uint256 _YPoolTokenAmount, address _receiver, uint256 _xyFee, uint256 _gasFee, address indexed _referrer);
        event SwapCompleted(CompleteSwapType _closeType, SwapRequest _swapRequest);
        event CloseSwapCompleted(CloseSwapResult _swapResult, uint32 _fromChainId, uint256 _fromSwapId);
        event SwappedForUser(address indexed _aggregatorAdaptor, IERC20 indexed _fromToken, uint256 _fromTokenAmount, IERC20 _toToken, uint256 _toTokenAmountOut, address _receiver);
        event AggregatorSwapped(address indexed aggregator, address sender, IERC20 fromToken, IERC20 toToken, address receiver, uint256 fromTokenAmount, uint256 toTokenAmount, address indexed referrer);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            assembly {
                size := extcodesize(account)
            }
            return size > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "IAccessControlUpgradeable.sol";
    import "ContextUpgradeable.sol";
    import "StringsUpgradeable.sol";
    import "ERC165Upgradeable.sol";
    import "Initializable.sol";
    /**
     * @dev Contract module that allows children to implement role-based access
     * control mechanisms. This is a lightweight version that doesn't allow enumerating role
     * members except through off-chain means by accessing the contract event logs. Some
     * applications may benefit from on-chain enumerability, for those cases see
     * {AccessControlEnumerable}.
     *
     * Roles are referred to by their `bytes32` identifier. These should be exposed
     * in the external API and be unique. The best way to achieve this is by
     * using `public constant` hash digests:
     *
     * ```
     * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
     * ```
     *
     * Roles can be used to represent a set of permissions. To restrict access to a
     * function call, use {hasRole}:
     *
     * ```
     * function foo() public {
     *     require(hasRole(MY_ROLE, msg.sender));
     *     ...
     * }
     * ```
     *
     * Roles can be granted and revoked dynamically via the {grantRole} and
     * {revokeRole} functions. Each role has an associated admin role, and only
     * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
     *
     * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
     * that only accounts with this role will be able to grant or revoke other
     * roles. More complex role relationships can be created by using
     * {_setRoleAdmin}.
     *
     * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
     * grant and revoke this role. Extra precautions should be taken to secure
     * accounts that have been granted it.
     */
    abstract contract AccessControlUpgradeable is Initializable, ContextUpgradeable, IAccessControlUpgradeable, ERC165Upgradeable {
        function __AccessControl_init() internal initializer {
            __Context_init_unchained();
            __ERC165_init_unchained();
            __AccessControl_init_unchained();
        }
        function __AccessControl_init_unchained() internal initializer {
        }
        struct RoleData {
            mapping(address => bool) members;
            bytes32 adminRole;
        }
        mapping(bytes32 => RoleData) private _roles;
        bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
        /**
         * @dev Modifier that checks that an account has a specific role. Reverts
         * with a standardized message including the required role.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         *
         * _Available since v4.1._
         */
        modifier onlyRole(bytes32 role) {
            _checkRole(role, _msgSender());
            _;
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IAccessControlUpgradeable).interfaceId || super.supportsInterface(interfaceId);
        }
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) public view override returns (bool) {
            return _roles[role].members[account];
        }
        /**
         * @dev Revert with a standard message if `account` is missing `role`.
         *
         * The format of the revert reason is given by the following regular expression:
         *
         *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
         */
        function _checkRole(bytes32 role, address account) internal view {
            if (!hasRole(role, account)) {
                revert(
                    string(
                        abi.encodePacked(
                            "AccessControl: account ",
                            StringsUpgradeable.toHexString(uint160(account), 20),
                            " is missing role ",
                            StringsUpgradeable.toHexString(uint256(role), 32)
                        )
                    )
                );
            }
        }
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) public view override returns (bytes32) {
            return _roles[role].adminRole;
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _grantRole(role, account);
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
            _revokeRole(role, account);
        }
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) public virtual override {
            require(account == _msgSender(), "AccessControl: can only renounce roles for self");
            _revokeRole(role, account);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event. Note that unlike {grantRole}, this function doesn't perform any
         * checks on the calling account.
         *
         * [WARNING]
         * ====
         * This function should only be called from the constructor when setting
         * up the initial roles for the system.
         *
         * Using this function in any other way is effectively circumventing the admin
         * system imposed by {AccessControl}.
         * ====
         */
        function _setupRole(bytes32 role, address account) internal virtual {
            _grantRole(role, account);
        }
        /**
         * @dev Sets `adminRole` as ``role``'s admin role.
         *
         * Emits a {RoleAdminChanged} event.
