// File: contracts/bridges/StargateAdapter.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity >=0.8.15;

import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

import "../interfaces/IBridgeAdapter.sol";
import "../interfaces/IBridgeStargate.sol";
import "../interfaces/ITransferSwapper.sol";
import "../interfaces/IWETH.sol";

contract StargateAdapter is IBridgeAdapter, Ownable {
    using SafeERC20 for IERC20;
    
    address public mainContract;
    mapping(address => bool) public supportedRouters;
    mapping(bytes32 => bool) public transfers;

    event MainContractUpdated(address mainContract);
    event SupportedRouterUpdated(address router, bool enabled);

    modifier onlyMainContract() {
        require(msg.sender == mainContract, "caller is not main contract");
        _;
    }

    constructor(address _mainContract, address[] memory _routers) {
        mainContract = _mainContract;
        for (uint256 i = 0; i < _routers.length; i++) {
            require(_routers[i] != address(0), "nop");
            supportedRouters[_routers[i]] = true;
        }
    }

    struct StargateParams {
        // a unique identifier that is uses to dedup transfers
        // this value is the a timestamp sent from frontend, but in theory can be any unique number
        uint64 nonce;
        uint256 srcPoolId;
        uint256 dstPoolId;
        uint256 minReceivedAmt; // defines the slippage, the min qty you would accept on the destination
        uint16 stargateDstChainId; // stargate defines chain id in its way
        address router; // the target router, should be in the <ref>supportedRouters</ref>
    }

    function bridge(
        uint64 _dstChainId,
        address _receiver,
        uint256 _amount,
        address _token,
        bytes memory _bridgeParams,
        bytes memory //_requestMessage // Not used for now, as stargate messaging is not supported in this version
    ) external payable onlyMainContract returns (bytes memory bridgeResp) {
        StargateParams memory params = abi.decode((_bridgeParams), (StargateParams));
        require(supportedRouters[params.router], "illegal router");
        
        bytes32 transferId = keccak256(
            abi.encodePacked(_receiver, _token, _amount, _dstChainId, params.nonce, uint64(block.chainid))
        );
        require(transfers[transferId] == false, "transfer exists");
        transfers[transferId] = true;
        IERC20(_token).safeTransferFrom(msg.sender, address(this), _amount);
        uint64 outboundNonce = swap(_token, _receiver, _amount, params);
        return abi.encodePacked(outboundNonce);
    }

    function swap(
        address _token, 
        address _receiver,
        uint256 _amount,
        StargateParams memory params) private returns (uint64 outboundNonce) {
        IBridgeStargate router = IBridgeStargate(params.router);
        ITransferSwapper main = ITransferSwapper(mainContract);
        if (_token == main.nativeWrap()) {
            IWETH(_token).withdraw(_amount);
            router.swapETH{value: msg.value + _amount}(
                params.stargateDstChainId, 
                payable(mainContract),
                abi.encodePacked(_receiver), 
                _amount, 
                params.minReceivedAmt);
        } else {
            IERC20(_token).safeApprove(params.router, _amount);
            router.swap{value: msg.value}(
                params.stargateDstChainId, 
                params.srcPoolId, 
                params.dstPoolId, 
                payable(mainContract), // default to refund to main contract
                _amount,
                params.minReceivedAmt, 
                IBridgeStargate.lzTxObj(0, 0, "0x"), 
                abi.encodePacked(_receiver), 
                bytes("") // not supported additional msg in this version
            );
            IERC20(_token).safeApprove(params.router, 0);
        }

        // query current nonce
        address stargateInternalBridge;
        if (_token == main.nativeWrap()) {
            stargateInternalBridge = IBridgeStargate(router.stargateRouter()).bridge();
        } else {
            stargateInternalBridge = router.bridge();
        }
        address layerZeroEndpoint = IStargateInternalBridge(stargateInternalBridge).layerZeroEndpoint();
        outboundNonce = ILayerZeroEndpoint(layerZeroEndpoint).getOutboundNonce(params.stargateDstChainId, stargateInternalBridge);
    }

    function updateMainContract(address _mainContract) external onlyOwner {
        mainContract = _mainContract;
        emit MainContractUpdated(_mainContract);
    }

    function setSupportedRouter(address _router, bool _enabled) external onlyOwner {
        bool enabled = supportedRouters[_router];
        require(enabled != _enabled, "nop");
        supportedRouters[_router] = _enabled;
        emit SupportedRouterUpdated(_router, _enabled);
    }

    // This is needed to receive ETH when calling `IWETH.withdraw`
    receive() external payable {}
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/draft-IERC20Permit.sol";
import "../../../utils/Address.sol";

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

    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));
        }
    }

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

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

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

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

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

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

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

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: contracts/interfaces/IBridgeAdapter.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity >=0.8.15;

interface IBridgeAdapter {
    function bridge(
        uint64 _dstChainId,
        // the address that the fund is transfered to on the destination chain
        address _receiver,
        uint256 _amount,
        address _token,
        // Bridge transfers quoted and abi encoded by chainhop backend server.
        // Bridge adapter implementations need to decode this themselves.
        bytes memory _bridgeParams,
        // The message to be bridged alongside the transfer.
        // Note if the bridge adapter doesn't support message passing, the call should revert when
        // this field is set.
        bytes memory _requestMessage
    ) external payable returns (bytes memory bridgeResp);
}

