ETH Price: $2,556.34 (+0.86%)

Transaction Decoder

Block:
22315826 at Apr-21-2025 07:16:59 AM +UTC
Transaction Fee:
0.000082072557075646 ETH $0.21
Gas Used:
254,249 Gas / 0.322803854 Gwei

Emitted Events:

299 FiatTokenProxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000c01db785ea6aa9740828c3c103e542dab38e8f40, 0x00000000000000000000000052e75d318cfb31f9a2edfa2dfee26b161255b233, 00000000000000000000000000000000000000000000000000000000012eb9ae )
300 OptimizedTransparentUpgradeableProxy.0xdf21c415b78ed2552cc9971249e32a053abce6087a0ae0fbf3f78db5174a3493( 0xdf21c415b78ed2552cc9971249e32a053abce6087a0ae0fbf3f78db5174a3493, 0000000000000000000000000000000000000000000000000001f4ed07ccef22 )
301 UltraLightNodeV2.RelayerParams( adapterParams=0x00010000000000000000000000000000000000000000000000000000000000030D40, outboundProofType=2 )
302 OptimizedTransparentUpgradeableProxy.0x4e41ee13e03cd5e0446487b524fdc48af6acf26c074dacdbdfb6b574b42c8146( 0x4e41ee13e03cd5e0446487b524fdc48af6acf26c074dacdbdfb6b574b42c8146, 0000000000000000000000000000000000000000000000000000000000000099, 0000000000000000000000000000000000000000000000000000000000000002, 000000000000000000000000000000000000000000000000000000000000000f, 00000000000000000000000052e75d318cfb31f9a2edfa2dfee26b161255b233, 0000000000000000000000000000000000000000000000000000013836e4268e )
303 UltraLightNodeV2.Packet( payload=0x0000000000001539006552E75D318CFB31F9A2EDFA2DFEE26B161255B2330099A4218E1F39DA4AADAC971066458DB56E901BCBDE0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000A0B86991C6218B36C1D19D4A2E9EB0CE3606EB48000000000000000000000000C01DB785EA6AA9740828C3C103E542DAB38E8F4000000000000000000000000000000000000000000000000000000000012EB9AE )
304 OriginalTokenBridge.SendToken( token=FiatTokenProxy, from=[Sender] 0xc01db785ea6aa9740828c3c103e542dab38e8f40, to=[Sender] 0xc01db785ea6aa9740828c3c103e542dab38e8f40, amount=19839406 )

Account State Difference:

  Address   Before After State Difference Code
(Titan Builder)
37.49033916280031262 Eth37.490339336811887706 Eth0.000000174011575086
0x4D73AdB7...401A178E2
(Layer Zero: Ultra Light Node v2)
1.671327777487530913 Eth1.671879892290257233 Eth0.00055211480272632
0x52e75D31...61255B233
0x5B905fE0...FAbf76068
(LayerZero: Nonce)
0x66A71Dce...C225Cd675
(LayerZero: Ethereum Endpoint)
0xA0b86991...E3606eB48
0xc01DB785...Ab38e8f40
0.001754022414142114 Eth
Nonce: 74
0.001119835054340148 Eth
Nonce: 75
0.000634187359801966

Execution Trace

ETH 0.00055211480272632 OriginalTokenBridge.bridge( token=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48, amountLD=19839406, to=0xc01DB785EA6Aa9740828c3C103e542dAb38e8f40, callParams=[{name:refundAddress, type:address, order:1, indexed:false, value:0xc01DB785EA6Aa9740828c3C103e542dAb38e8f40, valueString:0xc01DB785EA6Aa9740828c3C103e542dAb38e8f40}, {name:zroPaymentAddress, type:address, order:2, indexed:false, value:0x0000000000000000000000000000000000000000, valueString:0x0000000000000000000000000000000000000000}], adapterParams=0x )
  • FiatTokenProxy.70a08231( )
    • FiatTokenV2_2.balanceOf( account=0x52e75D318cFB31f9A2EdFa2DFee26B161255B233 ) => ( 757571744573 )
    • FiatTokenProxy.23b872dd( )
      • FiatTokenV2_2.transferFrom( from=0xc01DB785EA6Aa9740828c3C103e542dAb38e8f40, to=0x52e75D318cFB31f9A2EdFa2DFee26B161255B233, value=19839406 ) => ( True )
      • FiatTokenProxy.70a08231( )
        • FiatTokenV2_2.balanceOf( account=0x52e75D318cFB31f9A2EdFa2DFee26B161255B233 ) => ( 757591583979 )
        • ETH 0.00055211480272632 Endpoint.send( _dstChainId=153, _destination=0xA4218E1F39DA4AADAC971066458DB56E901BCBDE52E75D318CFB31F9A2EDFA2DFEE26B161255B233, _payload=0x0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000A0B86991C6218B36C1D19D4A2E9EB0CE3606EB48000000000000000000000000C01DB785EA6AA9740828C3C103E542DAB38E8F4000000000000000000000000000000000000000000000000000000000012EB9AE, _refundAddress=0xc01DB785EA6Aa9740828c3C103e542dAb38e8f40, _zroPaymentAddress=0x0000000000000000000000000000000000000000, _adapterParams=0x )
          • ETH 0.00055211480272632 UltraLightNodeV2.send( _ua=0x52e75D318cFB31f9A2EdFa2DFee26B161255B233, 5433, _dstChainId=153, _path=0xA4218E1F39DA4AADAC971066458DB56E901BCBDE52E75D318CFB31F9A2EDFA2DFEE26B161255B233, _payload=0x0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000A0B86991C6218B36C1D19D4A2E9EB0CE3606EB48000000000000000000000000C01DB785EA6AA9740828C3C103E542DAB38E8F4000000000000000000000000000000000000000000000000000000000012EB9AE, _refundAddress=0xc01DB785EA6Aa9740828c3C103e542dAb38e8f40, _zroPaymentAddress=0x0000000000000000000000000000000000000000, _adapterParams=0x )
            • NonceContract.increment( _chainId=153, _ua=0x52e75D318cFB31f9A2EdFa2DFee26B161255B233, _path=0xA4218E1F39DA4AADAC971066458DB56E901BCBDE52E75D318CFB31F9A2EDFA2DFEE26B161255B233 ) => ( 5433 )
              • Endpoint.getSendLibraryAddress( _userApplication=0x52e75D318cFB31f9A2EdFa2DFee26B161255B233 ) => ( sendLibraryAddress=0x4D73AdB72bC3DD368966edD0f0b2148401A178E2 )
              • OptimizedTransparentUpgradeableProxy.5886ea65( )
                • 0xb830a5afcbebb936c30c607a18bbba9f5b0a592f.5886ea65( )
                  • OptimizedTransparentUpgradeableProxy.88a4124c( )
                    • 0x319ae539b5ba554b09a46791cdb88b10e4d8f627.88a4124c( )
                    • OptimizedTransparentUpgradeableProxy.c5e193cd( )
                      • 0x3eea8d627ab6983fffc7027ee623fd7699343fc1.c5e193cd( )
                        • OptimizedTransparentUpgradeableProxy.7bc3c9ab( )
                          • 0x319ae539b5ba554b09a46791cdb88b10e4d8f627.7bc3c9ab( )
                          • TreasuryV2.getFees( payInZro=False, relayerFee=550773852008226, oracleFee=1340950718094 ) => ( 0 )
                            File 1 of 10: OriginalTokenBridge
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.17;
                            import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                            import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
                            import {LzLib} from "@layerzerolabs/solidity-examples/contracts/libraries/LzLib.sol";
                            import {TokenBridgeBase} from "./TokenBridgeBase.sol";
                            import {IWETH} from "./interfaces/IWETH.sol";
                            /// @dev Locks an ERC20 on the source chain and sends LZ message to the remote chain to mint a wrapped token
                            contract OriginalTokenBridge is TokenBridgeBase {
                                using SafeERC20 for IERC20;
                                /// @notice Tokens that can be bridged to the remote chain
                                mapping(address => bool) public supportedTokens;
                                /// @notice Token conversion rates from local decimals (LD) to shared decimals (SD).
                                /// E.g., if local decimals is 18 and shared decimals is 6, the conversion rate is 10^12
                                mapping(address => uint) public LDtoSDConversionRate;
                                /// @notice Total value locked per each supported token in shared decimals
                                mapping(address => uint) public totalValueLockedSD;
                                /// @notice LayerZero id of the remote chain where wrapped tokens are minted
                                uint16 public remoteChainId;
                                /// @notice Address of the wrapped native gas token (e.g. WETH, WBNB, WMATIC)
                                address public immutable weth;
                                event SendToken(address token, address from, address to, uint amount);
                                event ReceiveToken(address token, address to, uint amount);
                                event SetRemoteChainId(uint16 remoteChainId);
                                event RegisterToken(address token);
                                event WithdrawFee(address indexed token, address to, uint amount);
                                constructor(address _endpoint, uint16 _remoteChainId, address _weth) TokenBridgeBase(_endpoint) {
                                    require(_weth != address(0), "OriginalTokenBridge: invalid WETH address");
                                    remoteChainId = _remoteChainId;
                                    weth = _weth;
                                }
                                /// @notice Registers a token for bridging
                                /// @param token address of the token
                                /// @param sharedDecimals number of decimals used for all original tokens mapped to the same wrapped token.
                                /// E.g., 6 is shared decimals for USDC on Ethereum, BSC and Polygon
                                function registerToken(address token, uint8 sharedDecimals) external onlyOwner {
                                    require(token != address(0), "OriginalTokenBridge: invalid token address");
                                    require(!supportedTokens[token], "OriginalTokenBridge: token already registered");
                                    uint8 localDecimals = _getTokenDecimals(token);
                                    require(localDecimals >= sharedDecimals, "OriginalTokenBridge: shared decimals must be less than or equal to local decimals");
                                    supportedTokens[token] = true;
                                    LDtoSDConversionRate[token] = 10**(localDecimals - sharedDecimals);
                                    emit RegisterToken(token);
                                }
                                function setRemoteChainId(uint16 _remoteChainId) external onlyOwner {
                                    remoteChainId = _remoteChainId;
                                    emit SetRemoteChainId(_remoteChainId);
                                }
                                function accruedFeeLD(address token) public view returns (uint) {
                                    return IERC20(token).balanceOf(address(this)) - _amountSDtoLD(token, totalValueLockedSD[token]);
                                }
                                function estimateBridgeFee(bool useZro, bytes calldata adapterParams) public view returns (uint nativeFee, uint zroFee) {
                                    // Only the payload format matters when estimating fee, not the actual data
                                    bytes memory payload = abi.encode(PT_MINT, address(this), address(this), 0);
                                    return lzEndpoint.estimateFees(remoteChainId, address(this), payload, useZro, adapterParams);
                                }
                                /// @notice Bridges ERC20 to the remote chain
                                /// @dev Locks an ERC20 on the source chain and sends LZ message to the remote chain to mint a wrapped token
                                function bridge(address token, uint amountLD, address to, LzLib.CallParams calldata callParams, bytes memory adapterParams) external payable nonReentrant {
                                    require(supportedTokens[token], "OriginalTokenBridge: token is not supported");
                               
