// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;
import {Ownable2Step} from "openzeppelin-solidity/contracts/access/Ownable2Step.sol";
import {Pausable} from "openzeppelin-solidity/contracts/security/Pausable.sol";
import {Address} from "openzeppelin-solidity/contracts/utils/Address.sol";
import {IMagpieRouterV3} from "./interfaces/IMagpieRouterV3.sol";
import {LibAsset} from "./libraries/LibAsset.sol";
import {LibRouter, SwapData} from "./libraries/LibRouter.sol";
error ExpiredTransaction();
error InsufficientAmountOut();
error InvalidCall();
error InvalidCommand();
error InvalidTransferFromCall();
error ApprovalFailed();
error TransferFromFailed();
error TransferFailed();
error UniswapV3InvalidAmount();
error InvalidCaller();
error InvalidAmountIn();
error InvalidSignature();
error InvalidOutput();
error InvalidNativeAmount();
enum CommandAction {
    Call, // Represents a generic call to a function within a contract.
    Approval, // Represents an approval operation.
    TransferFrom, // Indicates a transfer-from operation.
    Transfer, // Represents a direct transfer operation.
    Wrap, // This action is used for wrapping native tokens.
    Unwrap, // This action is used for unwrapping native tokens.
    Balance, // Checks the balance of an account or contract for a specific asset.
    Math,
    Comparison,
    EstimateGasStart,
    EstimateGasEnd
}
contract MagpieRouterV3 is IMagpieRouterV3, Ownable2Step, Pausable {
    using LibAsset for address;
    mapping(address => bool) public internalCaller;
    mapping(address => bool) public bridge;
    address public swapFeeAddress;
    /// @dev Restricts swap functions with signatures to only be called by whitelisted internal caller.
    modifier onlyInternalCaller() {
        if (!internalCaller[msg.sender]) {
            revert InvalidCaller();
        }
        _;
    }
    /// @dev Restricts swap functions with signatures to be called only by bridge.
    modifier onlyBridge() {
        if (!bridge[msg.sender]) {
            revert InvalidCaller();
        }
        _;
    }
    /// @dev See {IMagpieRouterV3-updateInternalCaller}
    function updateInternalCaller(address caller, bool value) external onlyOwner {
        internalCaller[caller] = value;
        emit UpdateInternalCaller(msg.sender, caller, value);
    }
    /// @dev See {IMagpieRouterV3-updateBridge}
    function updateBridge(address caller, bool value) external onlyOwner {
        bridge[caller] = value;
        emit UpdateBridge(msg.sender, caller, value);
    }
    /// @dev See {IMagpieRouterV3-updateSwapFeeAddress}
    function updateSwapFeeAddress(address value) external onlyOwner {
        swapFeeAddress = value;
    }
    /// @dev See {IMagpieRouterV3-pause}
    function pause() public onlyOwner whenNotPaused {
        _pause();
    }
    /// @dev See {IMagpieRouterV3-unpause}
    function unpause() public onlyOwner whenPaused {
        _unpause();
    }
    /// @dev See {IMagpieRouterV3-multicall}
    function multicall(bytes[] calldata data) external onlyOwner returns (bytes[] memory results) {
        results = new bytes[](data.length);
        for (uint256 i = 0; i < data.length; i++) {
            results[i] = Address.functionDelegateCall(address(this), data[i]);
        }
        return results;
    }
    /// @dev Handle uniswapV3SwapCallback requests from any protocol that is based on UniswapV3. We dont check for factory since this contract is not supposed to store tokens. We protect the user by handling amountOutMin check at the end of execution by comparing starting and final balance at the destination address.
    fallback() external {
        int256 amount0Delta;
        int256 amount1Delta;
        address assetIn;
        uint256 callDataSize;
        assembly {
            amount0Delta := calldataload(4)
            amount1Delta := calldataload(36)
            assetIn := shr(96, calldataload(132))
            callDataSize := calldatasize()
        }
        if (callDataSize != 164) {
            revert InvalidCall();
        }
        if (amount0Delta <= 0 && amount1Delta <= 0) {
            revert UniswapV3InvalidAmount();
        }
        uint256 amount = amount0Delta > 0 ? uint256(amount0Delta) : uint256(amount1Delta);
        assetIn.transfer(msg.sender, amount);
    }
    /// @dev Retrieves the address to be used for a swap operation.
    /// @param swapData The data structure containing information about the swap.
    /// @param useCaller Boolean indicating whether to use the caller's address.
    /// @param checkSignature Boolean indicating whether to validate the signature.
    /// @return fromAddress The address to be used for the swap operation.
    function getFromAddress(
        SwapData memory swapData,
        bool useCaller,
        bool checkSignature
    ) private view returns (address fromAddress) {
        if (checkSignature) {
            bool hasAffiliate = swapData.hasAffiliate;
            uint256 messagePtr;
            uint256 messageLength = hasAffiliate ? 384 : 320;
            assembly {
                messagePtr := mload(0x40)
                mstore(0x40, add(messagePtr, messageLength))
                switch hasAffiliate
                case 1 {
                    // keccak256("Swap(address router,address sender,address recipient,address fromAsset,address toAsset,uint256 deadline,uint256 amountOutMin,uint256 swapFee,uint256 amountIn,address affiliate,uint256 affiliateFee)")
                    mstore(messagePtr, 0x64d67eff2ff010acba1b1df82fb327ba0dc6d2965ba6b0b472bc14c494c8b4f6)
                }
                default {
                    // keccak256("Swap(address router,address sender,address recipient,address fromAsset,address toAsset,uint256 deadline,uint256 amountOutMin,uint256 swapFee,uint256 amountIn)")
                    mstore(messagePtr, 0x783528850c43ab6adcc3a843186a6558aa806707dd0abb3d2909a2a70b7f22a3)
                }
            }
            fromAddress = LibRouter.verifySignature(
                // keccak256(bytes("Magpie Router")),
                0x86af987965544521ef5b52deabbeb812d3353977e11a2dbe7e0f4905d1e60721,
                // keccak256(bytes("3")),
                0x2a80e1ef1d7842f27f2e6be0972bb708b9a135c38860dbe73c27c3486c34f4de,
                swapData,
                messagePtr,
                messageLength,
                useCaller,
                2
            );
        } else {
            if (useCaller) {
                fromAddress = msg.sender;
            } else {
                revert InvalidCall();
            }
        }
    }
    /// @dev Swaps tokens based on the provided swap data.
    /// @param swapData The data structure containing information about the swap operation.
    /// @param fromAddress The address initiating the swap. This address is responsible for the input assets.
    /// @param fullAmountIn The full amount that was used for the operation. If its 0 then event wont be emited.
    /// @return amountOut The amount of tokens or assets received after the swap.
    /// @return gasUsed The amount of gas consumed by the recorded operation.
    function swap(
        SwapData memory swapData,
        address fromAddress,
        uint256 fullAmountIn
    ) private returns (uint256 amountOut, uint256 gasUsed) {
        address fromAssetAddress = swapData.fromAssetAddress;
        address toAssetAddress = swapData.toAssetAddress;
        address toAddress = swapData.toAddress;
        uint256 amountOutMin = swapData.amountOutMin;
        uint256 amountIn = swapData.amountIn;
        uint256 transferFromAmount;
        amountOut = toAssetAddress.getBalanceOf(toAddress);
        (transferFromAmount, gasUsed) = execute(fromAddress, fromAssetAddress);
        amountOut = toAssetAddress.getBalanceOf(toAddress) - amountOut;
        if (amountOut < amountOutMin) {
            revert InsufficientAmountOut();
        }
        if (!fromAssetAddress.isNative() && amountIn != transferFromAmount) {
            revert InvalidAmountIn();
        }
        if (fullAmountIn > 0) {
            emit Swap(fromAddress, toAddress, fromAssetAddress, toAssetAddress, fullAmountIn, amountOut);
        }
    }
    /// @dev See {IMagpieRouterV3-estimateSwapGas}
    function estimateSwapGas(
        bytes calldata
    ) external payable whenNotPaused returns (uint256 amountOut, uint256 gasUsed) {
        SwapData memory swapData = LibRouter.getData();
        address fromAddress = getFromAddress(swapData, true, true);
        if (swapData.hasPermit) {
            LibRouter.permit(swapData, fromAddress);
        }
        LibRouter.transferFees(swapData, fromAddress, swapData.swapFee == 0 ? address(0) : swapFeeAddress);
        (amountOut, gasUsed) = swap(
            swapData,
            fromAddress,
            swapData.amountIn + swapData.swapFee + swapData.affiliateFee
        );
    }
    /// @dev See {IMagpieRouterV3-swapWithMagpieSignature}
    function swapWithMagpieSignature(bytes calldata) external payable whenNotPaused returns (uint256 amountOut) {
        SwapData memory swapData = LibRouter.getData();
        address fromAddress = getFromAddress(swapData, true, true);
        if (swapData.hasPermit) {
            LibRouter.permit(swapData, fromAddress);
        }
        LibRouter.transferFees(swapData, fromAddress, swapData.swapFee == 0 ? address(0) : swapFeeAddress);
        (amountOut, ) = swap(swapData, fromAddress, swapData.amountIn + swapData.swapFee + swapData.affiliateFee);
    }
    /// @dev See {IMagpieRouterV3-swapWithUserSignature}
    function swapWithUserSignature(bytes calldata) external payable onlyInternalCaller returns (uint256 amountOut) {
        SwapData memory swapData = LibRouter.getData();
        if (msg.value > 0) {
            revert InvalidNativeAmount();
        }
        address fromAddress = getFromAddress(swapData, false, true);
        if (swapData.hasPermit) {
            LibRouter.permit(swapData, fromAddress);
        }
        LibRouter.transferFees(swapData, fromAddress, swapData.swapFee == 0 ? address(0) : swapFeeAddress);
        (amountOut, ) = swap(swapData, fromAddress, swapData.amountIn + swapData.swapFee + swapData.affiliateFee);
    }
    /// @dev See {IMagpieRouterV3-swapWithoutSignature}
    function swapWithoutSignature(bytes calldata) external payable onlyBridge returns (uint256 amountOut) {
        SwapData memory swapData = LibRouter.getData();
        address fromAddress = getFromAddress(swapData, true, false);
        (amountOut, ) = swap(swapData, fromAddress, 0);
    }
    /// @dev Prepares CommandData for command iteration.
    function getCommandData()
        private
        pure
        returns (uint16 commandsOffset, uint16 commandsOffsetEnd, uint16 outputsLength)
    {
        assembly {
            commandsOffset := add(70, shr(240, calldataload(68))) // dataOffset + dataLength
            commandsOffsetEnd := add(68, calldataload(36)) // commandsOffsetEnd / swapArgsOffset + swapArgsLength (swapArgsOffset - 32)
            outputsLength := shr(240, calldataload(70)) // dataOffset + 32
        }
    }
    /// @dev Handles the execution of a sequence of commands for the swap operation.
    /// @param fromAddress The address from which the assets will be swapped.
    /// @param fromAssetAddress The address of the asset to be swapped.
    /// @return transferFromAmount The amount transferred from the specified address.
    /// @return gasUsed The amount of gas used during the execution of the swap.
    function execute(
        address fromAddress,
        address fromAssetAddress
    ) private returns (uint256 transferFromAmount, uint256 gasUsed) {
        (uint16 commandsOffset, uint16 commandsOffsetEnd, uint16 outputsLength) = getCommandData();
        uint256 outputPtr;
        assembly {
            outputPtr := mload(0x40)
            mstore(0x40, add(outputPtr, outputsLength))