         */
        function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
            bytes32 previousAdminRole = getRoleAdmin(role);
            _roles[role].adminRole = adminRole;
            emit RoleAdminChanged(role, previousAdminRole, adminRole);
        }
        function _grantRole(bytes32 role, address account) private {
            if (!hasRole(role, account)) {
                _roles[role].members[account] = true;
                emit RoleGranted(role, account, _msgSender());
            }
        }
        function _revokeRole(bytes32 role, address account) private {
            if (hasRole(role, account)) {
                _roles[role].members[account] = false;
                emit RoleRevoked(role, account, _msgSender());
            }
        }
        uint256[49] private __gap;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev External interface of AccessControl declared to support ERC165 detection.
     */
    interface IAccessControlUpgradeable {
        /**
         * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
         *
         * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
         * {RoleAdminChanged} not being emitted signaling this.
         *
         * _Available since v3.1._
         */
        event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
        /**
         * @dev Emitted when `account` is granted `role`.
         *
         * `sender` is the account that originated the contract call, an admin role
         * bearer except when using {AccessControl-_setupRole}.
         */
        event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Emitted when `account` is revoked `role`.
         *
         * `sender` is the account that originated the contract call:
         *   - if using `revokeRole`, it is the admin role bearer
         *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
         */
        event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) external view returns (bool);
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {AccessControl-_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) external view returns (bytes32);
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) external;
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "Initializable.sol";
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract ContextUpgradeable is Initializable {
        function __Context_init() internal initializer {
            __Context_init_unchained();
        }
        function __Context_init_unchained() internal initializer {
        }
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
     * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
     *
     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
     *
     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
     */
    abstract contract Initializable {
        /**
         * @dev Indicates that the contract has been initialized.
         */
        bool private _initialized;
        /**
         * @dev Indicates that the contract is in the process of being initialized.
         */
        bool private _initializing;
        /**
         * @dev Modifier to protect an initializer function from being invoked twice.
         */
        modifier initializer() {
            require(_initializing || !_initialized, "Initializable: contract is already initialized");
            bool isTopLevelCall = !_initializing;
            if (isTopLevelCall) {
                _initializing = true;
                _initialized = true;
            }
            _;
            if (isTopLevelCall) {
                _initializing = false;
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev String operations.
     */
    library StringsUpgradeable {
        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
        /**
         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
         */
        function toString(uint256 value) internal pure returns (string memory) {
            // Inspired by OraclizeAPI's implementation - MIT licence
            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
            if (value == 0) {
                return "0";
            }
            uint256 temp = value;
            uint256 digits;
            while (temp != 0) {
                digits++;
                temp /= 10;
            }
            bytes memory buffer = new bytes(digits);
            while (value != 0) {
                digits -= 1;
                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                value /= 10;
            }
            return string(buffer);
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
         */
        function toHexString(uint256 value) internal pure returns (string memory) {
            if (value == 0) {
                return "0x00";
            }
            uint256 temp = value;
            uint256 length = 0;
            while (temp != 0) {
                length++;
                temp >>= 8;
            }
            return toHexString(value, length);
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
         */
        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
            bytes memory buffer = new bytes(2 * length + 2);
            buffer[0] = "0";
            buffer[1] = "x";
            for (uint256 i = 2 * length + 1; i > 1; --i) {
                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                value >>= 4;
            }
            require(value == 0, "Strings: hex length insufficient");
            return string(buffer);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "IERC165Upgradeable.sol";
    import "Initializable.sol";
    /**
     * @dev Implementation of the {IERC165} interface.
     *
     * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
     * for the additional interface id that will be supported. For example:
     *
     * ```solidity
     * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
     *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
     * }
     * ```
     *
     * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
     */
    abstract contract ERC165Upgradeable is Initializable, IERC165Upgradeable {
        function __ERC165_init() internal initializer {
            __ERC165_init_unchained();
        }
        function __ERC165_init_unchained() internal initializer {
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IERC165Upgradeable).interfaceId;
        }
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC165 standard, as defined in the
     * https://eips.ethereum.org/EIPS/eip-165[EIP].
     *
     * Implementers can declare support of contract interfaces, which can then be
     * queried by others ({ERC165Checker}).
     *
     * For an implementation, see {ERC165}.
     */
    interface IERC165Upgradeable {
        /**
         * @dev Returns true if this contract implements the interface defined by
         * `interfaceId`. See the corresponding
         * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
         * to learn more about how these ids are created.
         *
         * This function call must use less than 30 000 gas.
         */
        function supportsInterface(bytes4 interfaceId) external view returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "ERC1967UpgradeUpgradeable.sol";
    import "Initializable.sol";
    /**
     * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
     * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
     *
     * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
     * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
     * `UUPSUpgradeable` with a custom implementation of upgrades.
     *
     * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
     *
     * _Available since v4.1._
     */
    abstract contract UUPSUpgradeable is Initializable, ERC1967UpgradeUpgradeable {
        function __UUPSUpgradeable_init() internal initializer {
            __ERC1967Upgrade_init_unchained();
            __UUPSUpgradeable_init_unchained();
        }
        function __UUPSUpgradeable_init_unchained() internal initializer {
        }
        /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
        address private immutable __self = address(this);
        /**
         * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
         * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
         * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
         * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
         * fail.