                                    // Supports tokens with transfer fee
                                    uint balanceBefore = IERC20(token).balanceOf(address(this));
                                    IERC20(token).safeTransferFrom(msg.sender, address(this), amountLD);
                                    uint balanceAfter = IERC20(token).balanceOf(address(this));
                                    (uint amountWithoutDustLD, uint dust) = _removeDust(token, balanceAfter - balanceBefore);
                                    // return dust to the sender
                                    if (dust > 0) {
                                        IERC20(token).safeTransfer(msg.sender, dust);
                                    }
                                    _bridge(token, amountWithoutDustLD, to, msg.value, callParams, adapterParams);
                                }
                                /// @notice Bridges ETH to the remote chain
                                /// @dev Locks WETH on the source chain and sends LZ message to the remote chain to mint a wrapped token
                                function bridgeETH(uint amountLD, address to, LzLib.CallParams calldata callParams, bytes memory adapterParams) external payable nonReentrant {
                                    require(supportedTokens[weth], "OriginalTokenBridge: token is not supported");
                                    require(msg.value >= amountLD, "OriginalTokenBridge: not enough value sent");
                                    (uint amountWithoutDustLD, ) = _removeDust(weth, amountLD);
                                    IWETH(weth).deposit{value: amountWithoutDustLD}();
                                    _bridge(weth, amountWithoutDustLD, to, msg.value - amountWithoutDustLD, callParams, adapterParams);
                                }
                                function _bridge(address token, uint amountLD, address to, uint nativeFee, LzLib.CallParams calldata callParams, bytes memory adapterParams) private {
                                    require(to != address(0), "OriginalTokenBridge: invalid to");
                                    _checkAdapterParams(remoteChainId, PT_MINT, adapterParams);
                                    uint amountSD = _amountLDtoSD(token, amountLD);
                                    require(amountSD > 0, "OriginalTokenBridge: invalid amount");
                                    totalValueLockedSD[token] += amountSD;
                                    bytes memory payload = abi.encode(PT_MINT, token, to, amountSD);
                                    _lzSend(remoteChainId, payload, callParams.refundAddress, callParams.zroPaymentAddress, adapterParams, nativeFee);
                                    emit SendToken(token, msg.sender, to, amountLD);
                                }
                                function withdrawFee(address token, address to, uint amountLD) public onlyOwner {
                                    uint feeLD = accruedFeeLD(token);
                                    require(amountLD <= feeLD, "OriginalTokenBridge: not enough fees collected");
                                    IERC20(token).safeTransfer(to, amountLD);
                                    emit WithdrawFee(token, to, amountLD);
                                }
                                /// @notice Receives ERC20 tokens or ETH from the remote chain
                                /// @dev Unlocks locked ERC20 tokens or ETH in response to LZ message from the remote chain
                                function _nonblockingLzReceive(uint16 srcChainId, bytes memory, uint64, bytes memory payload) internal virtual override {
                                    require(srcChainId == remoteChainId, "OriginalTokenBridge: invalid source chain id");
                                    (uint8 packetType, address token, address to, uint withdrawalAmountSD, uint totalAmountSD, bool unwrapWeth) = abi.decode(payload, (uint8, address, address, uint, uint, bool));
                                    require(packetType == PT_UNLOCK, "OriginalTokenBridge: unknown packet type");
                                    require(supportedTokens[token], "OriginalTokenBridge: token is not supported");
                                    totalValueLockedSD[token] -= totalAmountSD;
                                    uint withdrawalAmountLD = _amountSDtoLD(token, withdrawalAmountSD);
                                    if (token == weth && unwrapWeth) {
                                        IWETH(weth).withdraw(withdrawalAmountLD);
                                        (bool success, ) = payable(to).call{value: withdrawalAmountLD}("");
                                        require(success, "OriginalTokenBridge: failed to send");
                                        emit ReceiveToken(address(0), to, withdrawalAmountLD);
                                    } else {
                                        IERC20(token).safeTransfer(to, withdrawalAmountLD);
                                        emit ReceiveToken(token, to, withdrawalAmountLD);
                                    }
                                }
                                function _getTokenDecimals(address token) internal view returns (uint8) {
                                    (bool success, bytes memory data) = token.staticcall(abi.encodeWithSignature("decimals()"));
                                    require(success, "OriginalTokenBridge: failed to get token decimals");
                                    return abi.decode(data, (uint8));
                                }
                                function _amountSDtoLD(address token, uint amountSD) internal view returns (uint) {
                                    return amountSD * LDtoSDConversionRate[token];
                                }
                                function _amountLDtoSD(address token, uint amountLD) internal view returns (uint) {
                                    return amountLD / LDtoSDConversionRate[token];
                                }
                                function _removeDust(address token, uint amountLD) internal view returns (uint amountWithoutDustLD, uint dust) {
                                    dust = amountLD % LDtoSDConversionRate[token];
                                    amountWithoutDustLD = amountLD - dust;
                                }
                                /// @dev Allows receiving ETH when calling WETH.withdraw()
                                receive() external payable {}
                            }// 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;
                                }
                            }
                            // 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);
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.5.0;
                            interface ILayerZeroReceiver {
                                // @notice LayerZero endpoint will invoke this function to deliver the message on the destination
                                // @param _srcChainId - the source endpoint identifier
                                // @param _srcAddress - the source sending contract address from the source chain
                                // @param _nonce - the ordered message nonce
                                // @param _payload - the signed payload is the UA bytes has encoded to be sent
                                function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.5.0;
                            interface ILayerZeroUserApplicationConfig {
                                // @notice set the configuration of the LayerZero messaging library of the specified version
                                // @param _version - messaging library version
                                // @param _chainId - the chainId for the pending config change
                                // @param _configType - type of configuration. every messaging library has its own convention.
                                // @param _config - configuration in the bytes. can encode arbitrary content.
                                function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
                                // @notice set the send() LayerZero messaging library version to _version
                                // @param _version - new messaging library version
                                function setSendVersion(uint16 _version) external;
                                // @notice set the lzReceive() LayerZero messaging library version to _version
                                // @param _version - new messaging library version
                                function setReceiveVersion(uint16 _version) external;
                                // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
                                // @param _srcChainId - the chainId of the source chain
                                // @param _srcAddress - the contract address of the source contract at the source chain
                                function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.5.0;
                            import "./ILayerZeroUserApplicationConfig.sol";
                            interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
                                // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
                                // @param _dstChainId - the destination chain identifier
                                // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
                                // @param _payload - a custom bytes payload to send to the destination contract
                                // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
                                // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
                                // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
                                function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                                // @notice used by the messaging library to publish verified payload
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source contract (as bytes) at the source chain
                                // @param _dstAddress - the address on destination chain
                                // @param _nonce - the unbound message ordering nonce
                                // @param _gasLimit - the gas limit for external contract execution
                                // @param _payload - verified payload to send to the destination contract
                                function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
                                // @notice get the inboundNonce of a lzApp from a source chain which could be EVM or non-EVM chain
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
                                // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
                                // @param _srcAddress - the source chain contract address
                                function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
                                // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
                                // @param _dstChainId - the destination chain identifier
                                // @param _userApplication - the user app address on this EVM chain
                                // @param _payload - the custom message to send over LayerZero
                                // @param _payInZRO - if false, user app pays the protocol fee in native token
                                // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
                                function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                                // @notice get this Endpoint's immutable source identifier
                                function getChainId() external view returns (uint16);
                                // @notice the interface to retry failed message on this Endpoint destination
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                // @param _payload - the payload to be retried
                                function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
                                // @notice query if any STORED payload (message blocking) at the endpoint.
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
                                // @notice query if the _libraryAddress is valid for sending msgs.
                                // @param _userApplication - the user app address on this EVM chain
                                function getSendLibraryAddress(address _userApplication) external view returns (address);
                                // @notice query if the _libraryAddress is valid for receiving msgs.
                                // @param _userApplication - the user app address on this EVM chain
                                function getReceiveLibraryAddress(address _userApplication) external view returns (address);
                                // @notice query if the non-reentrancy guard for send() is on
                                // @return true if the guard is on. false otherwise
                                function isSendingPayload() external view returns (bool);
                                // @notice query if the non-reentrancy guard for receive() is on
                                // @return true if the guard is on. false otherwise
                                function isReceivingPayload() external view returns (bool);
                                // @notice get the configuration of the LayerZero messaging library of the specified version
                                // @param _version - messaging library version
                                // @param _chainId - the chainId for the pending config change
                                // @param _userApplication - the contract address of the user application
                                // @param _configType - type of configuration. every messaging library has its own convention.
                                function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                                // @notice get the send() LayerZero messaging library version
                                // @param _userApplication - the contract address of the user application
                                function getSendVersion(address _userApplication) external view returns (uint16);
                                // @notice get the lzReceive() LayerZero messaging library version
                                // @param _userApplication - the contract address of the user application
                                function getReceiveVersion(address _userApplication) external view returns (uint16);
                            }
                            // SPDX-License-Identifier: Unlicense
                            /*
                             * @title Solidity Bytes Arrays Utils
                             * @author Gonçalo Sá <[email protected]>
                             *
                             * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
                             *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
                             */
                            pragma solidity >=0.8.0 <0.9.0;
                            library BytesLib {
                                function concat(
                                    bytes memory _preBytes,
                                    bytes memory _postBytes
                                )
                                internal
                                pure
                                returns (bytes memory)
                                {
                                    bytes memory tempBytes;
                                    assembly {
                                    // Get a location of some free memory and store it in tempBytes as
                                    // Solidity does for memory variables.
                                        tempBytes := mload(0x40)
                                    // Store the length of the first bytes array at the beginning of
                                    // the memory for tempBytes.
                                        let length := mload(_preBytes)
                                        mstore(tempBytes, length)
                                    // Maintain a memory counter for the current write location in the
                                    // temp bytes array by adding the 32 bytes for the array length to
                                    // the starting location.
                                        let mc := add(tempBytes, 0x20)
                                    // Stop copying when the memory counter reaches the length of the
                                    // first bytes array.
                                        let end := add(mc, length)
                                        for {
                                        // Initialize a copy counter to the start of the _preBytes data,
                                        // 32 bytes into its memory.
                                            let cc := add(_preBytes, 0x20)
                                        } lt(mc, end) {
                                        // Increase both counters by 32 bytes each iteration.
                                            mc := add(mc, 0x20)
                                            cc := add(cc, 0x20)
                                        } {
                                        // Write the _preBytes data into the tempBytes memory 32 bytes
                                        // at a time.
                                            mstore(mc, mload(cc))
                                        }
                                    // Add the length of _postBytes to the current length of tempBytes
                                    // and store it as the new length in the first 32 bytes of the
                                    // tempBytes memory.
                                        length := mload(_postBytes)
                                        mstore(tempBytes, add(length, mload(tempBytes)))
                                    // Move the memory counter back from a multiple of 0x20 to the
                                    // actual end of the _preBytes data.
                                        mc := end
                                    // Stop copying when the memory counter reaches the new combined
                                    // length of the arrays.
                                        end := add(mc, length)
                                        for {
                                            let cc := add(_postBytes, 0x20)
                                        } lt(mc, end) {
                                            mc := add(mc, 0x20)
                                            cc := add(cc, 0x20)
                                        } {
                                            mstore(mc, mload(cc))
                                        }
                                    // Update the free-memory pointer by padding our last write location
                                    // to 32 bytes: add 31 bytes to the end of tempBytes to move to the
                                    // next 32 byte block, then round down to the nearest multiple of
                                    // 32. If the sum of the length of the two arrays is zero then add
                                    // one before rounding down to leave a blank 32 bytes (the length block with 0).
                                        mstore(0x40, and(
                                        add(add(end, iszero(add(length, mload(_preBytes)))), 31),
                                        not(31) // Round down to the nearest 32 bytes.
                                        ))
                                    }
                                    return tempBytes;
                                }
                                function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
                                    assembly {
                                    // Read the first 32 bytes of _preBytes storage, which is the length
                                    // of the array. (We don't need to use the offset into the slot
                                    // because arrays use the entire slot.)
                                        let fslot := sload(_preBytes.slot)
                                    // Arrays of 31 bytes or less have an even value in their slot,
                                    // while longer arrays have an odd value. The actual length is
                                    // the slot divided by two for odd values, and the lowest order
                                    // byte divided by two for even values.
                                    // If the slot is even, bitwise and the slot with 255 and divide by
                                    // two to get the length. If the slot is odd, bitwise and the slot
                                    // with -1 and divide by two.
                                        let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
                                        let mlength := mload(_postBytes)
                                        let newlength := add(slength, mlength)
                                    // slength can contain both the length and contents of the array
                                    // if length < 32 bytes so let's prepare for that
                                    // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                                        switch add(lt(slength, 32), lt(newlength, 32))
                                        case 2 {
                                        // Since the new array still fits in the slot, we just need to
                                        // update the contents of the slot.
                                        // uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
                                            sstore(
                                            _preBytes.slot,
                                            // all the modifications to the slot are inside this
                                            // next block
                                            add(
                                            // we can just add to the slot contents because the
                                            // bytes we want to change are the LSBs
                                            fslot,
                                            add(
                                            mul(
                                            div(
                                            // load the bytes from memory
                                            mload(add(_postBytes, 0x20)),
                                            // zero all bytes to the right
                                            exp(0x100, sub(32, mlength))
                                            ),
                                            // and now shift left the number of bytes to
                                            // leave space for the length in the slot
                                            exp(0x100, sub(32, newlength))
                                            ),
                                            // increase length by the double of the memory
                                            // bytes length
                                            mul(mlength, 2)
                                            )
                                            )
                                            )
                                        }
                                        case 1 {
                                        // The stored value fits in the slot, but the combined value
                                        // will exceed it.
                                        // get the keccak hash to get the contents of the array
                                            mstore(0x0, _preBytes.slot)
                                            let sc := add(keccak256(0x0, 0x20), div(slength, 32))
                                        // save new length
                                            sstore(_preBytes.slot, add(mul(newlength, 2), 1))
                                        // The contents of the _postBytes array start 32 bytes into
                                        // the structure. Our first read should obtain the `submod`
                                        // bytes that can fit into the unused space in the last word
                                        // of the stored array. To get this, we read 32 bytes starting
                                        // from `submod`, so the data we read overlaps with the array
                                        // contents by `submod` bytes. Masking the lowest-order
                                        // `submod` bytes allows us to add that value directly to the
                                        // stored value.
                                            let submod := sub(32, slength)
                                            let mc := add(_postBytes, submod)
                                            let end := add(_postBytes, mlength)
                                            let mask := sub(exp(0x100, submod), 1)
                                            sstore(
                                            sc,
                                            add(
                                            and(
                                            fslot,
                                            0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00
                                            ),
                                            and(mload(mc), mask)
                                            )
                                            )
                                            for {
                                                mc := add(mc, 0x20)
                                                sc := add(sc, 1)
                                            } lt(mc, end) {
                                                sc := add(sc, 1)
                                                mc := add(mc, 0x20)
                                            } {
                                                sstore(sc, mload(mc))
                                            }
                                            mask := exp(0x100, sub(mc, end))
                                            sstore(sc, mul(div(mload(mc), mask), mask))
                                        }
                                        default {
                                        // get the keccak hash to get the contents of the array
                                            mstore(0x0, _preBytes.slot)
                                        // Start copying to the last used word of the stored array.
                                            let sc := add(keccak256(0x0, 0x20), div(slength, 32))
                                        // save new length
                                            sstore(_preBytes.slot, add(mul(newlength, 2), 1))
                                        // Copy over the first `submod` bytes of the new data as in
                                        // case 1 above.
                                            let slengthmod := mod(slength, 32)
                                            let mlengthmod := mod(mlength, 32)
                                            let submod := sub(32, slengthmod)
                                            let mc := add(_postBytes, submod)
                                            let end := add(_postBytes, mlength)
                                            let mask := sub(exp(0x100, submod), 1)
                                            sstore(sc, add(sload(sc), and(mload(mc), mask)))
                                            for {
                                                sc := add(sc, 1)
                                                mc := add(mc, 0x20)
                                            } lt(mc, end) {
                                                sc := add(sc, 1)
                                                mc := add(mc, 0x20)
                                            } {
                                                sstore(sc, mload(mc))
                                            }
                                            mask := exp(0x100, sub(mc, end))
                                            sstore(sc, mul(div(mload(mc), mask), mask))
                                        }
                                    }
                                }
                                function slice(
                                    bytes memory _bytes,
                                    uint256 _start,
                                    uint256 _length
                                )
                                internal
                                pure
                                returns (bytes memory)
                                {
                                    require(_length + 31 >= _length, "slice_overflow");
                                    require(_bytes.length >= _start + _length, "slice_outOfBounds");
                                    bytes memory tempBytes;
                                    assembly {
                                        switch iszero(_length)
                                        case 0 {
                                        // Get a location of some free memory and store it in tempBytes as
                                        // Solidity does for memory variables.
                                            tempBytes := mload(0x40)
                                        // The first word of the slice result is potentially a partial
                                        // word read from the original array. To read it, we calculate
                                        // the length of that partial word and start copying that many
                                        // bytes into the array. The first word we copy will start with
                                        // data we don't care about, but the last `lengthmod` bytes will
                                        // land at the beginning of the contents of the new array. When
                                        // we're done copying, we overwrite the full first word with
                                        // the actual length of the slice.
                                            let lengthmod := and(_length, 31)
                                        // The multiplication in the next line is necessary
                                        // because when slicing multiples of 32 bytes (lengthmod == 0)
                                        // the following copy loop was copying the origin's length
                                        // and then ending prematurely not copying everything it should.
                                            let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                                            let end := add(mc, _length)
                                            for {
                                            // The multiplication in the next line has the same exact purpose
                                            // as the one above.
                                                let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                                            } lt(mc, end) {
                                                mc := add(mc, 0x20)
                                                cc := add(cc, 0x20)
                                            } {
                                                mstore(mc, mload(cc))
                                            }
                                            mstore(tempBytes, _length)
                                        //update free-memory pointer
                                        //allocating the array padded to 32 bytes like the compiler does now
                                            mstore(0x40, and(add(mc, 31), not(31)))
                                        }
                                        //if we want a zero-length slice let's just return a zero-length array
                                        default {
                                            tempBytes := mload(0x40)
                                        //zero out the 32 bytes slice we are about to return
                                        //we need to do it because Solidity does not garbage collect
                                            mstore(tempBytes, 0)
                                            mstore(0x40, add(tempBytes, 0x20))
                                        }
                                    }
                                    return tempBytes;
                                }
                                function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
                                    require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
                                    address tempAddress;
                                    assembly {
                                        tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
                                    }
                                    return tempAddress;
                                }
                                function toUint8(bytes memory _bytes, uint256 _start) internal pure returns (uint8) {
                                    require(_bytes.length >= _start + 1 , "toUint8_outOfBounds");
                                    uint8 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0x1), _start))
                                    }
                                    return tempUint;
                                }
                                function toUint16(bytes memory _bytes, uint256 _start) internal pure returns (uint16) {
                                    require(_bytes.length >= _start + 2, "toUint16_outOfBounds");
                                    uint16 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0x2), _start))
                                    }
                                    return tempUint;
                                }
                                function toUint32(bytes memory _bytes, uint256 _start) internal pure returns (uint32) {
                                    require(_bytes.length >= _start + 4, "toUint32_outOfBounds");
                                    uint32 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0x4), _start))
                                    }
                                    return tempUint;
                                }
                                function toUint64(bytes memory _bytes, uint256 _start) internal pure returns (uint64) {
                                    require(_bytes.length >= _start + 8, "toUint64_outOfBounds");
                                    uint64 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0x8), _start))
                                    }
                                    return tempUint;
                                }
                                function toUint96(bytes memory _bytes, uint256 _start) internal pure returns (uint96) {
                                    require(_bytes.length >= _start + 12, "toUint96_outOfBounds");
                                    uint96 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0xc), _start))
                                    }
                                    return tempUint;
                                }
                                function toUint128(bytes memory _bytes, uint256 _start) internal pure returns (uint128) {
                                    require(_bytes.length >= _start + 16, "toUint128_outOfBounds");
                                    uint128 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0x10), _start))
                                    }
                                    return tempUint;
                                }
                                function toUint256(bytes memory _bytes, uint256 _start) internal pure returns (uint256) {
                                    require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
                                    uint256 tempUint;
                                    assembly {
                                        tempUint := mload(add(add(_bytes, 0x20), _start))
                                    }
                                    return tempUint;
                                }
                                function toBytes32(bytes memory _bytes, uint256 _start) internal pure returns (bytes32) {
                                    require(_bytes.length >= _start + 32, "toBytes32_outOfBounds");
                                    bytes32 tempBytes32;
                                    assembly {
                                        tempBytes32 := mload(add(add(_bytes, 0x20), _start))
                                    }
                                    return tempBytes32;
                                }
                                function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
                                    bool success = true;
                                    assembly {
                                        let length := mload(_preBytes)
                                    // if lengths don't match the arrays are not equal
                                        switch eq(length, mload(_postBytes))
                                        case 1 {
                                        // cb is a circuit breaker in the for loop since there's
                                        //  no said feature for inline assembly loops
                                        // cb = 1 - don't breaker
                                        // cb = 0 - break
                                            let cb := 1
                                            let mc := add(_preBytes, 0x20)
                                            let end := add(mc, length)
                                            for {
                                                let cc := add(_postBytes, 0x20)
                                            // the next line is the loop condition:
                                            // while(uint256(mc < end) + cb == 2)
                                            } eq(add(lt(mc, end), cb), 2) {
                                                mc := add(mc, 0x20)
                                                cc := add(cc, 0x20)
                                            } {
                                            // if any of these checks fails then arrays are not equal
                                                if iszero(eq(mload(mc), mload(cc))) {
                                                // unsuccess:
                                                    success := 0
                                                    cb := 0
                                                }
                                            }
                                        }
                                        default {
                                        // unsuccess:
                                            success := 0
                                        }
                                    }
                                    return success;
                                }
                                function equalStorage(
                                    bytes storage _preBytes,
                                    bytes memory _postBytes
                                )
                                internal
                                view
                                returns (bool)
                                {
                                    bool success = true;
                                    assembly {
                                    // we know _preBytes_offset is 0
                                        let fslot := sload(_preBytes.slot)
                                    // Decode the length of the stored array like in concatStorage().
                                        let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
                                        let mlength := mload(_postBytes)
                                    // if lengths don't match the arrays are not equal
                                        switch eq(slength, mlength)
                                        case 1 {
                                        // slength can contain both the length and contents of the array
                                        // if length < 32 bytes so let's prepare for that
                                        // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                                            if iszero(iszero(slength)) {
                                                switch lt(slength, 32)
                                                case 1 {
                                                // blank the last byte which is the length
                                                    fslot := mul(div(fslot, 0x100), 0x100)
                                                    if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
                                                    // unsuccess:
                                                        success := 0
                                                    }
                                                }
                                                default {
                                                // cb is a circuit breaker in the for loop since there's
                                                //  no said feature for inline assembly loops
                                                // cb = 1 - don't breaker
                                                // cb = 0 - break
                                                    let cb := 1
                                                // get the keccak hash to get the contents of the array
                                                    mstore(0x0, _preBytes.slot)
                                                    let sc := keccak256(0x0, 0x20)
                                                    let mc := add(_postBytes, 0x20)
                                                    let end := add(mc, mlength)
                                                // the next line is the loop condition:
                                                // while(uint256(mc < end) + cb == 2)
                                                    for {} eq(add(lt(mc, end), cb), 2) {
                                                        sc := add(sc, 1)
                                                        mc := add(mc, 0x20)
                                                    } {
                                                        if iszero(eq(sload(sc), mload(mc))) {
                                                        // unsuccess:
                                                            success := 0
                                                            cb := 0
                                                        }
                                                    }
                                                }
                                            }
                                        }
                                        default {
                                        // unsuccess:
                                            success := 0
                                        }
                                    }
                                    return success;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "@openzeppelin/contracts/access/Ownable.sol";
                            import "../interfaces/ILayerZeroReceiver.sol";
                            import "../interfaces/ILayerZeroUserApplicationConfig.sol";
                            import "../interfaces/ILayerZeroEndpoint.sol";
                            import "../util/BytesLib.sol";
                            /*
                             * a generic LzReceiver implementation
                             */
                            abstract contract LzApp is Ownable, ILayerZeroReceiver, ILayerZeroUserApplicationConfig {
                                using BytesLib for bytes;
                                ILayerZeroEndpoint public immutable lzEndpoint;
                                mapping(uint16 => bytes) public trustedRemoteLookup;
                                mapping(uint16 => mapping(uint16 => uint)) public minDstGasLookup;
                                address public precrime;
                                event SetPrecrime(address precrime);
                                event SetTrustedRemote(uint16 _remoteChainId, bytes _path);
                                event SetTrustedRemoteAddress(uint16 _remoteChainId, bytes _remoteAddress);
                                event SetMinDstGas(uint16 _dstChainId, uint16 _type, uint _minDstGas);
                                constructor(address _endpoint) {
                                    lzEndpoint = ILayerZeroEndpoint(_endpoint);
                                }
                                function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public virtual override {
                                    // lzReceive must be called by the endpoint for security
                                    require(_msgSender() == address(lzEndpoint), "LzApp: invalid endpoint caller");
                                    bytes memory trustedRemote = trustedRemoteLookup[_srcChainId];
                                    // if will still block the message pathway from (srcChainId, srcAddress). should not receive message from untrusted remote.
                                    require(_srcAddress.length == trustedRemote.length && trustedRemote.length > 0 && keccak256(_srcAddress) == keccak256(trustedRemote), "LzApp: invalid source sending contract");
                                    _blockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
                                }
                                // abstract function - the default behaviour of LayerZero is blocking. See: NonblockingLzApp if you dont need to enforce ordered messaging
                                function _blockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual;
                                function _lzSend(uint16 _dstChainId, bytes memory _payload, address payable _refundAddress, address _zroPaymentAddress, bytes memory _adapterParams, uint _nativeFee) internal virtual {
                                    bytes memory trustedRemote = trustedRemoteLookup[_dstChainId];
                                    require(trustedRemote.length != 0, "LzApp: destination chain is not a trusted source");
                                    lzEndpoint.send{value: _nativeFee}(_dstChainId, trustedRemote, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
                                }
                                function _checkGasLimit(uint16 _dstChainId, uint16 _type, bytes memory _adapterParams, uint _extraGas) internal view virtual {
                                    uint providedGasLimit = _getGasLimit(_adapterParams);
                                    uint minGasLimit = minDstGasLookup[_dstChainId][_type] + _extraGas;
                                    require(minGasLimit > 0, "LzApp: minGasLimit not set");
                                    require(providedGasLimit >= minGasLimit, "LzApp: gas limit is too low");
                                }
                                function _getGasLimit(bytes memory _adapterParams) internal pure virtual returns (uint gasLimit) {
                                    require(_adapterParams.length >= 34, "LzApp: invalid adapterParams");
                                    assembly {
                                        gasLimit := mload(add(_adapterParams, 34))
                                    }
                                }
                                //---------------------------UserApplication config----------------------------------------
                                function getConfig(uint16 _version, uint16 _chainId, address, uint _configType) external view returns (bytes memory) {
                                    return lzEndpoint.getConfig(_version, _chainId, address(this), _configType);
                                }
                                // generic config for LayerZero user Application
                                function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external override onlyOwner {
                                    lzEndpoint.setConfig(_version, _chainId, _configType, _config);
                                }
                                function setSendVersion(uint16 _version) external override onlyOwner {
                                    lzEndpoint.setSendVersion(_version);
                                }
                                function setReceiveVersion(uint16 _version) external override onlyOwner {
                                    lzEndpoint.setReceiveVersion(_version);
                                }
                                function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override onlyOwner {
                                    lzEndpoint.forceResumeReceive(_srcChainId, _srcAddress);
                                }
                                // _path = abi.encodePacked(remoteAddress, localAddress)
                                // this function set the trusted path for the cross-chain communication
                                function setTrustedRemote(uint16 _srcChainId, bytes calldata _path) external onlyOwner {
                                    trustedRemoteLookup[_srcChainId] = _path;
                                    emit SetTrustedRemote(_srcChainId, _path);
                                }
                                function setTrustedRemoteAddress(uint16 _remoteChainId, bytes calldata _remoteAddress) external onlyOwner {
                                    trustedRemoteLookup[_remoteChainId] = abi.encodePacked(_remoteAddress, address(this));
                                    emit SetTrustedRemoteAddress(_remoteChainId, _remoteAddress);
                                }
                                function getTrustedRemoteAddress(uint16 _remoteChainId) external view returns (bytes memory) {
                                    bytes memory path = trustedRemoteLookup[_remoteChainId];
                                    require(path.length != 0, "LzApp: no trusted path record");
                                    return path.slice(0, path.length - 20); // the last 20 bytes should be address(this)
                                }
                                function setPrecrime(address _precrime) external onlyOwner {
                                    precrime = _precrime;
                                    emit SetPrecrime(_precrime);
                                }
                                function setMinDstGas(uint16 _dstChainId, uint16 _packetType, uint _minGas) external onlyOwner {
                                    require(_minGas > 0, "LzApp: invalid minGas");
                                    minDstGasLookup[_dstChainId][_packetType] = _minGas;
                                    emit SetMinDstGas(_dstChainId, _packetType, _minGas);
                                }
                                //--------------------------- VIEW FUNCTION ----------------------------------------
                                function isTrustedRemote(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool) {
                                    bytes memory trustedSource = trustedRemoteLookup[_srcChainId];
                                    return keccak256(trustedSource) == keccak256(_srcAddress);
                                }
                            }
                            // SPDX-License-Identifier: MIT OR Apache-2.0
                            pragma solidity >=0.7.6;
                            library ExcessivelySafeCall {
                                uint256 constant LOW_28_MASK =
                                0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
                                /// @notice Use when you _really_ really _really_ don't trust the called
                                /// contract. This prevents the called contract from causing reversion of
                                /// the caller in as many ways as we can.
                                /// @dev The main difference between this and a solidity low-level call is
                                /// that we limit the number of bytes that the callee can cause to be
                                /// copied to caller memory. This prevents stupid things like malicious
                                /// contracts returning 10,000,000 bytes causing a local OOG when copying
                                /// to memory.
                                /// @param _target The address to call
                                /// @param _gas The amount of gas to forward to the remote contract
                                /// @param _maxCopy The maximum number of bytes of returndata to copy
                                /// to memory.
                                /// @param _calldata The data to send to the remote contract
                                /// @return success and returndata, as `.call()`. Returndata is capped to
                                /// `_maxCopy` bytes.
                                function excessivelySafeCall(
                                    address _target,
                                    uint256 _gas,
                                    uint16 _maxCopy,
                                    bytes memory _calldata
                                ) internal returns (bool, bytes memory) {
                                    // set up for assembly call
                                    uint256 _toCopy;
                                    bool _success;
                                    bytes memory _returnData = new bytes(_maxCopy);
                                    // dispatch message to recipient
                                    // by assembly calling "handle" function
                                    // we call via assembly to avoid memcopying a very large returndata
                                    // returned by a malicious contract
                                    assembly {
                                        _success := call(
                                        _gas, // gas
                                        _target, // recipient
                                        0, // ether value
                                        add(_calldata, 0x20), // inloc
                                        mload(_calldata), // inlen
                                        0, // outloc
                                        0 // outlen
                                        )
                                    // limit our copy to 256 bytes
                                        _toCopy := returndatasize()
                                        if gt(_toCopy, _maxCopy) {
                                            _toCopy := _maxCopy
                                        }
                                    // Store the length of the copied bytes
                                        mstore(_returnData, _toCopy)
                                    // copy the bytes from returndata[0:_toCopy]
                                        returndatacopy(add(_returnData, 0x20), 0, _toCopy)
                                    }
                                    return (_success, _returnData);
                                }
                                /// @notice Use when you _really_ really _really_ don't trust the called
                                /// contract. This prevents the called contract from causing reversion of
                                /// the caller in as many ways as we can.
                                /// @dev The main difference between this and a solidity low-level call is
                                /// that we limit the number of bytes that the callee can cause to be
                                /// copied to caller memory. This prevents stupid things like malicious
                                /// contracts returning 10,000,000 bytes causing a local OOG when copying
                                /// to memory.
                                /// @param _target The address to call
                                /// @param _gas The amount of gas to forward to the remote contract
                                /// @param _maxCopy The maximum number of bytes of returndata to copy
                                /// to memory.
                                /// @param _calldata The data to send to the remote contract
                                /// @return success and returndata, as `.call()`. Returndata is capped to
                                /// `_maxCopy` bytes.
                                function excessivelySafeStaticCall(
                                    address _target,
                                    uint256 _gas,
                                    uint16 _maxCopy,
                                    bytes memory _calldata
                                ) internal view returns (bool, bytes memory) {
                                    // set up for assembly call
                                    uint256 _toCopy;
                                    bool _success;
                                    bytes memory _returnData = new bytes(_maxCopy);
                                    // dispatch message to recipient
                                    // by assembly calling "handle" function
                                    // we call via assembly to avoid memcopying a very large returndata
                                    // returned by a malicious contract
                                    assembly {
                                        _success := staticcall(
                                        _gas, // gas
                                        _target, // recipient
                                        add(_calldata, 0x20), // inloc
                                        mload(_calldata), // inlen
                                        0, // outloc
                                        0 // outlen
                                        )
                                    // limit our copy to 256 bytes
                                        _toCopy := returndatasize()
                                        if gt(_toCopy, _maxCopy) {
                                            _toCopy := _maxCopy
                                        }
                                    // Store the length of the copied bytes
                                        mstore(_returnData, _toCopy)
                                    // copy the bytes from returndata[0:_toCopy]
                                        returndatacopy(add(_returnData, 0x20), 0, _toCopy)
                                    }
                                    return (_success, _returnData);
                                }
                                /**
                                 * @notice Swaps function selectors in encoded contract calls
                                 * @dev Allows reuse of encoded calldata for functions with identical
                                 * argument types but different names. It simply swaps out the first 4 bytes
                                 * for the new selector. This function modifies memory in place, and should
                                 * only be used with caution.
                                 * @param _newSelector The new 4-byte selector
                                 * @param _buf The encoded contract args
                                 */
                                function swapSelector(bytes4 _newSelector, bytes memory _buf)
                                internal
                                pure
                                {
                                    require(_buf.length >= 4);
                                    uint256 _mask = LOW_28_MASK;
                                    assembly {
                                    // load the first word of
                                        let _word := mload(add(_buf, 0x20))
                                    // mask out the top 4 bytes
                                    // /x
                                        _word := and(_word, _mask)
                                        _word := or(_newSelector, _word)
                                        mstore(add(_buf, 0x20), _word)
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (security/ReentrancyGuard.sol)
                            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 making it call a
                                 * `private` function that does the actual work.
                                 */
                                modifier nonReentrant() {
                                    _nonReentrantBefore();
                                    _;
                                    _nonReentrantAfter();
                                }
                                function _nonReentrantBefore() private {
                                    // On the first call to nonReentrant, _status will be _NOT_ENTERED
                                    require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                                    // Any calls to nonReentrant after this point will fail
                                    _status = _ENTERED;
                                }
                                function _nonReentrantAfter() private {
                                    // By storing the original value once again, a refund is triggered (see
                                    // https://eips.ethereum.org/EIPS/eip-2200)
                                    _status = _NOT_ENTERED;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.0;
                            import "./LzApp.sol";
                            import "../util/ExcessivelySafeCall.sol";
                            /*
                             * the default LayerZero messaging behaviour is blocking, i.e. any failed message will block the channel
                             * this abstract class try-catch all fail messages and store locally for future retry. hence, non-blocking
                             * NOTE: if the srcAddress is not configured properly, it will still block the message pathway from (srcChainId, srcAddress)
                             */
                            abstract contract NonblockingLzApp is LzApp {
                                using ExcessivelySafeCall for address;
                                constructor(address _endpoint) LzApp(_endpoint) {}
                                mapping(uint16 => mapping(bytes => mapping(uint64 => bytes32))) public failedMessages;
                                event MessageFailed(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes _payload, bytes _reason);
                                event RetryMessageSuccess(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _payloadHash);
                                // overriding the virtual function in LzReceiver
                                function _blockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual override {
                                    (bool success, bytes memory reason) = address(this).excessivelySafeCall(gasleft(), 150, abi.encodeWithSelector(this.nonblockingLzReceive.selector, _srcChainId, _srcAddress, _nonce, _payload));
                                    // try-catch all errors/exceptions
                                    if (!success) {
                                        _storeFailedMessage(_srcChainId, _srcAddress, _nonce, _payload, reason);
                                    }
                                }
                                function _storeFailedMessage(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload, bytes memory _reason) internal virtual {
                                    failedMessages[_srcChainId][_srcAddress][_nonce] = keccak256(_payload);
                                    emit MessageFailed(_srcChainId, _srcAddress, _nonce, _payload, _reason);
                                }
                                function nonblockingLzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public virtual {
                                    // only internal transaction
                                    require(_msgSender() == address(this), "NonblockingLzApp: caller must be LzApp");
                                    _nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
                                }
                                //@notice override this function
                                function _nonblockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual;
                                function retryMessage(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public payable virtual {
                                    // assert there is message to retry
                                    bytes32 payloadHash = failedMessages[_srcChainId][_srcAddress][_nonce];
                                    require(payloadHash != bytes32(0), "NonblockingLzApp: no stored message");
                                    require(keccak256(_payload) == payloadHash, "NonblockingLzApp: invalid payload");
                                    // clear the stored message
                                    failedMessages[_srcChainId][_srcAddress][_nonce] = bytes32(0);
                                    // execute the message. revert if it fails again
                                    _nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
                                    emit RetryMessageSuccess(_srcChainId, _srcAddress, _nonce, payloadHash);
                                }
                            }
                            // 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);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (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 functionCallWithValue(target, data, 0, "Address: low-level call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                                 * `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(
                                    address target,
                                    bytes memory data,
                                    string memory errorMessage
                                ) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, 0, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but also transferring `value` wei to `target`.
                                 *
                                 * Requirements:
                                 *
                                 * - the calling contract must have an ETH balance of at least `value`.
                                 * - the called Solidity function must be `payable`.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(
                                    address target,
                                    bytes memory data,
                                    uint256 value
                                ) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                                 * with `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(
                                    address target,
                                    bytes memory data,
                                    uint256 value,
                                    string memory errorMessage
                                ) internal returns (bytes memory) {
                                    require(address(this).balance >= value, "Address: insufficient balance for call");
                                    (bool success, bytes memory returndata) = target.call{value: value}(data);
                                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but performing a static call.
                                 *
                                 * _Available since v3.3._
                                 */
                                function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                                    return functionStaticCall(target, data, "Address: low-level static call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                                 * but performing a static call.
                                 *
                                 * _Available since v3.3._
                                 */
                                function functionStaticCall(
                                    address target,
                                    bytes memory data,
                                    string memory errorMessage
                                ) internal view returns (bytes memory) {
                                    (bool success, bytes memory returndata) = target.staticcall(data);
                                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but performing a delegate call.
                                 *
                                 * _Available since v3.4._
                                 */
                                function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                                    return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                                 * but performing a delegate call.
                                 *
                                 * _Available since v3.4._
                                 */
                                function functionDelegateCall(
                                    address target,
                                    bytes memory data,
                                    string memory errorMessage
                                ) internal returns (bytes memory) {
                                    (bool success, bytes memory returndata) = target.delegatecall(data);
                                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
                                 * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
                                 *
                                 * _Available since v4.8._
                                 */
                                function verifyCallResultFromTarget(
                                    address target,
                                    bool success,
                                    bytes memory returndata,
                                    string memory errorMessage
                                ) internal view returns (bytes memory) {
                                    if (success) {
                                        if (returndata.length == 0) {
                                            // only check isContract if the call was successful and the return data is empty
                                            // otherwise we already know that it was a contract
                                            require(isContract(target), "Address: call to non-contract");
                                        }
                                        return returndata;
                                    } else {
                                        _revert(returndata, errorMessage);
                                    }
                                }
                                /**
                                 * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
                                 * revert reason or using the provided one.
                                 *
                                 * _Available since v4.3._
                                 */
                                function verifyCallResult(
                                    bool success,
                                    bytes memory returndata,
                                    string memory errorMessage
                                ) internal pure returns (bytes memory) {
                                    if (success) {
                                        return returndata;
                                    } else {
                                        _revert(returndata, errorMessage);
                                    }
                                }
                                function _revert(bytes memory returndata, string memory errorMessage) private pure {
                                    // Look for revert reason and bubble it up if present
                                    if (returndata.length > 0) {
                                        // The easiest way to bubble the revert reason is using memory via assembly
                                        /// @solidity memory-safe-assembly
                                        assembly {
                                            let returndata_size := mload(returndata)
                                            revert(add(32, returndata), returndata_size)
                                        }
                                    } else {
                                        revert(errorMessage);
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // 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);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.8.0) (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");
                                    }
                                }
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.6.0;
                            pragma experimental ABIEncoderV2;
                            library LzLib {
                                // LayerZero communication
                                struct CallParams {
                                    address payable refundAddress;
                                    address zroPaymentAddress;
                                }
                                //---------------------------------------------------------------------------
                                // Address type handling
                                struct AirdropParams {
                                    uint airdropAmount;
                                    bytes32 airdropAddress;
                                }
                                function buildAdapterParams(LzLib.AirdropParams memory _airdropParams, uint _uaGasLimit) internal pure returns (bytes memory adapterParams) {
                                    if (_airdropParams.airdropAmount == 0 && _airdropParams.airdropAddress == bytes32(0x0)) {
                                        adapterParams = buildDefaultAdapterParams(_uaGasLimit);
                                    } else {
                                        adapterParams = buildAirdropAdapterParams(_uaGasLimit, _airdropParams);
                                    }
                                }
                                // Build Adapter Params
                                function buildDefaultAdapterParams(uint _uaGas) internal pure returns (bytes memory) {
                                    // txType 1
                                    // bytes  [2       32      ]
                                    // fields [txType  extraGas]
                                    return abi.encodePacked(uint16(1), _uaGas);
                                }
                                function buildAirdropAdapterParams(uint _uaGas, AirdropParams memory _params) internal pure returns (bytes memory) {
                                    require(_params.airdropAmount > 0, "Airdrop amount must be greater than 0");
                                    require(_params.airdropAddress != bytes32(0x0), "Airdrop address must be set");
                                    // txType 2
                                    // bytes  [2       32        32            bytes[]         ]
                                    // fields [txType  extraGas  dstNativeAmt  dstNativeAddress]
                                    return abi.encodePacked(uint16(2), _uaGas, _params.airdropAmount, _params.airdropAddress);
                                }
                                function getGasLimit(bytes memory _adapterParams) internal pure returns (uint gasLimit) {
                                    require(_adapterParams.length == 34 || _adapterParams.length > 66, "Invalid adapterParams");
                                    assembly {
                                        gasLimit := mload(add(_adapterParams, 34))
                                    }
                                }
                                // Decode Adapter Params
                                function decodeAdapterParams(bytes memory _adapterParams) internal pure returns (uint16 txType, uint uaGas, uint airdropAmount, address payable airdropAddress) {
                                    require(_adapterParams.length == 34 || _adapterParams.length > 66, "Invalid adapterParams");
                                    assembly {
                                        txType := mload(add(_adapterParams, 2))
                                        uaGas := mload(add(_adapterParams, 34))
                                    }
                                    require(txType == 1 || txType == 2, "Unsupported txType");
                                    require(uaGas > 0, "Gas too low");
                                    if (txType == 2) {
                                        assembly {
                                            airdropAmount := mload(add(_adapterParams, 66))
                                            airdropAddress := mload(add(_adapterParams, 86))
                                        }
                                    }
                                }
                                //---------------------------------------------------------------------------
                                // Address type handling
                                function bytes32ToAddress(bytes32 _bytes32Address) internal pure returns (address _address) {
                                    return address(uint160(uint(_bytes32Address)));
                                }
                                function addressToBytes32(address _address) internal pure returns (bytes32 _bytes32Address) {
                                    return bytes32(uint(uint160(_address)));
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.17;
                            import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
                            import {NonblockingLzApp} from "@layerzerolabs/solidity-examples/contracts/lzApp/NonblockingLzApp.sol";
                            /// @dev An abstract contract containing a common functionality used by OriginalTokenBridge and WrappedTokenBridge
                            abstract contract TokenBridgeBase is NonblockingLzApp, ReentrancyGuard {
                                /// @notice A packet type used to identify messages requesting minting of wrapped tokens
                                uint8 public constant PT_MINT = 0;
                                /// @notice A packet type used to identify messages requesting unlocking of original tokens
                                uint8 public constant PT_UNLOCK = 1;
                                bool public useCustomAdapterParams;
                                event SetUseCustomAdapterParams(bool useCustomAdapterParams);
                                constructor(address _endpoint) NonblockingLzApp(_endpoint) {}
                                /// @notice Sets the `useCustomAdapterParams` flag indicating whether the contract uses custom adapter parameters or the default ones
                                /// @dev Can be called only by the bridge owner
                                function setUseCustomAdapterParams(bool _useCustomAdapterParams) external onlyOwner {
                                    useCustomAdapterParams = _useCustomAdapterParams;
                                    emit SetUseCustomAdapterParams(_useCustomAdapterParams);
                                }
                                /// @dev Checks `adapterParams` for correctness
                                function _checkAdapterParams(uint16 dstChainId, uint16 pkType, bytes memory adapterParams) internal virtual {
                                    if (useCustomAdapterParams) {
                                        _checkGasLimit(dstChainId, pkType, adapterParams, 0);
                                    } else {
                                        require(adapterParams.length == 0, "TokenBridgeBase: adapterParams must be empty");
                                    }
                                }
                                /// @dev Overrides the renounce ownership logic inherited from openZeppelin `Ownable`
                                function renounceOwnership() public override onlyOwner {}
                            }// SPDX-License-Identifier: MIT
                            pragma solidity ^0.8.17;
                            /// @title Interface for WETH and other wrapped native gas tokens (e.g., WBNB, WAVAX, etc.)
                            interface IWETH {
                                /// @notice Deposit ether to get wrapped ether
                                function deposit() external payable;
                                /// @notice Withdraw wrapped ether to get ether
                                function withdraw(uint) external;
                            }

                            File 2 of 10: FiatTokenProxy
                            pragma solidity ^0.4.24;
                            
                            // File: zos-lib/contracts/upgradeability/Proxy.sol
                            
                            /**
                             * @title Proxy
                             * @dev Implements delegation of calls to other contracts, with proper
                             * forwarding of return values and bubbling of failures.
                             * It defines a fallback function that delegates all calls to the address
                             * returned by the abstract _implementation() internal function.
                             */
                            contract Proxy {
                              /**
                               * @dev Fallback function.
                               * Implemented entirely in `_fallback`.
                               */
                              function () payable external {
                                _fallback();
                              }
                            
                              /**
                               * @return The Address of the implementation.
                               */
                              function _implementation() internal view returns (address);
                            
                              /**
                               * @dev Delegates execution to an implementation contract.
                               * This is a low level function that doesn't return to its internal call site.
                               * It will return to the external caller whatever the implementation returns.
                               * @param implementation Address to delegate.
                               */
                              function _delegate(address implementation) internal {
                                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 Function that is run as the first thing in the fallback function.
                               * Can be redefined in derived contracts to add functionality.
                               * Redefinitions must call super._willFallback().
                               */
                              function _willFallback() internal {
                              }
                            
                              /**
                               * @dev fallback implementation.
                               * Extracted to enable manual triggering.
                               */
                              function _fallback() internal {
                                _willFallback();
                                _delegate(_implementation());
                              }
                            }
                            
                            // File: openzeppelin-solidity/contracts/AddressUtils.sol
                            
                            /**
                             * Utility library of inline functions on addresses
                             */
                            library AddressUtils {
                            
                              /**
                               * Returns whether the target address is a contract
                               * @dev This function will return false if invoked during the constructor of a contract,
                               * as the code is not actually created until after the constructor finishes.
                               * @param addr address to check
                               * @return whether the target address is a contract
                               */
                              function isContract(address addr) internal view returns (bool) {
                                uint256 size;
                                // XXX Currently there is no better way to check if there is a contract in an address
                                // than to check the size of the code at that address.
                                // See https://ethereum.stackexchange.com/a/14016/36603
                                // for more details about how this works.
                                // TODO Check this again before the Serenity release, because all addresses will be
                                // contracts then.
                                // solium-disable-next-line security/no-inline-assembly
                                assembly { size := extcodesize(addr) }
                                return size > 0;
                              }
                            
                            }
                            
                            // File: zos-lib/contracts/upgradeability/UpgradeabilityProxy.sol
                            
                            /**
                             * @title UpgradeabilityProxy
                             * @dev This contract implements a proxy that allows to change the
                             * implementation address to which it will delegate.
                             * Such a change is called an implementation upgrade.
                             */
                            contract UpgradeabilityProxy is Proxy {
                              /**
                               * @dev Emitted when the implementation is upgraded.
                               * @param implementation Address of the new implementation.
                               */
                              event Upgraded(address implementation);
                            
                              /**
                               * @dev Storage slot with the address of the current implementation.
                               * This is the keccak-256 hash of "org.zeppelinos.proxy.implementation", and is
                               * validated in the constructor.
                               */
                              bytes32 private constant IMPLEMENTATION_SLOT = 0x7050c9e0f4ca769c69bd3a8ef740bc37934f8e2c036e5a723fd8ee048ed3f8c3;
                            
                              /**
                               * @dev Contract constructor.
                               * @param _implementation Address of the initial implementation.
                               */
                              constructor(address _implementation) public {
                                assert(IMPLEMENTATION_SLOT == keccak256("org.zeppelinos.proxy.implementation"));
                            
                                _setImplementation(_implementation);
                              }
                            
                              /**
                               * @dev Returns the current implementation.
                               * @return Address of the current implementation
                               */
                              function _implementation() internal view returns (address impl) {
                                bytes32 slot = IMPLEMENTATION_SLOT;
                                assembly {
                                  impl := sload(slot)
                                }
                              }
                            
                              /**
                               * @dev Upgrades the proxy to a new implementation.
                               * @param newImplementation Address of the new implementation.
                               */
                              function _upgradeTo(address newImplementation) internal {
                                _setImplementation(newImplementation);
                                emit Upgraded(newImplementation);
                              }
                            
                              /**
                               * @dev Sets the implementation address of the proxy.
                               * @param newImplementation Address of the new implementation.
                               */
                              function _setImplementation(address newImplementation) private {
                                require(AddressUtils.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address");
                            
                                bytes32 slot = IMPLEMENTATION_SLOT;
                            
                                assembly {
                                  sstore(slot, newImplementation)
                                }
                              }
                            }
                            
                            // File: zos-lib/contracts/upgradeability/AdminUpgradeabilityProxy.sol
                            
                            /**
                             * @title AdminUpgradeabilityProxy
                             * @dev This contract combines an upgradeability proxy with an authorization
                             * mechanism for administrative tasks.
                             * All external functions in this contract must be guarded by the
                             * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
                             * feature proposal that would enable this to be done automatically.
                             */
                            contract AdminUpgradeabilityProxy is UpgradeabilityProxy {
                              /**
                               * @dev Emitted when the administration has been transferred.
                               * @param previousAdmin Address of the previous admin.
                               * @param newAdmin Address of the new admin.
                               */
                              event AdminChanged(address previousAdmin, address newAdmin);
                            
                              /**
                               * @dev Storage slot with the admin of the contract.
                               * This is the keccak-256 hash of "org.zeppelinos.proxy.admin", and is
                               * validated in the constructor.
                               */
                              bytes32 private constant ADMIN_SLOT = 0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b;
                            
                              /**
                               * @dev Modifier to check whether the `msg.sender` is the admin.
                               * If it is, it will run the function. Otherwise, it will delegate the call
                               * to the implementation.
                               */
                              modifier ifAdmin() {
                                if (msg.sender == _admin()) {
                                  _;
                                } else {
                                  _fallback();
                                }
                              }
                            
                              /**
                               * Contract constructor.
                               * It sets the `msg.sender` as the proxy administrator.
                               * @param _implementation address of the initial implementation.
                               */
                              constructor(address _implementation) UpgradeabilityProxy(_implementation) public {
                                assert(ADMIN_SLOT == keccak256("org.zeppelinos.proxy.admin"));
                            
                                _setAdmin(msg.sender);
                              }
                            
                              /**
                               * @return The address of the proxy admin.
                               */
                              function admin() external view ifAdmin returns (address) {
                                return _admin();
                              }
                            