        }
        uint256 outputOffsetPtr = outputPtr;
        unchecked {
            for (uint256 i = commandsOffset; i < commandsOffsetEnd; ) {
                (transferFromAmount, gasUsed, outputOffsetPtr) = executeCommand(
                    i,
                    fromAddress,
                    fromAssetAddress,
                    outputPtr,
                    outputOffsetPtr,
                    transferFromAmount,
                    gasUsed
                );
                i += 9;
            }
        }
        if (outputOffsetPtr > outputPtr + outputsLength) {
            revert InvalidOutput();
        }
    }
    /// @dev Builds the input for a specific command.
    /// @param i Command data position.
    /// @param outputPtr Memory pointer of the currently available output.
    /// @return input Calculated input data.
    /// @return nativeAmount Native token amount.
    function getInput(uint256 i, uint256 outputPtr) private view returns (bytes memory input, uint256 nativeAmount) {
        assembly {
            let sequencesPositionEnd := shr(240, calldataload(add(i, 5)))
            input := mload(0x40)
            nativeAmount := 0
            let j := shr(240, calldataload(add(i, 3))) // sequencesPosition
            let inputOffsetPtr := add(input, 32)
            for {
            } lt(j, sequencesPositionEnd) {
            } {
                let sequenceType := shr(248, calldataload(j))
                switch sequenceType
                // NativeAmount
                case 0 {
                    switch shr(240, calldataload(add(j, 3)))
                    case 1 {
                        nativeAmount := mload(add(outputPtr, shr(240, calldataload(add(j, 1)))))
                    }
                    default {
                        let p := shr(240, calldataload(add(j, 1)))
                        nativeAmount := shr(shr(248, calldataload(p)), calldataload(add(p, 1)))
                    }
                    j := add(j, 5)
                }
                // Selector
                case 1 {
                    mstore(inputOffsetPtr, calldataload(shr(240, calldataload(add(j, 1)))))
                    inputOffsetPtr := add(inputOffsetPtr, 4)
                    j := add(j, 3)
                }
                // Address
                case 2 {
                    mstore(inputOffsetPtr, shr(96, calldataload(shr(240, calldataload(add(j, 1))))))
                    inputOffsetPtr := add(inputOffsetPtr, 32)
                    j := add(j, 3)
                }
                // Amount
                case 3 {
                    let p := shr(240, calldataload(add(j, 1)))
                    mstore(inputOffsetPtr, shr(shr(248, calldataload(p)), calldataload(add(p, 1))))
                    inputOffsetPtr := add(inputOffsetPtr, 32)
                    j := add(j, 3)
                }
                // Data
                case 4 {
                    let l := shr(240, calldataload(add(j, 3)))
                    calldatacopy(inputOffsetPtr, shr(240, calldataload(add(j, 1))), l)
                    inputOffsetPtr := add(inputOffsetPtr, l)
                    j := add(j, 5)
                }
                // CommandOutput
                case 5 {
                    mstore(inputOffsetPtr, mload(add(outputPtr, shr(240, calldataload(add(j, 1))))))
                    inputOffsetPtr := add(inputOffsetPtr, 32)
                    j := add(j, 3)
                }
                // RouterAddress
                case 6 {
                    mstore(inputOffsetPtr, address())
                    inputOffsetPtr := add(inputOffsetPtr, 32)
                    j := add(j, 1)
                }
                // SenderAddress
                case 7 {
                    mstore(inputOffsetPtr, caller())
                    inputOffsetPtr := add(inputOffsetPtr, 32)
                    j := add(j, 1)
                }
                default {
                    // InvalidSequenceType
                    mstore(0, 0xa90b6fde00000000000000000000000000000000000000000000000000000000)
                    revert(0, 4)
                }
            }
            mstore(input, sub(inputOffsetPtr, add(input, 32)))
            mstore(0x40, inputOffsetPtr)
        }
    }
    /// @dev Executes a command call with the given parameters.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    /// @param outputOffsetPtr The pointer to the offset of the output in memory.
    /// @return New outputOffsetPtr position.
    function executeCommandCall(uint256 i, uint256 outputPtr, uint256 outputOffsetPtr) private returns (uint256) {
        bytes memory input;
        uint256 nativeAmount;
        (input, nativeAmount) = getInput(i, outputPtr);
        uint256 outputLength;
        assembly {
            outputLength := shr(240, calldataload(add(i, 1)))
            switch shr(224, mload(add(input, 32))) // selector
            case 0 {
                // InvalidSelector
                mstore(0, 0x7352d91c00000000000000000000000000000000000000000000000000000000)
                revert(0, 4)
            }
            case 0x23b872dd {
                // Blacklist transferFrom in custom calls
                // InvalidTransferFromCall
                mstore(0, 0x1751a8e400000000000000000000000000000000000000000000000000000000)
                revert(0, 4)
            }
            default {
                let targetAddress := shr(96, calldataload(shr(240, calldataload(add(i, 7))))) // targetPosition
                if eq(targetAddress, address()) {
                    // InvalidCall
                    mstore(0, 0xae962d4e00000000000000000000000000000000000000000000000000000000)
                    revert(0, 4)
                }
                if iszero(
                    call(
                        gas(),
                        targetAddress,
                        nativeAmount,
                        add(input, 32),
                        mload(input),
                        outputOffsetPtr,
                        outputLength
                    )
                ) {
                    returndatacopy(0, 0, returndatasize())
                    revert(0, returndatasize())
                }
            }
        }
        outputOffsetPtr += outputLength;
        return outputOffsetPtr;
    }
    /// @dev Executes a command approval with the given parameters.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    function executeCommandApproval(uint256 i, uint256 outputPtr) private {
        (bytes memory input, ) = getInput(i, outputPtr);
        address self;
        address spender;
        uint256 amount;
        assembly {
            self := mload(add(input, 32))
            spender := mload(add(input, 64))
            amount := mload(add(input, 96))
        }
        self.approve(spender, amount);
    }
    /// @dev Executes a transfer command from a specific address and asset.
    /// @param i The command position.
    /// @param outputPtr The pointer to the output location in memory.
    /// @param fromAssetAddress The address of the asset to transfer from.
    /// @param fromAddress The address to transfer the asset from.
    /// @param transferFromAmount The accumulated amount of the asset to transfer.
    /// @return Accumulated transfer amount.
    function executeCommandTransferFrom(
        uint256 i,
        uint256 outputPtr,
        address fromAssetAddress,
        address fromAddress,
        uint256 transferFromAmount
    ) private returns (uint256) {
        (bytes memory input, ) = getInput(i, outputPtr);
        uint256 amount;
        assembly {
            amount := mload(add(input, 64))
        }
        if (amount > 0) {
            address to;
            assembly {
                to := mload(add(input, 32))
            }
            fromAssetAddress.transferFrom(fromAddress, to, amount);
            transferFromAmount += amount;
        }
        return transferFromAmount;
    }
    /// @dev Executes a transfer command with the given parameters.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    function executeCommandTransfer(uint256 i, uint256 outputPtr) private {
        (bytes memory input, ) = getInput(i, outputPtr);
        uint256 amount;
        assembly {
            amount := mload(add(input, 96))
        }
        if (amount > 0) {
            address self;
            address recipient;
            assembly {
                self := mload(add(input, 32))
                recipient := mload(add(input, 64))
            }
            self.transfer(recipient, amount);
        }
    }
    /// @dev Executes a wrap command with the given parameters.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    function executeCommandWrap(uint256 i, uint256 outputPtr) private {
        (bytes memory input, ) = getInput(i, outputPtr);
        address self;
        uint256 amount;
        assembly {
            self := mload(add(input, 32))
            amount := mload(add(input, 64))
        }
        self.wrap(amount);
    }
    /// @dev Executes an unwrap command with the given parameters.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    function executeCommandUnwrap(uint256 i, uint256 outputPtr) private {
        (bytes memory input, ) = getInput(i, outputPtr);
        address self;
        uint256 amount;
        assembly {
            self := mload(add(input, 32))
            amount := mload(add(input, 64))
        }
        self.unwrap(amount);
    }
    /// @dev Executes a balance command and returns the resulting balance.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    /// @param outputOffsetPtr The pointer to the offset of the output in memory.
    /// @return New outputOffsetPtr position.
    function executeCommandBalance(
        uint256 i,
        uint256 outputPtr,
        uint256 outputOffsetPtr
    ) private view returns (uint256) {
        (bytes memory input, ) = getInput(i, outputPtr);
        address self;
        uint256 amount;
        assembly {
            self := mload(add(input, 32))
        }
        amount = self.getBalance();
        assembly {
            mstore(outputOffsetPtr, amount)
        }
        outputOffsetPtr += 32;
        return outputOffsetPtr;
    }
    /// @dev Executes a mathematical command.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    /// @param outputOffsetPtr The pointer to the offset of the output in memory.
    /// @return New outputOffsetPtr position.
    function executeCommandMath(uint256 i, uint256 outputPtr, uint256 outputOffsetPtr) private view returns (uint256) {
        (bytes memory input, ) = getInput(i, outputPtr);
        assembly {
            function math(currentInputPtr) -> amount {
                let currentOutputPtr := mload(0x40)
                let j := 0
                let amount0 := 0
                let amount1 := 0
                let operator := 0
                for {
                } lt(j, 10) {
                } {
                    let pos := add(currentInputPtr, mul(j, 3))
                    let amount0Index := shr(248, mload(add(pos, 1)))
                    switch lt(amount0Index, 10)
                    case 1 {
                        amount0 := mload(add(currentOutputPtr, mul(amount0Index, 32)))
                    }
                    default {
                        amount0Index := sub(amount0Index, 10)
                        amount0 := mload(add(add(currentInputPtr, 32), mul(amount0Index, 32)))
                    }
                    let amount1Index := shr(248, mload(add(pos, 2)))
                    switch lt(amount1Index, 10)
                    case 1 {
                        amount1 := mload(add(currentOutputPtr, mul(amount1Index, 32)))
                    }
                    default {
                        amount1Index := sub(amount1Index, 10)
                        amount1 := mload(add(add(currentInputPtr, 32), mul(amount1Index, 32)))