// File: contracts/interfaces/IBridgeStargate.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity >=0.8.15;

interface IBridgeStargate {
    struct lzTxObj {
        uint256 dstGasForCall;
        uint256 dstNativeAmount;
        bytes dstNativeAddr;
    }

    // only in non RouterETH
    function swap(
        uint16 _dstChainId,
        uint256 _srcPoolId,
        uint256 _dstPoolId,
        address payable _refundAddress,
        uint256 _amountLD,
        uint256 _minAmountLD,
        lzTxObj memory _lzTxParams,
        bytes calldata _to,
        bytes calldata _payload
    ) external payable;
    // only in non RouterETH
    function bridge() external pure returns (address);

    // only in RouterETH
    function swapETH(
        uint16 _dstChainId,                         // destination Stargate chainId
        address payable _refundAddress,             // refund additional messageFee to this address
        bytes calldata _toAddress,                  // the receiver of the destination ETH
        uint256 _amountLD,                          // the amount, in Local Decimals, to be swapped
        uint256 _minAmountLD                        // the minimum amount accepted out on destination
    ) external payable;
    // only in RouterETH
    function stargateRouter() external pure returns (address);
}

interface IStargateInternalBridge {
    function layerZeroEndpoint() external pure returns (address);
}

interface ILayerZeroEndpoint {
    function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
}

// File: contracts/interfaces/ITransferSwapper.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity >=0.8.15;

import "./IMessageReceiverApp.sol";

interface ITransferSwapper {
    function nativeWrap() external view returns (address);

    /**
     * @notice Called by MessageBus (MessageBusReceiver) to process refund of the original transfer from this contract
     * @param _token The token address of the original transfer
     * @param _amount The amount of the original transfer
     * @param _message The same message associated with the original transfer
     * @param _executor Address who called the MessageBus execution function
     */
    function executeMessageWithTransferRefundFromAdapter(
        address _token,
        uint256 _amount,
        bytes calldata _message,
        address _executor
    ) external payable returns (IMessageReceiverApp.ExecutionStatus);
}

// File: contracts/interfaces/IWETH.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity >=0.8.15;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

interface IWETH is IERC20 {
    function deposit() external payable;

    function withdraw(uint256) external;
}

// File: @openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

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

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

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

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

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

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return 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
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

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



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

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;
    }
}

// File: contracts/interfaces/IMessageReceiverApp.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity >=0.8.0;

interface IMessageReceiverApp {
    enum ExecutionStatus {
        Fail, // execution failed, finalized
        Success, // execution succeeded, finalized
        Retry // execution rejected, can retry later
    }

    /**
     * @notice Called by MessageBus (MessageBusReceiver) if the process is originated from MessageBus (MessageBusSender)'s
     *         sendMessageWithTransfer it is only called when the tokens are checked to be arrived at this contract's address.
     * @param _sender The address of the source app contract
     * @param _token The address of the token that comes out of the bridge
     * @param _amount The amount of tokens received at this contract through the cross-chain bridge.
     *        the contract that implements this contract can safely assume that the tokens will arrive before this
     *        function is called.
     * @param _srcChainId The source chain ID where the transfer is originated from
     * @param _message Arbitrary message bytes originated from and encoded by the source app contract
     * @param _executor Address who called the MessageBus execution function
     */
    function executeMessageWithTransfer(
        address _sender,
        address _token,
        uint256 _amount,
        uint64 _srcChainId,
        bytes calldata _message,
        address _executor
    ) external payable returns (ExecutionStatus);

    /**
     * @notice Only called by MessageBus (MessageBusReceiver) if
     *         1. executeMessageWithTransfer reverts, or
     *         2. executeMessageWithTransfer returns ExecutionStatus.Fail
     * @param _sender The address of the source app contract
     * @param _token The address of the token that comes out of the bridge
     * @param _amount The amount of tokens received at this contract through the cross-chain bridge.
     *        the contract that implements this contract can safely assume that the tokens will arrive before this
     *        function is called.
     * @param _srcChainId The source chain ID where the transfer is originated from
     * @param _message Arbitrary message bytes originated from and encoded by the source app contract
     * @param _executor Address who called the MessageBus execution function
     */
    function executeMessageWithTransferFallback(
        address _sender,
        address _token,
        uint256 _amount,
        uint64 _srcChainId,
        bytes calldata _message,
        address _executor
    ) external payable returns (ExecutionStatus);

    /**
     * @notice Called by MessageBus (MessageBusReceiver) to process refund of the original transfer from this contract
     * @param _token The token address of the original transfer
     * @param _amount The amount of the original transfer
     * @param _message The same message associated with the original transfer
     * @param _executor Address who called the MessageBus execution function
     */
    function executeMessageWithTransferRefund(
        address _token,
        uint256 _amount,
        bytes calldata _message,
        address _executor
    ) external payable returns (ExecutionStatus);

    /**
     * @notice Called by MessageBus (MessageBusReceiver)
     * @param _sender The address of the source app contract
     * @param _srcChainId The source chain ID where the transfer is originated from
     * @param _message Arbitrary message bytes originated from and encoded by the source app contract
     * @param _executor Address who called the MessageBus execution function
     */
    function executeMessage(
        address _sender,
        uint64 _srcChainId,
        bytes calldata _message,
        address _executor
    ) external payable returns (ExecutionStatus);
}