                              /**
                               * @return The address of the implementation.
                               */
                              function implementation() external view ifAdmin returns (address) {
                                return _implementation();
                              }
                            
                              /**
                               * @dev Changes the admin of the proxy.
                               * Only the current admin can call this function.
                               * @param newAdmin Address to transfer proxy administration to.
                               */
                              function changeAdmin(address newAdmin) external ifAdmin {
                                require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
                                emit AdminChanged(_admin(), newAdmin);
                                _setAdmin(newAdmin);
                              }
                            
                              /**
                               * @dev Upgrade the backing implementation of the proxy.
                               * Only the admin can call this function.
                               * @param newImplementation Address of the new implementation.
                               */
                              function upgradeTo(address newImplementation) external ifAdmin {
                                _upgradeTo(newImplementation);
                              }
                            
                              /**
                               * @dev Upgrade the backing implementation of the proxy and call a function
                               * on the new implementation.
                               * This is useful to initialize the proxied contract.
                               * @param newImplementation Address of the new implementation.
                               * @param data Data to send as msg.data in the low level call.
                               * It should include the signature and the parameters of the function to be
                               * called, as described in
                               * https://solidity.readthedocs.io/en/develop/abi-spec.html#function-selector-and-argument-encoding.
                               */
                              function upgradeToAndCall(address newImplementation, bytes data) payable external ifAdmin {
                                _upgradeTo(newImplementation);
                                require(address(this).call.value(msg.value)(data));
                              }
                            
                              /**
                               * @return The admin slot.
                               */
                              function _admin() internal view returns (address adm) {
                                bytes32 slot = ADMIN_SLOT;
                                assembly {
                                  adm := sload(slot)
                                }
                              }
                            
                              /**
                               * @dev Sets the address of the proxy admin.
                               * @param newAdmin Address of the new proxy admin.
                               */
                              function _setAdmin(address newAdmin) internal {
                                bytes32 slot = ADMIN_SLOT;
                            
                                assembly {
                                  sstore(slot, newAdmin)
                                }
                              }
                            
                              /**
                               * @dev Only fall back when the sender is not the admin.
                               */
                              function _willFallback() internal {
                                require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
                                super._willFallback();
                              }
                            }
                            
                            // File: contracts/FiatTokenProxy.sol
                            
                            /**
                            * Copyright CENTRE SECZ 2018
                            *
                            * Permission is hereby granted, free of charge, to any person obtaining a copy 
                            * of this software and associated documentation files (the "Software"), to deal 
                            * in the Software without restriction, including without limitation the rights 
                            * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
                            * copies of the Software, and to permit persons to whom the Software is furnished to 
                            * do so, subject to the following conditions:
                            *
                            * The above copyright notice and this permission notice shall be included in all 
                            * copies or substantial portions of the Software.
                            *
                            * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
                            * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
                            * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
                            * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
                            * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 
                            * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
                            */
                            
                            pragma solidity ^0.4.24;
                            
                            
                            /**
                             * @title FiatTokenProxy
                             * @dev This contract proxies FiatToken calls and enables FiatToken upgrades
                            */ 
                            contract FiatTokenProxy is AdminUpgradeabilityProxy {
                                constructor(address _implementation) public AdminUpgradeabilityProxy(_implementation) {
                                }
                            }

                            File 3 of 10: OptimizedTransparentUpgradeableProxy
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            /**
                             * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
                             * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
                             * be specified by overriding the virtual {_implementation} function.
                             * 
                             * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
                             * different contract through the {_delegate} function.
                             * 
                             * The success and return data of the delegated call will be returned back to the caller of the proxy.
                             */
                            abstract contract Proxy {
                                /**
                                 * @dev Delegates the current call to `implementation`.
                                 * 
                                 * This function does not return to its internall call site, it will return directly to the external caller.
                                 */
                                function _delegate(address implementation) internal {
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        // Copy msg.data. We take full control of memory in this inline assembly
                                        // block because it will not return to Solidity code. We overwrite the
                                        // Solidity scratch pad at memory position 0.
                                        calldatacopy(0, 0, calldatasize())
                                        // Call the implementation.
                                        // out and outsize are 0 because we don't know the size yet.
                                        let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                                        // Copy the returned data.
                                        returndatacopy(0, 0, returndatasize())
                                        switch result
                                        // delegatecall returns 0 on error.
                                        case 0 { revert(0, returndatasize()) }
                                        default { return(0, returndatasize()) }
                                    }
                                }
                                /**
                                 * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                                 * and {_fallback} should delegate.
                                 */
                                function _implementation() internal virtual view returns (address);
                                /**
                                 * @dev Delegates the current call to the address returned by `_implementation()`.
                                 * 
                                 * This function does not return to its internall call site, it will return directly to the external caller.
                                 */
                                function _fallback() internal {
                                    _beforeFallback();
                                    _delegate(_implementation());
                                }
                                /**
                                 * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                                 * function in the contract matches the call data.
                                 */
                                fallback () payable external {
                                    _fallback();
                                }
                                /**
                                 * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                                 * is empty.
                                 */
                                receive () payable external {
                                    _fallback();
                                }
                                /**
                                 * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                                 * call, or as part of the Solidity `fallback` or `receive` functions.
                                 * 
                                 * If overriden should call `super._beforeFallback()`.
                                 */
                                function _beforeFallback() internal virtual {
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            import "./Proxy.sol";
                            import "../utils/Address.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.
                             * 
                             * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
                             * {TransparentUpgradeableProxy}.
                             */
                            contract UpgradeableProxy is Proxy {
                                /**
                                 * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                                 * 
                                 * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                                 * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                                 */
                                constructor(address _logic, bytes memory _data) payable {
                                    assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                                    _setImplementation(_logic);
                                    if(_data.length > 0) {
                                        // solhint-disable-next-line avoid-low-level-calls
                                        (bool success,) = _logic.delegatecall(_data);
                                        require(success);
                                    }
                                }
                                /**
                                 * @dev Emitted when the implementation is upgraded.
                                 */
                                event Upgraded(address indexed implementation);
                                /**
                                 * @dev Storage slot with the address of the current implementation.
                                 * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                                /**
                                 * @dev Returns the current implementation address.
                                 */
                                function _implementation() internal override view returns (address impl) {
                                    bytes32 slot = _IMPLEMENTATION_SLOT;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        impl := sload(slot)
                                    }
                                }
                                /**
                                 * @dev Upgrades the proxy to a new implementation.
                                 * 
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeTo(address newImplementation) internal {
                                    _setImplementation(newImplementation);
                                    emit Upgraded(newImplementation);
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 implementation slot.
                                 */
                                function _setImplementation(address newImplementation) private {
                                    require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
                                    bytes32 slot = _IMPLEMENTATION_SLOT;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        sstore(slot, newImplementation)
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            /**
                             * @dev Collection of functions related to the address type
                             */
                            library Address {
                                /**
                                 * @dev Returns true if `account` is a contract.
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * It is unsafe to assume that an address for which this function returns
                                 * false is an externally-owned account (EOA) and not a contract.
                                 *
                                 * Among others, `isContract` will return false for the following
                                 * types of addresses:
                                 *
                                 *  - an externally-owned account
                                 *  - a contract in construction
                                 *  - an address where a contract will be created
                                 *  - an address where a contract lived, but was destroyed
                                 * ====
                                 */
                                function isContract(address account) internal view returns (bool) {
                                    // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
                                    // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
                                    // for accounts without code, i.e. `keccak256('')`
                                    bytes32 codehash;
                                    bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly { codehash := extcodehash(account) }
                                    return (codehash != accountHash && codehash != 0x0);
                                }
                                /**
                                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                                 * `recipient`, forwarding all available gas and reverting on errors.
                                 *
                                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                                 * imposed by `transfer`, making them unable to receive funds via
                                 * `transfer`. {sendValue} removes this limitation.
                                 *
                                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                                 *
                                 * IMPORTANT: because control is transferred to `recipient`, care must be
                                 * taken to not create reentrancy vulnerabilities. Consider using
                                 * {ReentrancyGuard} or the
                                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                                 */
                                function sendValue(address payable recipient, uint256 amount) internal {
                                    require(address(this).balance >= amount, "Address: insufficient balance");
                                    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                                    (bool success, ) = recipient.call{ value: amount }("");
                                    require(success, "Address: unable to send value, recipient may have reverted");
                                }
                                /**
                                 * @dev Performs a Solidity function call using a low level `call`. A
                                 * plain`call` is an unsafe replacement for a function call: use this
                                 * function instead.
                                 *
                                 * If `target` reverts with a revert reason, it is bubbled up by this
                                 * function (like regular Solidity function calls).
                                 *
                                 * Returns the raw returned data. To convert to the expected return value,
                                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                                 *
                                 * Requirements:
                                 *
                                 * - `target` must be a contract.
                                 * - calling `target` with `data` must not revert.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                                  return functionCall(target, data, "Address: low-level call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                                 * `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                                    return _functionCallWithValue(target, data, 0, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but also transferring `value` wei to `target`.
                                 *
                                 * Requirements:
                                 *
                                 * - the calling contract must have an ETH balance of at least `value`.
                                 * - the called Solidity function must be `payable`.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                                 * with `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                                    require(address(this).balance >= value, "Address: insufficient balance for call");
                                    return _functionCallWithValue(target, data, value, errorMessage);
                                }
                                function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
                                    require(isContract(target), "Address: call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
                                    if (success) {
                                        return returndata;
                                    } else {
                                        // Look for revert reason and bubble it up if present
                                        if (returndata.length > 0) {
                                            // The easiest way to bubble the revert reason is using memory via assembly
                                            // solhint-disable-next-line no-inline-assembly
                                            assembly {
                                                let returndata_size := mload(returndata)
                                                revert(add(32, returndata), returndata_size)
                                            }
                                        } else {
                                            revert(errorMessage);
                                        }
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            import "../openzeppelin/proxy/UpgradeableProxy.sol";
                            /**
                             * @dev This contract implements a proxy that is upgradeable by an admin.
                             *
                             * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
                             * clashing], which can potentially be used in an attack, this contract uses the
                             * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
                             * things that go hand in hand:
                             *
                             * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
                             * that call matches one of the admin functions exposed by the proxy itself.
                             * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
                             * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
                             * "admin cannot fallback to proxy target".
                             *
                             * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
                             * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
                             * to sudden errors when trying to call a function from the proxy implementation.
                             *
                             * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
                             * you should think of the `ProxyAdmin` instance as the real administrative inerface of your proxy.
                             */
                            contract OptimizedTransparentUpgradeableProxy is UpgradeableProxy {
                                address internal immutable _ADMIN;
                                /**
                                 * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                                 * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
                                 */
                                constructor(
                                    address initialLogic,
                                    address initialAdmin,
                                    bytes memory _data
                                ) payable UpgradeableProxy(initialLogic, _data) {
                                    assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                                    bytes32 slot = _ADMIN_SLOT;
                                    _ADMIN = initialAdmin;
                                    // still store it to work with EIP-1967
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        sstore(slot, initialAdmin)
                                    }
                                }
                                /**
                                 * @dev Storage slot with the admin of the contract.
                                 * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                                /**
                                 * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                                 */
                                modifier ifAdmin() {
                                    if (msg.sender == _admin()) {
                                        _;
                                    } else {
                                        _fallback();
                                    }
                                }
                                /**
                                 * @dev Returns the current admin.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                                 *
                                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                                 * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                                 */
                                function admin() external ifAdmin returns (address) {
                                    return _admin();
                                }
                                /**
                                 * @dev Returns the current implementation.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                                 *
                                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                                 * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                                 */
                                function implementation() external ifAdmin returns (address) {
                                    return _implementation();
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                                 */
                                function upgradeTo(address newImplementation) external ifAdmin {
                                    _upgradeTo(newImplementation);
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                                 * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                                 * proxied contract.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                                 */
                                function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                                    _upgradeTo(newImplementation);
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, ) = newImplementation.delegatecall(data);
                                    require(success);
                                }
                                /**
                                 * @dev Returns the current admin.
                                 */
                                function _admin() internal view returns (address adm) {
                                    return _ADMIN;
                                }
                                /**
                                 * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                                 */
                                function _beforeFallback() internal virtual override {
                                    require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                                    super._beforeFallback();
                                }
                            }
                            