                    }
                    operator := shr(248, mload(pos))
                    switch operator
                    // None
                    case 0 {
                        let finalPtr := add(currentOutputPtr, mul(sub(j, 1), 32))
                        amount := mload(finalPtr)
                        mstore(0x40, add(finalPtr, 32))
                        leave
                    }
                    // Add
                    case 1 {
                        mstore(add(currentOutputPtr, mul(j, 32)), add(amount0, amount1))
                    }
                    // Sub
                    case 2 {
                        mstore(add(currentOutputPtr, mul(j, 32)), sub(amount0, amount1))
                    }
                    // Mul
                    case 3 {
                        mstore(add(currentOutputPtr, mul(j, 32)), mul(amount0, amount1))
                    }
                    // Div
                    case 4 {
                        mstore(add(currentOutputPtr, mul(j, 32)), div(amount0, amount1))
                    }
                    // Pow
                    case 5 {
                        mstore(add(currentOutputPtr, mul(j, 32)), exp(amount0, amount1))
                    }
                    // Abs128
                    case 6 {
                        if gt(amount0, 170141183460469231731687303715884105727) {
                            let mask := sar(127, amount0)
                            amount0 := xor(amount0, mask)
                            amount0 := sub(amount0, mask)
                        }
                        mstore(add(currentOutputPtr, mul(j, 32)), amount0)
                    }
                    // Abs256
                    case 7 {
                        if gt(amount0, 57896044618658097711785492504343953926634992332820282019728792003956564819967) {
                            let mask := sar(255, amount0)
                            amount0 := xor(amount0, mask)
                            amount0 := sub(amount0, mask)
                        }
                        mstore(add(currentOutputPtr, mul(j, 32)), amount0)
                    }
                    // Shr
                    case 8 {
                        mstore(add(currentOutputPtr, mul(j, 32)), shr(amount0, amount1))
                    }
                    // Shl
                    case 9 {
                        mstore(add(currentOutputPtr, mul(j, 32)), shl(amount0, amount1))
                    }
                    j := add(j, 1)
                }
                let finalPtr := add(currentOutputPtr, mul(9, 32))
                amount := mload(finalPtr)
                mstore(0x40, add(finalPtr, 32))
            }
            mstore(outputOffsetPtr, math(add(input, 32)))
        }
        outputOffsetPtr += 32;
        return outputOffsetPtr;
    }
    /// @dev Executes a comparison command.
    /// @param i The command data position.
    /// @param outputPtr The pointer to the output location in memory.
    /// @param outputOffsetPtr The pointer to the offset of the output in memory.
    /// @return New outputOffsetPtr position.
    function executeCommandComparison(
        uint256 i,
        uint256 outputPtr,
        uint256 outputOffsetPtr
    ) private view returns (uint256) {
        (bytes memory input, ) = getInput(i, outputPtr);
        assembly {
            function comparison(currentInputPtr) -> amount {
                let currentOutputPtr := mload(0x40)
                let j := 0
                let amount0 := 0
                let amount1 := 0
                let amount2 := 0
                let amount3 := 0
                let operator := 0
                for {
                } lt(j, 6) {
                } {
                    let pos := add(currentInputPtr, mul(j, 5))
                    let amount0Index := shr(248, mload(add(pos, 1)))
                    switch lt(amount0Index, 6)
                    case 1 {
                        amount0 := mload(add(currentOutputPtr, mul(amount0Index, 32)))
                    }
                    default {
                        amount0Index := sub(amount0Index, 6)
                        amount0 := mload(add(add(currentInputPtr, 32), mul(amount0Index, 32)))
                    }
                    let amount1Index := shr(248, mload(add(pos, 2)))
                    switch lt(amount1Index, 6)
                    case 1 {
                        amount1 := mload(add(currentOutputPtr, mul(amount1Index, 32)))
                    }
                    default {
                        amount1Index := sub(amount1Index, 6)
                        amount1 := mload(add(add(currentInputPtr, 32), mul(amount1Index, 32)))
                    }
                    let amount2Index := shr(248, mload(add(pos, 3)))
                    switch lt(amount2Index, 6)
                    case 1 {
                        amount2 := mload(add(currentOutputPtr, mul(amount2Index, 32)))
                    }
                    default {
                        amount2Index := sub(amount2Index, 6)
                        amount2 := mload(add(add(currentInputPtr, 32), mul(amount2Index, 32)))
                    }
                    let amount3Index := shr(248, mload(add(pos, 4)))
                    switch lt(amount3Index, 6)
                    case 1 {
                        amount3 := mload(add(currentOutputPtr, mul(amount3Index, 32)))
                    }
                    default {
                        amount3Index := sub(amount3Index, 6)
                        amount3 := mload(add(add(currentInputPtr, 32), mul(amount3Index, 32)))
                    }
                    operator := shr(248, mload(pos))
                    switch operator
                    // None
                    case 0 {
                        let finalPtr := add(currentOutputPtr, mul(sub(j, 1), 32))
                        amount := mload(finalPtr)
                        mstore(0x40, add(finalPtr, 32))
                        leave
                    }
                    // Lt
                    case 1 {
                        switch lt(amount0, amount1)
                        case 1 {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount2)
                        }
                        default {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount3)
                        }
                    }
                    // Lte
                    case 2 {
                        switch or(lt(amount0, amount1), eq(amount0, amount1))
                        case 1 {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount2)
                        }
                        default {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount3)
                        }
                    }
                    // Gt
                    case 3 {
                        switch gt(amount0, amount1)
                        case 1 {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount2)
                        }
                        default {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount3)
                        }
                    }
                    // Gte
                    case 4 {
                        switch or(gt(amount0, amount1), eq(amount0, amount1))
                        case 1 {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount2)
                        }
                        default {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount3)
                        }
                    }
                    // Eq
                    case 5 {
                        switch eq(amount0, amount1)
                        case 1 {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount2)
                        }
                        default {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount3)
                        }
                    }
                    // Ne
                    case 6 {
                        switch eq(amount0, amount1)
                        case 1 {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount3)
                        }
                        default {
                            mstore(add(currentOutputPtr, mul(j, 32)), amount2)
                        }
                    }
                    j := add(j, 1)
                }
                let finalPtr := add(currentOutputPtr, mul(5, 32))
                amount := mload(finalPtr)
                mstore(0x40, add(finalPtr, 32))
            }
            mstore(outputOffsetPtr, comparison(add(input, 32)))
        }
        outputOffsetPtr += 32;
        return outputOffsetPtr;
    }
    /// @dev Handles the execution of the specified command commands for the swap operation.
    /// @param i The command data position.
    /// @param fromAddress The wallet / contract of the fromAssetAddress.
    /// @param fromAssetAddress The asset will be transfered from the user.
    /// @param outputPtr Starting position of the output memory pointer.
    /// @param outputOffsetPtr Current position of the output memory pointer.
    /// @param transferFromAmount Accumulated transferred amount.
    /// @param gasUsed Recorded gas between commands.
    function executeCommand(
        uint256 i,
        address fromAddress,
        address fromAssetAddress,
        uint256 outputPtr,
        uint256 outputOffsetPtr,
        uint256 transferFromAmount,
        uint256 gasUsed
    ) private returns (uint256, uint256, uint256) {
        CommandAction commandAction;
        assembly {
            commandAction := shr(248, calldataload(i))
        }
        if (commandAction == CommandAction.Call) {
            outputOffsetPtr = executeCommandCall(i, outputPtr, outputOffsetPtr);
        } else if (commandAction == CommandAction.Approval) {
            executeCommandApproval(i, outputPtr);
        } else if (commandAction == CommandAction.TransferFrom) {
            transferFromAmount = executeCommandTransferFrom(
                i,
                outputPtr,
                fromAssetAddress,
                fromAddress,
                transferFromAmount
            );
        } else if (commandAction == CommandAction.Transfer) {
            executeCommandTransfer(i, outputPtr);
        } else if (commandAction == CommandAction.Wrap) {
            executeCommandWrap(i, outputPtr);
        } else if (commandAction == CommandAction.Unwrap) {
            executeCommandUnwrap(i, outputPtr);
        } else if (commandAction == CommandAction.Balance) {
            outputOffsetPtr = executeCommandBalance(i, outputPtr, outputOffsetPtr);
        } else if (commandAction == CommandAction.Math) {
            outputOffsetPtr = executeCommandMath(i, outputPtr, outputOffsetPtr);
        } else if (commandAction == CommandAction.Comparison) {
            outputOffsetPtr = executeCommandComparison(i, outputPtr, outputOffsetPtr);
        } else if (commandAction == CommandAction.EstimateGasStart) {
            gasUsed = gasleft();
        } else if (commandAction == CommandAction.EstimateGasEnd) {
            gasUsed -= gasleft();
        } else {
            revert InvalidCommand();
        }
        return (transferFromAmount, gasUsed, outputOffsetPtr);
    }
    /// @dev Used to receive ethers
    receive() external payable {}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;
interface IMagpieRouterV3 {
    event UpdateInternalCaller(address indexed sender, address caller, bool value);
    /// @dev Allows the owner to update the whitelisted internal callers.
    /// @param caller Caller address.
    /// @param value Disable or enable the related caller.
    function updateInternalCaller(address caller, bool value) external;
    event UpdateBridge(address indexed sender, address caller, bool value);