         */
        modifier onlyProxy() {
            require(address(this) != __self, "Function must be called through delegatecall");
            require(_getImplementation() == __self, "Function must be called through active proxy");
            _;
        }
        /**
         * @dev Upgrade the implementation of the proxy to `newImplementation`.
         *
         * Calls {_authorizeUpgrade}.
         *
         * Emits an {Upgraded} event.
         */
        function upgradeTo(address newImplementation) external virtual onlyProxy {
            _authorizeUpgrade(newImplementation);
            _upgradeToAndCallSecure(newImplementation, new bytes(0), false);
        }
        /**
         * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
         * encoded in `data`.
         *
         * Calls {_authorizeUpgrade}.
         *
         * Emits an {Upgraded} event.
         */
        function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
            _authorizeUpgrade(newImplementation);
            _upgradeToAndCallSecure(newImplementation, data, true);
        }
        /**
         * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
         * {upgradeTo} and {upgradeToAndCall}.
         *
         * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
         *
         * ```solidity
         * function _authorizeUpgrade(address) internal override onlyOwner {}
         * ```
         */
        function _authorizeUpgrade(address newImplementation) internal virtual;
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.2;
    import "IBeaconUpgradeable.sol";
    import "AddressUpgradeable.sol";
    import "StorageSlotUpgradeable.sol";
    import "Initializable.sol";
    /**
     * @dev This abstract contract provides getters and event emitting update functions for
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
     *
     * _Available since v4.1._
     *
     * @custom:oz-upgrades-unsafe-allow delegatecall
     */
    abstract contract ERC1967UpgradeUpgradeable is Initializable {
        function __ERC1967Upgrade_init() internal initializer {
            __ERC1967Upgrade_init_unchained();
        }
        function __ERC1967Upgrade_init_unchained() internal initializer {
        }
        // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
        bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
        /**
         * @dev Storage slot with the address of the current implementation.
         * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
        /**
         * @dev Emitted when the implementation is upgraded.
         */
        event Upgraded(address indexed implementation);
        /**
         * @dev Returns the current implementation address.
         */
        function _getImplementation() internal view returns (address) {
            return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 implementation slot.
         */
        function _setImplementation(address newImplementation) private {
            require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
            StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
        }
        /**
         * @dev Perform implementation upgrade
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeTo(address newImplementation) internal {
            _setImplementation(newImplementation);
            emit Upgraded(newImplementation);
        }
        /**
         * @dev Perform implementation upgrade with additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCall(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            _upgradeTo(newImplementation);
            if (data.length > 0 || forceCall) {
                _functionDelegateCall(newImplementation, data);
            }
        }
        /**
         * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCallSecure(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            address oldImplementation = _getImplementation();
            // Initial upgrade and setup call
            _setImplementation(newImplementation);
            if (data.length > 0 || forceCall) {
                _functionDelegateCall(newImplementation, data);
            }
            // Perform rollback test if not already in progress
            StorageSlotUpgradeable.BooleanSlot storage rollbackTesting = StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT);
            if (!rollbackTesting.value) {
                // Trigger rollback using upgradeTo from the new implementation
                rollbackTesting.value = true;
                _functionDelegateCall(
                    newImplementation,
                    abi.encodeWithSignature("upgradeTo(address)", oldImplementation)
                );
                rollbackTesting.value = false;
                // Check rollback was effective
                require(oldImplementation == _getImplementation(), "ERC1967Upgrade: upgrade breaks further upgrades");
                // Finally reset to the new implementation and log the upgrade
                _upgradeTo(newImplementation);
            }
        }
        /**
         * @dev Storage slot with the admin of the contract.
         * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
        /**
         * @dev Emitted when the admin account has changed.
         */
        event AdminChanged(address previousAdmin, address newAdmin);
        /**
         * @dev Returns the current admin.
         */
        function _getAdmin() internal view returns (address) {
            return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 admin slot.
         */
        function _setAdmin(address newAdmin) private {
            require(newAdmin != address(0), "ERC1967: new admin is the zero address");
            StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
        }
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _changeAdmin(address newAdmin) internal {
            emit AdminChanged(_getAdmin(), newAdmin);
            _setAdmin(newAdmin);
        }
        /**
         * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
         * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
         */
        bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
        /**
         * @dev Emitted when the beacon is upgraded.
         */
        event BeaconUpgraded(address indexed beacon);
        /**
         * @dev Returns the current beacon.
         */
        function _getBeacon() internal view returns (address) {
            return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
        }
        /**
         * @dev Stores a new beacon in the EIP1967 beacon slot.
         */
        function _setBeacon(address newBeacon) private {
            require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
            require(
                AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                "ERC1967: beacon implementation is not a contract"
            );
            StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
        }
        /**
         * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
         * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
         *
         * Emits a {BeaconUpgraded} event.