                            File 4 of 10: UltraLightNodeV2
                            {"Address.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize, which returns 0 for contracts in\n        // construction, since the code is only stored at the end of the\n        // constructor execution.\n\n        uint256 size;\n        // solhint-disable-next-line no-inline-assembly\n        assembly { size := extcodesize(account) }\n        return size \u003e 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity\u0027s `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance \u003e= amount, \"Address: insufficient balance\");\n\n        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\n        (bool success, ) = recipient.call{ value: amount }(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain`call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n      return functionCall(target, data, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n        require(address(this).balance \u003e= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.call{ value: value }(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            // Look for revert reason and bubble it up if present\n            if (returndata.length \u003e 0) {\n                // The easiest way to bubble the revert reason is using memory via assembly\n\n                // solhint-disable-next-line no-inline-assembly\n                assembly {\n                    let returndata_size := mload(returndata)\n                    revert(add(32, returndata), returndata_size)\n                }\n            } else {\n                revert(errorMessage);\n            }\n        }\n    }\n}\n"},"Buffer.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\n// https://github.com/ensdomains/buffer\n\npragma solidity ^0.7.0;\n\n/**\n * @dev A library for working with mutable byte buffers in Solidity.\n *\n * Byte buffers are mutable and expandable, and provide a variety of primitives\n * for writing to them. At any time you can fetch a bytes object containing the\n * current contents of the buffer. The bytes object should not be stored between\n * operations, as it may change due to resizing of the buffer.\n */\nlibrary Buffer {\n    /**\n     * @dev Represents a mutable buffer. Buffers have a current value (buf) and\n     *      a capacity. The capacity may be longer than the current value, in\n     *      which case it can be extended without the need to allocate more memory.\n     */\n    struct buffer {\n        bytes buf;\n        uint capacity;\n    }\n\n    /**\n     * @dev Initializes a buffer with an initial capacity.a co\n     * @param buf The buffer to initialize.\n     * @param capacity The number of bytes of space to allocate the buffer.\n     * @return The buffer, for chaining.\n     */\n    function init(buffer memory buf, uint capacity) internal pure returns (buffer memory) {\n        if (capacity % 32 != 0) {\n            capacity += 32 - (capacity % 32);\n        }\n        // Allocate space for the buffer data\n        buf.capacity = capacity;\n        assembly {\n            let ptr := mload(0x40)\n            mstore(buf, ptr)\n            mstore(ptr, 0)\n            mstore(0x40, add(32, add(ptr, capacity)))\n        }\n        return buf;\n    }\n\n\n    /**\n     * @dev Writes a byte string to a buffer. Resizes if doing so would exceed\n     *      the capacity of the buffer.\n     * @param buf The buffer to append to.\n     * @param off The start offset to write to.\n     * @param rawData The data to append.\n     * @param len The number of bytes to copy.\n     * @return The original buffer, for chaining.\n     */\n    function writeRawBytes(\n        buffer memory buf,\n        uint off,\n        bytes memory rawData,\n        uint offData,\n        uint len\n    ) internal pure returns (buffer memory) {\n        if (off + len \u003e buf.capacity) {\n            resize(buf, max(buf.capacity, len + off) * 2);\n        }\n\n        uint dest;\n        uint src;\n        assembly {\n            // Memory address of the buffer data\n            let bufptr := mload(buf)\n            // Length of existing buffer data\n            let buflen := mload(bufptr)\n            // Start address = buffer address + offset + sizeof(buffer length)\n            dest := add(add(bufptr, 32), off)\n            // Update buffer length if we\u0027re extending it\n            if gt(add(len, off), buflen) {\n                mstore(bufptr, add(len, off))\n            }\n            src := add(rawData, offData)\n        }\n\n        // Copy word-length chunks while possible\n        for (; len \u003e= 32; len -= 32) {\n            assembly {\n                mstore(dest, mload(src))\n            }\n            dest += 32;\n            src += 32;\n        }\n\n        // Copy remaining bytes\n        uint mask = 256**(32 - len) - 1;\n        assembly {\n            let srcpart := and(mload(src), not(mask))\n            let destpart := and(mload(dest), mask)\n            mstore(dest, or(destpart, srcpart))\n        }\n\n        return buf;\n    }\n\n    /**\n     * @dev Writes a byte string to a buffer. Resizes if doing so would exceed\n     *      the capacity of the buffer.\n     * @param buf The buffer to append to.\n     * @param off The start offset to write to.\n     * @param data The data to append.\n     * @param len The number of bytes to copy.\n     * @return The original buffer, for chaining.\n     */\n    function write(buffer memory buf, uint off, bytes memory data, uint len) internal pure returns (buffer memory) {\n        require(len \u003c= data.length);\n\n        if (off + len \u003e buf.capacity) {\n            resize(buf, max(buf.capacity, len + off) * 2);\n        }\n\n        uint dest;\n        uint src;\n        assembly {\n        // Memory address of the buffer data\n            let bufptr := mload(buf)\n        // Length of existing buffer data\n            let buflen := mload(bufptr)\n        // Start address = buffer address + offset + sizeof(buffer length)\n            dest := add(add(bufptr, 32), off)\n        // Update buffer length if we\u0027re extending it\n            if gt(add(len, off), buflen) {\n                mstore(bufptr, add(len, off))\n            }\n            src := add(data, 32)\n        }\n\n        // Copy word-length chunks while possible\n        for (; len \u003e= 32; len -= 32) {\n            assembly {\n                mstore(dest, mload(src))\n            }\n            dest += 32;\n            src += 32;\n        }\n\n        // Copy remaining bytes\n        uint mask = 256**(32 - len) - 1;\n        assembly {\n            let srcpart := and(mload(src), not(mask))\n            let destpart := and(mload(dest), mask)\n            mstore(dest, or(destpart, srcpart))\n        }\n\n        return buf;\n    }\n\n    function append(buffer memory buf, bytes memory data) internal pure returns (buffer memory) {\n        return write(buf, buf.buf.length, data, data.length);\n    }\n\n    function resize(buffer memory buf, uint capacity) private pure {\n        bytes memory oldbuf = buf.buf;\n        init(buf, capacity);\n        append(buf, oldbuf);\n    }\n\n    function max(uint a, uint b) private pure returns (uint) {\n        if (a \u003e b) {\n            return a;\n        }\n        return b;\n    }\n}\n"},"Context.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity \u003e=0.6.0 \u003c0.8.0;\n\n/*\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with GSN meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n    function _msgSender() internal view virtual returns (address payable) {\n        return msg.sender;\n    }\n\n    function _msgData() internal view virtual returns (bytes memory) {\n        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691\n        return msg.data;\n    }\n}\n"},"IERC20.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n    /**\n     * @dev Returns the amount of tokens in existence.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns the amount of tokens owned by `account`.\n     */\n    function balanceOf(address account) external view returns (uint256);\n\n    /**\n     * @dev Moves `amount` tokens from the caller\u0027s account to `recipient`.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transfer(address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Returns the remaining number of tokens that `spender` will be\n     * allowed to spend on behalf of `owner` through {transferFrom}. This is\n     * zero by default.\n     *\n     * This value changes when {approve} or {transferFrom} are called.\n     */\n    function allowance(address owner, address spender) external view returns (uint256);\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the caller\u0027s tokens.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * IMPORTANT: Beware that changing an allowance with this method brings the risk\n     * that someone may use both the old and the new allowance by unfortunate\n     * transaction ordering. One possible solution to mitigate this race\n     * condition is to first reduce the spender\u0027s allowance to 0 and set the\n     * desired value afterwards:\n     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address spender, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Moves `amount` tokens from `sender` to `recipient` using the\n     * allowance mechanism. `amount` is then deducted from the caller\u0027s\n     * allowance.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Emitted when `value` tokens are moved from one account (`from`) to\n     * another (`to`).\n     *\n     * Note that `value` may be zero.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 value);\n\n    /**\n     * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n     * a call to {approve}. `value` is the new allowance.\n     */\n    event Approval(address indexed owner, address indexed spender, uint256 value);\n}\n"},"ILayerZeroEndpoint.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\nimport \"./ILayerZeroUserApplicationConfig.sol\";\n\ninterface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {\n    // @notice send a LayerZero message to the specified address at a LayerZero endpoint.\n    // @param _dstChainId - the destination chain identifier\n    // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains\n    // @param _payload - a custom bytes payload to send to the destination contract\n    // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address\n    // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction\n    // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination\n    function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;\n\n    // @notice used by the messaging library to publish verified payload\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source contract (as bytes) at the source chain\n    // @param _dstAddress - the address on destination chain\n    // @param _nonce - the unbound message ordering nonce\n    // @param _gasLimit - the gas limit for external contract execution\n    // @param _payload - verified payload to send to the destination contract\n    function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;\n\n    // @notice get the inboundNonce of a receiver from a source chain which could be EVM or non-EVM chain\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source chain contract address\n    function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);\n\n    // @notice get the outboundNonce from this source chain which, consequently, is always an EVM\n    // @param _srcAddress - the source chain contract address\n    function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);\n\n    // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery\n    // @param _dstChainId - the destination chain identifier\n    // @param _userApplication - the user app address on this EVM chain\n    // @param _payload - the custom message to send over LayerZero\n    // @param _payInZRO - if false, user app pays the protocol fee in native token\n    // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain\n    function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);\n\n    // @notice get this Endpoint\u0027s immutable source identifier\n    function getChainId() external view returns (uint16);\n\n    // @notice the interface to retry failed message on this Endpoint destination\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source chain contract address\n    // @param _payload - the payload to be retried\n    function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;\n\n    // @notice query if any STORED payload (message blocking) at the endpoint.\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source chain contract address\n    function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);\n\n    // @notice query if the _libraryAddress is valid for sending msgs.\n    // @param _userApplication - the user app address on this EVM chain\n    function getSendLibraryAddress(address _userApplication) external view returns (address);\n\n    // @notice query if the _libraryAddress is valid for receiving msgs.\n    // @param _userApplication - the user app address on this EVM chain\n    function getReceiveLibraryAddress(address _userApplication) external view returns (address);\n\n    // @notice query if the non-reentrancy guard for send() is on\n    // @return true if the guard is on. false otherwise\n    function isSendingPayload() external view returns (bool);\n\n    // @notice query if the non-reentrancy guard for receive() is on\n    // @return true if the guard is on. false otherwise\n    function isReceivingPayload() external view returns (bool);\n\n    // @notice get the configuration of the LayerZero messaging library of the specified version\n    // @param _version - messaging library version\n    // @param _chainId - the chainId for the pending config change\n    // @param _userApplication - the contract address of the user application\n    // @param _configType - type of configuration. every messaging library has its own convention.\n    function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);\n\n    // @notice get the send() LayerZero messaging library version\n    // @param _userApplication - the contract address of the user application\n    function getSendVersion(address _userApplication) external view returns (uint16);\n\n    // @notice get the lzReceive() LayerZero messaging library version\n    // @param _userApplication - the contract address of the user application\n    function getReceiveVersion(address _userApplication) external view returns (uint16);\n}\n"},"ILayerZeroMessagingLibrary.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\nimport \"./ILayerZeroUserApplicationConfig.sol\";\n\ninterface ILayerZeroMessagingLibrary {\n    // send(), messages will be inflight.\n    function send(address _userApplication, uint64 _lastNonce, uint16 _chainId, bytes calldata _destination, bytes calldata _payload, address payable refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;\n\n    // estimate native fee at the send side\n    function estimateFees(uint16 _chainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);\n\n    //---------------------------------------------------------------------------\n    // setConfig / getConfig are User Application (UA) functions to specify Oracle, Relayer, blockConfirmations, libraryVersion\n    function setConfig(uint16 _chainId, address _userApplication, uint _configType, bytes calldata _config) external;\n\n    function getConfig(uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);\n}\n"},"ILayerZeroMessagingLibraryV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\nimport \"./ILayerZeroUserApplicationConfig.sol\";\nimport \"./ILayerZeroMessagingLibrary.sol\";\n\ninterface ILayerZeroMessagingLibraryV2 is ILayerZeroMessagingLibrary {\n    function getOutboundNonce(uint16 _chainId, bytes calldata _path) external view returns (uint64);\n}\n"},"ILayerZeroOracleV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\ninterface ILayerZeroOracleV2 {\n    // @notice query price and assign jobs at the same time\n    // @param _dstChainId - the destination endpoint identifier\n    // @param _outboundProofType - the proof type identifier to specify proof to be relayed\n    // @param _outboundBlockConfirmation - block confirmation delay before relaying blocks\n    // @param _userApplication - the source sending contract address\n    function assignJob(uint16 _dstChainId, uint16 _outboundProofType, uint64 _outboundBlockConfirmation, address _userApplication) external returns (uint price);\n\n    // @notice query the oracle price for relaying block information to the destination chain\n    // @param _dstChainId the destination endpoint identifier\n    // @param _outboundProofType the proof type identifier to specify the data to be relayed\n    // @param _outboundBlockConfirmation - block confirmation delay before relaying blocks\n    // @param _userApplication - the source sending contract address\n    function getFee(uint16 _dstChainId, uint16 _outboundProofType, uint64 _outboundBlockConfirmation, address _userApplication) external view returns (uint price);\n\n    // @notice withdraw the accrued fee in ultra light node\n    // @param _to - the fee receiver\n    // @param _amount - the withdrawal amount\n    function withdrawFee(address payable _to, uint _amount) external;\n}\n"},"ILayerZeroReceiver.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\ninterface ILayerZeroReceiver {\n    // @notice LayerZero endpoint will invoke this function to deliver the message on the destination\n    // @param _srcChainId - the source endpoint identifier\n    // @param _srcAddress - the source sending contract address from the source chain\n    // @param _nonce - the ordered message nonce\n    // @param _payload - the signed payload is the UA bytes has encoded to be sent\n    function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;\n}\n"},"ILayerZeroRelayerV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\ninterface ILayerZeroRelayerV2 {\n    // @notice query price and assign jobs at the same time\n    // @param _dstChainId - the destination endpoint identifier\n    // @param _outboundProofType - the proof type identifier to specify proof to be relayed\n    // @param _userApplication - the source sending contract address. relayers may apply price discrimination to user apps\n    // @param _payloadSize - the length of the payload. it is an indicator of gas usage for relaying cross-chain messages\n    // @param _adapterParams - optional parameters for extra service plugins, e.g. sending dust tokens at the destination chain\n    function assignJob(uint16 _dstChainId, uint16 _outboundProofType, address _userApplication, uint _payloadSize, bytes calldata _adapterParams) external returns (uint price);\n\n    // @notice query the relayer price for relaying the payload and its proof to the destination chain\n    // @param _dstChainId - the destination endpoint identifier\n    // @param _outboundProofType - the proof type identifier to specify proof to be relayed\n    // @param _userApplication - the source sending contract address. relayers may apply price discrimination to user apps\n    // @param _payloadSize - the length of the payload. it is an indicator of gas usage for relaying cross-chain messages\n    // @param _adapterParams - optional parameters for extra service plugins, e.g. sending dust tokens at the destination chain\n    function getFee(uint16 _dstChainId, uint16 _outboundProofType, address _userApplication, uint _payloadSize, bytes calldata _adapterParams) external view returns (uint price);\n\n    // @notice withdraw the accrued fee in ultra light node\n    // @param _to - the fee receiver\n    // @param _amount - the withdrawal amount\n    function withdrawFee(address payable _to, uint _amount) external;\n}\n"},"ILayerZeroTreasury.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\ninterface ILayerZeroTreasury {\n    function getFees(bool payInZro, uint relayerFee, uint oracleFee) external view returns (uint);\n}\n"},"ILayerZeroUltraLightNodeV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\npragma abicoder v2;\n\ninterface ILayerZeroUltraLightNodeV2 {\n    // Relayer functions\n    function validateTransactionProof(uint16 _srcChainId, address _dstAddress, uint _gasLimit, bytes32 _lookupHash, bytes32 _blockData, bytes calldata _transactionProof) external;\n\n    // an Oracle delivers the block data using updateHash()\n    function updateHash(uint16 _srcChainId, bytes32 _lookupHash, uint _confirmations, bytes32 _blockData) external;\n\n    // can only withdraw the receivable of the msg.sender\n    function withdrawNative(address payable _to, uint _amount) external;\n\n    function withdrawZRO(address _to, uint _amount) external;\n\n    // view functions\n    function getAppConfig(uint16 _remoteChainId, address _userApplicationAddress) external view returns (ApplicationConfiguration memory);\n\n    function accruedNativeFee(address _address) external view returns (uint);\n\n    struct ApplicationConfiguration {\n        uint16 inboundProofLibraryVersion;\n        uint64 inboundBlockConfirmations;\n        address relayer;\n        uint16 outboundProofType;\n        uint64 outboundBlockConfirmations;\n        address oracle;\n    }\n\n    event HashReceived(uint16 indexed srcChainId, address indexed oracle, bytes32 lookupHash, bytes32 blockData, uint confirmations);\n    event RelayerParams(bytes adapterParams, uint16 outboundProofType);\n    event Packet(bytes payload);\n    event InvalidDst(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);\n    event PacketReceived(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);\n    event AppConfigUpdated(address indexed userApplication, uint indexed configType, bytes newConfig);\n    event AddInboundProofLibraryForChain(uint16 indexed chainId, address lib);\n    event EnableSupportedOutboundProof(uint16 indexed chainId, uint16 proofType);\n    event SetChainAddressSize(uint16 indexed chainId, uint size);\n    event SetDefaultConfigForChainId(uint16 indexed chainId, uint16 inboundProofLib, uint64 inboundBlockConfirm, address relayer, uint16 outboundProofType, uint64 outboundBlockConfirm, address oracle);\n    event SetDefaultAdapterParamsForChainId(uint16 indexed chainId, uint16 indexed proofType, bytes adapterParams);\n    event SetLayerZeroToken(address indexed tokenAddress);\n    event SetRemoteUln(uint16 indexed chainId, bytes32 uln);\n    event SetTreasury(address indexed treasuryAddress);\n    event WithdrawZRO(address indexed msgSender, address indexed to, uint amount);\n    event WithdrawNative(address indexed msgSender, address indexed to, uint amount);\n}\n"},"ILayerZeroUserApplicationConfig.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\ninterface ILayerZeroUserApplicationConfig {\n    // @notice set the configuration of the LayerZero messaging library of the specified version\n    // @param _version - messaging library version\n    // @param _chainId - the chainId for the pending config change\n    // @param _configType - type of configuration. every messaging library has its own convention.\n    // @param _config - configuration in the bytes. can encode arbitrary content.\n    function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;\n\n    // @notice set the send() LayerZero messaging library version to _version\n    // @param _version - new messaging library version\n    function setSendVersion(uint16 _version) external;\n\n    // @notice set the lzReceive() LayerZero messaging library version to _version\n    // @param _version - new messaging library version\n    function setReceiveVersion(uint16 _version) external;\n\n    // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload\n    // @param _srcChainId - the chainId of the source chain\n    // @param _srcAddress - the contract address of the source contract at the source chain\n    function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;\n}\n"},"ILayerZeroValidationLibrary.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\npragma abicoder v2;\n\nimport \"./LayerZeroPacket.sol\";\n\ninterface ILayerZeroValidationLibrary {\n    function validateProof(bytes32 blockData, bytes calldata _data, uint _remoteAddressSize) external returns (LayerZeroPacket.Packet memory packet);\n}\n"},"LayerZeroPacket.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity 0.7.6;\n\nimport \"./Buffer.sol\";\nimport \"./SafeMath.sol\";\n\nlibrary LayerZeroPacket {\n    using Buffer for Buffer.buffer;\n    using SafeMath for uint;\n\n    struct Packet {\n        uint16 srcChainId;\n        uint16 dstChainId;\n        uint64 nonce;\n        address dstAddress;\n        bytes srcAddress;\n        bytes32 ulnAddress;\n        bytes payload;\n    }\n\n    function getPacket(\n        bytes memory data,\n        uint16 srcChain,\n        uint sizeOfSrcAddress,\n        bytes32 ulnAddress\n    ) internal pure returns (LayerZeroPacket.Packet memory) {\n        uint16 dstChainId;\n        address dstAddress;\n        uint size;\n        uint64 nonce;\n\n        // The log consists of the destination chain id and then a bytes payload\n        //      0--------------------------------------------31\n        // 0   |  total bytes size\n        // 32  |  destination chain id\n        // 64  |  bytes offset\n        // 96  |  bytes array size\n        // 128 |  payload\n        assembly {\n            dstChainId := mload(add(data, 32))\n            size := mload(add(data, 96)) /// size of the byte array\n            nonce := mload(add(data, 104)) // offset to convert to uint64  128  is index -24\n            dstAddress := mload(add(data, sub(add(128, sizeOfSrcAddress), 4))) // offset to convert to address 12 -8\n        }\n\n        Buffer.buffer memory srcAddressBuffer;\n        srcAddressBuffer.init(sizeOfSrcAddress);\n        srcAddressBuffer.writeRawBytes(0, data, 136, sizeOfSrcAddress); // 128 + 8\n\n        uint payloadSize = size.sub(28).sub(sizeOfSrcAddress);\n        Buffer.buffer memory payloadBuffer;\n        payloadBuffer.init(payloadSize);\n        payloadBuffer.writeRawBytes(0, data, sizeOfSrcAddress.add(156), payloadSize); // 148 + 8\n        return LayerZeroPacket.Packet(srcChain, dstChainId, nonce, dstAddress, srcAddressBuffer.buf, ulnAddress, payloadBuffer.buf);\n    }\n\n    function getPacketV2(\n        bytes memory data,\n        uint sizeOfSrcAddress,\n        bytes32 ulnAddress\n    ) internal pure returns (LayerZeroPacket.Packet memory) {\n        // packet def: abi.encodePacked(nonce, srcChain, srcAddress, dstChain, dstAddress, payload);\n        // data def: abi.encode(packet) = offset(32) + length(32) + packet\n        //              if from EVM\n        // 0 - 31       0 - 31          |  total bytes size\n        // 32 - 63      32 - 63         |  location\n        // 64 - 95      64 - 95         |  size of the packet\n        // 96 - 103     96 - 103        |  nonce\n        // 104 - 105    104 - 105       |  srcChainId\n        // 106 - P      106 - 125       |  srcAddress, where P = 106 + sizeOfSrcAddress - 1,\n        // P+1 - P+2    126 - 127       |  dstChainId\n        // P+3 - P+22   128 - 147       |  dstAddress\n        // P+23 - END   148 - END       |  payload\n\n        // decode the packet\n        uint256 realSize;\n        uint64 nonce;\n        uint16 srcChain;\n        uint16 dstChain;\n        address dstAddress;\n        assembly {\n            realSize := mload(add(data, 64))\n            nonce := mload(add(data, 72)) // 104 - 32\n            srcChain := mload(add(data, 74)) // 106 - 32\n            dstChain := mload(add(data, add(76, sizeOfSrcAddress))) // P + 3 - 32 = 105 + size + 3 - 32 = 76 + size\n            dstAddress := mload(add(data, add(96, sizeOfSrcAddress))) // P + 23 - 32 = 105 + size + 23 - 32 = 96 + size\n        }\n\n        require(srcChain != 0, \"LayerZeroPacket: invalid packet\");\n\n        Buffer.buffer memory srcAddressBuffer;\n        srcAddressBuffer.init(sizeOfSrcAddress);\n        srcAddressBuffer.writeRawBytes(0, data, 106, sizeOfSrcAddress);\n\n        uint nonPayloadSize = sizeOfSrcAddress.add(32);// 2 + 2 + 8 + 20, 32 + 20 = 52 if sizeOfSrcAddress == 20\n        uint payloadSize = realSize.sub(nonPayloadSize);\n        Buffer.buffer memory payloadBuffer;\n        payloadBuffer.init(payloadSize);\n        payloadBuffer.writeRawBytes(0, data, nonPayloadSize.add(96), payloadSize);\n\n        return LayerZeroPacket.Packet(srcChain, dstChain, nonce, dstAddress, srcAddressBuffer.buf, ulnAddress, payloadBuffer.buf);\n    }\n\n    function getPacketV3(\n        bytes memory data,\n        uint sizeOfSrcAddress,\n        bytes32 ulnAddress\n    ) internal pure returns (LayerZeroPacket.Packet memory) {\n        // data def: abi.encodePacked(nonce, srcChain, srcAddress, dstChain, dstAddress, payload);\n        //              if from EVM\n        // 0 - 31       0 - 31          |  total bytes size\n        // 32 - 39      32 - 39         |  nonce\n        // 40 - 41      40 - 41         |  srcChainId\n        // 42 - P       42 - 61         |  srcAddress, where P = 41 + sizeOfSrcAddress,\n        // P+1 - P+2    62 - 63         |  dstChainId\n        // P+3 - P+22   64 - 83         |  dstAddress\n        // P+23 - END   84 - END        |  payload\n\n        // decode the packet\n        uint256 realSize = data.length;\n        uint nonPayloadSize = sizeOfSrcAddress.add(32);// 2 + 2 + 8 + 20, 32 + 20 = 52 if sizeOfSrcAddress == 20\n        require(realSize \u003e= nonPayloadSize, \"LayerZeroPacket: invalid packet\");\n        uint payloadSize = realSize - nonPayloadSize;\n\n        uint64 nonce;\n        uint16 srcChain;\n        uint16 dstChain;\n        address dstAddress;\n        assembly {\n            nonce := mload(add(data, 8)) // 40 - 32\n            srcChain := mload(add(data, 10)) // 42 - 32\n            dstChain := mload(add(data, add(12, sizeOfSrcAddress))) // P + 3 - 32 = 41 + size + 3 - 32 = 12 + size\n            dstAddress := mload(add(data, add(32, sizeOfSrcAddress))) // P + 23 - 32 = 41 + size + 23 - 32 = 32 + size\n        }\n\n        require(srcChain != 0, \"LayerZeroPacket: invalid packet\");\n\n        Buffer.buffer memory srcAddressBuffer;\n        srcAddressBuffer.init(sizeOfSrcAddress);\n        srcAddressBuffer.writeRawBytes(0, data, 42, sizeOfSrcAddress);\n\n        Buffer.buffer memory payloadBuffer;\n        if (payloadSize \u003e 0) {\n            payloadBuffer.init(payloadSize);\n            payloadBuffer.writeRawBytes(0, data, nonPayloadSize.add(32), payloadSize);\n        }\n\n        return LayerZeroPacket.Packet(srcChain, dstChain, nonce, dstAddress, srcAddressBuffer.buf, ulnAddress, payloadBuffer.buf);\n    }\n}\n"},"NonceContract.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity 0.7.6;\n\nimport \"./ILayerZeroEndpoint.sol\";\n\ncontract NonceContract {\n    ILayerZeroEndpoint public immutable endpoint;\n    // outboundNonce = [dstChainId][remoteAddress + localAddress]\n    mapping(uint16 =\u003e mapping(bytes =\u003e uint64)) public outboundNonce;\n\n    constructor(address _endpoint) {\n        endpoint = ILayerZeroEndpoint(_endpoint);\n    }\n\n    function increment(uint16 _chainId, address _ua, bytes calldata _path) external returns (uint64) {\n        require(endpoint.getSendLibraryAddress(_ua) == msg.sender, \"NonceContract: msg.sender is not valid sendlibrary\");\n        return ++outboundNonce[_chainId][_path];\n    }\n}\n"},"Ownable.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\nimport \"./Context.sol\";\n/**\n * @dev Contract module which provides a basic access control mechanism, where\n * there is an account (an owner) that can be granted exclusive access to\n * specific functions.\n *\n * By default, the owner account will be the one that deploys the contract. This\n * can later be changed with {transferOwnership}.\n *\n * This module is used through inheritance. It will make available the modifier\n * `onlyOwner`, which can be applied to your functions to restrict their use to\n * the owner.\n */\nabstract contract Ownable is Context {\n    address private _owner;\n\n    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);\n\n    /**\n     * @dev Initializes the contract setting the deployer as the initial owner.\n     */\n    constructor () {\n        address msgSender = _msgSender();\n        _owner = msgSender;\n        emit OwnershipTransferred(address(0), msgSender);\n    }\n\n    /**\n     * @dev Returns the address of the current owner.\n     */\n    function owner() public view virtual returns (address) {\n        return _owner;\n    }\n\n    /**\n     * @dev Throws if called by any account other than the owner.\n     */\n    modifier onlyOwner() {\n        require(owner() == _msgSender(), \"Ownable: caller is not the owner\");\n        _;\n    }\n\n    /**\n     * @dev Leaves the contract without owner. It will not be possible to call\n     * `onlyOwner` functions anymore. Can only be called by the current owner.\n     *\n     * NOTE: Renouncing ownership will leave the contract without an owner,\n     * thereby removing any functionality that is only available to the owner.\n     */\n    function renounceOwnership() public virtual onlyOwner {\n        emit OwnershipTransferred(_owner, address(0));\n        _owner = address(0);\n    }\n\n    /**\n     * @dev Transfers ownership of the contract to a new account (`newOwner`).\n     * Can only be called by the current owner.\n     */\n    function transferOwnership(address newOwner) public virtual onlyOwner {\n        require(newOwner != address(0), \"Ownable: new owner is the zero address\");\n        emit OwnershipTransferred(_owner, newOwner);\n        _owner = newOwner;\n    }\n}\n"},"ReentrancyGuard.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Contract module that helps prevent reentrant calls to a function.\n *\n * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier\n * available, which can be applied to functions to make sure there are no nested\n * (reentrant) calls to them.\n *\n * Note that because there is a single `nonReentrant` guard, functions marked as\n * `nonReentrant` may not call one another. This can be worked around by making\n * those functions `private`, and then adding `external` `nonReentrant` entry\n * points to them.\n *\n * TIP: If you would like to learn more about reentrancy and alternative ways\n * to protect against it, check out our blog post\n * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].\n */\nabstract contract ReentrancyGuard {\n    // Booleans are more expensive than uint256 or any type that takes up a full\n    // word because each write operation emits an extra SLOAD to first read the\n    // slot\u0027s contents, replace the bits taken up by the boolean, and then write\n    // back. This is the compiler\u0027s defense against contract upgrades and\n    // pointer aliasing, and it cannot be disabled.\n\n    // The values being non-zero value makes deployment a bit more expensive,\n    // but in exchange the refund on every call to nonReentrant will be lower in\n    // amount. Since refunds are capped to a percentage of the total\n    // transaction\u0027s gas, it is best to keep them low in cases like this one, to\n    // increase the likelihood of the full refund coming into effect.\n    uint256 private constant _NOT_ENTERED = 1;\n    uint256 private constant _ENTERED = 2;\n\n    uint256 private _status;\n\n    constructor () {\n        _status = _NOT_ENTERED;\n    }\n\n    /**\n     * @dev Prevents a contract from calling itself, directly or indirectly.\n     * Calling a `nonReentrant` function from another `nonReentrant`\n     * function is not supported. It is possible to prevent this from happening\n     * by making the `nonReentrant` function external, and make it call a\n     * `private` function that does the actual work.\n     */\n    modifier nonReentrant() {\n        // On the first call to nonReentrant, _notEntered will be true\n        require(_status != _ENTERED, \"ReentrancyGuard: reentrant call\");\n\n        // Any calls to nonReentrant after this point will fail\n        _status = _ENTERED;\n\n        _;\n\n        // By storing the original value once again, a refund is triggered (see\n        // https://eips.ethereum.org/EIPS/eip-2200)\n        _status = _NOT_ENTERED;\n    }\n}\n"},"SafeERC20.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\nimport \"./IERC20.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n    using SafeMath for uint256;\n    using Address for address;\n\n    function safeTransfer(IERC20 token, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n    }\n\n    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n    }\n\n    /**\n     * @dev Deprecated. This function has issues similar to the ones found in\n     * {IERC20-approve}, and its usage is discouraged.\n     *\n     * Whenever possible, use {safeIncreaseAllowance} and\n     * {safeDecreaseAllowance} instead.\n     */\n    function safeApprove(IERC20 token, address spender, uint256 value) internal {\n        // safeApprove should only be called when setting an initial allowance,\n        // or when resetting it to zero. To increase and decrease it, use\n        // \u0027safeIncreaseAllowance\u0027 and \u0027safeDecreaseAllowance\u0027\n        // solhint-disable-next-line max-line-length\n        require((value == 0) || (token.allowance(address(this), spender) == 0),\n            \"SafeERC20: approve from non-zero to non-zero allowance\"\n        );\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n    }\n\n    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).add(value);\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).sub(value, \"SafeERC20: decreased allowance below zero\");\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    /**\n     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n     * on the return value: the return value is optional (but if data is returned, it must not be false).\n     * @param token The token targeted by the call.\n     * @param data The call data (encoded using abi.encode or one of its variants).\n     */\n    function _callOptionalReturn(IERC20 token, bytes memory data) private {\n        // We need to perform a low level call here, to bypass Solidity\u0027s return data size checking mechanism, since\n        // we\u0027re implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that\n        // the target address contains contract code and also asserts for success in the low-level call.\n\n        bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n        if (returndata.length \u003e 0) { // Return data is optional\n            // solhint-disable-next-line max-line-length\n            require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n        }\n    }\n}\n"},"SafeMath.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Wrappers over Solidity\u0027s arithmetic operations with added overflow\n * checks.\n *\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\n * in bugs, because programmers usually assume that an overflow raises an\n * error, which is the standard behavior in high level programming languages.\n * `SafeMath` restores this intuition by reverting the transaction when an\n * operation overflows.\n *\n * Using this library instead of the unchecked operations eliminates an entire\n * class of bugs, so it\u0027s recommended to use it always.\n */\nlibrary SafeMath {\n    /**\n     * @dev Returns the addition of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        uint256 c = a + b;\n        if (c \u003c a) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b \u003e a) return (false, 0);\n        return (true, a - b);\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        // Gas optimization: this is cheaper than requiring \u0027a\u0027 not being zero, but the\n        // benefit is lost if \u0027b\u0027 is also tested.\n        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n        if (a == 0) return (true, 0);\n        uint256 c = a * b;\n        if (c / a != b) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the division of two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a / b);\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a % b);\n    }\n\n    /**\n     * @dev Returns the addition of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity\u0027s `+` operator.\n     *\n     * Requirements:\n     *\n     * - Addition cannot overflow.\n     */\n    function add(uint256 a, uint256 b) internal pure returns (uint256) {\n        uint256 c = a + b;\n        require(c \u003e= a, \"SafeMath: addition overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting on\n     * overflow (when the result is negative).\n     *\n     * Counterpart to Solidity\u0027s `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003c= a, \"SafeMath: subtraction overflow\");\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity\u0027s `*` operator.\n     *\n     * Requirements:\n     *\n     * - Multiplication cannot overflow.\n     */\n    function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n        if (a == 0) return 0;\n        uint256 c = a * b;\n        require(c / a == b, \"SafeMath: multiplication overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting on\n     * division by zero. The result is rounded towards zero.\n     *\n     * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003e 0, \"SafeMath: division by zero\");\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting when dividing by zero.\n     *\n     * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003e 0, \"SafeMath: modulo by zero\");\n        return a % b;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n     * overflow (when the result is negative).\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {trySub}.\n     *\n     * Counterpart to Solidity\u0027s `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003c= a, errorMessage);\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n     * division by zero. The result is rounded towards zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryDiv}.\n     *\n     * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003e 0, errorMessage);\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting with custom message when dividing by zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryMod}.\n     *\n     * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003e 0, errorMessage);\n        return a % b;\n    }\n}\n"},"UltraLightNodeV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity 0.7.6;\npragma abicoder v2;\n\nimport \"./Ownable.sol\";\nimport \"./SafeMath.sol\";\nimport \"./ReentrancyGuard.sol\";\nimport \"./IERC20.sol\";\nimport \"./SafeERC20.sol\";\n\nimport \"./ILayerZeroValidationLibrary.sol\";\nimport \"./ILayerZeroReceiver.sol\";\nimport \"./ILayerZeroTreasury.sol\";\nimport \"./ILayerZeroEndpoint.sol\";\n// v2\nimport \"./ILayerZeroMessagingLibraryV2.sol\";\nimport \"./ILayerZeroOracleV2.sol\";\nimport \"./ILayerZeroUltraLightNodeV2.sol\";\nimport \"./ILayerZeroRelayerV2.sol\";\nimport \"./NonceContract.sol\";\n\ncontract UltraLightNodeV2 is ILayerZeroMessagingLibraryV2, ILayerZeroUltraLightNodeV2, ReentrancyGuard, Ownable {\n    using SafeERC20 for IERC20;\n    using SafeMath for uint;\n\n    // Application config\n    uint public constant CONFIG_TYPE_INBOUND_PROOF_LIBRARY_VERSION = 1;\n    uint public constant CONFIG_TYPE_INBOUND_BLOCK_CONFIRMATIONS = 2;\n    uint public constant CONFIG_TYPE_RELAYER = 3;\n    uint public constant CONFIG_TYPE_OUTBOUND_PROOF_TYPE = 4;\n    uint public constant CONFIG_TYPE_OUTBOUND_BLOCK_CONFIRMATIONS = 5;\n    uint public constant CONFIG_TYPE_ORACLE = 6;\n\n    // Token and Contracts\n    IERC20 public layerZeroToken;\n    ILayerZeroTreasury public treasuryContract;\n\n    mapping(address =\u003e uint) public nativeFees;\n    uint public treasuryZROFees;\n\n    // User Application\n    mapping(address =\u003e mapping(uint16 =\u003e ApplicationConfiguration)) public appConfig; // app address =\u003e chainId =\u003e config\n    mapping(uint16 =\u003e ApplicationConfiguration) public defaultAppConfig; // default UA settings if no version specified\n    mapping(uint16 =\u003e mapping(uint16 =\u003e bytes)) public defaultAdapterParams;\n\n    // Validation\n    mapping(uint16 =\u003e mapping(uint16 =\u003e address)) public inboundProofLibrary; // chainId =\u003e library Id =\u003e inboundProofLibrary contract\n    mapping(uint16 =\u003e uint16) public maxInboundProofLibrary; // chainId =\u003e inboundProofLibrary\n    mapping(uint16 =\u003e mapping(uint16 =\u003e bool)) public supportedOutboundProof; // chainId =\u003e outboundProofType =\u003e enabled\n    mapping(uint16 =\u003e uint) public chainAddressSizeMap;\n    mapping(address =\u003e mapping(uint16 =\u003e mapping(bytes32 =\u003e mapping(bytes32 =\u003e uint)))) public hashLookup; //[oracle][srcChainId][blockhash][datahash] -\u003e confirmation\n    mapping(uint16 =\u003e bytes32) public ulnLookup; // remote ulns\n\n    ILayerZeroEndpoint public immutable endpoint;\n    uint16 public immutable localChainId;\n    NonceContract public immutable nonceContract;\n\n    constructor(address _endpoint, address _nonceContract, uint16 _localChainId) {\n        require(_endpoint != address(0x0), \"LayerZero: endpoint cannot be zero address\");\n        require(_nonceContract != address(0x0), \"LayerZero: nonceContract cannot be zero address\");\n        ILayerZeroEndpoint lzEndpoint = ILayerZeroEndpoint(_endpoint);\n        localChainId = _localChainId;\n        endpoint = lzEndpoint;\n        nonceContract = NonceContract(_nonceContract);\n    }\n\n    // only the endpoint can call SEND() and setConfig()\n    modifier onlyEndpoint() {\n        require(address(endpoint) == msg.sender, \"LayerZero: only endpoint\");\n        _;\n    }\n\n    //----------------------------------------------------------------------------------\n    // PROTOCOL\n    function validateTransactionProof(uint16 _srcChainId, address _dstAddress, uint _gasLimit, bytes32 _lookupHash, bytes32 _blockData, bytes calldata _transactionProof) external override {\n        // retrieve UA\u0027s configuration using the _dstAddress from arguments.\n        ApplicationConfiguration memory uaConfig = _getAppConfig(_srcChainId, _dstAddress);\n\n        // assert that the caller == UA\u0027s relayer\n        require(uaConfig.relayer == msg.sender, \"LayerZero: invalid relayer\");\n\n        LayerZeroPacket.Packet memory _packet;\n        uint remoteAddressSize = chainAddressSizeMap[_srcChainId];\n        require(remoteAddressSize != 0, \"LayerZero: incorrect remote address size\");\n        {\n            // assert that the data submitted by UA\u0027s oracle have no fewer confirmations than UA\u0027s configuration\n            uint storedConfirmations = hashLookup[uaConfig.oracle][_srcChainId][_lookupHash][_blockData];\n            require(storedConfirmations \u003e 0 \u0026\u0026 storedConfirmations \u003e= uaConfig.inboundBlockConfirmations, \"LayerZero: not enough block confirmations\");\n\n            // decode\n            address inboundProofLib = inboundProofLibrary[_srcChainId][uaConfig.inboundProofLibraryVersion];\n            _packet = ILayerZeroValidationLibrary(inboundProofLib).validateProof(_blockData, _transactionProof, remoteAddressSize);\n        }\n\n        // packet content assertion\n        require(ulnLookup[_srcChainId] == _packet.ulnAddress \u0026\u0026 _packet.ulnAddress != bytes32(0), \"LayerZero: invalid _packet.ulnAddress\");\n        require(_packet.srcChainId == _srcChainId, \"LayerZero: invalid srcChain Id\");\n        // failsafe because the remoteAddress size being passed into validateProof trims the address this should not hit\n        require(_packet.srcAddress.length == remoteAddressSize, \"LayerZero: invalid srcAddress size\");\n        require(_packet.dstChainId == localChainId, \"LayerZero: invalid dstChain Id\");\n        require(_packet.dstAddress == _dstAddress, \"LayerZero: invalid dstAddress\");\n\n        // if the dst is not a contract, then emit and return early. This will break inbound nonces, but this particular\n        // path is already broken and wont ever be able to deliver anyways\n        if (!_isContract(_dstAddress)) {\n            emit InvalidDst(_packet.srcChainId, _packet.srcAddress, _packet.dstAddress, _packet.nonce, keccak256(_packet.payload));\n            return;\n        }\n\n        bytes memory pathData = abi.encodePacked(_packet.srcAddress, _packet.dstAddress);\n        emit PacketReceived(_packet.srcChainId, _packet.srcAddress, _packet.dstAddress, _packet.nonce, keccak256(_packet.payload));\n        endpoint.receivePayload(_srcChainId, pathData, _dstAddress, _packet.nonce, _gasLimit, _packet.payload);\n    }\n\n    function send(address _ua, uint64, uint16 _dstChainId, bytes calldata _path, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable override onlyEndpoint {\n        address ua = _ua;\n        uint16 dstChainId = _dstChainId;\n        require(ulnLookup[dstChainId] != bytes32(0), \"LayerZero: dstChainId does not exist\");\n\n        bytes memory dstAddress;\n        uint64 nonce;\n        // code block for solving \u0027Stack Too Deep\u0027\n        {\n            uint chainAddressSize = chainAddressSizeMap[dstChainId];\n            // path = remoteAddress + localAddress\n            require(chainAddressSize != 0 \u0026\u0026 _path.length == 20 + chainAddressSize, \"LayerZero: incorrect remote address size\");\n            address srcInPath;\n            bytes memory path = _path; // copy to memory\n            assembly {\n                srcInPath := mload(add(add(path, 20), chainAddressSize)) // chainAddressSize + 20\n            }\n            require(ua == srcInPath, \"LayerZero: wrong path data\");\n            dstAddress = _path[0:chainAddressSize];\n            nonce = nonceContract.increment(dstChainId, ua, path);\n        }\n\n        bytes memory payload = _payload;\n        ApplicationConfiguration memory uaConfig = _getAppConfig(dstChainId, ua);\n\n        // compute all the fees\n        uint relayerFee = _handleRelayer(dstChainId, uaConfig, ua, payload.length, _adapterParams);\n        uint oracleFee = _handleOracle(dstChainId, uaConfig, ua);\n        uint nativeProtocolFee = _handleProtocolFee(relayerFee, oracleFee, ua, _zroPaymentAddress);\n\n        // total native fee, does not include ZRO protocol fee\n        uint totalNativeFee = relayerFee.add(oracleFee).add(nativeProtocolFee);\n\n        // assert the user has attached enough native token for this address\n        require(totalNativeFee \u003c= msg.value, \"LayerZero: not enough native for fees\");\n        // refund if they send too much\n        uint amount = msg.value.sub(totalNativeFee);\n        if (amount \u003e 0) {\n            (bool success, ) = _refundAddress.call{value: amount}(\"\");\n            require(success, \"LayerZero: failed to refund\");\n        }\n\n        // emit the data packet\n        bytes memory encodedPayload = abi.encodePacked(nonce, localChainId, ua, dstChainId, dstAddress, payload);\n        emit Packet(encodedPayload);\n    }\n\n    function _handleRelayer(uint16 _dstChainId, ApplicationConfiguration memory _uaConfig, address _ua, uint _payloadSize, bytes memory _adapterParams) internal returns (uint relayerFee) {\n        if (_adapterParams.length == 0) {\n            _adapterParams = defaultAdapterParams[_dstChainId][_uaConfig.outboundProofType];\n        }\n        address relayerAddress = _uaConfig.relayer;\n        ILayerZeroRelayerV2 relayer = ILayerZeroRelayerV2(relayerAddress);\n        relayerFee = relayer.assignJob(_dstChainId, _uaConfig.outboundProofType, _ua, _payloadSize, _adapterParams);\n\n        _creditNativeFee(relayerAddress, relayerFee);\n\n        // emit the param events\n        emit RelayerParams(_adapterParams, _uaConfig.outboundProofType);\n    }\n\n    function _handleOracle(uint16 _dstChainId, ApplicationConfiguration memory _uaConfig, address _ua) internal returns (uint oracleFee) {\n        address oracleAddress = _uaConfig.oracle;\n        oracleFee = ILayerZeroOracleV2(oracleAddress).assignJob(_dstChainId, _uaConfig.outboundProofType, _uaConfig.outboundBlockConfirmations, _ua);\n\n        _creditNativeFee(oracleAddress, oracleFee);\n    }\n\n    function _handleProtocolFee(uint _relayerFee, uint _oracleFee, address _ua, address _zroPaymentAddress) internal returns (uint protocolNativeFee) {\n        // if no ZRO token or not specifying a payment address, pay in native token\n        bool payInNative = _zroPaymentAddress == address(0x0) || address(layerZeroToken) == address(0x0);\n        uint protocolFee = treasuryContract.getFees(!payInNative, _relayerFee, _oracleFee);\n\n        if (protocolFee \u003e 0) {\n            if (payInNative) {\n                address treasuryAddress = address(treasuryContract);\n                _creditNativeFee(treasuryAddress, protocolFee);\n                protocolNativeFee = protocolFee;\n            } else {\n                // zro payment address must equal the ua or the tx.origin otherwise the transaction reverts\n                require(_zroPaymentAddress == _ua || _zroPaymentAddress == tx.origin, \"LayerZero: must be paid by sender or origin\");\n\n                // transfer the LayerZero token to this contract from the payee\n                layerZeroToken.safeTransferFrom(_zroPaymentAddress, address(this), protocolFee);\n\n                treasuryZROFees = treasuryZROFees.add(protocolFee);\n            }\n        }\n    }\n\n    function _creditNativeFee(address _receiver, uint _amount) internal {\n        nativeFees[_receiver] = nativeFees[_receiver].add(_amount);\n    }\n\n    // Can be called by any address to update a block header\n    // can only upload new block data or the same block data with more confirmations\n    function updateHash(uint16 _srcChainId, bytes32 _lookupHash, uint _confirmations, bytes32 _blockData) external override {\n        uint storedConfirmations = hashLookup[msg.sender][_srcChainId][_lookupHash][_blockData];\n\n        // if it has a record, requires a larger confirmation.\n        require(storedConfirmations \u003c _confirmations, \"LayerZero: oracle data can only update if it has more confirmations\");\n\n        // set the new information into storage\n        hashLookup[msg.sender][_srcChainId][_lookupHash][_blockData] = _confirmations;\n\n        emit HashReceived(_srcChainId, msg.sender, _lookupHash, _blockData, _confirmations);\n    }\n\n    //----------------------------------------------------------------------------------\n    // Other Library Interfaces\n\n    // default to DEFAULT setting if ZERO value\n    function getAppConfig(uint16 _remoteChainId, address _ua) external view override returns (ApplicationConfiguration memory) {\n        return _getAppConfig(_remoteChainId, _ua);\n    }\n\n    function _getAppConfig(uint16 _remoteChainId, address _ua) internal view returns (ApplicationConfiguration memory) {\n        ApplicationConfiguration memory config = appConfig[_ua][_remoteChainId];\n        ApplicationConfiguration storage defaultConfig = defaultAppConfig[_remoteChainId];\n\n        if (config.inboundProofLibraryVersion == 0) {\n            config.inboundProofLibraryVersion = defaultConfig.inboundProofLibraryVersion;\n        }\n\n        if (config.inboundBlockConfirmations == 0) {\n            config.inboundBlockConfirmations = defaultConfig.inboundBlockConfirmations;\n        }\n\n        if (config.relayer == address(0x0)) {\n            config.relayer = defaultConfig.relayer;\n        }\n\n        if (config.outboundProofType == 0) {\n            config.outboundProofType = defaultConfig.outboundProofType;\n        }\n\n        if (config.outboundBlockConfirmations == 0) {\n            config.outboundBlockConfirmations = defaultConfig.outboundBlockConfirmations;\n        }\n\n        if (config.oracle == address(0x0)) {\n            config.oracle = defaultConfig.oracle;\n        }\n\n        return config;\n    }\n\n    function setConfig(uint16 _remoteChainId, address _ua, uint _configType, bytes calldata _config) external override onlyEndpoint {\n        ApplicationConfiguration storage uaConfig = appConfig[_ua][_remoteChainId];\n        if (_configType == CONFIG_TYPE_INBOUND_PROOF_LIBRARY_VERSION) {\n            uint16 inboundProofLibraryVersion = abi.decode(_config, (uint16));\n            require(inboundProofLibraryVersion \u003c= maxInboundProofLibrary[_remoteChainId], \"LayerZero: invalid inbound proof library version\");\n            uaConfig.inboundProofLibraryVersion = inboundProofLibraryVersion;\n        } else if (_configType == CONFIG_TYPE_INBOUND_BLOCK_CONFIRMATIONS) {\n            uint64 blockConfirmations = abi.decode(_config, (uint64));\n            uaConfig.inboundBlockConfirmations = blockConfirmations;\n        } else if (_configType == CONFIG_TYPE_RELAYER) {\n            address relayer = abi.decode(_config, (address));\n            uaConfig.relayer = relayer;\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_PROOF_TYPE) {\n            uint16 outboundProofType = abi.decode(_config, (uint16));\n            require(supportedOutboundProof[_remoteChainId][outboundProofType] || outboundProofType == 0, \"LayerZero: invalid outbound proof type\");\n            uaConfig.outboundProofType = outboundProofType;\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_BLOCK_CONFIRMATIONS) {\n            uint64 blockConfirmations = abi.decode(_config, (uint64));\n            uaConfig.outboundBlockConfirmations = blockConfirmations;\n        } else if (_configType == CONFIG_TYPE_ORACLE) {\n            address oracle = abi.decode(_config, (address));\n            uaConfig.oracle = oracle;\n        } else {\n            revert(\"LayerZero: Invalid config type\");\n        }\n\n        emit AppConfigUpdated(_ua, _configType, _config);\n    }\n\n    function getConfig(uint16 _remoteChainId, address _ua, uint _configType) external view override returns (bytes memory) {\n        ApplicationConfiguration storage uaConfig = appConfig[_ua][_remoteChainId];\n\n        if (_configType == CONFIG_TYPE_INBOUND_PROOF_LIBRARY_VERSION) {\n            if (uaConfig.inboundProofLibraryVersion == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].inboundProofLibraryVersion);\n            }\n            return abi.encode(uaConfig.inboundProofLibraryVersion);\n        } else if (_configType == CONFIG_TYPE_INBOUND_BLOCK_CONFIRMATIONS) {\n            if (uaConfig.inboundBlockConfirmations == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].inboundBlockConfirmations);\n            }\n            return abi.encode(uaConfig.inboundBlockConfirmations);\n        } else if (_configType == CONFIG_TYPE_RELAYER) {\n            if (uaConfig.relayer == address(0x0)) {\n                return abi.encode(defaultAppConfig[_remoteChainId].relayer);\n            }\n            return abi.encode(uaConfig.relayer);\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_PROOF_TYPE) {\n            if (uaConfig.outboundProofType == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].outboundProofType);\n            }\n            return abi.encode(uaConfig.outboundProofType);\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_BLOCK_CONFIRMATIONS) {\n            if (uaConfig.outboundBlockConfirmations == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].outboundBlockConfirmations);\n            }\n            return abi.encode(uaConfig.outboundBlockConfirmations);\n        } else if (_configType == CONFIG_TYPE_ORACLE) {\n            if (uaConfig.oracle == address(0x0)) {\n                return abi.encode(defaultAppConfig[_remoteChainId].oracle);\n            }\n            return abi.encode(uaConfig.oracle);\n        } else {\n            revert(\"LayerZero: Invalid config type\");\n        }\n    }\n\n    // returns the native fee the UA pays to cover fees\n    function estimateFees(uint16 _dstChainId, address _ua, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParams) external view override returns (uint nativeFee, uint zroFee) {\n        ApplicationConfiguration memory uaConfig = _getAppConfig(_dstChainId, _ua);\n\n        // Relayer Fee\n        bytes memory adapterParams;\n        if (_adapterParams.length \u003e 0) {\n            adapterParams = _adapterParams;\n        } else {\n            adapterParams = defaultAdapterParams[_dstChainId][uaConfig.outboundProofType];\n        }\n        uint relayerFee = ILayerZeroRelayerV2(uaConfig.relayer).getFee(_dstChainId, uaConfig.outboundProofType, _ua, _payload.length, adapterParams);\n\n        // Oracle Fee\n        address ua = _ua; // stack too deep\n        uint oracleFee = ILayerZeroOracleV2(uaConfig.oracle).getFee(_dstChainId, uaConfig.outboundProofType, uaConfig.outboundBlockConfirmations, ua);\n\n        // LayerZero Fee\n        uint protocolFee = treasuryContract.getFees(_payInZRO, relayerFee, oracleFee);\n        _payInZRO ? zroFee = protocolFee : nativeFee = protocolFee;\n\n        // return the sum of fees\n        nativeFee = nativeFee.add(relayerFee).add(oracleFee);\n    }\n\n    //---------------------------------------------------------------------------\n    // Claim Fees\n\n    // universal withdraw ZRO token function\n    function withdrawZRO(address _to, uint _amount) external override nonReentrant {\n        require(msg.sender == address(treasuryContract), \"LayerZero: only treasury\");\n        treasuryZROFees = treasuryZROFees.sub(_amount);\n        layerZeroToken.safeTransfer(_to, _amount);\n        emit WithdrawZRO(msg.sender, _to, _amount);\n    }\n\n    // universal withdraw native token function.\n    // the source contract should perform all the authentication control\n    function withdrawNative(address payable _to, uint _amount) external override nonReentrant {\n        require(_to != address(0x0), \"LayerZero: _to cannot be zero address\");\n        nativeFees[msg.sender] = nativeFees[msg.sender].sub(_amount);\n\n        (bool success, ) = _to.call{value: _amount}(\"\");\n        require(success, \"LayerZero: withdraw failed\");\n        emit WithdrawNative(msg.sender, _to, _amount);\n    }\n\n    //---------------------------------------------------------------------------\n    // Owner calls, configuration only.\n    function setLayerZeroToken(address _layerZeroToken) external onlyOwner {\n        require(_layerZeroToken != address(0x0), \"LayerZero: _layerZeroToken cannot be zero address\");\n        layerZeroToken = IERC20(_layerZeroToken);\n        emit SetLayerZeroToken(_layerZeroToken);\n    }\n\n    function setTreasury(address _treasury) external onlyOwner {\n        require(_treasury != address(0x0), \"LayerZero: treasury cannot be zero address\");\n        treasuryContract = ILayerZeroTreasury(_treasury);\n        emit SetTreasury(_treasury);\n    }\n\n    function addInboundProofLibraryForChain(uint16 _chainId, address _library) external onlyOwner {\n        require(_library != address(0x0), \"LayerZero: library cannot be zero address\");\n        uint16 libId = maxInboundProofLibrary[_chainId];\n        require(libId \u003c 65535, \"LayerZero: can not add new library\");\n        maxInboundProofLibrary[_chainId] = ++libId;\n        inboundProofLibrary[_chainId][libId] = _library;\n        emit AddInboundProofLibraryForChain(_chainId, _library);\n    }\n\n    function enableSupportedOutboundProof(uint16 _chainId, uint16 _proofType) external onlyOwner {\n        supportedOutboundProof[_chainId][_proofType] = true;\n        emit EnableSupportedOutboundProof(_chainId, _proofType);\n    }\n\n    function setDefaultConfigForChainId(uint16 _chainId, uint16 _inboundProofLibraryVersion, uint64 _inboundBlockConfirmations, address _relayer, uint16 _outboundProofType, uint64 _outboundBlockConfirmations, address _oracle) external onlyOwner {\n        require(_inboundProofLibraryVersion \u003c= maxInboundProofLibrary[_chainId] \u0026\u0026 _inboundProofLibraryVersion \u003e 0, \"LayerZero: invalid inbound proof library version\");\n        require(_inboundBlockConfirmations \u003e 0, \"LayerZero: invalid inbound block confirmation\");\n        require(_relayer != address(0x0), \"LayerZero: invalid relayer address\");\n        require(supportedOutboundProof[_chainId][_outboundProofType], \"LayerZero: invalid outbound proof type\");\n        require(_outboundBlockConfirmations \u003e 0, \"LayerZero: invalid outbound block confirmation\");\n        require(_oracle != address(0x0), \"LayerZero: invalid oracle address\");\n        defaultAppConfig[_chainId] = ApplicationConfiguration(_inboundProofLibraryVersion, _inboundBlockConfirmations, _relayer, _outboundProofType, _outboundBlockConfirmations, _oracle);\n        emit SetDefaultConfigForChainId(_chainId, _inboundProofLibraryVersion, _inboundBlockConfirmations, _relayer, _outboundProofType, _outboundBlockConfirmations, _oracle);\n    }\n\n    function setDefaultAdapterParamsForChainId(uint16 _chainId, uint16 _proofType, bytes calldata _adapterParams) external onlyOwner {\n        defaultAdapterParams[_chainId][_proofType] = _adapterParams;\n        emit SetDefaultAdapterParamsForChainId(_chainId, _proofType, _adapterParams);\n    }\n\n    function setRemoteUln(uint16 _remoteChainId, bytes32 _remoteUln) external onlyOwner {\n        require(ulnLookup[_remoteChainId] == bytes32(0), \"LayerZero: remote uln already set\");\n        ulnLookup[_remoteChainId] = _remoteUln;\n        emit SetRemoteUln(_remoteChainId, _remoteUln);\n    }\n\n    function setChainAddressSize(uint16 _chainId, uint _size) external onlyOwner {\n        require(chainAddressSizeMap[_chainId] == 0, \"LayerZero: remote chain address size already set\");\n        chainAddressSizeMap[_chainId] = _size;\n        emit SetChainAddressSize(_chainId, _size);\n    }\n\n    //----------------------------------------------------------------------------------\n    // view functions\n\n    function accruedNativeFee(address _address) external view override returns (uint) {\n        return nativeFees[_address];\n    }\n\n    function getOutboundNonce(uint16 _chainId, bytes calldata _path) external view override returns (uint64) {\n        return nonceContract.outboundNonce(_chainId, _path);\n    }\n\n    function _isContract(address addr) internal view returns (bool) {\n        uint size;\n        assembly {\n            size := extcodesize(addr)\n        }\n        return size != 0;\n    }\n}\n"}}