    /// @dev Allows the owner to update the whitelisted bridges.
    /// @param caller Caller address.
    /// @param value Disable or enable the related caller.
    function updateBridge(address caller, bool value) external;
    /// @dev Allows the owner to update the swap fee receiver.
    /// @param value Swap fee receiver address.
    function updateSwapFeeAddress(address value) external;
    /// @dev Called by the owner to pause, triggers stopped state.
    function pause() external;
    /// @dev Called by the owner to unpause, returns to normal state.
    function unpause() external;
    event Swap(
        address indexed fromAddress,
        address indexed toAddress,
        address fromAssetAddress,
        address toAssetAddress,
        uint256 amountIn,
        uint256 amountOut
    );
    /// @dev Makes it possible to execute multiple functions in the same transaction.
    function multicall(bytes[] calldata data) external returns (bytes[] memory results);
    /// @dev Provides an external interface to estimate the gas cost of the last hop in a route.
    /// @return amountOut The amount received after swapping.
    /// @return gasUsed The cost of gas while performing the swap.
    function estimateSwapGas(bytes calldata swapArgs) external payable returns (uint256 amountOut, uint256 gasUsed);
    /// @dev Performs token swap with magpie signature.
    /// @return amountOut The amount received after swapping.
    function swapWithMagpieSignature(bytes calldata swapArgs) external payable returns (uint256 amountOut);
    /// @dev Performs token swap with a user signature.
    /// @return amountOut The amount received after swapping.
    function swapWithUserSignature(bytes calldata swapArgs) external payable returns (uint256 amountOut);
    /// @dev Performs token swap without a signature (data will be validated in the bridge) without triggering event.
    /// @return amountOut The amount received after swapping.
    function swapWithoutSignature(bytes calldata swapArgs) external payable returns (uint256 amountOut);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;
interface IWETH {
    function deposit() external payable;
    function transfer(address to, uint256 value) external returns (bool);
    function withdraw(uint256) external;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;
import "../interfaces/IWETH.sol";
error AssetNotReceived();
error ApprovalFailed();
error TransferFromFailed();
error TransferFailed();
error FailedWrap();
error FailedUnwrap();
library LibAsset {
    using LibAsset for address;
    address constant NATIVE_ASSETID = address(0);
    /// @dev Checks if the given address (self) represents a native asset (Ether).
    /// @param self The asset that will be checked for a native token.
    /// @return Flag to identify if the asset is native or not.
    function isNative(address self) internal pure returns (bool) {
        return self == NATIVE_ASSETID;
    }
    /// @dev Wraps the specified asset.
    /// @param self The asset that will be wrapped.
    function wrap(address self, uint256 amount) internal {
        uint256 ptr;
        assembly {
            ptr := mload(0x40)
            mstore(0x40, add(ptr, 4))
            mstore(ptr, 0xd0e30db000000000000000000000000000000000000000000000000000000000)
        }
        if (!execute(self, amount, ptr, 4, 0, 0)) {
            revert FailedWrap();
        }
    }
    /// @dev Unwraps the specified asset.
    /// @param self The asset that will be unwrapped.
    function unwrap(address self, uint256 amount) internal {
        uint256 ptr;
        assembly {
            ptr := mload(0x40)
            mstore(0x40, add(ptr, 36))
            mstore(ptr, 0x2e1a7d4d00000000000000000000000000000000000000000000000000000000)
            mstore(add(ptr, 4), amount)
        }
        if (!execute(self, 0, ptr, 36, 0, 0)) {
            revert FailedUnwrap();
        }
    }
    /// @dev Retrieves the balance of the current contract for a given asset (self).
    /// @param self Asset whose balance needs to be found.
    /// @return Balance of the specific asset.
    function getBalance(address self) internal view returns (uint256) {
        return getBalanceOf(self, address(this));
    }
    /// @dev Retrieves the balance of the target address for a given asset (self).
    /// @param self Asset whose balance needs to be found.
    /// @param targetAddress The address where the balance is checked from.
    /// @return amount Balance of the specific asset.
    function getBalanceOf(address self, address targetAddress) internal view returns (uint256 amount) {
        assembly {
            switch self
            case 0 {
                amount := balance(targetAddress)
            }
            default {
                let currentInputPtr := mload(0x40)
                mstore(0x40, add(currentInputPtr, 68))
                mstore(currentInputPtr, 0x70a0823100000000000000000000000000000000000000000000000000000000)
                mstore(add(currentInputPtr, 4), targetAddress)
                let currentOutputPtr := add(currentInputPtr, 36)
                if iszero(staticcall(gas(), self, currentInputPtr, 36, currentOutputPtr, 32)) {
                    returndatacopy(0, 0, returndatasize())
                    revert(0, returndatasize())
                }
                amount := mload(currentOutputPtr)
            }
        }
    }
    /// @dev Performs a safe transferFrom operation for a given asset (self) from one address (from) to another address (to).
    /// @param self Asset that will be transferred.
    /// @param from Address that will send the asset.
    /// @param to Address that will receive the asset.
    /// @param amount Transferred amount.
    function transferFrom(address self, address from, address to, uint256 amount) internal {
        uint256 ptr;
        assembly {
            ptr := mload(0x40)
            mstore(0x40, add(ptr, 100))
            mstore(ptr, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(ptr, 4), from)
            mstore(add(ptr, 36), to)
            mstore(add(ptr, 68), amount)
        }
        if (!execute(self, 0, ptr, 100, 0, 0)) {
            revert TransferFromFailed();
        }
    }
    /// @dev Transfers a given amount of an asset (self) to a recipient address (recipient).
    /// @param self Asset that will be transferred.
    /// @param recipient Address that will receive the transferred asset.
    /// @param amount Transferred amount.
    function transfer(address self, address recipient, uint256 amount) internal {
        if (self.isNative()) {
            (bool success, ) = payable(recipient).call{value: amount}("");
            if (!success) {
                revert TransferFailed();
            }
        } else {
            uint256 ptr;
            assembly {
                ptr := mload(0x40)
                mstore(0x40, add(ptr, 68))
                mstore(ptr, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
                mstore(add(ptr, 4), recipient)
                mstore(add(ptr, 36), amount)
            }
            if (!execute(self, 0, ptr, 68, 0, 0)) {
                revert TransferFailed();
            }
        }
    }
    /// @dev Approves a spender address (spender) to spend a specified amount of an asset (self).
    /// @param self The asset that will be approved.
    /// @param spender Address of a contract that will spend the owners asset.
    /// @param amount Asset amount that can be spent.
    function approve(address self, address spender, uint256 amount) internal {
        uint256 ptr;
        assembly {
            ptr := mload(0x40)
            mstore(0x40, add(ptr, 68))
            mstore(ptr, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(ptr, 4), spender)
            mstore(add(ptr, 36), amount)
        }
        if (!execute(self, 0, ptr, 68, 0, 0)) {
            assembly {
                mstore(add(ptr, 36), 0)
            }
            if (!execute(self, 0, ptr, 68, 0, 0)) {
                revert ApprovalFailed();
            }
            assembly {
                mstore(add(ptr, 36), amount)
            }
            if (!execute(self, 0, ptr, 68, 0, 0)) {
                revert ApprovalFailed();
            }
        }
    }
    function permit(
        address self,
        address owner,
        address spender,
        uint256 amount,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        assembly {
            let ptr := mload(0x40)
            mstore(0x40, add(ptr, 228))
            mstore(ptr, 0xd505accf00000000000000000000000000000000000000000000000000000000)
            mstore(add(ptr, 4), owner)
            mstore(add(ptr, 36), spender)
            mstore(add(ptr, 68), amount)
            mstore(add(ptr, 100), deadline)
            mstore(add(ptr, 132), v)
            mstore(add(ptr, 164), r)
            mstore(add(ptr, 196), s)
            let success := call(gas(), self, 0, ptr, 228, 0, 0)
        }
    }
    /// @dev Determines if a call was successful.
    /// @param target Address of the target contract.
    /// @param success To check if the call to the contract was successful or not.
    /// @param data The data was sent while calling the target contract.
    /// @return result The success of the call.
    function isSuccessful(address target, bool success, bytes memory data) private view returns (bool result) {
        if (success) {
            if (data.length == 0) {
                // isContract
                if (target.code.length > 0) {
                    result = true;
                }
            } else {
                assembly {
                    result := mload(add(data, 32))
                }
            }
        }
    }
    /// @dev Executes a low level call.
    function execute(
        address self,
        uint256 currentNativeAmount,
        uint256 currentInputPtr,
        uint256 currentInputLength,
        uint256 currentOutputPtr,
        uint256 outputLength
    ) internal returns (bool result) {
        assembly {
            function isSuccessfulCall(targetAddress) -> isSuccessful {
                switch iszero(returndatasize())
                case 1 {
                    if gt(extcodesize(targetAddress), 0) {
                        isSuccessful := 1
                    }
                }
                case 0 {
                    returndatacopy(0, 0, 32)
                    isSuccessful := gt(mload(0), 0)
                }
            }
            if iszero(
                call(
                    gas(),
                    self,
                    currentNativeAmount,
                    currentInputPtr,
                    currentInputLength,
                    currentOutputPtr,
                    outputLength
                )
            ) {
                returndatacopy(0, 0, returndatasize())
                revert(0, returndatasize())
            }
            result := isSuccessfulCall(self)
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;
import {LibAsset} from "../libraries/LibAsset.sol";
struct SwapData {
    address toAddress;
    address fromAssetAddress;
    address toAssetAddress;
    uint256 deadline;
    uint256 amountOutMin;
    uint256 swapFee;
    uint256 amountIn;
    bool hasPermit;
    bool hasAffiliate;
    address affiliateAddress;
    uint256 affiliateFee;
}
error InvalidSignature();
error ExpiredTransaction();
library LibRouter {
    using LibAsset for address;
    /// @dev Prepares SwapData from calldata
    function getData() internal view returns (SwapData memory swapData) {
        // dataOffset: 68 + 2
        assembly {
            let deadline := shr(
                shr(248, calldataload(132)), // dataOffset + 62
                calldataload(shr(240, calldataload(133))) // dataOffset + 62 + 1
            )
            if lt(deadline, timestamp()) {
                // ExpiredTransaction