         */
        function _upgradeBeaconToAndCall(
            address newBeacon,
            bytes memory data,
            bool forceCall
        ) internal {
            _setBeacon(newBeacon);
            emit BeaconUpgraded(newBeacon);
            if (data.length > 0 || forceCall) {
                _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
            }
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
            require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
        }
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev This is the interface that {BeaconProxy} expects of its beacon.
     */
    interface IBeaconUpgradeable {
        /**
         * @dev Must return an address that can be used as a delegate call target.
         *
         * {BeaconProxy} will check that this address is a contract.
         */
        function implementation() external view returns (address);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library AddressUpgradeable {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            assembly {
                size := extcodesize(account)
            }
            return size > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCall(target, data, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Library for reading and writing primitive types to specific storage slots.
     *
     * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
     * This library helps with reading and writing to such slots without the need for inline assembly.
     *
     * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
     *
     * Example usage to set ERC1967 implementation slot:
     * ```
     * contract ERC1967 {
     *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
     *
     *     function _getImplementation() internal view returns (address) {
     *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
     *     }
     *
     *     function _setImplementation(address newImplementation) internal {
     *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
     *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
     *     }
     * }
     * ```
     *
     * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
     */
    library StorageSlotUpgradeable {
        struct AddressSlot {
            address value;
        }
        struct BooleanSlot {
            bool value;
        }
        struct Bytes32Slot {
            bytes32 value;
        }
        struct Uint256Slot {
            uint256 value;
        }
        /**
         * @dev Returns an `AddressSlot` with member `value` located at `slot`.
         */
        function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
         */
        function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
         */
        function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
         */
        function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
            assembly {
                r.slot := slot
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "ContextUpgradeable.sol";
    import "Initializable.sol";
    /**
     * @dev Contract module which allows children to implement an emergency stop
     * mechanism that can be triggered by an authorized account.
     *
     * This module is used through inheritance. It will make available the
     * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
     * the functions of your contract. Note that they will not be pausable by
     * simply including this module, only once the modifiers are put in place.
     */
    abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
        /**
         * @dev Emitted when the pause is triggered by `account`.
         */
        event Paused(address account);
        /**
         * @dev Emitted when the pause is lifted by `account`.
         */
        event Unpaused(address account);
        bool private _paused;
        /**
         * @dev Initializes the contract in unpaused state.
         */
        function __Pausable_init() internal initializer {
            __Context_init_unchained();
            __Pausable_init_unchained();
        }
        function __Pausable_init_unchained() internal initializer {
            _paused = false;
        }
        /**
         * @dev Returns true if the contract is paused, and false otherwise.
         */
        function paused() public view virtual returns (bool) {
            return _paused;
        }
        /**
         * @dev Modifier to make a function callable only when the contract is not paused.
         *
         * Requirements:
         *
         * - The contract must not be paused.
         */
        modifier whenNotPaused() {
            require(!paused(), "Pausable: paused");
            _;
        }
        /**
         * @dev Modifier to make a function callable only when the contract is paused.
         *
         * Requirements:
         *
         * - The contract must be paused.
         */
        modifier whenPaused() {
            require(paused(), "Pausable: not paused");
            _;
        }
        /**
         * @dev Triggers stopped state.
         *
         * Requirements:
         *
         * - The contract must not be paused.
         */
        function _pause() internal virtual whenNotPaused {
            _paused = true;
            emit Paused(_msgSender());
        }
        /**
         * @dev Returns to normal state.
         *
         * Requirements:
         *
         * - The contract must be paused.
         */
        function _unpause() internal virtual whenPaused {
            _paused = false;
            emit Unpaused(_msgSender());
        }
        uint256[49] private __gap;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "IERC20.sol";
    import "IERC20Metadata.sol";
    import "Context.sol";
    /**
     * @dev Implementation of the {IERC20} interface.
     *
     * This implementation is agnostic to the way tokens are created. This means
     * that a supply mechanism has to be added in a derived contract using {_mint}.
     * For a generic mechanism see {ERC20PresetMinterPauser}.
     *
     * TIP: For a detailed writeup see our guide
     * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * We have followed general OpenZeppelin Contracts guidelines: functions revert
     * instead returning `false` on failure. This behavior is nonetheless
     * conventional and does not conflict with the expectations of ERC20
     * applications.
     *
     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
     * This allows applications to reconstruct the allowance for all accounts just
     * by listening to said events. Other implementations of the EIP may not emit
     * these events, as it isn't required by the specification.
     *
     * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
     * functions have been added to mitigate the well-known issues around setting
     * allowances. See {IERC20-approve}.
     */
    contract ERC20 is Context, IERC20, IERC20Metadata {
        mapping(address => uint256) private _balances;
        mapping(address => mapping(address => uint256)) private _allowances;
        uint256 private _totalSupply;
        string private _name;
        string private _symbol;
        /**
         * @dev Sets the values for {name} and {symbol}.