                            File 5 of 10: OptimizedTransparentUpgradeableProxy
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            /**
                             * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
                             * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
                             * be specified by overriding the virtual {_implementation} function.
                             * 
                             * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
                             * different contract through the {_delegate} function.
                             * 
                             * The success and return data of the delegated call will be returned back to the caller of the proxy.
                             */
                            abstract contract Proxy {
                                /**
                                 * @dev Delegates the current call to `implementation`.
                                 * 
                                 * This function does not return to its internall call site, it will return directly to the external caller.
                                 */
                                function _delegate(address implementation) internal {
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        // Copy msg.data. We take full control of memory in this inline assembly
                                        // block because it will not return to Solidity code. We overwrite the
                                        // Solidity scratch pad at memory position 0.
                                        calldatacopy(0, 0, calldatasize())
                                        // Call the implementation.
                                        // out and outsize are 0 because we don't know the size yet.
                                        let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                                        // Copy the returned data.
                                        returndatacopy(0, 0, returndatasize())
                                        switch result
                                        // delegatecall returns 0 on error.
                                        case 0 { revert(0, returndatasize()) }
                                        default { return(0, returndatasize()) }
                                    }
                                }
                                /**
                                 * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                                 * and {_fallback} should delegate.
                                 */
                                function _implementation() internal virtual view returns (address);
                                /**
                                 * @dev Delegates the current call to the address returned by `_implementation()`.
                                 * 
                                 * This function does not return to its internall call site, it will return directly to the external caller.
                                 */
                                function _fallback() internal {
                                    _beforeFallback();
                                    _delegate(_implementation());
                                }
                                /**
                                 * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                                 * function in the contract matches the call data.
                                 */
                                fallback () payable external {
                                    _fallback();
                                }
                                /**
                                 * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                                 * is empty.
                                 */
                                receive () payable external {
                                    _fallback();
                                }
                                /**
                                 * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                                 * call, or as part of the Solidity `fallback` or `receive` functions.
                                 * 
                                 * If overriden should call `super._beforeFallback()`.
                                 */
                                function _beforeFallback() internal virtual {
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            import "./Proxy.sol";
                            import "../utils/Address.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.
                             * 
                             * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
                             * {TransparentUpgradeableProxy}.
                             */
                            contract UpgradeableProxy is Proxy {
                                /**
                                 * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                                 * 
                                 * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                                 * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                                 */
                                constructor(address _logic, bytes memory _data) payable {
                                    assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                                    _setImplementation(_logic);
                                    if(_data.length > 0) {
                                        // solhint-disable-next-line avoid-low-level-calls
                                        (bool success,) = _logic.delegatecall(_data);
                                        require(success);
                                    }
                                }
                                /**
                                 * @dev Emitted when the implementation is upgraded.
                                 */
                                event Upgraded(address indexed implementation);
                                /**
                                 * @dev Storage slot with the address of the current implementation.
                                 * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                                /**
                                 * @dev Returns the current implementation address.
                                 */
                                function _implementation() internal override view returns (address impl) {
                                    bytes32 slot = _IMPLEMENTATION_SLOT;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        impl := sload(slot)
                                    }
                                }
                                /**
                                 * @dev Upgrades the proxy to a new implementation.
                                 * 
                                 * Emits an {Upgraded} event.
                                 */
                                function _upgradeTo(address newImplementation) internal {
                                    _setImplementation(newImplementation);
                                    emit Upgraded(newImplementation);
                                }
                                /**
                                 * @dev Stores a new address in the EIP1967 implementation slot.
                                 */
                                function _setImplementation(address newImplementation) private {
                                    require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
                                    bytes32 slot = _IMPLEMENTATION_SLOT;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        sstore(slot, newImplementation)
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            /**
                             * @dev Collection of functions related to the address type
                             */
                            library Address {
                                /**
                                 * @dev Returns true if `account` is a contract.
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * It is unsafe to assume that an address for which this function returns
                                 * false is an externally-owned account (EOA) and not a contract.
                                 *
                                 * Among others, `isContract` will return false for the following
                                 * types of addresses:
                                 *
                                 *  - an externally-owned account
                                 *  - a contract in construction
                                 *  - an address where a contract will be created
                                 *  - an address where a contract lived, but was destroyed
                                 * ====
                                 */
                                function isContract(address account) internal view returns (bool) {
                                    // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
                                    // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
                                    // for accounts without code, i.e. `keccak256('')`
                                    bytes32 codehash;
                                    bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly { codehash := extcodehash(account) }
                                    return (codehash != accountHash && codehash != 0x0);
                                }
                                /**
                                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                                 * `recipient`, forwarding all available gas and reverting on errors.
                                 *
                                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                                 * imposed by `transfer`, making them unable to receive funds via
                                 * `transfer`. {sendValue} removes this limitation.
                                 *
                                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                                 *
                                 * IMPORTANT: because control is transferred to `recipient`, care must be
                                 * taken to not create reentrancy vulnerabilities. Consider using
                                 * {ReentrancyGuard} or the
                                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                                 */
                                function sendValue(address payable recipient, uint256 amount) internal {
                                    require(address(this).balance >= amount, "Address: insufficient balance");
                                    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                                    (bool success, ) = recipient.call{ value: amount }("");
                                    require(success, "Address: unable to send value, recipient may have reverted");
                                }
                                /**
                                 * @dev Performs a Solidity function call using a low level `call`. A
                                 * plain`call` is an unsafe replacement for a function call: use this
                                 * function instead.
                                 *
                                 * If `target` reverts with a revert reason, it is bubbled up by this
                                 * function (like regular Solidity function calls).
                                 *
                                 * Returns the raw returned data. To convert to the expected return value,
                                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                                 *
                                 * Requirements:
                                 *
                                 * - `target` must be a contract.
                                 * - calling `target` with `data` must not revert.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                                  return functionCall(target, data, "Address: low-level call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                                 * `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                                    return _functionCallWithValue(target, data, 0, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but also transferring `value` wei to `target`.
                                 *
                                 * Requirements:
                                 *
                                 * - the calling contract must have an ETH balance of at least `value`.
                                 * - the called Solidity function must be `payable`.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                                 * with `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                                    require(address(this).balance >= value, "Address: insufficient balance for call");
                                    return _functionCallWithValue(target, data, value, errorMessage);
                                }
                                function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
                                    require(isContract(target), "Address: call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
                                    if (success) {
                                        return returndata;
                                    } else {
                                        // Look for revert reason and bubble it up if present
                                        if (returndata.length > 0) {
                                            // The easiest way to bubble the revert reason is using memory via assembly
                                            // solhint-disable-next-line no-inline-assembly
                                            assembly {
                                                let returndata_size := mload(returndata)
                                                revert(add(32, returndata), returndata_size)
                                            }
                                        } else {
                                            revert(errorMessage);
                                        }
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            import "../openzeppelin/proxy/UpgradeableProxy.sol";
                            /**
                             * @dev This contract implements a proxy that is upgradeable by an admin.
                             *
                             * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
                             * clashing], which can potentially be used in an attack, this contract uses the
                             * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
                             * things that go hand in hand:
                             *
                             * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
                             * that call matches one of the admin functions exposed by the proxy itself.
                             * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
                             * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
                             * "admin cannot fallback to proxy target".
                             *
                             * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
                             * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
                             * to sudden errors when trying to call a function from the proxy implementation.
                             *
                             * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
                             * you should think of the `ProxyAdmin` instance as the real administrative inerface of your proxy.
                             */
                            contract OptimizedTransparentUpgradeableProxy is UpgradeableProxy {
                                address internal immutable _ADMIN;
                                /**
                                 * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                                 * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
                                 */
                                constructor(
                                    address initialLogic,
                                    address initialAdmin,
                                    bytes memory _data
                                ) payable UpgradeableProxy(initialLogic, _data) {
                                    assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                                    bytes32 slot = _ADMIN_SLOT;
                                    _ADMIN = initialAdmin;
                                    // still store it to work with EIP-1967
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        sstore(slot, initialAdmin)
                                    }
                                }
                                /**
                                 * @dev Storage slot with the admin of the contract.
                                 * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                                 * validated in the constructor.
                                 */
                                bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                                /**
                                 * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                                 */
                                modifier ifAdmin() {
                                    if (msg.sender == _admin()) {
                                        _;
                                    } else {
                                        _fallback();
                                    }
                                }
                                /**
                                 * @dev Returns the current admin.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                                 *
                                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                                 * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                                 */
                                function admin() external ifAdmin returns (address) {
                                    return _admin();
                                }
                                /**
                                 * @dev Returns the current implementation.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                                 *
                                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                                 * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                                 */
                                function implementation() external ifAdmin returns (address) {
                                    return _implementation();
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                                 */
                                function upgradeTo(address newImplementation) external ifAdmin {
                                    _upgradeTo(newImplementation);
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                                 * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                                 * proxied contract.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                                 */
                                function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                                    _upgradeTo(newImplementation);
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, ) = newImplementation.delegatecall(data);
                                    require(success);
                                }
                                /**
                                 * @dev Returns the current admin.
                                 */
                                function _admin() internal view returns (address adm) {
                                    return _ADMIN;
                                }
                                /**
                                 * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                                 */
                                function _beforeFallback() internal virtual override {
                                    require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                                    super._beforeFallback();
                                }
                            }
                            