                mstore(0, 0x931997cf00000000000000000000000000000000000000000000000000000000)
                revert(0, 4)
            }
            mstore(swapData, shr(96, calldataload(72))) // toAddress / dataOffset + 2
            mstore(add(swapData, 32), shr(96, calldataload(92))) // fromAssetAddress / dataOffset + 22
            mstore(add(swapData, 64), shr(96, calldataload(112))) // toAssetAddress / dataOffset + 42
            mstore(add(swapData, 96), deadline)
            mstore(
                add(swapData, 128),
                shr(
                    shr(248, calldataload(135)), // dataOffset + 62 + 3
                    calldataload(shr(240, calldataload(136))) // dataOffset + 62 + 4
                )
            ) // amountOutMin
            mstore(
                add(swapData, 160),
                shr(
                    shr(248, calldataload(138)), // dataOffset + 62 + 6
                    calldataload(shr(240, calldataload(139))) // dataOffset + 62 + 7
                )
            ) // swapFee
            mstore(
                add(swapData, 192),
                shr(
                    shr(248, calldataload(141)), // dataOffset + 62 + 9
                    calldataload(shr(240, calldataload(142))) // dataOffset + 62 + 10
                )
            ) // amountIn
            // calldataload(144) // r
            // calldataload(176) // s
            // shr(248, calldataload(208)) // v
            let hasPermit := gt(shr(248, calldataload(209)), 0) // permit v
            mstore(add(swapData, 224), hasPermit) // hasPermit
            // calldataload(210) // permit r
            // calldataload(242) // permit s
            // calldataload(274) // permit deadline
            switch hasPermit
            case 1 {
                let hasAffiliate := shr(248, calldataload(277))
                mstore(add(swapData, 256), hasAffiliate) // hasAffiliate
                if eq(hasAffiliate, 1) {
                    mstore(add(swapData, 288), shr(96, calldataload(278))) // affiliateAddress
                    mstore(
                        add(swapData, 320),
                        shr(shr(248, calldataload(298)), calldataload(shr(240, calldataload(299))))
                    ) // affiliateFee
                }
            }
            default {
                let hasAffiliate := shr(248, calldataload(210))
                mstore(add(swapData, 256), hasAffiliate) // hasAffiliate
                if eq(hasAffiliate, 1) {
                    mstore(add(swapData, 288), shr(96, calldataload(211))) // affiliateAddress
                    mstore(
                        add(swapData, 320),
                        shr(shr(248, calldataload(231)), calldataload(shr(240, calldataload(232))))
                    ) // affiliateFee
                }
            }
        }
    }
    /// @dev Transfers the required fees for the swap operation from the user's account.
    /// @param swapData The data structure containing the details of the swap operation, including fee information.
    /// @param fromAddress The address of the user from whom the fees will be deducted.
    /// @param swapFeeAddress The address of the swap fee receiver.
    function transferFees(SwapData memory swapData, address fromAddress, address swapFeeAddress) internal {
        if (swapData.swapFee > 0) {
            if (swapData.fromAssetAddress.isNative()) {
                swapData.fromAssetAddress.transfer(swapFeeAddress, swapData.swapFee);
            } else {
                swapData.fromAssetAddress.transferFrom(fromAddress, swapFeeAddress, swapData.swapFee);
            }
        }
        if (swapData.affiliateFee > 0) {
            if (swapData.fromAssetAddress.isNative()) {
                swapData.fromAssetAddress.transfer(swapData.affiliateAddress, swapData.affiliateFee);
            } else {
                swapData.fromAssetAddress.transferFrom(fromAddress, swapData.affiliateAddress, swapData.affiliateFee);
            }
        }
    }
    /// @dev Grants permission for the user's asset to be used in a swap operation.
    /// @param swapData The data structure containing the details of the swap operation.
    /// @param fromAddress The address of the user who is granting permission for their asset to be used.
    function permit(SwapData memory swapData, address fromAddress) internal {
        uint8 v;
        bytes32 r;
        bytes32 s;
        uint256 deadline;
        assembly {
            v := shr(248, calldataload(209))
            r := calldataload(210)
            s := calldataload(242)
            deadline := shr(shr(248, calldataload(274)), calldataload(shr(240, calldataload(275))))
        }
        swapData.fromAssetAddress.permit(
            fromAddress,
            address(this),
            swapData.amountIn + swapData.swapFee + swapData.affiliateFee,
            deadline,
            v,
            r,
            s
        );
    }
    /// @dev Recovers the signer's address from a hashed message and signature components.
    /// @param hash The hash of the message that was signed.
    /// @param r The `r` component of the signature.
    /// @param s The `s` component of the signature.
    /// @param v The `v` component of the signature.
    /// @return signer The address of the signer recovered from the signature.
    function recoverSigner(bytes32 hash, bytes32 r, bytes32 s, uint8 v) private pure returns (address signer) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            revert InvalidSignature();
        }
        if (v != 27 && v != 28) {
            revert InvalidSignature();
        }
        signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            revert InvalidSignature();
        }
    }
    function getDomainSeparator(bytes32 name, bytes32 version) private view returns (bytes32) {
        uint256 chainId;
        assembly {
            chainId := chainid()
        }
        return
            keccak256(
                abi.encode(
                    // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                    0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                    name,
                    version,
                    chainId,
                    address(this)
                )
            );
    }
    /// @dev Verifies the signature for a swap operation.
    /// @param swapData The SwapData struct containing swap details.
    /// @param messagePtr Pointer to the message data in memory.
    /// @param messageLength Length of the message data.
    /// @param useCaller Flag indicating whether to use the caller's address for verification.
    /// @param internalCallersSlot Slot in the internal callers storage for verification.
    /// @return fromAddress The address of the signer / or caller if the signature is valid.
    function verifySignature(
        bytes32 name,
        bytes32 version,
        SwapData memory swapData,
        uint256 messagePtr,
        uint256 messageLength,
        bool useCaller,
        uint8 internalCallersSlot
    ) internal view returns (address fromAddress) {
        bytes32 domainSeparator = getDomainSeparator(name, version);
        bytes32 digest;
        bytes32 r;
        bytes32 s;
        uint8 v;
        assembly {
            mstore(add(messagePtr, 32), address())
            mstore(add(messagePtr, 64), caller())
            mstore(add(messagePtr, 96), mload(swapData))
            mstore(add(messagePtr, 128), mload(add(swapData, 32)))
            mstore(add(messagePtr, 160), mload(add(swapData, 64)))
            mstore(add(messagePtr, 192), mload(add(swapData, 96)))
            mstore(add(messagePtr, 224), mload(add(swapData, 128)))
            mstore(add(messagePtr, 256), mload(add(swapData, 160)))
            mstore(add(messagePtr, 288), mload(add(swapData, 192)))
            // hasAffiliate
            if eq(mload(add(swapData, 256)), 1) {
                mstore(add(messagePtr, 320), mload(add(swapData, 288)))
                mstore(add(messagePtr, 352), mload(add(swapData, 320)))
            }
            let hash := keccak256(messagePtr, messageLength)
            messagePtr := mload(0x40)
            mstore(0x40, add(messagePtr, 66))
            mstore(messagePtr, "\\x19\\x01")
            mstore(add(messagePtr, 2), domainSeparator)
            mstore(add(messagePtr, 34), hash)
            digest := keccak256(messagePtr, 66)
            r := calldataload(144)
            s := calldataload(176)
            v := shr(248, calldataload(208))
        }
        if (useCaller) {
            address internalCaller = recoverSigner(digest, r, s, v);
            assembly {
                fromAddress := caller()
                mstore(0, internalCaller)
                mstore(0x20, internalCallersSlot)
                if iszero(eq(sload(keccak256(0, 0x40)), 1)) {
                    // InvalidSignature
                    mstore(0, 0x8baa579f00000000000000000000000000000000000000000000000000000000)
                    revert(0, 4)
                }
            }
        } else {
            fromAddress = recoverSigner(digest, r, s, v);
            if (fromAddress == address(this)) {
                revert InvalidSignature();
            }
        }
    }
}
// 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. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling 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
// OpenZeppelin Contracts (last updated v4.8.0) (access/Ownable2Step.sol)
pragma solidity ^0.8.0;
import "./Ownable.sol";
/**
 * @dev Contract module which provides 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} and {acceptOwnership}.
 *
 * This module is used through inheritance. It will make available all functions
 * from parent (Ownable).
 */
abstract contract Ownable2Step is Ownable {
    address private _pendingOwner;
    event OwnershipTransferStarted(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Returns the address of the pending owner.
     */
    function pendingOwner() public view virtual returns (address) {
        return _pendingOwner;
    }
    /**
     * @dev Starts the ownership transfer of the contract to a new account. Replaces the pending transfer if there is one.
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual override onlyOwner {
        _pendingOwner = newOwner;
        emit OwnershipTransferStarted(owner(), newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`) and deletes any pending owner.
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual override {
        delete _pendingOwner;
        super._transferOwnership(newOwner);
    }
    /**
     * @dev The new owner accepts the ownership transfer.
     */
    function acceptOwnership() public virtual {
        address sender = _msgSender();
        require(pendingOwner() == sender, "Ownable2Step: caller is not the new owner");
        _transferOwnership(sender);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);
    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);
    bool private _paused;
    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor() {
        _paused = false;
    }
    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }
    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }
    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }
    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }
    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }
    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }
    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}
// 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
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.
        return account.code.length > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }
    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}
// SPDX-License-Identifier: MIT
// 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;
    }
}