         *
         * The default value of {decimals} is 18. To select a different value for
         * {decimals} you should overload it.
         *
         * All two of these values are immutable: they can only be set once during
         * construction.
         */
        constructor(string memory name_, string memory symbol_) {
            _name = name_;
            _symbol = symbol_;
        }
        /**
         * @dev Returns the name of the token.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
        /**
         * @dev Returns the symbol of the token, usually a shorter version of the
         * name.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
        /**
         * @dev Returns the number of decimals used to get its user representation.
         * For example, if `decimals` equals `2`, a balance of `505` tokens should
         * be displayed to a user as `5.05` (`505 / 10 ** 2`).
         *
         * Tokens usually opt for a value of 18, imitating the relationship between
         * Ether and Wei. This is the value {ERC20} uses, unless this function is
         * overridden;
         *
         * NOTE: This information is only used for _display_ purposes: it in
         * no way affects any of the arithmetic of the contract, including
         * {IERC20-balanceOf} and {IERC20-transfer}.
         */
        function decimals() public view virtual override returns (uint8) {
            return 18;
        }
        /**
         * @dev See {IERC20-totalSupply}.
         */
        function totalSupply() public view virtual override returns (uint256) {
            return _totalSupply;
        }
        /**
         * @dev See {IERC20-balanceOf}.
         */
        function balanceOf(address account) public view virtual override returns (uint256) {
            return _balances[account];
        }
        /**
         * @dev See {IERC20-transfer}.
         *
         * Requirements:
         *
         * - `recipient` cannot be the zero address.
         * - the caller must have a balance of at least `amount`.
         */
        function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
            _transfer(_msgSender(), recipient, amount);
            return true;
        }
        /**
         * @dev See {IERC20-allowance}.
         */
        function allowance(address owner, address spender) public view virtual override returns (uint256) {
            return _allowances[owner][spender];
        }
        /**
         * @dev See {IERC20-approve}.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function approve(address spender, uint256 amount) public virtual override returns (bool) {
            _approve(_msgSender(), spender, amount);
            return true;
        }
        /**
         * @dev See {IERC20-transferFrom}.
         *
         * Emits an {Approval} event indicating the updated allowance. This is not
         * required by the EIP. See the note at the beginning of {ERC20}.
         *
         * Requirements:
         *
         * - `sender` and `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         * - the caller must have allowance for ``sender``'s tokens of at least
         * `amount`.
         */
        function transferFrom(
            address sender,
            address recipient,
            uint256 amount
        ) public virtual override returns (bool) {
            _transfer(sender, recipient, amount);
            uint256 currentAllowance = _allowances[sender][_msgSender()];
            require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
            unchecked {
                _approve(sender, _msgSender(), currentAllowance - amount);
            }
            return true;
        }
        /**
         * @dev Atomically increases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
            _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
            return true;
        }
        /**
         * @dev Atomically decreases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `spender` must have allowance for the caller of at least
         * `subtractedValue`.
         */
        function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
            uint256 currentAllowance = _allowances[_msgSender()][spender];
            require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
            unchecked {
                _approve(_msgSender(), spender, currentAllowance - subtractedValue);
            }
            return true;
        }
        /**
         * @dev Moves `amount` of tokens from `sender` to `recipient`.
         *
         * This internal function is equivalent to {transfer}, and can be used to
         * e.g. implement automatic token fees, slashing mechanisms, etc.
         *
         * Emits a {Transfer} event.
         *
         * Requirements:
         *
         * - `sender` cannot be the zero address.
         * - `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         */
        function _transfer(
            address sender,
            address recipient,
            uint256 amount
        ) internal virtual {
            require(sender != address(0), "ERC20: transfer from the zero address");
            require(recipient != address(0), "ERC20: transfer to the zero address");
            _beforeTokenTransfer(sender, recipient, amount);
            uint256 senderBalance = _balances[sender];
            require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
            unchecked {
                _balances[sender] = senderBalance - amount;
            }
            _balances[recipient] += amount;
            emit Transfer(sender, recipient, amount);
            _afterTokenTransfer(sender, recipient, amount);
        }
        /** @dev Creates `amount` tokens and assigns them to `account`, increasing
         * the total supply.
         *
         * Emits a {Transfer} event with `from` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         */
        function _mint(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: mint to the zero address");
            _beforeTokenTransfer(address(0), account, amount);
            _totalSupply += amount;
            _balances[account] += amount;
            emit Transfer(address(0), account, amount);
            _afterTokenTransfer(address(0), account, amount);
        }
        /**
         * @dev Destroys `amount` tokens from `account`, reducing the
         * total supply.
         *
         * Emits a {Transfer} event with `to` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - `account` must have at least `amount` tokens.