                            File 6 of 10: FiatTokenV2_2
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { EIP712Domain } from "./EIP712Domain.sol"; // solhint-disable-line no-unused-import
                            import { Blacklistable } from "../v1/Blacklistable.sol"; // solhint-disable-line no-unused-import
                            import { FiatTokenV1 } from "../v1/FiatTokenV1.sol"; // solhint-disable-line no-unused-import
                            import { FiatTokenV2 } from "./FiatTokenV2.sol"; // solhint-disable-line no-unused-import
                            import { FiatTokenV2_1 } from "./FiatTokenV2_1.sol";
                            import { EIP712 } from "../util/EIP712.sol";
                            // solhint-disable func-name-mixedcase
                            /**
                             * @title FiatToken V2.2
                             * @notice ERC20 Token backed by fiat reserves, version 2.2
                             */
                            contract FiatTokenV2_2 is FiatTokenV2_1 {
                                /**
                                 * @notice Initialize v2.2
                                 * @param accountsToBlacklist   A list of accounts to migrate from the old blacklist
                                 * @param newSymbol             New token symbol
                                 * data structure to the new blacklist data structure.
                                 */
                                function initializeV2_2(
                                    address[] calldata accountsToBlacklist,
                                    string calldata newSymbol
                                ) external {
                                    // solhint-disable-next-line reason-string
                                    require(_initializedVersion == 2);
                                    // Update fiat token symbol
                                    symbol = newSymbol;
                                    // Add previously blacklisted accounts to the new blacklist data structure
                                    // and remove them from the old blacklist data structure.
                                    for (uint256 i = 0; i < accountsToBlacklist.length; i++) {
                                        require(
                                            _deprecatedBlacklisted[accountsToBlacklist[i]],
                                            "FiatTokenV2_2: Blacklisting previously unblacklisted account!"
                                        );
                                        _blacklist(accountsToBlacklist[i]);
                                        delete _deprecatedBlacklisted[accountsToBlacklist[i]];
                                    }
                                    _blacklist(address(this));
                                    delete _deprecatedBlacklisted[address(this)];
                                    _initializedVersion = 3;
                                }
                                /**
                                 * @dev Internal function to get the current chain id.
                                 * @return The current chain id.
                                 */
                                function _chainId() internal virtual view returns (uint256) {
                                    uint256 chainId;
                                    assembly {
                                        chainId := chainid()
                                    }
                                    return chainId;
                                }
                                /**
                                 * @inheritdoc EIP712Domain
                                 */
                                function _domainSeparator() internal override view returns (bytes32) {
                                    return EIP712.makeDomainSeparator(name, "2", _chainId());
                                }
                                /**
                                 * @notice Update allowance with a signed permit
                                 * @dev EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param owner       Token owner's address (Authorizer)
                                 * @param spender     Spender's address
                                 * @param value       Amount of allowance
                                 * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                                 * @param signature   Signature bytes signed by an EOA wallet or a contract wallet
                                 */
                                function permit(
                                    address owner,
                                    address spender,
                                    uint256 value,
                                    uint256 deadline,
                                    bytes memory signature
                                ) external whenNotPaused {
                                    _permit(owner, spender, value, deadline, signature);
                                }
                                /**
                                 * @notice Execute a transfer with a signed authorization
                                 * @dev EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                                 */
                                function transferWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    bytes memory signature
                                ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                                    _transferWithAuthorization(
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce,
                                        signature
                                    );
                                }
                                /**
                                 * @notice Receive a transfer with a signed authorization from the payer
                                 * @dev This has an additional check to ensure that the payee's address
                                 * matches the caller of this function to prevent front-running attacks.
                                 * EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                                 */
                                function receiveWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    bytes memory signature
                                ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                                    _receiveWithAuthorization(
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce,
                                        signature
                                    );
                                }
                                /**
                                 * @notice Attempt to cancel an authorization
                                 * @dev Works only if the authorization is not yet used.
                                 * EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                                 */
                                function cancelAuthorization(
                                    address authorizer,
                                    bytes32 nonce,
                                    bytes memory signature
                                ) external whenNotPaused {
                                    _cancelAuthorization(authorizer, nonce, signature);
                                }
                                /**
                                 * @dev Helper method that sets the blacklist state of an account on balanceAndBlacklistStates.
                                 * If _shouldBlacklist is true, we apply a (1 << 255) bitmask with an OR operation on the
                                 * account's balanceAndBlacklistState. This flips the high bit for the account to 1,
                                 * indicating that the account is blacklisted.
                                 *
                                 * If _shouldBlacklist if false, we reset the account's balanceAndBlacklistStates to their
                                 * balances. This clears the high bit for the account, indicating that the account is unblacklisted.
                                 * @param _account         The address of the account.
                                 * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
                                 */
                                function _setBlacklistState(address _account, bool _shouldBlacklist)
                                    internal
                                    override
                                {
                                    balanceAndBlacklistStates[_account] = _shouldBlacklist
                                        ? balanceAndBlacklistStates[_account] | (1 << 255)
                                        : _balanceOf(_account);
                                }
                                /**
                                 * @dev Helper method that sets the balance of an account on balanceAndBlacklistStates.
                                 * Since balances are stored in the last 255 bits of the balanceAndBlacklistStates value,
                                 * we need to ensure that the updated balance does not exceed (2^255 - 1).
                                 * Since blacklisted accounts' balances cannot be updated, the method will also
                                 * revert if the account is blacklisted
                                 * @param _account The address of the account.
                                 * @param _balance The new fiat token balance of the account (max: (2^255 - 1)).
                                 */
                                function _setBalance(address _account, uint256 _balance) internal override {
                                    require(
                                        _balance <= ((1 << 255) - 1),
                                        "FiatTokenV2_2: Balance exceeds (2^255 - 1)"
                                    );
                                    require(
                                        !_isBlacklisted(_account),
                                        "FiatTokenV2_2: Account is blacklisted"
                                    );
                                    balanceAndBlacklistStates[_account] = _balance;
                                }
                                /**
                                 * @inheritdoc Blacklistable
                                 */
                                function _isBlacklisted(address _account)
                                    internal
                                    override
                                    view
                                    returns (bool)
                                {
                                    return balanceAndBlacklistStates[_account] >> 255 == 1;
                                }
                                /**
                                 * @dev Helper method to obtain the balance of an account. Since balances
                                 * are stored in the last 255 bits of the balanceAndBlacklistStates value,
                                 * we apply a ((1 << 255) - 1) bit bitmask with an AND operation on the
                                 * balanceAndBlacklistState to obtain the balance.
                                 * @param _account  The address of the account.
                                 * @return          The fiat token balance of the account.
                                 */
                                function _balanceOf(address _account)
                                    internal
                                    override
                                    view
                                    returns (uint256)
                                {
                                    return balanceAndBlacklistStates[_account] & ((1 << 255) - 1);
                                }
                                /**
                                 * @inheritdoc FiatTokenV1
                                 */
                                function approve(address spender, uint256 value)
                                    external
                                    override
                                    whenNotPaused
                                    returns (bool)
                                {
                                    _approve(msg.sender, spender, value);
                                    return true;
                                }
                                /**
                                 * @inheritdoc FiatTokenV2
                                 */
                                function permit(
                                    address owner,
                                    address spender,
                                    uint256 value,
                                    uint256 deadline,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) external override whenNotPaused {
                                    _permit(owner, spender, value, deadline, v, r, s);
                                }
                                /**
                                 * @inheritdoc FiatTokenV2
                                 */
                                function increaseAllowance(address spender, uint256 increment)
                                    external
                                    override
                                    whenNotPaused
                                    returns (bool)
                                {
                                    _increaseAllowance(msg.sender, spender, increment);
                                    return true;
                                }
                                /**
                                 * @inheritdoc FiatTokenV2
                                 */
                                function decreaseAllowance(address spender, uint256 decrement)
                                    external
                                    override
                                    whenNotPaused
                                    returns (bool)
                                {
                                    _decreaseAllowance(msg.sender, spender, decrement);
                                    return true;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.6.2 <0.8.0;
                            /**
                             * @dev Collection of functions related to the address type
                             */
                            library Address {
                                /**
                                 * @dev Returns true if `account` is a contract.
                                 *
                                 * [IMPORTANT]
                                 * ====
                                 * It is unsafe to assume that an address for which this function returns
                                 * false is an externally-owned account (EOA) and not a contract.
                                 *
                                 * Among others, `isContract` will return false for the following
                                 * types of addresses:
                                 *
                                 *  - an externally-owned account
                                 *  - a contract in construction
                                 *  - an address where a contract will be created
                                 *  - an address where a contract lived, but was destroyed
                                 * ====
                                 */
                                function isContract(address account) internal view returns (bool) {
                                    // This method relies on extcodesize, which returns 0 for contracts in
                                    // construction, since the code is only stored at the end of the
                                    // constructor execution.
                                    uint256 size;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly { size := extcodesize(account) }
                                    return size > 0;
                                }
                                /**
                                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                                 * `recipient`, forwarding all available gas and reverting on errors.
                                 *
                                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                                 * imposed by `transfer`, making them unable to receive funds via
                                 * `transfer`. {sendValue} removes this limitation.
                                 *
                                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                                 *
                                 * IMPORTANT: because control is transferred to `recipient`, care must be
                                 * taken to not create reentrancy vulnerabilities. Consider using
                                 * {ReentrancyGuard} or the
                                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                                 */
                                function sendValue(address payable recipient, uint256 amount) internal {
                                    require(address(this).balance >= amount, "Address: insufficient balance");
                                    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                                    (bool success, ) = recipient.call{ value: amount }("");
                                    require(success, "Address: unable to send value, recipient may have reverted");
                                }
                                /**
                                 * @dev Performs a Solidity function call using a low level `call`. A
                                 * plain`call` is an unsafe replacement for a function call: use this
                                 * function instead.
                                 *
                                 * If `target` reverts with a revert reason, it is bubbled up by this
                                 * function (like regular Solidity function calls).
                                 *
                                 * Returns the raw returned data. To convert to the expected return value,
                                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                                 *
                                 * Requirements:
                                 *
                                 * - `target` must be a contract.
                                 * - calling `target` with `data` must not revert.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                                  return functionCall(target, data, "Address: low-level call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                                 * `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, 0, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but also transferring `value` wei to `target`.
                                 *
                                 * Requirements:
                                 *
                                 * - the calling contract must have an ETH balance of at least `value`.
                                 * - the called Solidity function must be `payable`.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                                    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                                 * with `errorMessage` as a fallback revert reason when `target` reverts.
                                 *
                                 * _Available since v3.1._
                                 */
                                function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                                    require(address(this).balance >= value, "Address: insufficient balance for call");
                                    require(isContract(target), "Address: call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.call{ value: value }(data);
                                    return _verifyCallResult(success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but performing a static call.
                                 *
                                 * _Available since v3.3._
                                 */
                                function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                                    return functionStaticCall(target, data, "Address: low-level static call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                                 * but performing a static call.
                                 *
                                 * _Available since v3.3._
                                 */
                                function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
                                    require(isContract(target), "Address: static call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.staticcall(data);
                                    return _verifyCallResult(success, returndata, errorMessage);
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                                 * but performing a delegate call.
                                 *
                                 * _Available since v3.4._
                                 */
                                function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                                    return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                                }
                                /**
                                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                                 * but performing a delegate call.
                                 *
                                 * _Available since v3.4._
                                 */
                                function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                                    require(isContract(target), "Address: delegate call to non-contract");
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, bytes memory returndata) = target.delegatecall(data);
                                    return _verifyCallResult(success, returndata, errorMessage);
                                }
                                function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
                                    if (success) {
                                        return returndata;
                                    } else {
                                        // Look for revert reason and bubble it up if present
                                        if (returndata.length > 0) {
                                            // The easiest way to bubble the revert reason is using memory via assembly
                                            // solhint-disable-next-line no-inline-assembly
                                            assembly {
                                                let returndata_size := mload(returndata)
                                                revert(add(32, returndata), returndata_size)
                                            }
                                        } else {
                                            revert(errorMessage);
                                        }
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.6.0 <0.8.0;
                            import "./IERC20.sol";
                            import "../../math/SafeMath.sol";
                            import "../../utils/Address.sol";
                            /**
                             * @title SafeERC20
                             * @dev Wrappers around ERC20 operations that throw on failure (when the token
                             * contract returns false). Tokens that return no value (and instead revert or
                             * throw on failure) are also supported, non-reverting calls are assumed to be
                             * successful.
                             * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
                             * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
                             */
                            library SafeERC20 {
                                using SafeMath for uint256;
                                using Address for address;
                                function safeTransfer(IERC20 token, address to, uint256 value) internal {
                                    _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                                }
                                function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
                                    _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                                }
                                /**
                                 * @dev Deprecated. This function has issues similar to the ones found in
                                 * {IERC20-approve}, and its usage is discouraged.
                                 *
                                 * Whenever possible, use {safeIncreaseAllowance} and
                                 * {safeDecreaseAllowance} instead.
                                 */
                                function safeApprove(IERC20 token, address spender, uint256 value) internal {
                                    // safeApprove should only be called when setting an initial allowance,
                                    // or when resetting it to zero. To increase and decrease it, use
                                    // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                                    // solhint-disable-next-line max-line-length
                                    require((value == 0) || (token.allowance(address(this), spender) == 0),
                                        "SafeERC20: approve from non-zero to non-zero allowance"
                                    );
                                    _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
                                }
                                function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                                    uint256 newAllowance = token.allowance(address(this), spender).add(value);
                                    _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                                }
                                function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                                    uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
                                    _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                                }
                                /**
                                 * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                                 * on the return value: the return value is optional (but if data is returned, it must not be false).
                                 * @param token The token targeted by the call.
                                 * @param data The call data (encoded using abi.encode or one of its variants).
                                 */
                                function _callOptionalReturn(IERC20 token, bytes memory data) private {
                                    // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                                    // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                                    // the target address contains contract code and also asserts for success in the low-level call.
                                    bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                                    if (returndata.length > 0) { // Return data is optional
                                        // solhint-disable-next-line max-line-length
                                        require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.6.0 <0.8.0;
                            /**
                             * @dev Interface of the ERC20 standard as defined in the EIP.
                             */
                            interface IERC20 {
                                /**
                                 * @dev Returns the amount of tokens in existence.
                                 */
                                function totalSupply() external view returns (uint256);
                                /**
                                 * @dev Returns the amount of tokens owned by `account`.
                                 */
                                function balanceOf(address account) external view returns (uint256);
                                /**
                                 * @dev Moves `amount` tokens from the caller's account to `recipient`.
                                 *
                                 * Returns a boolean value indicating whether the operation succeeded.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function transfer(address recipient, uint256 amount) external returns (bool);
                                /**
                                 * @dev Returns the remaining number of tokens that `spender` will be
                                 * allowed to spend on behalf of `owner` through {transferFrom}. This is
                                 * zero by default.
                                 *
                                 * This value changes when {approve} or {transferFrom} are called.
                                 */
                                function allowance(address owner, address spender) external view returns (uint256);
                                /**
                                 * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                                 *
                                 * Returns a boolean value indicating whether the operation succeeded.
                                 *
                                 * IMPORTANT: Beware that changing an allowance with this method brings the risk
                                 * that someone may use both the old and the new allowance by unfortunate
                                 * transaction ordering. One possible solution to mitigate this race
                                 * condition is to first reduce the spender's allowance to 0 and set the
                                 * desired value afterwards:
                                 * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                                 *
                                 * Emits an {Approval} event.
                                 */
                                function approve(address spender, uint256 amount) external returns (bool);
                                /**
                                 * @dev Moves `amount` tokens from `sender` to `recipient` using the
                                 * allowance mechanism. `amount` is then deducted from the caller's
                                 * allowance.
                                 *
                                 * Returns a boolean value indicating whether the operation succeeded.
                                 *
                                 * Emits a {Transfer} event.
                                 */
                                function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
                                /**
                                 * @dev Emitted when `value` tokens are moved from one account (`from`) to
                                 * another (`to`).
                                 *
                                 * Note that `value` may be zero.
                                 */
                                event Transfer(address indexed from, address indexed to, uint256 value);
                                /**
                                 * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                                 * a call to {approve}. `value` is the new allowance.
                                 */
                                event Approval(address indexed owner, address indexed spender, uint256 value);
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.6.0 <0.8.0;
                            /**
                             * @dev Wrappers over Solidity's arithmetic operations with added overflow
                             * checks.
                             *
                             * Arithmetic operations in Solidity wrap on overflow. This can easily result
                             * in bugs, because programmers usually assume that an overflow raises an
                             * error, which is the standard behavior in high level programming languages.
                             * `SafeMath` restores this intuition by reverting the transaction when an
                             * operation overflows.
                             *
                             * Using this library instead of the unchecked operations eliminates an entire
                             * class of bugs, so it's recommended to use it always.
                             */
                            library SafeMath {
                                /**
                                 * @dev Returns the addition of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    uint256 c = a + b;
                                    if (c < a) return (false, 0);
                                    return (true, c);
                                }
                                /**
                                 * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    if (b > a) return (false, 0);
                                    return (true, a - b);
                                }
                                /**
                                 * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                                    // benefit is lost if 'b' is also tested.
                                    // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                                    if (a == 0) return (true, 0);
                                    uint256 c = a * b;
                                    if (c / a != b) return (false, 0);
                                    return (true, c);
                                }
                                /**
                                 * @dev Returns the division of two unsigned integers, with a division by zero flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    if (b == 0) return (false, 0);
                                    return (true, a / b);
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    if (b == 0) return (false, 0);
                                    return (true, a % b);
                                }
                                /**
                                 * @dev Returns the addition of two unsigned integers, reverting on
                                 * overflow.
                                 *
                                 * Counterpart to Solidity's `+` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Addition cannot overflow.
                                 */
                                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                                    uint256 c = a + b;
                                    require(c >= a, "SafeMath: addition overflow");
                                    return c;
                                }
                                /**
                                 * @dev Returns the subtraction of two unsigned integers, reverting on
                                 * overflow (when the result is negative).
                                 *
                                 * Counterpart to Solidity's `-` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Subtraction cannot overflow.
                                 */
                                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                                    require(b <= a, "SafeMath: subtraction overflow");
                                    return a - b;
                                }
                                /**
                                 * @dev Returns the multiplication of two unsigned integers, reverting on
                                 * overflow.
                                 *
                                 * Counterpart to Solidity's `*` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Multiplication cannot overflow.
                                 */
                                function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                                    if (a == 0) return 0;
                                    uint256 c = a * b;
                                    require(c / a == b, "SafeMath: multiplication overflow");
                                    return c;
                                }
                                /**
                                 * @dev Returns the integer division of two unsigned integers, reverting on
                                 * division by zero. The result is rounded towards zero.
                                 *
                                 * Counterpart to Solidity's `/` operator. Note: this function uses a
                                 * `revert` opcode (which leaves remaining gas untouched) while Solidity
                                 * uses an invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function div(uint256 a, uint256 b) internal pure returns (uint256) {
                                    require(b > 0, "SafeMath: division by zero");
                                    return a / b;
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                                 * reverting when dividing by zero.
                                 *
                                 * Counterpart to Solidity's `%` operator. This function uses a `revert`
                                 * opcode (which leaves remaining gas untouched) while Solidity uses an
                                 * invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                                    require(b > 0, "SafeMath: modulo by zero");
                                    return a % b;
                                }
                                /**
                                 * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                                 * overflow (when the result is negative).
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {trySub}.
                                 *
                                 * Counterpart to Solidity's `-` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Subtraction cannot overflow.
                                 */
                                function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                    require(b <= a, errorMessage);
                                    return a - b;
                                }
                                /**
                                 * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                                 * division by zero. The result is rounded towards zero.
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {tryDiv}.
                                 *
                                 * Counterpart to Solidity's `/` operator. Note: this function uses a
                                 * `revert` opcode (which leaves remaining gas untouched) while Solidity
                                 * uses an invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                    require(b > 0, errorMessage);
                                    return a / b;
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                                 * reverting with custom message when dividing by zero.
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {tryMod}.
                                 *
                                 * Counterpart to Solidity's `%` operator. This function uses a `revert`
                                 * opcode (which leaves remaining gas untouched) while Solidity uses an
                                 * invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                    require(b > 0, errorMessage);
                                    return a % b;
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { FiatTokenV2 } from "./FiatTokenV2.sol";
                            // solhint-disable func-name-mixedcase
                            /**
                             * @title FiatToken V2.1
                             * @notice ERC20 Token backed by fiat reserves, version 2.1
                             */
                            contract FiatTokenV2_1 is FiatTokenV2 {
                                /**
                                 * @notice Initialize v2.1
                                 * @param lostAndFound  The address to which the locked funds are sent
                                 */
                                function initializeV2_1(address lostAndFound) external {
                                    // solhint-disable-next-line reason-string
                                    require(_initializedVersion == 1);
                                    uint256 lockedAmount = _balanceOf(address(this));
                                    if (lockedAmount > 0) {
                                        _transfer(address(this), lostAndFound, lockedAmount);
                                    }
                                    _blacklist(address(this));
                                    _initializedVersion = 2;
                                }
                                /**
                                 * @notice Version string for the EIP712 domain separator
                                 * @return Version string
                                 */
                                function version() external pure returns (string memory) {
                                    return "2";
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { FiatTokenV1_1 } from "../v1.1/FiatTokenV1_1.sol";
                            import { EIP712 } from "../util/EIP712.sol";
                            import { EIP3009 } from "./EIP3009.sol";
                            import { EIP2612 } from "./EIP2612.sol";
                            /**
                             * @title FiatToken V2
                             * @notice ERC20 Token backed by fiat reserves, version 2
                             */
                            contract FiatTokenV2 is FiatTokenV1_1, EIP3009, EIP2612 {
                                uint8 internal _initializedVersion;
                                /**
                                 * @notice Initialize v2
                                 * @param newName   New token name
                                 */
                                function initializeV2(string calldata newName) external {
                                    // solhint-disable-next-line reason-string
                                    require(initialized && _initializedVersion == 0);
                                    name = newName;
                                    _DEPRECATED_CACHED_DOMAIN_SEPARATOR = EIP712.makeDomainSeparator(
                                        newName,
                                        "2"
                                    );
                                    _initializedVersion = 1;
                                }
                                /**
                                 * @notice Increase the allowance by a given increment
                                 * @param spender   Spender's address
                                 * @param increment Amount of increase in allowance
                                 * @return True if successful
                                 */
                                function increaseAllowance(address spender, uint256 increment)
                                    external
                                    virtual
                                    whenNotPaused
                                    notBlacklisted(msg.sender)
                                    notBlacklisted(spender)
                                    returns (bool)
                                {
                                    _increaseAllowance(msg.sender, spender, increment);
                                    return true;
                                }
                                /**
                                 * @notice Decrease the allowance by a given decrement
                                 * @param spender   Spender's address
                                 * @param decrement Amount of decrease in allowance
                                 * @return True if successful
                                 */
                                function decreaseAllowance(address spender, uint256 decrement)
                                    external
                                    virtual
                                    whenNotPaused
                                    notBlacklisted(msg.sender)
                                    notBlacklisted(spender)
                                    returns (bool)
                                {
                                    _decreaseAllowance(msg.sender, spender, decrement);
                                    return true;
                                }
                                /**
                                 * @notice Execute a transfer with a signed authorization
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param v             v of the signature
                                 * @param r             r of the signature
                                 * @param s             s of the signature
                                 */
                                function transferWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                                    _transferWithAuthorization(
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce,
                                        v,
                                        r,
                                        s
                                    );
                                }
                                /**
                                 * @notice Receive a transfer with a signed authorization from the payer
                                 * @dev This has an additional check to ensure that the payee's address
                                 * matches the caller of this function to prevent front-running attacks.
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param v             v of the signature
                                 * @param r             r of the signature
                                 * @param s             s of the signature
                                 */
                                function receiveWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                                    _receiveWithAuthorization(
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce,
                                        v,
                                        r,
                                        s
                                    );
                                }
                                /**
                                 * @notice Attempt to cancel an authorization
                                 * @dev Works only if the authorization is not yet used.
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 * @param v             v of the signature
                                 * @param r             r of the signature
                                 * @param s             s of the signature
                                 */
                                function cancelAuthorization(
                                    address authorizer,
                                    bytes32 nonce,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) external whenNotPaused {
                                    _cancelAuthorization(authorizer, nonce, v, r, s);
                                }
                                /**
                                 * @notice Update allowance with a signed permit
                                 * @param owner       Token owner's address (Authorizer)
                                 * @param spender     Spender's address
                                 * @param value       Amount of allowance
                                 * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                                 * @param v           v of the signature
                                 * @param r           r of the signature
                                 * @param s           s of the signature
                                 */
                                function permit(
                                    address owner,
                                    address spender,
                                    uint256 value,
                                    uint256 deadline,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                )
                                    external
                                    virtual
                                    whenNotPaused
                                    notBlacklisted(owner)
                                    notBlacklisted(spender)
                                {
                                    _permit(owner, spender, value, deadline, v, r, s);
                                }
                                /**
                                 * @dev Internal function to increase the allowance by a given increment
                                 * @param owner     Token owner's address
                                 * @param spender   Spender's address
                                 * @param increment Amount of increase
                                 */
                                function _increaseAllowance(
                                    address owner,
                                    address spender,
                                    uint256 increment
                                ) internal override {
                                    _approve(owner, spender, allowed[owner][spender].add(increment));
                                }
                                /**
                                 * @dev Internal function to decrease the allowance by a given decrement
                                 * @param owner     Token owner's address
                                 * @param spender   Spender's address
                                 * @param decrement Amount of decrease
                                 */
                                function _decreaseAllowance(
                                    address owner,
                                    address spender,
                                    uint256 decrement
                                ) internal override {
                                    _approve(
                                        owner,
                                        spender,
                                        allowed[owner][spender].sub(
                                            decrement,
                                            "ERC20: decreased allowance below zero"
                                        )
                                    );
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            // solhint-disable func-name-mixedcase
                            /**
                             * @title EIP712 Domain
                             */
                            contract EIP712Domain {
                                // was originally DOMAIN_SEPARATOR
                                // but that has been moved to a method so we can override it in V2_2+
                                bytes32 internal _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
                                /**
                                 * @notice Get the EIP712 Domain Separator.
                                 * @return The bytes32 EIP712 domain separator.
                                 */
                                function DOMAIN_SEPARATOR() external view returns (bytes32) {
                                    return _domainSeparator();
                                }
                                /**
                                 * @dev Internal method to get the EIP712 Domain Separator.
                                 * @return The bytes32 EIP712 domain separator.
                                 */
                                function _domainSeparator() internal virtual view returns (bytes32) {
                                    return _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
                            import { EIP712Domain } from "./EIP712Domain.sol";
                            import { SignatureChecker } from "../util/SignatureChecker.sol";
                            import { MessageHashUtils } from "../util/MessageHashUtils.sol";
                            /**
                             * @title EIP-3009
                             * @notice Provide internal implementation for gas-abstracted transfers
                             * @dev Contracts that inherit from this must wrap these with publicly
                             * accessible functions, optionally adding modifiers where necessary
                             */
                            abstract contract EIP3009 is AbstractFiatTokenV2, EIP712Domain {
                                // keccak256("TransferWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
                                bytes32
                                    public constant TRANSFER_WITH_AUTHORIZATION_TYPEHASH = 0x7c7c6cdb67a18743f49ec6fa9b35f50d52ed05cbed4cc592e13b44501c1a2267;
                                // keccak256("ReceiveWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
                                bytes32
                                    public constant RECEIVE_WITH_AUTHORIZATION_TYPEHASH = 0xd099cc98ef71107a616c4f0f941f04c322d8e254fe26b3c6668db87aae413de8;
                                // keccak256("CancelAuthorization(address authorizer,bytes32 nonce)")
                                bytes32
                                    public constant CANCEL_AUTHORIZATION_TYPEHASH = 0x158b0a9edf7a828aad02f63cd515c68ef2f50ba807396f6d12842833a1597429;
                                /**
                                 * @dev authorizer address => nonce => bool (true if nonce is used)
                                 */
                                mapping(address => mapping(bytes32 => bool)) private _authorizationStates;
                                event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);
                                event AuthorizationCanceled(
                                    address indexed authorizer,
                                    bytes32 indexed nonce
                                );
                                /**
                                 * @notice Returns the state of an authorization
                                 * @dev Nonces are randomly generated 32-byte data unique to the
                                 * authorizer's address
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 * @return True if the nonce is used
                                 */
                                function authorizationState(address authorizer, bytes32 nonce)
                                    external
                                    view
                                    returns (bool)
                                {
                                    return _authorizationStates[authorizer][nonce];
                                }
                                /**
                                 * @notice Execute a transfer with a signed authorization
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param v             v of the signature
                                 * @param r             r of the signature
                                 * @param s             s of the signature
                                 */
                                function _transferWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) internal {
                                    _transferWithAuthorization(
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce,
                                        abi.encodePacked(r, s, v)
                                    );
                                }
                                /**
                                 * @notice Execute a transfer with a signed authorization
                                 * @dev EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                                 */
                                function _transferWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    bytes memory signature
                                ) internal {
                                    _requireValidAuthorization(from, nonce, validAfter, validBefore);
                                    _requireValidSignature(
                                        from,
                                        keccak256(
                                            abi.encode(
                                                TRANSFER_WITH_AUTHORIZATION_TYPEHASH,
                                                from,
                                                to,
                                                value,
                                                validAfter,
                                                validBefore,
                                                nonce
                                            )
                                        ),
                                        signature
                                    );
                                    _markAuthorizationAsUsed(from, nonce);
                                    _transfer(from, to, value);
                                }
                                /**
                                 * @notice Receive a transfer with a signed authorization from the payer
                                 * @dev This has an additional check to ensure that the payee's address
                                 * matches the caller of this function to prevent front-running attacks.
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param v             v of the signature
                                 * @param r             r of the signature
                                 * @param s             s of the signature
                                 */
                                function _receiveWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) internal {
                                    _receiveWithAuthorization(
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce,
                                        abi.encodePacked(r, s, v)
                                    );
                                }
                                /**
                                 * @notice Receive a transfer with a signed authorization from the payer
                                 * @dev This has an additional check to ensure that the payee's address
                                 * matches the caller of this function to prevent front-running attacks.
                                 * EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param from          Payer's address (Authorizer)
                                 * @param to            Payee's address
                                 * @param value         Amount to be transferred
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 * @param nonce         Unique nonce
                                 * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                                 */
                                function _receiveWithAuthorization(
                                    address from,
                                    address to,
                                    uint256 value,
                                    uint256 validAfter,
                                    uint256 validBefore,
                                    bytes32 nonce,
                                    bytes memory signature
                                ) internal {
                                    require(to == msg.sender, "FiatTokenV2: caller must be the payee");
                                    _requireValidAuthorization(from, nonce, validAfter, validBefore);
                                    _requireValidSignature(
                                        from,
                                        keccak256(
                                            abi.encode(
                                                RECEIVE_WITH_AUTHORIZATION_TYPEHASH,
                                                from,
                                                to,
                                                value,
                                                validAfter,
                                                validBefore,
                                                nonce
                                            )
                                        ),
                                        signature
                                    );
                                    _markAuthorizationAsUsed(from, nonce);
                                    _transfer(from, to, value);
                                }
                                /**
                                 * @notice Attempt to cancel an authorization
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 * @param v             v of the signature
                                 * @param r             r of the signature
                                 * @param s             s of the signature
                                 */
                                function _cancelAuthorization(
                                    address authorizer,
                                    bytes32 nonce,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) internal {
                                    _cancelAuthorization(authorizer, nonce, abi.encodePacked(r, s, v));
                                }
                                /**
                                 * @notice Attempt to cancel an authorization
                                 * @dev EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                                 */
                                function _cancelAuthorization(
                                    address authorizer,
                                    bytes32 nonce,
                                    bytes memory signature
                                ) internal {
                                    _requireUnusedAuthorization(authorizer, nonce);
                                    _requireValidSignature(
                                        authorizer,
                                        keccak256(
                                            abi.encode(CANCEL_AUTHORIZATION_TYPEHASH, authorizer, nonce)
                                        ),
                                        signature
                                    );
                                    _authorizationStates[authorizer][nonce] = true;
                                    emit AuthorizationCanceled(authorizer, nonce);
                                }
                                /**
                                 * @notice Validates that signature against input data struct
                                 * @param signer        Signer's address
                                 * @param dataHash      Hash of encoded data struct
                                 * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                                 */
                                function _requireValidSignature(
                                    address signer,
                                    bytes32 dataHash,
                                    bytes memory signature
                                ) private view {
                                    require(
                                        SignatureChecker.isValidSignatureNow(
                                            signer,
                                            MessageHashUtils.toTypedDataHash(_domainSeparator(), dataHash),
                                            signature
                                        ),
                                        "FiatTokenV2: invalid signature"
                                    );
                                }
                                /**
                                 * @notice Check that an authorization is unused
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 */
                                function _requireUnusedAuthorization(address authorizer, bytes32 nonce)
                                    private
                                    view
                                {
                                    require(
                                        !_authorizationStates[authorizer][nonce],
                                        "FiatTokenV2: authorization is used or canceled"
                                    );
                                }
                                /**
                                 * @notice Check that authorization is valid
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 * @param validAfter    The time after which this is valid (unix time)
                                 * @param validBefore   The time before which this is valid (unix time)
                                 */
                                function _requireValidAuthorization(
                                    address authorizer,
                                    bytes32 nonce,
                                    uint256 validAfter,
                                    uint256 validBefore
                                ) private view {
                                    require(
                                        now > validAfter,
                                        "FiatTokenV2: authorization is not yet valid"
                                    );
                                    require(now < validBefore, "FiatTokenV2: authorization is expired");
                                    _requireUnusedAuthorization(authorizer, nonce);
                                }
                                /**
                                 * @notice Mark an authorization as used
                                 * @param authorizer    Authorizer's address
                                 * @param nonce         Nonce of the authorization
                                 */
                                function _markAuthorizationAsUsed(address authorizer, bytes32 nonce)
                                    private
                                {
                                    _authorizationStates[authorizer][nonce] = true;
                                    emit AuthorizationUsed(authorizer, nonce);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
                            import { EIP712Domain } from "./EIP712Domain.sol";
                            import { MessageHashUtils } from "../util/MessageHashUtils.sol";
                            import { SignatureChecker } from "../util/SignatureChecker.sol";
                            /**
                             * @title EIP-2612
                             * @notice Provide internal implementation for gas-abstracted approvals
                             */
                            abstract contract EIP2612 is AbstractFiatTokenV2, EIP712Domain {
                                // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")
                                bytes32
                                    public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
                                mapping(address => uint256) private _permitNonces;
                                /**
                                 * @notice Nonces for permit
                                 * @param owner Token owner's address (Authorizer)
                                 * @return Next nonce
                                 */
                                function nonces(address owner) external view returns (uint256) {
                                    return _permitNonces[owner];
                                }
                                /**
                                 * @notice Verify a signed approval permit and execute if valid
                                 * @param owner     Token owner's address (Authorizer)
                                 * @param spender   Spender's address
                                 * @param value     Amount of allowance
                                 * @param deadline  The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                                 * @param v         v of the signature
                                 * @param r         r of the signature
                                 * @param s         s of the signature
                                 */
                                function _permit(
                                    address owner,
                                    address spender,
                                    uint256 value,
                                    uint256 deadline,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) internal {
                                    _permit(owner, spender, value, deadline, abi.encodePacked(r, s, v));
                                }
                                /**
                                 * @notice Verify a signed approval permit and execute if valid
                                 * @dev EOA wallet signatures should be packed in the order of r, s, v.
                                 * @param owner      Token owner's address (Authorizer)
                                 * @param spender    Spender's address
                                 * @param value      Amount of allowance
                                 * @param deadline   The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                                 * @param signature  Signature byte array signed by an EOA wallet or a contract wallet
                                 */
                                function _permit(
                                    address owner,
                                    address spender,
                                    uint256 value,
                                    uint256 deadline,
                                    bytes memory signature
                                ) internal {
                                    require(
                                        deadline == type(uint256).max || deadline >= now,
                                        "FiatTokenV2: permit is expired"
                                    );
                                    bytes32 typedDataHash = MessageHashUtils.toTypedDataHash(
                                        _domainSeparator(),
                                        keccak256(
                                            abi.encode(
                                                PERMIT_TYPEHASH,
                                                owner,
                                                spender,
                                                value,
                                                _permitNonces[owner]++,
                                                deadline
                                            )
                                        )
                                    );
                                    require(
                                        SignatureChecker.isValidSignatureNow(
                                            owner,
                                            typedDataHash,
                                            signature
                                        ),
                                        "EIP2612: invalid signature"
                                    );
                                    _approve(owner, spender, value);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { AbstractFiatTokenV1 } from "../v1/AbstractFiatTokenV1.sol";
                            abstract contract AbstractFiatTokenV2 is AbstractFiatTokenV1 {
                                function _increaseAllowance(
                                    address owner,
                                    address spender,
                                    uint256 increment
                                ) internal virtual;
                                function _decreaseAllowance(
                                    address owner,
                                    address spender,
                                    uint256 decrement
                                ) internal virtual;
                            }
                            /**
                             * SPDX-License-Identifier: MIT
                             *
                             * Copyright (c) 2016 Smart Contract Solutions, Inc.
                             * Copyright (c) 2018-2020 CENTRE SECZ
                             *
                             * Permission is hereby granted, free of charge, to any person obtaining a copy
                             * of this software and associated documentation files (the "Software"), to deal
                             * in the Software without restriction, including without limitation the rights
                             * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
                             * copies of the Software, and to permit persons to whom the Software is
                             * furnished to do so, subject to the following conditions:
                             *
                             * The above copyright notice and this permission notice shall be included in
                             * copies or substantial portions of the Software.
                             *
                             * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
                             * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
                             * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
                             * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
                             * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
                             * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
                             * SOFTWARE.
                             */
                            pragma solidity 0.6.12;
                            import { Ownable } from "./Ownable.sol";
                            /**
                             * @notice Base contract which allows children to implement an emergency stop
                             * mechanism
                             * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/feb665136c0dae9912e08397c1a21c4af3651ef3/contracts/lifecycle/Pausable.sol
                             * Modifications:
                             * 1. Added pauser role, switched pause/unpause to be onlyPauser (6/14/2018)
                             * 2. Removed whenNotPause/whenPaused from pause/unpause (6/14/2018)
                             * 3. Removed whenPaused (6/14/2018)
                             * 4. Switches ownable library to use ZeppelinOS (7/12/18)
                             * 5. Remove constructor (7/13/18)
                             * 6. Reformat, conform to Solidity 0.6 syntax and add error messages (5/13/20)
                             * 7. Make public functions external (5/27/20)
                             */
                            contract Pausable is Ownable {
                                event Pause();
                                event Unpause();
                                event PauserChanged(address indexed newAddress);
                                address public pauser;
                                bool public paused = false;
                                /**
                                 * @dev Modifier to make a function callable only when the contract is not paused.
                                 */
                                modifier whenNotPaused() {
                                    require(!paused, "Pausable: paused");
                                    _;
                                }
                                /**
                                 * @dev throws if called by any account other than the pauser
                                 */
                                modifier onlyPauser() {
                                    require(msg.sender == pauser, "Pausable: caller is not the pauser");
                                    _;
                                }
                                /**
                                 * @dev called by the owner to pause, triggers stopped state
                                 */
                                function pause() external onlyPauser {
                                    paused = true;
                                    emit Pause();
                                }
                                /**
                                 * @dev called by the owner to unpause, returns to normal state
                                 */
                                function unpause() external onlyPauser {
                                    paused = false;
                                    emit Unpause();
                                }
                                /**
                                 * @notice Updates the pauser address.
                                 * @param _newPauser The address of the new pauser.
                                 */
                                function updatePauser(address _newPauser) external onlyOwner {
                                    require(
                                        _newPauser != address(0),
                                        "Pausable: new pauser is the zero address"
                                    );
                                    pauser = _newPauser;
                                    emit PauserChanged(pauser);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: MIT
                             *
                             * Copyright (c) 2018 zOS Global Limited.
                             * Copyright (c) 2018-2020 CENTRE SECZ
                             *
                             * Permission is hereby granted, free of charge, to any person obtaining a copy
                             * of this software and associated documentation files (the "Software"), to deal
                             * in the Software without restriction, including without limitation the rights
                             * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
                             * copies of the Software, and to permit persons to whom the Software is
                             * furnished to do so, subject to the following conditions:
                             *
                             * The above copyright notice and this permission notice shall be included in
                             * copies or substantial portions of the Software.
                             *
                             * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
                             * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
                             * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
                             * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
                             * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
                             * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
                             * SOFTWARE.
                             */
                            pragma solidity 0.6.12;
                            /**
                             * @notice The Ownable contract has an owner address, and provides basic
                             * authorization control functions
                             * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-labs/blob/3887ab77b8adafba4a26ace002f3a684c1a3388b/upgradeability_ownership/contracts/ownership/Ownable.sol
                             * Modifications:
                             * 1. Consolidate OwnableStorage into this contract (7/13/18)
                             * 2. Reformat, conform to Solidity 0.6 syntax, and add error messages (5/13/20)
                             * 3. Make public functions external (5/27/20)
                             */
                            contract Ownable {
                                // Owner of the contract
                                address private _owner;
                                /**
                                 * @dev Event to show ownership has been transferred
                                 * @param previousOwner representing the address of the previous owner
                                 * @param newOwner representing the address of the new owner
                                 */
                                event OwnershipTransferred(address previousOwner, address newOwner);
                                /**
                                 * @dev The constructor sets the original owner of the contract to the sender account.
                                 */
                                constructor() public {
                                    setOwner(msg.sender);
                                }
                                /**
                                 * @dev Tells the address of the owner
                                 * @return the address of the owner
                                 */
                                function owner() external view returns (address) {
                                    return _owner;
                                }
                                /**
                                 * @dev Sets a new owner address
                                 */
                                function setOwner(address newOwner) internal {
                                    _owner = newOwner;
                                }
                                /**
                                 * @dev Throws if called by any account other than the owner.
                                 */
                                modifier onlyOwner() {
                                    require(msg.sender == _owner, "Ownable: caller is not the owner");
                                    _;
                                }
                                /**
                                 * @dev Allows the current owner to transfer control of the contract to a newOwner.
                                 * @param newOwner The address to transfer ownership to.
                                 */
                                function transferOwnership(address newOwner) external onlyOwner {
                                    require(
                                        newOwner != address(0),
                                        "Ownable: new owner is the zero address"
                                    );
                                    emit OwnershipTransferred(_owner, newOwner);
                                    setOwner(newOwner);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
                            import { AbstractFiatTokenV1 } from "./AbstractFiatTokenV1.sol";
                            import { Ownable } from "./Ownable.sol";
                            import { Pausable } from "./Pausable.sol";
                            import { Blacklistable } from "./Blacklistable.sol";
                            /**
                             * @title FiatToken
                             * @dev ERC20 Token backed by fiat reserves
                             */
                            contract FiatTokenV1 is AbstractFiatTokenV1, Ownable, Pausable, Blacklistable {
                                using SafeMath for uint256;
                                string public name;
                                string public symbol;
                                uint8 public decimals;
                                string public currency;
                                address public masterMinter;
                                bool internal initialized;
                                /// @dev A mapping that stores the balance and blacklist states for a given address.
                                /// The first bit defines whether the address is blacklisted (1 if blacklisted, 0 otherwise).
                                /// The last 255 bits define the balance for the address.
                                mapping(address => uint256) internal balanceAndBlacklistStates;
                                mapping(address => mapping(address => uint256)) internal allowed;
                                uint256 internal totalSupply_ = 0;
                                mapping(address => bool) internal minters;
                                mapping(address => uint256) internal minterAllowed;
                                event Mint(address indexed minter, address indexed to, uint256 amount);
                                event Burn(address indexed burner, uint256 amount);
                                event MinterConfigured(address indexed minter, uint256 minterAllowedAmount);
                                event MinterRemoved(address indexed oldMinter);
                                event MasterMinterChanged(address indexed newMasterMinter);
                                /**
                                 * @notice Initializes the fiat token contract.
                                 * @param tokenName       The name of the fiat token.
                                 * @param tokenSymbol     The symbol of the fiat token.
                                 * @param tokenCurrency   The fiat currency that the token represents.
                                 * @param tokenDecimals   The number of decimals that the token uses.
                                 * @param newMasterMinter The masterMinter address for the fiat token.
                                 * @param newPauser       The pauser address for the fiat token.
                                 * @param newBlacklister  The blacklister address for the fiat token.
                                 * @param newOwner        The owner of the fiat token.
                                 */
                                function initialize(
                                    string memory tokenName,
                                    string memory tokenSymbol,
                                    string memory tokenCurrency,
                                    uint8 tokenDecimals,
                                    address newMasterMinter,
                                    address newPauser,
                                    address newBlacklister,
                                    address newOwner
                                ) public {
                                    require(!initialized, "FiatToken: contract is already initialized");
                                    require(
                                        newMasterMinter != address(0),
                                        "FiatToken: new masterMinter is the zero address"
                                    );
                                    require(
                                        newPauser != address(0),
                                        "FiatToken: new pauser is the zero address"
                                    );
                                    require(
                                        newBlacklister != address(0),
                                        "FiatToken: new blacklister is the zero address"
                                    );
                                    require(
                                        newOwner != address(0),
                                        "FiatToken: new owner is the zero address"
                                    );
                                    name = tokenName;
                                    symbol = tokenSymbol;
                                    currency = tokenCurrency;
                                    decimals = tokenDecimals;
                                    masterMinter = newMasterMinter;
                                    pauser = newPauser;
                                    blacklister = newBlacklister;
                                    setOwner(newOwner);
                                    initialized = true;
                                }
                                /**
                                 * @dev Throws if called by any account other than a minter.
                                 */
                                modifier onlyMinters() {
                                    require(minters[msg.sender], "FiatToken: caller is not a minter");
                                    _;
                                }
                                /**
                                 * @notice Mints fiat tokens to an address.
                                 * @param _to The address that will receive the minted tokens.
                                 * @param _amount The amount of tokens to mint. Must be less than or equal
                                 * to the minterAllowance of the caller.
                                 * @return True if the operation was successful.
                                 */
                                function mint(address _to, uint256 _amount)
                                    external
                                    whenNotPaused
                                    onlyMinters
                                    notBlacklisted(msg.sender)
                                    notBlacklisted(_to)
                                    returns (bool)
                                {
                                    require(_to != address(0), "FiatToken: mint to the zero address");
                                    require(_amount > 0, "FiatToken: mint amount not greater than 0");
                                    uint256 mintingAllowedAmount = minterAllowed[msg.sender];
                                    require(
                                        _amount <= mintingAllowedAmount,
                                        "FiatToken: mint amount exceeds minterAllowance"
                                    );
                                    totalSupply_ = totalSupply_.add(_amount);
                                    _setBalance(_to, _balanceOf(_to).add(_amount));
                                    minterAllowed[msg.sender] = mintingAllowedAmount.sub(_amount);
                                    emit Mint(msg.sender, _to, _amount);
                                    emit Transfer(address(0), _to, _amount);
                                    return true;
                                }
                                /**
                                 * @dev Throws if called by any account other than the masterMinter
                                 */
                                modifier onlyMasterMinter() {
                                    require(
                                        msg.sender == masterMinter,
                                        "FiatToken: caller is not the masterMinter"
                                    );
                                    _;
                                }
                                /**
                                 * @notice Gets the minter allowance for an account.
                                 * @param minter The address to check.
                                 * @return The remaining minter allowance for the account.
                                 */
                                function minterAllowance(address minter) external view returns (uint256) {
                                    return minterAllowed[minter];
                                }
                                /**
                                 * @notice Checks if an account is a minter.
                                 * @param account The address to check.
                                 * @return True if the account is a minter, false if the account is not a minter.
                                 */
                                function isMinter(address account) external view returns (bool) {
                                    return minters[account];
                                }
                                /**
                                 * @notice Gets the remaining amount of fiat tokens a spender is allowed to transfer on
                                 * behalf of the token owner.
                                 * @param owner   The token owner's address.
                                 * @param spender The spender's address.
                                 * @return The remaining allowance.
                                 */
                                function allowance(address owner, address spender)
                                    external
                                    override
                                    view
                                    returns (uint256)
                                {
                                    return allowed[owner][spender];
                                }
                                /**
                                 * @notice Gets the totalSupply of the fiat token.
                                 * @return The totalSupply of the fiat token.
                                 */
                                function totalSupply() external override view returns (uint256) {
                                    return totalSupply_;
                                }
                                /**
                                 * @notice Gets the fiat token balance of an account.
                                 * @param account  The address to check.
                                 * @return balance The fiat token balance of the account.
                                 */
                                function balanceOf(address account)
                                    external
                                    override
                                    view
                                    returns (uint256)
                                {
                                    return _balanceOf(account);
                                }
                                /**
                                 * @notice Sets a fiat token allowance for a spender to spend on behalf of the caller.
                                 * @param spender The spender's address.
                                 * @param value   The allowance amount.
                                 * @return True if the operation was successful.
                                 */
                                function approve(address spender, uint256 value)
                                    external
                                    virtual
                                    override
                                    whenNotPaused
                                    notBlacklisted(msg.sender)
                                    notBlacklisted(spender)
                                    returns (bool)
                                {
                                    _approve(msg.sender, spender, value);
                                    return true;
                                }
                                /**
                                 * @dev Internal function to set allowance.
                                 * @param owner     Token owner's address.
                                 * @param spender   Spender's address.
                                 * @param value     Allowance amount.
                                 */
                                function _approve(
                                    address owner,
                                    address spender,
                                    uint256 value
                                ) internal override {
                                    require(owner != address(0), "ERC20: approve from the zero address");
                                    require(spender != address(0), "ERC20: approve to the zero address");
                                    allowed[owner][spender] = value;
                                    emit Approval(owner, spender, value);
                                }
                                /**
                                 * @notice Transfers tokens from an address to another by spending the caller's allowance.
                                 * @dev The caller must have some fiat token allowance on the payer's tokens.
                                 * @param from  Payer's address.
                                 * @param to    Payee's address.
                                 * @param value Transfer amount.
                                 * @return True if the operation was successful.
                                 */
                                function transferFrom(
                                    address from,
                                    address to,
                                    uint256 value
                                )
                                    external
                                    override
                                    whenNotPaused
                                    notBlacklisted(msg.sender)
                                    notBlacklisted(from)
                                    notBlacklisted(to)
                                    returns (bool)
                                {
                                    require(
                                        value <= allowed[from][msg.sender],
                                        "ERC20: transfer amount exceeds allowance"
                                    );
                                    _transfer(from, to, value);
                                    allowed[from][msg.sender] = allowed[from][msg.sender].sub(value);
                                    return true;
                                }
                                /**
                                 * @notice Transfers tokens from the caller.
                                 * @param to    Payee's address.
                                 * @param value Transfer amount.
                                 * @return True if the operation was successful.
                                 */
                                function transfer(address to, uint256 value)
                                    external
                                    override
                                    whenNotPaused
                                    notBlacklisted(msg.sender)
                                    notBlacklisted(to)
                                    returns (bool)
                                {
                                    _transfer(msg.sender, to, value);
                                    return true;
                                }
                                /**
                                 * @dev Internal function to process transfers.
                                 * @param from  Payer's address.
                                 * @param to    Payee's address.
                                 * @param value Transfer amount.
                                 */
                                function _transfer(
                                    address from,
                                    address to,
                                    uint256 value
                                ) internal override {
                                    require(from != address(0), "ERC20: transfer from the zero address");
                                    require(to != address(0), "ERC20: transfer to the zero address");
                                    require(
                                        value <= _balanceOf(from),
                                        "ERC20: transfer amount exceeds balance"
                                    );
                                    _setBalance(from, _balanceOf(from).sub(value));
                                    _setBalance(to, _balanceOf(to).add(value));
                                    emit Transfer(from, to, value);
                                }
                                /**
                                 * @notice Adds or updates a new minter with a mint allowance.
                                 * @param minter The address of the minter.
                                 * @param minterAllowedAmount The minting amount allowed for the minter.
                                 * @return True if the operation was successful.
                                 */
                                function configureMinter(address minter, uint256 minterAllowedAmount)
                                    external
                                    whenNotPaused
                                    onlyMasterMinter
                                    returns (bool)
                                {
                                    minters[minter] = true;
                                    minterAllowed[minter] = minterAllowedAmount;
                                    emit MinterConfigured(minter, minterAllowedAmount);
                                    return true;
                                }
                                /**
                                 * @notice Removes a minter.
                                 * @param minter The address of the minter to remove.
                                 * @return True if the operation was successful.
                                 */
                                function removeMinter(address minter)
                                    external
                                    onlyMasterMinter
                                    returns (bool)
                                {
                                    minters[minter] = false;
                                    minterAllowed[minter] = 0;
                                    emit MinterRemoved(minter);
                                    return true;
                                }
                                /**
                                 * @notice Allows a minter to burn some of its own tokens.
                                 * @dev The caller must be a minter, must not be blacklisted, and the amount to burn
                                 * should be less than or equal to the account's balance.
                                 * @param _amount the amount of tokens to be burned.
                                 */
                                function burn(uint256 _amount)
                                    external
                                    whenNotPaused
                                    onlyMinters
                                    notBlacklisted(msg.sender)
                                {
                                    uint256 balance = _balanceOf(msg.sender);
                                    require(_amount > 0, "FiatToken: burn amount not greater than 0");
                                    require(balance >= _amount, "FiatToken: burn amount exceeds balance");
                                    totalSupply_ = totalSupply_.sub(_amount);
                                    _setBalance(msg.sender, balance.sub(_amount));
                                    emit Burn(msg.sender, _amount);
                                    emit Transfer(msg.sender, address(0), _amount);
                                }
                                /**
                                 * @notice Updates the master minter address.
                                 * @param _newMasterMinter The address of the new master minter.
                                 */
                                function updateMasterMinter(address _newMasterMinter) external onlyOwner {
                                    require(
                                        _newMasterMinter != address(0),
                                        "FiatToken: new masterMinter is the zero address"
                                    );
                                    masterMinter = _newMasterMinter;
                                    emit MasterMinterChanged(masterMinter);
                                }
                                /**
                                 * @inheritdoc Blacklistable
                                 */
                                function _blacklist(address _account) internal override {
                                    _setBlacklistState(_account, true);
                                }
                                /**
                                 * @inheritdoc Blacklistable
                                 */
                                function _unBlacklist(address _account) internal override {
                                    _setBlacklistState(_account, false);
                                }
                                /**
                                 * @dev Helper method that sets the blacklist state of an account.
                                 * @param _account         The address of the account.
                                 * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
                                 */
                                function _setBlacklistState(address _account, bool _shouldBlacklist)
                                    internal
                                    virtual
                                {
                                    _deprecatedBlacklisted[_account] = _shouldBlacklist;
                                }
                                /**
                                 * @dev Helper method that sets the balance of an account.
                                 * @param _account The address of the account.
                                 * @param _balance The new fiat token balance of the account.
                                 */
                                function _setBalance(address _account, uint256 _balance) internal virtual {
                                    balanceAndBlacklistStates[_account] = _balance;
                                }
                                /**
                                 * @inheritdoc Blacklistable
                                 */
                                function _isBlacklisted(address _account)
                                    internal
                                    virtual
                                    override
                                    view
                                    returns (bool)
                                {
                                    return _deprecatedBlacklisted[_account];
                                }
                                /**
                                 * @dev Helper method to obtain the balance of an account.
                                 * @param _account  The address of the account.
                                 * @return          The fiat token balance of the account.
                                 */
                                function _balanceOf(address _account)
                                    internal
                                    virtual
                                    view
                                    returns (uint256)
                                {
                                    return balanceAndBlacklistStates[_account];
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { Ownable } from "./Ownable.sol";
                            /**
                             * @title Blacklistable Token
                             * @dev Allows accounts to be blacklisted by a "blacklister" role
                             */
                            abstract contract Blacklistable is Ownable {
                                address public blacklister;
                                mapping(address => bool) internal _deprecatedBlacklisted;
                                event Blacklisted(address indexed _account);
                                event UnBlacklisted(address indexed _account);
                                event BlacklisterChanged(address indexed newBlacklister);
                                /**
                                 * @dev Throws if called by any account other than the blacklister.
                                 */
                                modifier onlyBlacklister() {
                                    require(
                                        msg.sender == blacklister,
                                        "Blacklistable: caller is not the blacklister"
                                    );
                                    _;
                                }
                                /**
                                 * @dev Throws if argument account is blacklisted.
                                 * @param _account The address to check.
                                 */
                                modifier notBlacklisted(address _account) {
                                    require(
                                        !_isBlacklisted(_account),
                                        "Blacklistable: account is blacklisted"
                                    );
                                    _;
                                }
                                /**
                                 * @notice Checks if account is blacklisted.
                                 * @param _account The address to check.
                                 * @return True if the account is blacklisted, false if the account is not blacklisted.
                                 */
                                function isBlacklisted(address _account) external view returns (bool) {
                                    return _isBlacklisted(_account);
                                }
                                /**
                                 * @notice Adds account to blacklist.
                                 * @param _account The address to blacklist.
                                 */
                                function blacklist(address _account) external onlyBlacklister {
                                    _blacklist(_account);
                                    emit Blacklisted(_account);
                                }
                                /**
                                 * @notice Removes account from blacklist.
                                 * @param _account The address to remove from the blacklist.
                                 */
                                function unBlacklist(address _account) external onlyBlacklister {
                                    _unBlacklist(_account);
                                    emit UnBlacklisted(_account);
                                }
                                /**
                                 * @notice Updates the blacklister address.
                                 * @param _newBlacklister The address of the new blacklister.
                                 */
                                function updateBlacklister(address _newBlacklister) external onlyOwner {
                                    require(
                                        _newBlacklister != address(0),
                                        "Blacklistable: new blacklister is the zero address"
                                    );
                                    blacklister = _newBlacklister;
                                    emit BlacklisterChanged(blacklister);
                                }
                                /**
                                 * @dev Checks if account is blacklisted.
                                 * @param _account The address to check.
                                 * @return true if the account is blacklisted, false otherwise.
                                 */
                                function _isBlacklisted(address _account)
                                    internal
                                    virtual
                                    view
                                    returns (bool);
                                /**
                                 * @dev Helper method that blacklists an account.
                                 * @param _account The address to blacklist.
                                 */
                                function _blacklist(address _account) internal virtual;
                                /**
                                 * @dev Helper method that unblacklists an account.
                                 * @param _account The address to unblacklist.
                                 */
                                function _unBlacklist(address _account) internal virtual;
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                            abstract contract AbstractFiatTokenV1 is IERC20 {
                                function _approve(
                                    address owner,
                                    address spender,
                                    uint256 value
                                ) internal virtual;
                                function _transfer(
                                    address from,
                                    address to,
                                    uint256 value
                                ) internal virtual;
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { Ownable } from "../v1/Ownable.sol";
                            import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                            import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
                            contract Rescuable is Ownable {
                                using SafeERC20 for IERC20;
                                address private _rescuer;
                                event RescuerChanged(address indexed newRescuer);
                                /**
                                 * @notice Returns current rescuer
                                 * @return Rescuer's address
                                 */
                                function rescuer() external view returns (address) {
                                    return _rescuer;
                                }
                                /**
                                 * @notice Revert if called by any account other than the rescuer.
                                 */
                                modifier onlyRescuer() {
                                    require(msg.sender == _rescuer, "Rescuable: caller is not the rescuer");
                                    _;
                                }
                                /**
                                 * @notice Rescue ERC20 tokens locked up in this contract.
                                 * @param tokenContract ERC20 token contract address
                                 * @param to        Recipient address
                                 * @param amount    Amount to withdraw
                                 */
                                function rescueERC20(
                                    IERC20 tokenContract,
                                    address to,
                                    uint256 amount
                                ) external onlyRescuer {
                                    tokenContract.safeTransfer(to, amount);
                                }
                                /**
                                 * @notice Updates the rescuer address.
                                 * @param newRescuer The address of the new rescuer.
                                 */
                                function updateRescuer(address newRescuer) external onlyOwner {
                                    require(
                                        newRescuer != address(0),
                                        "Rescuable: new rescuer is the zero address"
                                    );
                                    _rescuer = newRescuer;
                                    emit RescuerChanged(newRescuer);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { FiatTokenV1 } from "../v1/FiatTokenV1.sol";
                            import { Rescuable } from "./Rescuable.sol";
                            /**
                             * @title FiatTokenV1_1
                             * @dev ERC20 Token backed by fiat reserves
                             */
                            contract FiatTokenV1_1 is FiatTokenV1, Rescuable {
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            import { ECRecover } from "./ECRecover.sol";
                            import { IERC1271 } from "../interface/IERC1271.sol";
                            /**
                             * @dev Signature verification helper that can be used instead of `ECRecover.recover` to seamlessly support both ECDSA
                             * signatures from externally owned accounts (EOAs) as well as ERC1271 signatures from smart contract wallets.
                             *
                             * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/SignatureChecker.sol
                             */
                            library SignatureChecker {
                                /**
                                 * @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
                                 * signature is validated against that smart contract using ERC1271, otherwise it's validated using `ECRecover.recover`.
                                 * @param signer        Address of the claimed signer
                                 * @param digest        Keccak-256 hash digest of the signed message
                                 * @param signature     Signature byte array associated with hash
                                 */
                                function isValidSignatureNow(
                                    address signer,
                                    bytes32 digest,
                                    bytes memory signature
                                ) external view returns (bool) {
                                    if (!isContract(signer)) {
                                        return ECRecover.recover(digest, signature) == signer;
                                    }
                                    return isValidERC1271SignatureNow(signer, digest, signature);
                                }
                                /**
                                 * @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
                                 * against the signer smart contract using ERC1271.
                                 * @param signer        Address of the claimed signer
                                 * @param digest        Keccak-256 hash digest of the signed message
                                 * @param signature     Signature byte array associated with hash
                                 *
                                 * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
                                 * change through time. It could return true at block N and false at block N+1 (or the opposite).
                                 */
                                function isValidERC1271SignatureNow(
                                    address signer,
                                    bytes32 digest,
                                    bytes memory signature
                                ) internal view returns (bool) {
                                    (bool success, bytes memory result) = signer.staticcall(
                                        abi.encodeWithSelector(
                                            IERC1271.isValidSignature.selector,
                                            digest,
                                            signature
                                        )
                                    );
                                    return (success &&
                                        result.length >= 32 &&
                                        abi.decode(result, (bytes32)) ==
                                        bytes32(IERC1271.isValidSignature.selector));
                                }
                                /**
                                 * @dev Checks if the input address is a smart contract.
                                 */
                                function isContract(address addr) internal view returns (bool) {
                                    uint256 size;
                                    assembly {
                                        size := extcodesize(addr)
                                    }
                                    return size > 0;
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            /**
                             * @dev Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing.
                             *
                             * The library provides methods for generating a hash of a message that conforms to the
                             * https://eips.ethereum.org/EIPS/eip-191[EIP 191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712]
                             * specifications.
                             */
                            library MessageHashUtils {
                                /**
                                 * @dev Returns the keccak256 digest of an EIP-712 typed data (EIP-191 version `0x01`).
                                 * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/MessageHashUtils.sol
                                 *
                                 * The digest is calculated from a `domainSeparator` and a `structHash`, by prefixing them with
                                 * `\\x19\\x01` and hashing the result. It corresponds to the hash signed by the
                                 * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] JSON-RPC method as part of EIP-712.
                                 *
                                 * @param domainSeparator    Domain separator
                                 * @param structHash         Hashed EIP-712 data struct
                                 * @return digest            The keccak256 digest of an EIP-712 typed data
                                 */
                                function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash)
                                    internal
                                    pure
                                    returns (bytes32 digest)
                                {
                                    assembly {
                                        let ptr := mload(0x40)
                                        mstore(ptr, "\\x19\\x01")
                                        mstore(add(ptr, 0x02), domainSeparator)
                                        mstore(add(ptr, 0x22), structHash)
                                        digest := keccak256(ptr, 0x42)
                                    }
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            /**
                             * @title EIP712
                             * @notice A library that provides EIP712 helper functions
                             */
                            library EIP712 {
                                /**
                                 * @notice Make EIP712 domain separator
                                 * @param name      Contract name
                                 * @param version   Contract version
                                 * @param chainId   Blockchain ID
                                 * @return Domain separator
                                 */
                                function makeDomainSeparator(
                                    string memory name,
                                    string memory version,
                                    uint256 chainId
                                ) internal view returns (bytes32) {
                                    return
                                        keccak256(
                                            abi.encode(
                                                // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                                                0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                                                keccak256(bytes(name)),
                                                keccak256(bytes(version)),
                                                chainId,
                                                address(this)
                                            )
                                        );
                                }
                                /**
                                 * @notice Make EIP712 domain separator
                                 * @param name      Contract name
                                 * @param version   Contract version
                                 * @return Domain separator
                                 */
                                function makeDomainSeparator(string memory name, string memory version)
                                    internal
                                    view
                                    returns (bytes32)
                                {
                                    uint256 chainId;
                                    assembly {
                                        chainId := chainid()
                                    }
                                    return makeDomainSeparator(name, version, chainId);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            /**
                             * @title ECRecover
                             * @notice A library that provides a safe ECDSA recovery function
                             */
                            library ECRecover {
                                /**
                                 * @notice Recover signer's address from a signed message
                                 * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/65e4ffde586ec89af3b7e9140bdc9235d1254853/contracts/cryptography/ECDSA.sol
                                 * Modifications: Accept v, r, and s as separate arguments
                                 * @param digest    Keccak-256 hash digest of the signed message
                                 * @param v         v of the signature
                                 * @param r         r of the signature
                                 * @param s         s of the signature
                                 * @return Signer address
                                 */
                                function recover(
                                    bytes32 digest,
                                    uint8 v,
                                    bytes32 r,
                                    bytes32 s
                                ) internal pure returns (address) {
                                    // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                                    // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                                    // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
                                    // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                                    //
                                    // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                                    // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                                    // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                                    // these malleable signatures as well.
                                    if (
                                        uint256(s) >
                                        0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0
                                    ) {
                                        revert("ECRecover: invalid signature 's' value");
                                    }
                                    if (v != 27 && v != 28) {
                                        revert("ECRecover: invalid signature 'v' value");
                                    }
                                    // If the signature is valid (and not malleable), return the signer address
                                    address signer = ecrecover(digest, v, r, s);
                                    require(signer != address(0), "ECRecover: invalid signature");
                                    return signer;
                                }
                                /**
                                 * @notice Recover signer's address from a signed message
                                 * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/0053ee040a7ff1dbc39691c9e67a69f564930a88/contracts/utils/cryptography/ECDSA.sol
                                 * @param digest    Keccak-256 hash digest of the signed message
                                 * @param signature Signature byte array associated with hash
                                 * @return Signer address
                                 */
                                function recover(bytes32 digest, bytes memory signature)
                                    internal
                                    pure
                                    returns (address)
                                {
                                    require(signature.length == 65, "ECRecover: invalid signature length");
                                    bytes32 r;
                                    bytes32 s;
                                    uint8 v;
                                    // ecrecover takes the signature parameters, and the only way to get them
                                    // currently is to use assembly.
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        r := mload(add(signature, 0x20))
                                        s := mload(add(signature, 0x40))
                                        v := byte(0, mload(add(signature, 0x60)))
                                    }
                                    return recover(digest, v, r, s);
                                }
                            }
                            /**
                             * SPDX-License-Identifier: Apache-2.0
                             *
                             * Copyright (c) 2023, Circle Internet Financial, LLC.
                             *
                             * Licensed under the Apache License, Version 2.0 (the "License");
                             * you may not use this file except in compliance with the License.
                             * You may obtain a copy of the License at
                             *
                             * http://www.apache.org/licenses/LICENSE-2.0
                             *
                             * Unless required by applicable law or agreed to in writing, software
                             * distributed under the License is distributed on an "AS IS" BASIS,
                             * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                             * See the License for the specific language governing permissions and
                             * limitations under the License.
                             */
                            pragma solidity 0.6.12;
                            /**
                             * @dev Interface of the ERC1271 standard signature validation method for
                             * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
                             */
                            interface IERC1271 {
                                /**
                                 * @dev Should return whether the signature provided is valid for the provided data
                                 * @param hash          Hash of the data to be signed
                                 * @param signature     Signature byte array associated with the provided data hash
                                 * @return magicValue   bytes4 magic value 0x1626ba7e when function passes
                                 */
                                function isValidSignature(bytes32 hash, bytes memory signature)
                                    external
                                    view
                                    returns (bytes4 magicValue);
                            }
                            