/** 
Website: https://destra.network
Telegram: https://t.me/DestraNetwork
Twitter: https://x.com/destranetwork
**/

// SPDX-License-Identifier: MIT

pragma solidity 0.8.17;

library Address {
  function isContract(address account) internal view returns (bool) {
    return account.code.length > 0;
  }

  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"
    );
  }

  function functionCall(
    address target,
    bytes memory data
  ) internal returns (bytes memory) {
    return
      functionCallWithValue(target, data, 0, "Address: low-level call failed");
  }

  function functionCall(
    address target,
    bytes memory data,
    string memory errorMessage
  ) internal returns (bytes memory) {
    return functionCallWithValue(target, data, 0, errorMessage);
  }

  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"
      );
  }

  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);
  }

  function functionStaticCall(
    address target,
    bytes memory data
  ) internal view returns (bytes memory) {
    return
      functionStaticCall(target, data, "Address: low-level static call failed");
  }

  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);
  }

  function functionDelegateCall(
    address target,
    bytes memory data
  ) internal returns (bytes memory) {
    return
      functionDelegateCall(
        target,
        data,
        "Address: low-level delegate call failed"
      );
  }

  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);
  }

  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);
    }
  }

  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);
    }
  }
}

abstract contract Context {
  function _msgSender() internal view virtual returns (address) {
    return msg.sender;
  }

  function _msgData() internal view virtual returns (bytes calldata) {
    return msg.data;
  }
}

interface IERC20 {
  function totalSupply() external view returns (uint256);

  function balanceOf(address account) external view returns (uint256);

  function transfer(address recipient, uint256 amount) external returns (bool);

  function allowance(
    address owner,
    address spender
  ) external view returns (uint256);

  function approve(address spender, uint256 amount) external returns (bool);

  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) external returns (bool);

  event Transfer(address indexed from, address indexed to, uint256 value);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}

interface IDEXFactory {
  function createPair(
    address tokenA,
    address tokenB
  ) external returns (address pair);
}

interface IDEXRouter {
  function factory() external pure returns (address);

  function WETH() external pure returns (address);

  function addLiquidityETH(
    address token,
    uint amountTokenDesired,
    uint amountTokenMin,
    uint amountETHMin,
    address to,
    uint deadline
  ) external payable returns (uint amountToken, uint amountETH, uint liquidity);

  function swapExactTokensForETHSupportingFeeOnTransferTokens(
    uint amountIn,
    uint amountOutMin,
    address[] calldata path,
    address to,
    uint deadline
  ) external;
}

abstract contract Ownable is Context {
  address private _owner;

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

  constructor() {
    _transferOwnership(_msgSender());
  }

  modifier onlyOwner() {
    _checkOwner();
    _;
  }

  function owner() public view virtual returns (address) {
    return _owner;
  }

  function _checkOwner() internal view virtual {
    require(owner() == _msgSender(), "Ownable: caller is not the owner");
  }

  function renounceOwnership() public virtual onlyOwner {
    _transferOwnership(address(0));
  }

  function transferOwnership(address newOwner) public virtual onlyOwner {
    require(newOwner != address(0), "Ownable: new owner is the zero address");
    _transferOwnership(newOwner);
  }

  function _transferOwnership(address newOwner) internal virtual {
    address oldOwner = _owner;
    _owner = newOwner;
    emit OwnershipTransferred(oldOwner, newOwner);
  }
}

contract DestraNetwork is IERC20, Ownable {
  using Address for address;

  address DEAD = 0x000000000000000000000000000000000000dEaD;
  address ZERO = 0x0000000000000000000000000000000000000000;

  string constant _name = "Destra Network";
  string constant _symbol = "DSync";
  uint8 constant _decimals = 18;

  uint256 _totalSupply = 1_000_000_000 * (10 ** _decimals);
  uint256 _maxBuyTxAmount = (_totalSupply * 1) / 100;
  uint256 _maxSellTxAmount = (_totalSupply * 1) / 100;
  uint256 _maxWalletSize = (_totalSupply * 1) / 100;

  mapping(address => uint256) _balances;
  mapping(address => mapping(address => uint256)) _allowances;

  mapping(uint256 => uint256) public swapBackCounter;
  uint256 public swapBackRateLimit = 3;

  mapping(address => bool) public isFeeExempt;
  mapping(address => bool) public isTxLimitExempt;
  mapping(address => bool) public isLiquidityCreator;

  uint256 marketingBuyFee = 500;
  uint256 marketingSellFee = 6000;
  uint256 liquidityBuyFee = 0;
  uint256 liquiditySellFee = 0;
  uint256 totalBuyFee = marketingBuyFee + liquidityBuyFee;
  uint256 totalSellFee = marketingSellFee + liquiditySellFee;
  uint256 feeDenominator = 10000;

  bool public transferTax = false;

  address payable public liquidityFeeReceiver = payable(0xa75bFFD82FFE8A5064A5b6122448221aCEbCf950);
  address payable public marketingFeeReceiver = payable(0xa75bFFD82FFE8A5064A5b6122448221aCEbCf950);

  IDEXRouter public router;
  address routerAddress = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
  mapping(address => bool) liquidityPools;
  address public pair;

  mapping(address => uint256) public blacklist;
  uint256 public blacklistCount;

  uint256 public launchBlock;
  uint256 public launchTimestamp;
  bool isTradingEnabled = false;

  bool public swapEnabled = false;
  uint256 public swapThreshold = _totalSupply / 1000;
  uint256 public swapAtMinimum = _totalSupply / 10000;
  bool inSwap;

  modifier swapping() {
    inSwap = true;
    _;
    inSwap = false;
  }

  mapping(address => bool) teamMembers;

  modifier onlyTeam() {
    require(
      teamMembers[_msgSender()] || msg.sender == owner(),
      "Caller is not a team member"
    );
    _;
  }

  event WalletBlacklisted(address, address, uint256);

  constructor() {
    router = IDEXRouter(routerAddress);
    pair = IDEXFactory(router.factory()).createPair(
      router.WETH(),
      address(this)
    );
    liquidityPools[pair] = true;
    _allowances[owner()][routerAddress] = type(uint256).max;
    _allowances[address(this)][routerAddress] = type(uint256).max;

    isFeeExempt[owner()] = true;
    isLiquidityCreator[owner()] = true;

    isTxLimitExempt[address(this)] = true;
    isTxLimitExempt[owner()] = true;
    isTxLimitExempt[routerAddress] = true;
    isTxLimitExempt[DEAD] = true;