         */
        function _burn(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: burn from the zero address");
            _beforeTokenTransfer(account, address(0), amount);
            uint256 accountBalance = _balances[account];
            require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
            unchecked {
                _balances[account] = accountBalance - amount;
            }
            _totalSupply -= amount;
            emit Transfer(account, address(0), amount);
            _afterTokenTransfer(account, address(0), amount);
        }
        /**
         * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
         *
         * This internal function is equivalent to `approve`, and can be used to
         * e.g. set automatic allowances for certain subsystems, etc.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `owner` cannot be the zero address.
         * - `spender` cannot be the zero address.
         */
        function _approve(
            address owner,
            address spender,
            uint256 amount
        ) internal virtual {
            require(owner != address(0), "ERC20: approve from the zero address");
            require(spender != address(0), "ERC20: approve to the zero address");
            _allowances[owner][spender] = amount;
            emit Approval(owner, spender, amount);
        }
        /**
         * @dev Hook that is called before any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * will be transferred to `to`.
         * - when `from` is zero, `amount` tokens will be minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(
            address from,
            address to,
            uint256 amount
        ) internal virtual {}
        /**
         * @dev Hook that is called after any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * has been transferred to `to`.
         * - when `from` is zero, `amount` tokens have been minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _afterTokenTransfer(
            address from,
            address to,
            uint256 amount
        ) internal virtual {}
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address sender,
            address recipient,
            uint256 amount
        ) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "IERC20.sol";
    /**
     * @dev Interface for the optional metadata functions from the ERC20 standard.
     *
     * _Available since v4.1._
     */
    interface IERC20Metadata is IERC20 {
        /**
         * @dev Returns the name of the token.
         */
        function name() external view returns (string memory);
        /**
         * @dev Returns the symbol of the token.
         */
        function symbol() external view returns (string memory);
        /**
         * @dev Returns the decimals places of the token.
         */
        function decimals() external view returns (uint8);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    /**
     * @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 {
        enum RecoverError {
            NoError,
            InvalidSignature,
            InvalidSignatureLength,
            InvalidSignatureS,
            InvalidSignatureV
        }
        function _throwError(RecoverError error) private pure {
            if (error == RecoverError.NoError) {
                return; // no error: do nothing
            } else if (error == RecoverError.InvalidSignature) {
                revert("ECDSA: invalid signature");
            } else if (error == RecoverError.InvalidSignatureLength) {
                revert("ECDSA: invalid signature length");
            } else if (error == RecoverError.InvalidSignatureS) {
                revert("ECDSA: invalid signature 's' value");
            } else if (error == RecoverError.InvalidSignatureV) {
                revert("ECDSA: invalid signature 'v' value");
            }
        }
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with
         * `signature` or error string. This address can then be used for verification purposes.
         *
         * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {toEthSignedMessageHash} on it.
         *
         * Documentation for signature generation:
         * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
         * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
         *
         * _Available since v4.3._
         */
        function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
            // Check the signature length
            // - case 65: r,s,v signature (standard)
            // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
            if (signature.length == 65) {
                bytes32 r;
                bytes32 s;
                uint8 v;
                // ecrecover takes the signature parameters, and the only way to get them
                // currently is to use assembly.
                assembly {
                    r := mload(add(signature, 0x20))
                    s := mload(add(signature, 0x40))
                    v := byte(0, mload(add(signature, 0x60)))
                }
                return tryRecover(hash, v, r, s);
            } else if (signature.length == 64) {
                bytes32 r;
                bytes32 vs;
                // ecrecover takes the signature parameters, and the only way to get them
                // currently is to use assembly.
                assembly {
                    r := mload(add(signature, 0x20))
                    vs := mload(add(signature, 0x40))
                }
                return tryRecover(hash, r, vs);
            } else {
                return (address(0), RecoverError.InvalidSignatureLength);
            }
        }
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with
         * `signature`. This address can then be used for verification purposes.
         *
         * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {toEthSignedMessageHash} on it.
         */
        function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
            (address recovered, RecoverError error) = tryRecover(hash, signature);
            _throwError(error);
            return recovered;
        }
        /**
         * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
         *
         * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
         *
         * _Available since v4.3._
         */
        function tryRecover(
            bytes32 hash,
            bytes32 r,
            bytes32 vs
        ) internal pure returns (address, RecoverError) {
            bytes32 s;
            uint8 v;
            assembly {
                s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                v := add(shr(255, vs), 27)
            }
            return tryRecover(hash, v, r, s);
        }
        /**
         * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
         *
         * _Available since v4.2._
         */
        function recover(
            bytes32 hash,
            bytes32 r,
            bytes32 vs
        ) internal pure returns (address) {
            (address recovered, RecoverError error) = tryRecover(hash, r, vs);
            _throwError(error);
            return recovered;
        }
        /**
         * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
         * `r` and `s` signature fields separately.
         *
         * _Available since v4.3._
         */
        function tryRecover(
            bytes32 hash,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal pure returns (address, RecoverError) {
            // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
            // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
            // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
            // signatures from current libraries generate a unique signature with an s-value in the lower half order.