                            File 7 of 10: Endpoint
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity 0.7.6;
                            import "./interfaces/ILayerZeroReceiver.sol";
                            import "./interfaces/ILayerZeroEndpoint.sol";
                            import "./interfaces/ILayerZeroMessagingLibrary.sol";
                            import "@openzeppelin/contracts/access/Ownable.sol";
                            contract Endpoint is Ownable, ILayerZeroEndpoint {
                                uint16 public immutable chainId;
                                // installed libraries and reserved versions
                                uint16 public constant BLOCK_VERSION = 65535;
                                uint16 public constant DEFAULT_VERSION = 0;
                                uint16 public latestVersion;
                                mapping(uint16 => ILayerZeroMessagingLibrary) public libraryLookup; // version -> ILayerZeroEndpointLibrary
                                // default send/receive libraries
                                uint16 public defaultSendVersion;
                                uint16 public defaultReceiveVersion;
                                ILayerZeroMessagingLibrary public defaultSendLibrary;
                                address public defaultReceiveLibraryAddress;
                                struct LibraryConfig {
                                    uint16 sendVersion;
                                    uint16 receiveVersion;
                                    address receiveLibraryAddress;
                                    ILayerZeroMessagingLibrary sendLibrary;
                                }
                                struct StoredPayload {
                                    uint64 payloadLength;
                                    address dstAddress;
                                    bytes32 payloadHash;
                                }
                                // user app config = [uaAddress]
                                mapping(address => LibraryConfig) public uaConfigLookup;
                                // inboundNonce = [srcChainId][srcAddress].
                                mapping(uint16 => mapping(bytes => uint64)) public inboundNonce;
                                // outboundNonce = [dstChainId][srcAddress].
                                mapping(uint16 => mapping(address => uint64)) public outboundNonce;
                                // storedPayload = [srcChainId][srcAddress]
                                mapping(uint16 => mapping(bytes => StoredPayload)) public storedPayload;
                                // library versioning events
                                event NewLibraryVersionAdded(uint16 version);
                                event DefaultSendVersionSet(uint16 version);
                                event DefaultReceiveVersionSet(uint16 version);
                                event UaSendVersionSet(address ua, uint16 version);
                                event UaReceiveVersionSet(address ua, uint16 version);
                                event UaForceResumeReceive(uint16 chainId, bytes srcAddress);
                                // payload events
                                event PayloadCleared(uint16 srcChainId, bytes srcAddress, uint64 nonce, address dstAddress);
                                event PayloadStored(uint16 srcChainId, bytes srcAddress, address dstAddress, uint64 nonce, bytes payload, bytes reason);
                                constructor(uint16 _chainId) {
                                    chainId = _chainId;
                                }
                                //---------------------------------------------------------------------------
                                // send and receive nonreentrant lock
                                uint8 internal constant _NOT_ENTERED = 1;
                                uint8 internal constant _ENTERED = 2;
                                uint8 internal _send_entered_state = 1;
                                uint8 internal _receive_entered_state = 1;
                                modifier sendNonReentrant() {
                                    require(_send_entered_state == _NOT_ENTERED, "LayerZero: no send reentrancy");
                                    _send_entered_state = _ENTERED;
                                    _;
                                    _send_entered_state = _NOT_ENTERED;
                                }
                                modifier receiveNonReentrant() {
                                    require(_receive_entered_state == _NOT_ENTERED, "LayerZero: no receive reentrancy");
                                    _receive_entered_state = _ENTERED;
                                    _;
                                    _receive_entered_state = _NOT_ENTERED;
                                }
                                // BLOCK_VERSION is also a valid version
                                modifier validVersion(uint16 _version) {
                                    require(_version <= latestVersion || _version == BLOCK_VERSION, "LayerZero: invalid messaging library version");
                                    _;
                                }
                                //---------------------------------------------------------------------------
                                // User Application Calls - Endpoint Interface
                                function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable override sendNonReentrant {
                                    LibraryConfig storage uaConfig = uaConfigLookup[msg.sender];
                                    uint64 nonce = ++outboundNonce[_dstChainId][msg.sender];
                                    _getSendLibrary(uaConfig).send{value: msg.value}(msg.sender, nonce, _dstChainId, _destination, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
                                }
                                //---------------------------------------------------------------------------
                                // authenticated Library (msg.sender) Calls to pass through Endpoint to UA (dstAddress)
                                function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external override receiveNonReentrant {
                                    // assert and increment the nonce. no message shuffling
                                    require(_nonce == ++inboundNonce[_srcChainId][_srcAddress], "LayerZero: wrong nonce");
                                    LibraryConfig storage uaConfig = uaConfigLookup[_dstAddress];
                                    // authentication to prevent cross-version message validation
                                    // protects against a malicious library from passing arbitrary data
                                    if (uaConfig.receiveVersion == DEFAULT_VERSION) {
                                        require(defaultReceiveLibraryAddress == msg.sender, "LayerZero: invalid default library");
                                    } else {
                                        require(uaConfig.receiveLibraryAddress == msg.sender, "LayerZero: invalid library");
                                    }
                                    // block if any message blocking
                                    StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                    require(sp.payloadHash == bytes32(0), "LayerZero: in message blocking");
                                    try ILayerZeroReceiver(_dstAddress).lzReceive{gas: _gasLimit}(_srcChainId, _srcAddress, _nonce, _payload) {
                                        // success, do nothing, end of the message delivery
                                    } catch (bytes memory reason) {
                                        // revert nonce if any uncaught errors/exceptions if the ua chooses the blocking mode
                                        storedPayload[_srcChainId][_srcAddress] = StoredPayload(uint64(_payload.length), _dstAddress, keccak256(_payload));
                                        emit PayloadStored(_srcChainId, _srcAddress, _dstAddress, _nonce, _payload, reason);
                                    }
                                }
                                function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external override receiveNonReentrant {
                                    StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                    require(sp.payloadHash != bytes32(0), "LayerZero: no stored payload");
                                    require(_payload.length == sp.payloadLength && keccak256(_payload) == sp.payloadHash, "LayerZero: invalid payload");
                                    address dstAddress = sp.dstAddress;
                                    // empty the storedPayload
                                    sp.payloadLength = 0;
                                    sp.dstAddress = address(0);
                                    sp.payloadHash = bytes32(0);
                                    uint64 nonce = inboundNonce[_srcChainId][_srcAddress];
                                    ILayerZeroReceiver(dstAddress).lzReceive(_srcChainId, _srcAddress, nonce, _payload);
                                    emit PayloadCleared(_srcChainId, _srcAddress, nonce, dstAddress);
                                }
                                //---------------------------------------------------------------------------
                                // Owner Calls, only new library version upgrade (3 steps)
                                // note libraryLookup[0] = 0x0, no library implementation
                                // LIBRARY UPGRADE step 1: set _newLayerZeroLibraryAddress be the new version
                                function newVersion(address _newLayerZeroLibraryAddress) external onlyOwner {
                                    require(_newLayerZeroLibraryAddress != address(0x0), "LayerZero: new version cannot be zero address");
                                    require(latestVersion < 65535, "LayerZero: can not add new messaging library");
                                    latestVersion++;
                                    libraryLookup[latestVersion] = ILayerZeroMessagingLibrary(_newLayerZeroLibraryAddress);
                                    emit NewLibraryVersionAdded(latestVersion);
                                }
                                // LIBRARY UPGRADE step 2: stop sending messages from the old version
                                function setDefaultSendVersion(uint16 _newDefaultSendVersion) external onlyOwner validVersion(_newDefaultSendVersion) {
                                    require(_newDefaultSendVersion != DEFAULT_VERSION, "LayerZero: default send version must > 0");
                                    defaultSendVersion = _newDefaultSendVersion;
                                    defaultSendLibrary = libraryLookup[defaultSendVersion];
                                    emit DefaultSendVersionSet(_newDefaultSendVersion);
                                }
                                // LIBRARY UPGRADE step 3: stop receiving messages from the old version
                                function setDefaultReceiveVersion(uint16 _newDefaultReceiveVersion) external onlyOwner validVersion(_newDefaultReceiveVersion) {
                                    require(_newDefaultReceiveVersion != DEFAULT_VERSION, "LayerZero: default receive version must > 0");
                                    defaultReceiveVersion = _newDefaultReceiveVersion;
                                    defaultReceiveLibraryAddress = address(libraryLookup[defaultReceiveVersion]);
                                    emit DefaultReceiveVersionSet(_newDefaultReceiveVersion);
                                }
                                //---------------------------------------------------------------------------
                                // User Application Calls - UA set/get Interface
                                function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external override validVersion(_version) {
                                    if (_version == DEFAULT_VERSION) {
                                        require(defaultSendVersion == defaultReceiveVersion, "LayerZero: can not set Config during DEFAULT migration");
                                        _version = defaultSendVersion;
                                    }
                                    require(_version != BLOCK_VERSION, "LayerZero: can not set config for BLOCK_VERSION");
                                    libraryLookup[_version].setConfig(_chainId, msg.sender, _configType, _config);
                                }
                                // Migration step 1: set the send version
                                // Define what library the UA points too
                                function setSendVersion(uint16 _newVersion) external override validVersion(_newVersion) {
                                    // write into config
                                    LibraryConfig storage uaConfig = uaConfigLookup[msg.sender];
                                    uaConfig.sendVersion = _newVersion;
                                    // the libraryLookup[BLOCK_VERSION || DEFAULT_VERSION] = 0x0
                                    uaConfig.sendLibrary = libraryLookup[_newVersion];
                                    emit UaSendVersionSet(msg.sender, _newVersion);
                                }
                                // Migration step 2: set the receive version
                                // after all messages sent from the old version are received
                                // the UA can now safely switch to the new receive version
                                // it is the UA's responsibility make sure all messages from the old version are processed
                                function setReceiveVersion(uint16 _newVersion) external override validVersion(_newVersion) {
                                    // write into config
                                    LibraryConfig storage uaConfig = uaConfigLookup[msg.sender];
                                    uaConfig.receiveVersion = _newVersion;
                                    // the libraryLookup[BLOCK_VERSION || DEFAULT_VERSION] = 0x0
                                    uaConfig.receiveLibraryAddress = address(libraryLookup[_newVersion]);
                                    emit UaReceiveVersionSet(msg.sender, _newVersion);
                                }
                                function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override {
                                    StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                    // revert if no messages are cached. safeguard malicious UA behaviour
                                    require(sp.payloadHash != bytes32(0), "LayerZero: no stored payload");
                                    require(sp.dstAddress == msg.sender, "LayerZero: invalid caller");
                                    // empty the storedPayload
                                    sp.payloadLength = 0;
                                    sp.dstAddress = address(0);
                                    sp.payloadHash = bytes32(0);
                                    // emit the event with the new nonce
                                    emit UaForceResumeReceive(_srcChainId, _srcAddress);
                                }
                                //---------------------------------------------------------------------------
                                // view helper function
                                function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParams) external view override returns (uint nativeFee, uint zroFee) {
                                    LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                    ILayerZeroMessagingLibrary lib = uaConfig.sendVersion == DEFAULT_VERSION ? defaultSendLibrary : uaConfig.sendLibrary;
                                    return lib.estimateFees(_dstChainId, _userApplication, _payload, _payInZRO, _adapterParams);
                                }
                                function _getSendLibrary(LibraryConfig storage uaConfig) internal view returns (ILayerZeroMessagingLibrary) {
                                    if (uaConfig.sendVersion == DEFAULT_VERSION) {
                                        // check if the in send-blocking upgrade
                                        require(defaultSendVersion != BLOCK_VERSION, "LayerZero: default in BLOCK_VERSION");
                                        return defaultSendLibrary;
                                    } else {
                                        // check if the in send-blocking upgrade
                                        require(uaConfig.sendVersion != BLOCK_VERSION, "LayerZero: in BLOCK_VERSION");
                                        return uaConfig.sendLibrary;
                                    }
                                }
                                function getSendLibraryAddress(address _userApplication) external view override returns (address sendLibraryAddress) {
                                    LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                    uint16 sendVersion = uaConfig.sendVersion;
                                    require(sendVersion != BLOCK_VERSION, "LayerZero: send version is BLOCK_VERSION");
                                    if (sendVersion == DEFAULT_VERSION) {
                                        require(defaultSendVersion != BLOCK_VERSION, "LayerZero: send version (default) is BLOCK_VERSION");
                                        sendLibraryAddress = address(defaultSendLibrary);
                                    } else {
                                        sendLibraryAddress = address(uaConfig.sendLibrary);
                                    }
                                }
                                function getReceiveLibraryAddress(address _userApplication) external view override returns (address receiveLibraryAddress) {
                                    LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                    uint16 receiveVersion = uaConfig.receiveVersion;
                                    require(receiveVersion != BLOCK_VERSION, "LayerZero: receive version is BLOCK_VERSION");
                                    if (receiveVersion == DEFAULT_VERSION) {
                                        require(defaultReceiveVersion != BLOCK_VERSION, "LayerZero: receive version (default) is BLOCK_VERSION");
                                        receiveLibraryAddress = defaultReceiveLibraryAddress;
                                    } else {
                                        receiveLibraryAddress = uaConfig.receiveLibraryAddress;
                                    }
                                }
                                function isSendingPayload() external view override returns (bool) {
                                    return _send_entered_state == _ENTERED;
                                }
                                function isReceivingPayload() external view override returns (bool) {
                                    return _receive_entered_state == _ENTERED;
                                }
                                function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view override returns (uint64) {
                                    return inboundNonce[_srcChainId][_srcAddress];
                                }
                                function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view override returns (uint64) {
                                    return outboundNonce[_dstChainId][_srcAddress];
                                }
                                function getChainId() external view override returns (uint16) {
                                    return chainId;
                                }
                                function getSendVersion(address _userApplication) external view override returns (uint16) {
                                    LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                    return uaConfig.sendVersion == DEFAULT_VERSION ? defaultSendVersion : uaConfig.sendVersion;
                                }
                                function getReceiveVersion(address _userApplication) external view override returns (uint16) {
                                    LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                    return uaConfig.receiveVersion == DEFAULT_VERSION ? defaultReceiveVersion : uaConfig.receiveVersion;
                                }
                                function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view override validVersion(_version) returns (bytes memory) {
                                    if (_version == DEFAULT_VERSION) {
                                        require(defaultSendVersion == defaultReceiveVersion, "LayerZero: no DEFAULT config while migration");
                                        _version = defaultSendVersion;
                                    }
                                    require(_version != BLOCK_VERSION, "LayerZero: can not get config for BLOCK_VERSION");
                                    return libraryLookup[_version].getConfig(_chainId, _userApplication, _configType);
                                }
                                function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view override returns (bool) {
                                    StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                    return sp.payloadHash != bytes32(0);
                                }
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.5.0;
                            interface ILayerZeroReceiver {
                                // @notice LayerZero endpoint will invoke this function to deliver the message on the destination
                                // @param _srcChainId - the source endpoint identifier
                                // @param _srcAddress - the source sending contract address from the source chain
                                // @param _nonce - the ordered message nonce
                                // @param _payload - the signed payload is the UA bytes has encoded to be sent
                                function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.5.0;
                            import "./ILayerZeroUserApplicationConfig.sol";
                            interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
                                // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
                                // @param _dstChainId - the destination chain identifier
                                // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
                                // @param _payload - a custom bytes payload to send to the destination contract
                                // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
                                // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
                                // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
                                function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                                // @notice used by the messaging library to publish verified payload
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source contract (as bytes) at the source chain
                                // @param _dstAddress - the address on destination chain
                                // @param _nonce - the unbound message ordering nonce
                                // @param _gasLimit - the gas limit for external contract execution
                                // @param _payload - verified payload to send to the destination contract
                                function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
                                // @notice get the inboundNonce of a receiver from a source chain which could be EVM or non-EVM chain
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
                                // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
                                // @param _srcAddress - the source chain contract address
                                function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
                                // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
                                // @param _dstChainId - the destination chain identifier
                                // @param _userApplication - the user app address on this EVM chain
                                // @param _payload - the custom message to send over LayerZero
                                // @param _payInZRO - if false, user app pays the protocol fee in native token
                                // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
                                function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                                // @notice get this Endpoint's immutable source identifier
                                function getChainId() external view returns (uint16);
                                // @notice the interface to retry failed message on this Endpoint destination
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                // @param _payload - the payload to be retried
                                function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
                                // @notice query if any STORED payload (message blocking) at the endpoint.
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
                                // @notice query if the _libraryAddress is valid for sending msgs.
                                // @param _userApplication - the user app address on this EVM chain
                                function getSendLibraryAddress(address _userApplication) external view returns (address);
                                // @notice query if the _libraryAddress is valid for receiving msgs.
                                // @param _userApplication - the user app address on this EVM chain
                                function getReceiveLibraryAddress(address _userApplication) external view returns (address);
                                // @notice query if the non-reentrancy guard for send() is on
                                // @return true if the guard is on. false otherwise
                                function isSendingPayload() external view returns (bool);
                                // @notice query if the non-reentrancy guard for receive() is on
                                // @return true if the guard is on. false otherwise
                                function isReceivingPayload() external view returns (bool);
                                // @notice get the configuration of the LayerZero messaging library of the specified version
                                // @param _version - messaging library version
                                // @param _chainId - the chainId for the pending config change
                                // @param _userApplication - the contract address of the user application
                                // @param _configType - type of configuration. every messaging library has its own convention.
                                function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                                // @notice get the send() LayerZero messaging library version
                                // @param _userApplication - the contract address of the user application
                                function getSendVersion(address _userApplication) external view returns (uint16);
                                // @notice get the lzReceive() LayerZero messaging library version
                                // @param _userApplication - the contract address of the user application
                                function getReceiveVersion(address _userApplication) external view returns (uint16);
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.7.0;
                            import "./ILayerZeroUserApplicationConfig.sol";
                            interface ILayerZeroMessagingLibrary {
                                // send(), messages will be inflight.
                                function send(address _userApplication, uint64 _lastNonce, uint16 _chainId, bytes calldata _destination, bytes calldata _payload, address payable refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                                // estimate native fee at the send side
                                function estimateFees(uint16 _chainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                                //---------------------------------------------------------------------------
                                // setConfig / getConfig are User Application (UA) functions to specify Oracle, Relayer, blockConfirmations, libraryVersion
                                function setConfig(uint16 _chainId, address _userApplication, uint _configType, bytes calldata _config) external;
                                function getConfig(uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            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 () {
                                    address msgSender = _msgSender();
                                    _owner = msgSender;
                                    emit OwnershipTransferred(address(0), msgSender);
                                }
                                /**
                                 * @dev Returns the address of the current owner.
                                 */
                                function owner() public view virtual returns (address) {
                                    return _owner;
                                }
                                /**
                                 * @dev Throws if called by any account other than the owner.
                                 */
                                modifier onlyOwner() {
                                    require(owner() == _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 {
                                    emit OwnershipTransferred(_owner, address(0));
                                    _owner = address(0);
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                                 * Can only be called by the current owner.
                                 */
                                function transferOwnership(address newOwner) public virtual onlyOwner {
                                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                                    emit OwnershipTransferred(_owner, newOwner);
                                    _owner = newOwner;
                                }
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.5.0;
                            interface ILayerZeroUserApplicationConfig {
                                // @notice set the configuration of the LayerZero messaging library of the specified version
                                // @param _version - messaging library version
                                // @param _chainId - the chainId for the pending config change
                                // @param _configType - type of configuration. every messaging library has its own convention.
                                // @param _config - configuration in the bytes. can encode arbitrary content.
                                function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
                                // @notice set the send() LayerZero messaging library version to _version
                                // @param _version - new messaging library version
                                function setSendVersion(uint16 _version) external;
                                // @notice set the lzReceive() LayerZero messaging library version to _version
                                // @param _version - new messaging library version
                                function setReceiveVersion(uint16 _version) external;
                                // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
                                // @param _srcChainId - the chainId of the source chain
                                // @param _srcAddress - the contract address of the source contract at the source chain
                                function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.6.0 <0.8.0;
                            /*
                             * @dev Provides information about the current execution context, including the
                             * sender of the transaction and its data. While these are generally available
                             * via msg.sender and msg.data, they should not be accessed in such a direct
                             * manner, since when dealing with GSN meta-transactions the account sending and
                             * paying for execution may not be the actual sender (as far as an application
                             * is concerned).
                             *
                             * This contract is only required for intermediate, library-like contracts.
                             */
                            abstract contract Context {
                                function _msgSender() internal view virtual returns (address payable) {
                                    return msg.sender;
                                }
                                function _msgData() internal view virtual returns (bytes memory) {
                                    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                                    return msg.data;
                                }
                            }
                            