    _balances[owner()] = _totalSupply;

    emit Transfer(address(0), owner(), _totalSupply);
  }

  receive() external payable {}

  function totalSupply() external view override returns (uint256) {
    return _totalSupply;
  }

  function decimals() external pure returns (uint8) {
    return _decimals;
  }

  function symbol() external pure returns (string memory) {
    return _symbol;
  }

  function name() external pure returns (string memory) {
    return _name;
  }

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

  function maxBuyTxTokens() external view returns (uint256) {
    return _maxBuyTxAmount / (10 ** _decimals);
  }

  function maxSellTxTokens() external view returns (uint256) {
    return _maxSellTxAmount / (10 ** _decimals);
  }

  function maxWalletTokens() external view returns (uint256) {
    return _maxWalletSize / (10 ** _decimals);
  }

  function balanceOf(address account) public view override returns (uint256) {
    return _balances[account];
  }

  function allowance(
    address holder,
    address spender
  ) external view override returns (uint256) {
    return _allowances[holder][spender];
  }

  function approve(
    address spender,
    uint256 amount
  ) public override returns (bool) {
    _allowances[msg.sender][spender] = amount;
    emit Approval(msg.sender, spender, amount);
    return true;
  }

  function approveMaxAmount(address spender) external returns (bool) {
    return approve(spender, type(uint256).max);
  }

  function setTeamMember(address _team, bool _enabled) external onlyOwner {
    teamMembers[_team] = _enabled;
  }

  function airdrop(
    address[] calldata addresses,
    uint256[] calldata amounts
  ) external onlyOwner {
    require(addresses.length > 0 && amounts.length == addresses.length);
    address from = msg.sender;

    for (uint i = 0; i < addresses.length; i++) {
      if (!liquidityPools[addresses[i]] && !isLiquidityCreator[addresses[i]]) {
        _basicTransfer(from, addresses[i], amounts[i] * (10 ** _decimals));
      }
    }
  }

  function clearStuckBalance(
    uint256 amountPercentage,
    address adr
  ) external onlyTeam {
    uint256 amountETH = address(this).balance;

    if (amountETH > 0) {
      (bool sent, ) = adr.call{value: (amountETH * amountPercentage) / 100}("");
      require(sent, "Failed to transfer funds");
    }
  }

  function blacklistWallets(
    address[] calldata _wallets,
    bool _blacklist
  ) external onlyTeam {
    for (uint i = 0; i < _wallets.length; i++) {
      if (_blacklist) {
        blacklistCount++;
        emit WalletBlacklisted(tx.origin, _wallets[i], block.number);
      } else {
        if (blacklist[_wallets[i]] != 0) blacklistCount--;
      }
      blacklist[_wallets[i]] = _blacklist ? block.number : 0;
    }
  }

  function transfer(
    address recipient,
    uint256 amount
  ) external override returns (bool) {
    return _transferFrom(msg.sender, recipient, amount);
  }

  function transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) external override returns (bool) {
    if (_allowances[sender][msg.sender] != type(uint256).max) {
      _allowances[sender][msg.sender] =
        _allowances[sender][msg.sender] -
        amount;
    }

    return _transferFrom(sender, recipient, amount);
  }

  function _transferFrom(
    address sender,
    address recipient,
    uint256 amount
  ) internal returns (bool) {
    require(sender != address(0), "ERC20: transfer from 0x0");
    require(recipient != address(0), "ERC20: transfer to 0x0");
    require(amount > 0, "Amount must be > zero");
    require(_balances[sender] >= amount, "Insufficient balance");
    if (!launched() && liquidityPools[recipient]) {
      require(isLiquidityCreator[sender], "Liquidity not added yet.");
      launch();
    }
    if (!isTradingEnabled) {
      require(
        isLiquidityCreator[sender] || isLiquidityCreator[recipient],
        "Trading is not launched yet."
      );
    }

    checkTxLimit(sender, recipient, amount);

    if (!liquidityPools[recipient] && recipient != DEAD) {
      if (!isTxLimitExempt[recipient]) {
        checkWalletLimit(recipient, amount);
      }
    }

    if (inSwap) {
      return _basicTransfer(sender, recipient, amount);
    }

    _balances[sender] = _balances[sender] - amount;

    uint256 amountReceived = amount;

    if (shouldTakeFee(sender, recipient)) {
      amountReceived = takeFee(recipient, amount);
      if (shouldSwapBack(recipient) && amount > 0) swapBack(amount);
    }

    _balances[recipient] = _balances[recipient] + amountReceived;

    emit Transfer(sender, recipient, amountReceived);
    return true;
  }

  function launched() internal view returns (bool) {
    return launchBlock != 0;
  }

  function launch() internal {
    launchBlock = block.number;
    launchTimestamp = block.timestamp;
  }

  function openTrading() external onlyTeam {
    require(!isTradingEnabled, "Can't re-open trading");
    isTradingEnabled = true;
    swapEnabled = true;
  }

  function _basicTransfer(
    address sender,
    address recipient,
    uint256 amount
  ) internal returns (bool) {
    _balances[sender] = _balances[sender] - amount;
    _balances[recipient] = _balances[recipient] + amount;
    emit Transfer(sender, recipient, amount);
    return true;
  }

  function checkWalletLimit(address recipient, uint256 amount) internal view {
    uint256 walletLimit = _maxWalletSize;
    require(
      _balances[recipient] + amount <= walletLimit,
      "Amount exceeds the max wallet size."
    );
  }

  function checkTxLimit(
    address sender,
    address recipient,
    uint256 amount
  ) internal view {
    if (isTxLimitExempt[sender] || isTxLimitExempt[recipient]) return;

    require(
      amount <= (liquidityPools[sender] ? _maxBuyTxAmount : _maxSellTxAmount),
      "Amount exceeds the tx limit."
    );

    require(blacklist[sender] == 0, "Wallet blacklisted!");
  }

  function shouldTakeFee(
    address sender,
    address recipient
  ) public view returns (bool) {
    if (!transferTax && !liquidityPools[recipient] && !liquidityPools[sender])
      return false;
    return !isFeeExempt[sender] && !isFeeExempt[recipient];
  }

  function getTotalFee(bool selling) public view returns (uint256) {
    if (selling) return totalSellFee;
    return totalBuyFee;
  }

  function takeFee(
    address recipient,
    uint256 amount
  ) internal returns (uint256) {
    bool selling = liquidityPools[recipient];
    uint256 feeAmount = (amount * getTotalFee(selling)) / feeDenominator;

    _balances[address(this)] += feeAmount;

    return amount - feeAmount;
  }

  function shouldSwapBack(address recipient) internal view returns (bool) {
    return
      !liquidityPools[msg.sender] &&
      !inSwap &&
      swapEnabled &&
      swapBackCounter[block.number] < swapBackRateLimit &&
      liquidityPools[recipient] &&
      _balances[address(this)] >= swapAtMinimum &&
      totalBuyFee + totalSellFee > 0;
  }

  function swapBack(uint256 amount) internal swapping {
    uint256 totalFee = totalBuyFee + totalSellFee;
    uint256 amountToSwap = amount < swapThreshold ? amount : swapThreshold;
    if (_balances[address(this)] < amountToSwap)
      amountToSwap = _balances[address(this)];

    uint256 totalLiquidityFee = liquidityBuyFee + liquiditySellFee;
    uint256 amountToLiquify = ((amountToSwap * totalLiquidityFee) / 2) /
      totalFee;
    amountToSwap -= amountToLiquify;

    address[] memory path = new address[](2);
    path[0] = address(this);
    path[1] = router.WETH();

    uint256 balanceBefore = address(this).balance;

    router.swapExactTokensForETHSupportingFeeOnTransferTokens(
      amountToSwap,
      0,
      path,
      address(this),
      block.timestamp
    );

    uint256 amountETH = address(this).balance - balanceBefore;
    uint256 totalETHFee = totalFee - (totalLiquidityFee / 2);

    uint256 amountETHLiquidity = ((amountETH * totalLiquidityFee) / 2) /
      totalETHFee;
    uint256 amountETHMarketing = amountETH - amountETHLiquidity;

    if (amountETHMarketing > 0) {
      (bool sentMarketing, ) = marketingFeeReceiver.call{
        value: amountETHMarketing
      }("");
      if (!sentMarketing) {
        //Failed to transfer to marketing wallet
      }
    }

    if (amountToLiquify > 0) {
      router.addLiquidityETH{value: amountETHLiquidity}(
        address(this),
        amountToLiquify,
        0,
        0,
        liquidityFeeReceiver,
        block.timestamp
      );
    }
    swapBackCounter[block.number] = swapBackCounter[block.number] + 1;
    emit FundsDistributed(
      amountETHMarketing,
      amountETHLiquidity,
      amountToLiquify
    );
  }

  function addLiquidityPool(address lp, bool isPool) external onlyOwner {
    require(lp != pair, "Can't alter current liquidity pair");
    liquidityPools[lp] = isPool;
  }

  function setSwapBackRateLimit(uint256 rate) external onlyOwner {
    swapBackRateLimit = rate;
  }

  function setTxLimit(
    uint256 buyNumerator,
    uint256 sellNumerator,
    uint256 divisor
  ) external onlyOwner {
    require(
      buyNumerator > 0 && sellNumerator > 0 && divisor > 0 && divisor <= 10000
    );
    _maxBuyTxAmount = (_totalSupply * buyNumerator) / divisor;
    _maxSellTxAmount = (_totalSupply * sellNumerator) / divisor;
  }

  function setMaxWallet(uint256 numerator, uint256 divisor) external onlyOwner {
    require(numerator > 0 && divisor > 0 && divisor <= 10000);
    _maxWalletSize = (_totalSupply * numerator) / divisor;
  }

  function setIsFeeExempt(address holder, bool exempt) external onlyOwner {
    isFeeExempt[holder] = exempt;
  }

  function setIsTxLimitExempt(address holder, bool exempt) external onlyOwner {
    isTxLimitExempt[holder] = exempt;
  }

  function setFees(
    uint256 _liquidityBuyFee,
    uint256 _liquiditySellFee,
    uint256 _marketingBuyFee,
    uint256 _marketingSellFee,
    uint256 _feeDenominator
  ) external onlyOwner {
    require(
      ((_liquidityBuyFee + _liquiditySellFee) / 2) * 2 ==
        (_liquidityBuyFee + _liquiditySellFee),
      "Liquidity fee must be an even number for rounding compatibility."
    );
    liquidityBuyFee = _liquidityBuyFee;
    liquiditySellFee = _liquiditySellFee;
    marketingBuyFee = _marketingBuyFee;
    marketingSellFee = _marketingSellFee;
    totalBuyFee = _liquidityBuyFee + _marketingBuyFee;
    totalSellFee = _liquiditySellFee + _marketingSellFee;
    feeDenominator = _feeDenominator;
    emit FeesSet(totalBuyFee, totalSellFee, feeDenominator);
  }

  function toggleTransferTax() external onlyOwner {
    transferTax = !transferTax;
  }

  function setFeeReceivers(
    address _liquidityFeeReceiver,
    address _marketingFeeReceiver
  ) external onlyOwner {
    liquidityFeeReceiver = payable(_liquidityFeeReceiver);
    marketingFeeReceiver = payable(_marketingFeeReceiver);
  }

  function setSwapBackSettings(
    bool _enabled,
    uint256 _denominator,
    uint256 _swapAtMinimum
  ) external onlyOwner {
    require(_denominator > 0);
    swapEnabled = _enabled;
    swapThreshold = _totalSupply / _denominator;
    swapAtMinimum = _swapAtMinimum * (10 ** _decimals);
  }

  function getCirculatingSupply() public view returns (uint256) {
    return _totalSupply - (balanceOf(DEAD) + balanceOf(ZERO));
  }

  event FundsDistributed(
    uint256 marketingETH,
    uint256 liquidityETH,
    uint256 liquidityTokens
  );
  event FeesSet(
    uint256 totalBuyFees,
    uint256 totalSellFees,
    uint256 denominator
  );
}