            //
            // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
            // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
            // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
            // these malleable signatures as well.
            if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
                return (address(0), RecoverError.InvalidSignatureS);
            }
            if (v != 27 && v != 28) {
                return (address(0), RecoverError.InvalidSignatureV);
            }
            // If the signature is valid (and not malleable), return the signer address
            address signer = ecrecover(hash, v, r, s);
            if (signer == address(0)) {
                return (address(0), RecoverError.InvalidSignature);
            }
            return (signer, RecoverError.NoError);
        }
        /**
         * @dev Overload of {ECDSA-recover} that receives the `v`,
         * `r` and `s` signature fields separately.
         */
        function recover(
            bytes32 hash,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal pure returns (address) {
            (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
            _throwError(error);
            return recovered;
        }
        /**
         * @dev Returns an Ethereum Signed Message, created from a `hash`. This
         * produces hash corresponding to the one signed with the
         * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
         * JSON-RPC method as part of EIP-191.
         *
         * See {recover}.
         */
        function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
            // 32 is the length in bytes of hash,
            // enforced by the type signature above
            return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
    32", hash));
        }
        /**
         * @dev Returns an Ethereum Signed Typed Data, created from a
         * `domainSeparator` and a `structHash`. This produces hash corresponding
         * to the one signed with the
         * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
         * JSON-RPC method as part of EIP-712.
         *
         * See {recover}.
         */
        function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
            return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.8.0;
    import "IERC20.sol";
    import "Address.sol";
    /**
     * @title SafeERC20
     * @dev Wrappers around ERC20 operations that throw on failure (when the token
     * contract returns false). Tokens that return no value (and instead revert or
     * throw on failure) are also supported, non-reverting calls are assumed to be
     * successful.
     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
     */
    library SafeERC20 {
        using Address for address;
        function safeTransfer(
            IERC20 token,
            address to,
            uint256 value
        ) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
        }
        function safeTransferFrom(
            IERC20 token,
            address from,
            address to,
            uint256 value
        ) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
        }
        /**
         * @dev Deprecated. This function has issues similar to the ones found in
         * {IERC20-approve}, and its usage is discouraged.
         *
         * Whenever possible, use {safeIncreaseAllowance} and
         * {safeDecreaseAllowance} instead.
         */
        function safeApprove(
            IERC20 token,
            address spender,
            uint256 value
        ) internal {
            // safeApprove should only be called when setting an initial allowance,
            // or when resetting it to zero. To increase and decrease it, use
            // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
            require(
                (value == 0) || (token.allowance(address(this), spender) == 0),
                "SafeERC20: approve from non-zero to non-zero allowance"
            );
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
        }
        function safeIncreaseAllowance(
            IERC20 token,
            address spender,
            uint256 value
        ) internal {
            uint256 newAllowance = token.allowance(address(this), spender) + value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
        function safeDecreaseAllowance(
            IERC20 token,
            address spender,
            uint256 value
        ) internal {
            unchecked {
                uint256 oldAllowance = token.allowance(address(this), spender);
                require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                uint256 newAllowance = oldAllowance - value;
                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
            }
        }
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         */
        function _callOptionalReturn(IERC20 token, bytes memory data) private {
            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
            // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
            // the target address contains contract code and also asserts for success in the low-level call.
            bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
            if (returndata.length > 0) {
                // Return data is optional
                require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^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() {
            _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: BUSL-1.1
    pragma solidity 0.8.2;
    import "ECDSA.sol";
    /// @title Supervisor is the guardian of YPool. It requires multiple validators to valid
    /// the requests from users and workers and sign on them if valid.