                            File 8 of 10: NonceContract
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity 0.7.6;
                            import "./interfaces/ILayerZeroEndpoint.sol";
                            contract NonceContract {
                                ILayerZeroEndpoint public immutable endpoint;
                                // outboundNonce = [dstChainId][remoteAddress + localAddress]
                                mapping(uint16 => mapping(bytes => uint64)) public outboundNonce;
                                constructor(address _endpoint) {
                                    endpoint = ILayerZeroEndpoint(_endpoint);
                                }
                                function increment(uint16 _chainId, address _ua, bytes calldata _path) external returns (uint64) {
                                    require(endpoint.getSendLibraryAddress(_ua) == msg.sender, "NonceContract: msg.sender is not valid sendlibrary");
                                    return ++outboundNonce[_chainId][_path];
                                }
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.5.0;
                            import "./ILayerZeroUserApplicationConfig.sol";
                            interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
                                // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
                                // @param _dstChainId - the destination chain identifier
                                // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
                                // @param _payload - a custom bytes payload to send to the destination contract
                                // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
                                // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
                                // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
                                function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                                // @notice used by the messaging library to publish verified payload
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source contract (as bytes) at the source chain
                                // @param _dstAddress - the address on destination chain
                                // @param _nonce - the unbound message ordering nonce
                                // @param _gasLimit - the gas limit for external contract execution
                                // @param _payload - verified payload to send to the destination contract
                                function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
                                // @notice get the inboundNonce of a receiver from a source chain which could be EVM or non-EVM chain
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
                                // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
                                // @param _srcAddress - the source chain contract address
                                function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
                                // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
                                // @param _dstChainId - the destination chain identifier
                                // @param _userApplication - the user app address on this EVM chain
                                // @param _payload - the custom message to send over LayerZero
                                // @param _payInZRO - if false, user app pays the protocol fee in native token
                                // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
                                function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                                // @notice get this Endpoint's immutable source identifier
                                function getChainId() external view returns (uint16);
                                // @notice the interface to retry failed message on this Endpoint destination
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                // @param _payload - the payload to be retried
                                function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
                                // @notice query if any STORED payload (message blocking) at the endpoint.
                                // @param _srcChainId - the source chain identifier
                                // @param _srcAddress - the source chain contract address
                                function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
                                // @notice query if the _libraryAddress is valid for sending msgs.
                                // @param _userApplication - the user app address on this EVM chain
                                function getSendLibraryAddress(address _userApplication) external view returns (address);
                                // @notice query if the _libraryAddress is valid for receiving msgs.
                                // @param _userApplication - the user app address on this EVM chain
                                function getReceiveLibraryAddress(address _userApplication) external view returns (address);
                                // @notice query if the non-reentrancy guard for send() is on
                                // @return true if the guard is on. false otherwise
                                function isSendingPayload() external view returns (bool);
                                // @notice query if the non-reentrancy guard for receive() is on
                                // @return true if the guard is on. false otherwise
                                function isReceivingPayload() external view returns (bool);
                                // @notice get the configuration of the LayerZero messaging library of the specified version
                                // @param _version - messaging library version
                                // @param _chainId - the chainId for the pending config change
                                // @param _userApplication - the contract address of the user application
                                // @param _configType - type of configuration. every messaging library has its own convention.
                                function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                                // @notice get the send() LayerZero messaging library version
                                // @param _userApplication - the contract address of the user application
                                function getSendVersion(address _userApplication) external view returns (uint16);
                                // @notice get the lzReceive() LayerZero messaging library version
                                // @param _userApplication - the contract address of the user application
                                function getReceiveVersion(address _userApplication) external view returns (uint16);
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.5.0;
                            interface ILayerZeroUserApplicationConfig {
                                // @notice set the configuration of the LayerZero messaging library of the specified version
                                // @param _version - messaging library version
                                // @param _chainId - the chainId for the pending config change
                                // @param _configType - type of configuration. every messaging library has its own convention.
                                // @param _config - configuration in the bytes. can encode arbitrary content.
                                function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
                                // @notice set the send() LayerZero messaging library version to _version
                                // @param _version - new messaging library version
                                function setSendVersion(uint16 _version) external;
                                // @notice set the lzReceive() LayerZero messaging library version to _version
                                // @param _version - new messaging library version
                                function setReceiveVersion(uint16 _version) external;
                                // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
                                // @param _srcChainId - the chainId of the source chain
                                // @param _srcAddress - the contract address of the source contract at the source chain
                                function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
                            }
                            

                            File 9 of 10: OptimizedTransparentUpgradeableProxy
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (interfaces/draft-IERC1822.sol)
                            pragma solidity ^0.8.0;
                            /**
                             * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
                             * proxy whose upgrades are fully controlled by the current implementation.
                             */
                            interface IERC1822Proxiable {
                                /**
                                 * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
                                 * address.
                                 *
                                 * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
                                 * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
                                 * function revert if invoked through a proxy.
                                 */
                                function proxiableUUID() external view returns (bytes32);
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Proxy.sol)
                            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
                            // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/ERC1967/ERC1967Upgrade.sol)
                            pragma solidity ^0.8.2;
                            import "../beacon/IBeacon.sol";
                            import "../../interfaces/draft-IERC1822.sol";
                            import "../../utils/Address.sol";
                            import "../../utils/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 _upgradeToAndCallUUPS(
                                    address newImplementation,
                                    bytes memory data,
                                    bool forceCall
                                ) internal {
                                    // Upgrades from old implementations will perform a rollback test. This test requires the new
                                    // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                                    // this special case will break upgrade paths from old UUPS implementation to new ones.
                                    if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
                                        _setImplementation(newImplementation);
                                    } else {
                                        try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                                            require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                                        } catch {
                                            revert("ERC1967Upgrade: new implementation is not UUPS");
                                        }
                                        _upgradeToAndCall(newImplementation, data, forceCall);
                                    }
                                }
                                /**
                                 * @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 virtual 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
                            // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/Proxy.sol)
                            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 internal 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
                            // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
                            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
                            // OpenZeppelin Contracts (last updated v4.5.0-rc.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
                                            assembly {
                                                let returndata_size := mload(returndata)
                                                revert(add(32, returndata), returndata_size)
                                            }
                                        } else {
                                            revert(errorMessage);
                                        }
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
                            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
                                    }
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            // OpenZeppelin Contracts v4.4.1 (proxy/transparent/TransparentUpgradeableProxy.sol)
                            pragma solidity ^0.8.0;
                            import "../openzeppelin/proxy/ERC1967/ERC1967Proxy.sol";
                            /**
                             * @dev This contract implements a proxy that is upgradeable by an admin.
                             *
                             * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
                             * clashing], which can potentially be used in an attack, this contract uses the
                             * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
                             * things that go hand in hand:
                             *
                             * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
                             * that call matches one of the admin functions exposed by the proxy itself.
                             * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
                             * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
                             * "admin cannot fallback to proxy target".
                             *
                             * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
                             * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
                             * to sudden errors when trying to call a function from the proxy implementation.
                             *
                             * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
                             * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
                             */
                            contract OptimizedTransparentUpgradeableProxy is ERC1967Proxy {
                                address internal immutable _ADMIN;
                                /**
                                 * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                                 * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
                                 */
                                constructor(
                                    address _logic,
                                    address admin_,
                                    bytes memory _data
                                ) payable ERC1967Proxy(_logic, _data) {
                                    assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                                    _ADMIN = admin_;
                                    // still store it to work with EIP-1967
                                    bytes32 slot = _ADMIN_SLOT;
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        sstore(slot, admin_)
                                    }
                                    emit AdminChanged(address(0), admin_);
                                }
                                /**
                                 * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                                 */
                                modifier ifAdmin() {
                                    if (msg.sender == _getAdmin()) {
                                        _;
                                    } else {
                                        _fallback();
                                    }
                                }
                                /**
                                 * @dev Returns the current admin.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                                 *
                                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                                 * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                                 */
                                function admin() external ifAdmin returns (address admin_) {
                                    admin_ = _getAdmin();
                                }
                                /**
                                 * @dev Returns the current implementation.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                                 *
                                 * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                                 * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                                 * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                                 */
                                function implementation() external ifAdmin returns (address implementation_) {
                                    implementation_ = _implementation();
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                                 */
                                function upgradeTo(address newImplementation) external ifAdmin {
                                    _upgradeToAndCall(newImplementation, bytes(""), false);
                                }
                                /**
                                 * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                                 * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                                 * proxied contract.
                                 *
                                 * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                                 */
                                function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                                    _upgradeToAndCall(newImplementation, data, true);
                                }
                                /**
                                 * @dev Returns the current admin.
                                 */
                                function _admin() internal view virtual returns (address) {
                                    return _getAdmin();
                                }
                                /**
                                 * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                                 */
                                function _beforeFallback() internal virtual override {
                                    require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                                    super._beforeFallback();
                                }
                                function _getAdmin() internal view virtual override returns (address) {
                                    return _ADMIN;
                                }
                            }
                            

                            File 10 of 10: TreasuryV2
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity 0.7.6;
                            import "./interfaces/ILayerZeroTreasury.sol";
                            import "@openzeppelin/contracts/access/Ownable.sol";
                            import "@openzeppelin/contracts/math/SafeMath.sol";
                            import "./interfaces/ILayerZeroUltraLightNodeV2.sol";
                            contract TreasuryV2 is ILayerZeroTreasury, Ownable {
                                using SafeMath for uint;
                                uint public nativeBP;
                                uint public zroFee;
                                bool public feeEnabled;
                                bool public zroEnabled;
                                ILayerZeroUltraLightNodeV2 public uln;
                                event NativeBP(uint bp);
                                event ZroFee(uint zroFee);
                                event FeeEnabled(bool feeEnabled);
                                event ZroEnabled(bool zroEnabled);
                                constructor(address _ulnv2) {
                                    uln = ILayerZeroUltraLightNodeV2(_ulnv2);
                                }
                                function getFees(bool payInZro, uint relayerFee, uint oracleFee) external view override returns (uint) {
                                    if (feeEnabled) {
                                        if (payInZro) {
                                            require(zroEnabled, "LayerZero: ZRO is not enabled");
                                            return zroFee;
                                        } else {
                                            return relayerFee.add(oracleFee).mul(nativeBP).div(10000);
                                        }
                                    }
                                    return 0;
                                }
                                function setFeeEnabled(bool _feeEnabled) external onlyOwner {
                                    feeEnabled = _feeEnabled;
                                    emit FeeEnabled(_feeEnabled);
                                }
                                function setZroEnabled(bool _zroEnabled) external onlyOwner {
                                    zroEnabled = _zroEnabled;
                                    emit ZroEnabled(_zroEnabled);
                                }
                                function setNativeBP(uint _nativeBP) external onlyOwner {
                                    nativeBP = _nativeBP;
                                    emit NativeBP(_nativeBP);
                                }
                                function setZroFee(uint _zroFee) external onlyOwner {
                                    zroFee = _zroFee;
                                    emit ZroFee(_zroFee);
                                }
                                function withdrawZROFromULN(address _to, uint _amount) external onlyOwner {
                                    uln.withdrawZRO(_to, _amount);
                                }
                                function withdrawNativeFromULN(address payable _to, uint _amount) external onlyOwner {
                                    uln.withdrawNative(_to, _amount);
                                }
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.5.0;
                            interface ILayerZeroTreasury {
                                function getFees(bool payInZro, uint relayerFee, uint oracleFee) external view returns (uint);
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            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 () {
                                    address msgSender = _msgSender();
                                    _owner = msgSender;
                                    emit OwnershipTransferred(address(0), msgSender);
                                }
                                /**
                                 * @dev Returns the address of the current owner.
                                 */
                                function owner() public view virtual returns (address) {
                                    return _owner;
                                }
                                /**
                                 * @dev Throws if called by any account other than the owner.
                                 */
                                modifier onlyOwner() {
                                    require(owner() == _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 {
                                    emit OwnershipTransferred(_owner, address(0));
                                    _owner = address(0);
                                }
                                /**
                                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                                 * Can only be called by the current owner.
                                 */
                                function transferOwnership(address newOwner) public virtual onlyOwner {
                                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                                    emit OwnershipTransferred(_owner, newOwner);
                                    _owner = newOwner;
                                }
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity ^0.7.0;
                            /**
                             * @dev Wrappers over Solidity's arithmetic operations with added overflow
                             * checks.
                             *
                             * Arithmetic operations in Solidity wrap on overflow. This can easily result
                             * in bugs, because programmers usually assume that an overflow raises an
                             * error, which is the standard behavior in high level programming languages.
                             * `SafeMath` restores this intuition by reverting the transaction when an
                             * operation overflows.
                             *
                             * Using this library instead of the unchecked operations eliminates an entire
                             * class of bugs, so it's recommended to use it always.
                             */
                            library SafeMath {
                                /**
                                 * @dev Returns the addition of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    uint256 c = a + b;
                                    if (c < a) return (false, 0);
                                    return (true, c);
                                }
                                /**
                                 * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    if (b > a) return (false, 0);
                                    return (true, a - b);
                                }
                                /**
                                 * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                                    // benefit is lost if 'b' is also tested.
                                    // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                                    if (a == 0) return (true, 0);
                                    uint256 c = a * b;
                                    if (c / a != b) return (false, 0);
                                    return (true, c);
                                }
                                /**
                                 * @dev Returns the division of two unsigned integers, with a division by zero flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    if (b == 0) return (false, 0);
                                    return (true, a / b);
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                                 *
                                 * _Available since v3.4._
                                 */
                                function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                    if (b == 0) return (false, 0);
                                    return (true, a % b);
                                }
                                /**
                                 * @dev Returns the addition of two unsigned integers, reverting on
                                 * overflow.
                                 *
                                 * Counterpart to Solidity's `+` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Addition cannot overflow.
                                 */
                                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                                    uint256 c = a + b;
                                    require(c >= a, "SafeMath: addition overflow");
                                    return c;
                                }
                                /**
                                 * @dev Returns the subtraction of two unsigned integers, reverting on
                                 * overflow (when the result is negative).
                                 *
                                 * Counterpart to Solidity's `-` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Subtraction cannot overflow.
                                 */
                                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                                    require(b <= a, "SafeMath: subtraction overflow");
                                    return a - b;
                                }
                                /**
                                 * @dev Returns the multiplication of two unsigned integers, reverting on
                                 * overflow.
                                 *
                                 * Counterpart to Solidity's `*` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Multiplication cannot overflow.
                                 */
                                function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                                    if (a == 0) return 0;
                                    uint256 c = a * b;
                                    require(c / a == b, "SafeMath: multiplication overflow");
                                    return c;
                                }
                                /**
                                 * @dev Returns the integer division of two unsigned integers, reverting on
                                 * division by zero. The result is rounded towards zero.
                                 *
                                 * Counterpart to Solidity's `/` operator. Note: this function uses a
                                 * `revert` opcode (which leaves remaining gas untouched) while Solidity
                                 * uses an invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function div(uint256 a, uint256 b) internal pure returns (uint256) {
                                    require(b > 0, "SafeMath: division by zero");
                                    return a / b;
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                                 * reverting when dividing by zero.
                                 *
                                 * Counterpart to Solidity's `%` operator. This function uses a `revert`
                                 * opcode (which leaves remaining gas untouched) while Solidity uses an
                                 * invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                                    require(b > 0, "SafeMath: modulo by zero");
                                    return a % b;
                                }
                                /**
                                 * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                                 * overflow (when the result is negative).
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {trySub}.
                                 *
                                 * Counterpart to Solidity's `-` operator.
                                 *
                                 * Requirements:
                                 *
                                 * - Subtraction cannot overflow.
                                 */
                                function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                    require(b <= a, errorMessage);
                                    return a - b;
                                }
                                /**
                                 * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                                 * division by zero. The result is rounded towards zero.
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {tryDiv}.
                                 *
                                 * Counterpart to Solidity's `/` operator. Note: this function uses a
                                 * `revert` opcode (which leaves remaining gas untouched) while Solidity
                                 * uses an invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                    require(b > 0, errorMessage);
                                    return a / b;
                                }
                                /**
                                 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                                 * reverting with custom message when dividing by zero.
                                 *
                                 * CAUTION: This function is deprecated because it requires allocating memory for the error
                                 * message unnecessarily. For custom revert reasons use {tryMod}.
                                 *
                                 * Counterpart to Solidity's `%` operator. This function uses a `revert`
                                 * opcode (which leaves remaining gas untouched) while Solidity uses an
                                 * invalid opcode to revert (consuming all remaining gas).
                                 *
                                 * Requirements:
                                 *
                                 * - The divisor cannot be zero.
                                 */
                                function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                    require(b > 0, errorMessage);
                                    return a % b;
                                }
                            }
                            // SPDX-License-Identifier: BUSL-1.1
                            pragma solidity >=0.7.0;
                            pragma abicoder v2;
                            interface ILayerZeroUltraLightNodeV2 {
                                // Relayer functions
                                function validateTransactionProof(uint16 _srcChainId, address _dstAddress, uint _gasLimit, bytes32 _lookupHash, bytes32 _blockData, bytes calldata _transactionProof) external;
                                // an Oracle delivers the block data using updateHash()
                                function updateHash(uint16 _srcChainId, bytes32 _lookupHash, uint _confirmations, bytes32 _blockData) external;
                                // can only withdraw the receivable of the msg.sender
                                function withdrawNative(address payable _to, uint _amount) external;
                                function withdrawZRO(address _to, uint _amount) external;
                                // view functions
                                function getAppConfig(uint16 _remoteChainId, address _userApplicationAddress) external view returns (ApplicationConfiguration memory);
                                function accruedNativeFee(address _address) external view returns (uint);
                                struct ApplicationConfiguration {
                                    uint16 inboundProofLibraryVersion;
                                    uint64 inboundBlockConfirmations;
                                    address relayer;
                                    uint16 outboundProofType;
                                    uint64 outboundBlockConfirmations;
                                    address oracle;
                                }
                                event HashReceived(uint16 indexed srcChainId, address indexed oracle, bytes32 lookupHash, bytes32 blockData, uint confirmations);
                                event RelayerParams(bytes adapterParams, uint16 outboundProofType);
                                event Packet(bytes payload);
                                event InvalidDst(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);
                                event PacketReceived(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);
                                event AppConfigUpdated(address indexed userApplication, uint indexed configType, bytes newConfig);
                                event AddInboundProofLibraryForChain(uint16 indexed chainId, address lib);
                                event EnableSupportedOutboundProof(uint16 indexed chainId, uint16 proofType);
                                event SetChainAddressSize(uint16 indexed chainId, uint size);
                                event SetDefaultConfigForChainId(uint16 indexed chainId, uint16 inboundProofLib, uint64 inboundBlockConfirm, address relayer, uint16 outboundProofType, uint64 outboundBlockConfirm, address oracle);
                                event SetDefaultAdapterParamsForChainId(uint16 indexed chainId, uint16 indexed proofType, bytes adapterParams);
                                event SetLayerZeroToken(address indexed tokenAddress);
                                event SetRemoteUln(uint16 indexed chainId, bytes32 uln);
                                event SetTreasury(address indexed treasuryAddress);
                                event WithdrawZRO(address indexed msgSender, address indexed to, uint amount);
                                event WithdrawNative(address indexed msgSender, address indexed to, uint amount);
                            }
                            // SPDX-License-Identifier: MIT
                            pragma solidity >=0.6.0 <0.8.0;
                            /*
                             * @dev Provides information about the current execution context, including the
                             * sender of the transaction and its data. While these are generally available
                             * via msg.sender and msg.data, they should not be accessed in such a direct
                             * manner, since when dealing with GSN meta-transactions the account sending and
                             * paying for execution may not be the actual sender (as far as an application
                             * is concerned).
                             *
                             * This contract is only required for intermediate, library-like contracts.
                             */
                            abstract contract Context {
                                function _msgSender() internal view virtual returns (address payable) {
                                    return msg.sender;
                                }
                                function _msgData() internal view virtual returns (bytes memory) {
                                    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                                    return msg.data;
                                }
                            }