// File: contracts/interfaces/IUniswapV2Pair.sol

pragma solidity >=0.5.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}

// File: contracts/interfaces/IUniswapV2ERC20.sol

pragma solidity >=0.5.0;

interface IUniswapV2ERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
}

// File: contracts/libraries/SafeMath.sol

pragma solidity =0.5.16;

// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)

library SafeMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, 'ds-math-add-overflow');
    }

    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, 'ds-math-sub-underflow');
    }

    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
    }
}

// File: contracts/UniswapV2ERC20.sol

pragma solidity =0.5.16;



contract UniswapV2ERC20 is IUniswapV2ERC20 {
    using SafeMath for uint;

    string public constant name = 'Uniswap V2';
    string public constant symbol = 'UNI-V2';
    uint8 public constant decimals = 18;
    uint  public totalSupply;
    mapping(address => uint) public balanceOf;
    mapping(address => mapping(address => uint)) public allowance;

    bytes32 public DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint) public nonces;

    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    constructor() public {
        uint chainId;
        assembly {
            chainId := chainid
        }
        DOMAIN_SEPARATOR = keccak256(
            abi.encode(
                keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                keccak256(bytes(name)),
                keccak256(bytes('1')),
                chainId,
                address(this)
            )
        );
    }

    function _mint(address to, uint value) internal {
        totalSupply = totalSupply.add(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(address(0), to, value);
    }

    function _burn(address from, uint value) internal {
        balanceOf[from] = balanceOf[from].sub(value);
        totalSupply = totalSupply.sub(value);
        emit Transfer(from, address(0), value);
    }

    function _approve(address owner, address spender, uint value) private {
        allowance[owner][spender] = value;
        emit Approval(owner, spender, value);
    }

    function _transfer(address from, address to, uint value) private {
        balanceOf[from] = balanceOf[from].sub(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(from, to, value);
    }

    function approve(address spender, uint value) external returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }

    function transfer(address to, uint value) external returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }

    function transferFrom(address from, address to, uint value) external returns (bool) {
        if (allowance[from][msg.sender] != uint(-1)) {
            allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
        }
        _transfer(from, to, value);
        return true;
    }

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
        require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
        bytes32 digest = keccak256(
            abi.encodePacked(
                '\x19\x01',
                DOMAIN_SEPARATOR,
                keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
            )
        );
        address recoveredAddress = ecrecover(digest, v, r, s);
        require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
        _approve(owner, spender, value);
    }
}

// File: contracts/libraries/Math.sol

pragma solidity =0.5.16;

// a library for performing various math operations

library Math {
    function min(uint x, uint y) internal pure returns (uint z) {
        z = x < y ? x : y;
    }

    // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
    function sqrt(uint y) internal pure returns (uint z) {
        if (y > 3) {
            z = y;
            uint x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
    }
}

// File: contracts/libraries/UQ112x112.sol

pragma solidity =0.5.16;

// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))

// range: [0, 2**112 - 1]
// resolution: 1 / 2**112

library UQ112x112 {
    uint224 constant Q112 = 2**112;

    // encode a uint112 as a UQ112x112
    function encode(uint112 y) internal pure returns (uint224 z) {
        z = uint224(y) * Q112; // never overflows
    }

    // divide a UQ112x112 by a uint112, returning a UQ112x112
    function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
        z = x / uint224(y);
    }
}

// File: contracts/interfaces/IERC20.sol

pragma solidity >=0.5.0;

interface IERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);
}

// File: contracts/interfaces/IUniswapV2Factory.sol

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: contracts/interfaces/IUniswapV2Callee.sol

pragma solidity >=0.5.0;

interface IUniswapV2Callee {
    function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
}

// File: contracts/UniswapV2Pair.sol

pragma solidity =0.5.16;








contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
    using SafeMath  for uint;
    using UQ112x112 for uint224;

    uint public constant MINIMUM_LIQUIDITY = 10**3;
    bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));

    address public factory;
    address public token0;
    address public token1;

    uint112 private reserve0;           // uses single storage slot, accessible via getReserves
    uint112 private reserve1;           // uses single storage slot, accessible via getReserves
    uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves

    uint public price0CumulativeLast;
    uint public price1CumulativeLast;
    uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event

    uint private unlocked = 1;
    modifier lock() {
        require(unlocked == 1, 'UniswapV2: LOCKED');
        unlocked = 0;
        _;
        unlocked = 1;
    }

    function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
        _reserve0 = reserve0;
        _reserve1 = reserve1;
        _blockTimestampLast = blockTimestampLast;
    }

    function _safeTransfer(address token, address to, uint value) private {
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
    }

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    constructor() public {
        factory = msg.sender;
    }

    // called once by the factory at time of deployment
    function initialize(address _token0, address _token1) external {
        require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
        token0 = _token0;
        token1 = _token1;
    }

    // update reserves and, on the first call per block, price accumulators
    function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
        require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
        uint32 blockTimestamp = uint32(block.timestamp % 2**32);
        uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
        if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
            // * never overflows, and + overflow is desired
            price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
            price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
        }
        reserve0 = uint112(balance0);
        reserve1 = uint112(balance1);
        blockTimestampLast = blockTimestamp;
        emit Sync(reserve0, reserve1);
    }

    // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
    function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
        address feeTo = IUniswapV2Factory(factory).feeTo();
        feeOn = feeTo != address(0);
        uint _kLast = kLast; // gas savings
        if (feeOn) {
            if (_kLast != 0) {
                uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
                uint rootKLast = Math.sqrt(_kLast);
                if (rootK > rootKLast) {
                    uint numerator = totalSupply.mul(rootK.sub(rootKLast));
                    uint denominator = rootK.mul(5).add(rootKLast);
                    uint liquidity = numerator / denominator;
                    if (liquidity > 0) _mint(feeTo, liquidity);
                }
            }
        } else if (_kLast != 0) {
            kLast = 0;
        }
    }

    // this low-level function should be called from a contract which performs important safety checks
    function mint(address to) external lock returns (uint liquidity) {
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        uint balance0 = IERC20(token0).balanceOf(address(this));
        uint balance1 = IERC20(token1).balanceOf(address(this));
        uint amount0 = balance0.sub(_reserve0);
        uint amount1 = balance1.sub(_reserve1);

        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
        if (_totalSupply == 0) {
            liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
           _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
        } else {
            liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
        }
        require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
        _mint(to, liquidity);

        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
        emit Mint(msg.sender, amount0, amount1);
    }

    // this low-level function should be called from a contract which performs important safety checks
    function burn(address to) external lock returns (uint amount0, uint amount1) {
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        address _token0 = token0;                                // gas savings
        address _token1 = token1;                                // gas savings
        uint balance0 = IERC20(_token0).balanceOf(address(this));
        uint balance1 = IERC20(_token1).balanceOf(address(this));
        uint liquidity = balanceOf[address(this)];

        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
        amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
        amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
        require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
        _burn(address(this), liquidity);
        _safeTransfer(_token0, to, amount0);
        _safeTransfer(_token1, to, amount1);
        balance0 = IERC20(_token0).balanceOf(address(this));
        balance1 = IERC20(_token1).balanceOf(address(this));

        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
        emit Burn(msg.sender, amount0, amount1, to);
    }

    // this low-level function should be called from a contract which performs important safety checks
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
        require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');

        uint balance0;
        uint balance1;
        { // scope for _token{0,1}, avoids stack too deep errors
        address _token0 = token0;
        address _token1 = token1;
        require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
        if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
        if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
        if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
        balance0 = IERC20(_token0).balanceOf(address(this));
        balance1 = IERC20(_token1).balanceOf(address(this));
        }
        uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
        uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
        require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
        { // scope for reserve{0,1}Adjusted, avoids stack too deep errors
        uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
        uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
        require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
        }

        _update(balance0, balance1, _reserve0, _reserve1);
        emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
    }

    // force balances to match reserves
    function skim(address to) external lock {
        address _token0 = token0; // gas savings
        address _token1 = token1; // gas savings
        _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
        _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
    }

    // force reserves to match balances
    function sync() external lock {
        _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
    }
}

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

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

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

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

pragma solidity ^0.4.18;

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

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

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

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

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

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

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

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

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

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

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

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patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.

  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  You may not convey a covered
work if you are a party to an arrangement with a third party that is
in the business of distributing software, under which you make payment
to the third party based on the extent of your activity of conveying
the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory
patent license (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License.  If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.

  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time.  Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.

  Each version is given a distinguishing version number.  If the
Program specifies that a certain numbered version of the GNU General
Public License "or any later version" applies to it, you have the
option of following the terms and conditions either of that numbered
version or of any later version published by the Free Software
Foundation.  If the Program does not specify a version number of the
GNU General Public License, you may choose any version ever published
by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.

  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.

  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

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

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

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

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

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

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

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

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

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

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

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

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

*/