    contract Supervisor {
        using ECDSA for bytes32;
        /* ========== STATE VARIABLES ========== */
        bytes32 public constant CLAIM_IDENTIFIER = 'SWAPPER_CLAIM';
        bytes32 public constant SET_THRESHOLD_IDENTIFIER = 'SET_THRESHOLD';
        bytes32 public constant SET_VALIDATOR_IDENTIFIER = 'SET_VALIDATOR';
        bytes32 public constant LOCK_CLOSE_SWAP_AND_REFUND_IDENTIFIER = 'LOCK_CLOSE_SWAP_AND_REFUND';
        bytes32 public constant BATCH_CLAIM_IDENTIFIER = 'BATCH_CLAIM';
        bytes32 public constant VALIDATE_SWAP_IDENTIFIER = 'VALIDATE_SWAP_IDENTIFIER';
        bytes32 public constant VALIDATE_XY_CROSS_CHAIN_IDENTIFIER = 'VALIDATE_XY_XCHAIN_IDENTIFIER';
        // the chain ID contract located at
        uint32 public chainId;
        // check if the address is one of the validators
        mapping (address => bool) public validators;
        // number of validators
        uint256 private validatorsNum;
        // threshold to pass the signature validation
        uint256 public threshold;
        // current nonce for write functions
        uint256 public nonce;
        /// @dev Constuctor with chainId / validators / threshold
        /// @param _chainId The chain ID located with
        /// @param _validators Initial validator addresses
        /// @param _threshold Initial threshold to pass the request validation
        constructor(uint32 _chainId, address [] memory _validators, uint256 _threshold) {
            chainId = _chainId;
            for (uint256 i; i < _validators.length; i++) {
                validators[_validators[i]] = true;
            }
            validatorsNum = _validators.length;
            require(_threshold <= validatorsNum, "ERR_INVALID_THRESHOLD");
            threshold = _threshold;
        }
        /* ========== VIEW FUNCTIONS ========== */
        /// @notice Check if there are enough signed signatures to the signature hash
        /// @param sigIdHash The signature hash to be signed
        /// @param signatures Signed signatures by different validators
        function checkSignatures(bytes32 sigIdHash, bytes[] memory signatures) public view {
            require(signatures.length >= threshold, "ERR_NOT_ENOUGH_SIGNATURES");
            address prevAddress = address(0);
            for (uint i; i < threshold; i++) {
                address recovered = sigIdHash.recover(signatures[i]);
                require(validators[recovered], "ERR_NOT_VALIDATOR");
                require(recovered > prevAddress, "ERR_WRONG_SIGNER_ORDER");
                prevAddress = recovered;
            }
        }
        /* ========== WRITE FUNCTIONS ========== */
        /// @notice Change `threshold` by providing a correct nonce and enough signatures from validators
        /// @param _threshold New `threshold`
        /// @param _nonce The nonce to be processed
        /// @param signatures Signed signatures by validators
        function setThreshold(uint256 _threshold, uint256 _nonce, bytes[] memory signatures) external {
            require(signatures.length >= threshold, "ERR_NOT_ENOUGH_SIGNATURES");
            require(_nonce == nonce, "ERR_INVALID_NONCE");
            require(_threshold > 0, "ERR_INVALID_THRESHOLD");
            require(_threshold <= validatorsNum, "ERR_INVALID_THRESHOLD");
            bytes32 sigId = keccak256(abi.encodePacked(SET_THRESHOLD_IDENTIFIER, address(this), chainId, _threshold, _nonce));
            bytes32 sigIdHash = sigId.toEthSignedMessageHash();
            checkSignatures(sigIdHash, signatures);
            threshold = _threshold;
            nonce++;
        }
        /// @notice Set / remove the validator address to be part of signatures committee
        /// @param _validator The address to add or remove
        /// @param flag `true` to add, `false` to remove
        /// @param _nonce The nonce to be processed
        /// @param signatures Signed signatures by validators
        function setValidator(address _validator, bool flag, uint256 _nonce, bytes[] memory signatures) external {
            require(_validator != address(0), "ERR_INVALID_VALIDATOR");
            require(signatures.length >= threshold, "ERR_NOT_ENOUGH_SIGNATURES");
            require(_nonce == nonce, "ERR_INVALID_NONCE");
            require(flag != validators[_validator], "ERR_OPERATION_TO_VALIDATOR");
            bytes32 sigId = keccak256(abi.encodePacked(SET_VALIDATOR_IDENTIFIER, address(this), chainId, _validator, flag, _nonce));
            bytes32 sigIdHash = sigId.toEthSignedMessageHash();
            checkSignatures(sigIdHash, signatures);
            if (validators[_validator]) {
                validatorsNum--;
                validators[_validator] = false;
                if (validatorsNum < threshold) threshold--;
            } else {
                validatorsNum++;
                validators[_validator] = true;
            }
            nonce++;
        }
    }
    // SPDX-License-Identifier: BUSL-1.1
    pragma solidity 0.8.2;
    pragma experimental ABIEncoderV2;
    import { IERC20 } from "ERC20.sol";
    interface IDexAggregatorAdaptor {
        struct SwapDescription {
            IERC20 fromToken;
            IERC20 toToken;
            address receiver;
            uint256 amount;
            uint256 minReturnAmount;
        }
        // spec:
        //    (revert if any of the following steps fails)
        //    1. IDexAggregatorAdaptor receives `amountIn` `fromToken` where `amountIn >= amount`.
        //    2. IDexAggregatorAdaptor receives `amountOut` `toToken` where `amountOut >= minReturnAmount`.
        //    3. `receiver` receives `amountOut` `toToken`.
        function swap(SwapDescription calldata desc, bytes calldata data) external payable returns (uint256 returnAmount);
    }
    // SPDX-License-Identifier: BUSL-1.1
    pragma solidity 0.8.2;
    import { IERC20 } from "ERC20.sol";
    interface IYPoolVault {
        function transferToSwapper(IERC20 token, uint256 amount) external;
        function receiveAssetFromSwapper(IERC20 token, uint256 amount, uint256 xyFeeAmount, uint256 gasFeeAmount) external payable;
    }