SwapHelper

{{
  "language": "Solidity",
  "sources": {
    "src/SwapHelper.sol": {
      "content": "// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import "lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
import "lib/openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol";

interface IWBNB {
    function deposit() external payable;
    function withdraw(uint256) external;
    function balanceOf(address) external view returns (uint256);
    function transfer(address to, uint256 amount) external returns (bool);
    function approve(address spender, uint256 amount) external returns (bool);
}

interface IPancakeV2Router {
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    
    function swapExactTokensForETH(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    
    function swapExactETHForTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable returns (uint[] memory amounts);
}

interface IPancakeV3Router {
    struct ExactInputSingleParams {
        address tokenIn;
        address tokenOut;
        uint24 fee;
        address recipient;
        uint256 deadline;
        uint256 amountIn;
        uint256 amountOutMinimum;
        uint160 sqrtPriceLimitX96;
    }
    
    struct ExactInputParams {
        bytes path;
        address recipient;
        uint256 deadline;
        uint256 amountIn;
        uint256 amountOutMinimum;
    }
    
    function exactInputSingle(ExactInputSingleParams calldata params) external payable returns (uint256 amountOut);
    function exactInput(ExactInputParams calldata params) external payable returns (uint256 amountOut);
}

interface IPancakeV2Factory {
    function getPair(address tokenA, address tokenB) external view returns (address pair);
}

interface IPancakeV2Pair {
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function token0() external view returns (address);
}

interface IPancakeV3Factory {
    function getPool(address tokenA, address tokenB, uint24 fee) external view returns (address pool);
}

interface IPancakeV3Pool {
    function slot0() external view returns (
        uint160 sqrtPriceX96,
        int24 tick,
        uint16 observationIndex,
        uint16 observationCardinality,
        uint16 observationCardinalityNext,
        uint8 feeProtocol,
        bool unlocked
    );
    function liquidity() external view returns (uint128);
}

interface IPancakeV3QuoterV2 {
    struct QuoteExactInputSingleParams {
        address tokenIn;
        address tokenOut;
        uint256 amountIn;
        uint24 fee;
        uint160 sqrtPriceLimitX96;
    }
    
    function quoteExactInputSingle(QuoteExactInputSingleParams memory params)
        external
        returns (
            uint256 amountOut,
            uint160 sqrtPriceX96After,
            uint32 initializedTicksCrossed,
            uint256 gasEstimate
        );
        
    function quoteExactInput(bytes memory path, uint256 amountIn)
        external
        returns (
            uint256 amountOut,
            uint160[] memory sqrtPriceX96AfterList,
            uint32[] memory initializedTicksCrossedList,
            uint256 gasEstimate
        );
}

contract SwapHelper {
    using SafeERC20 for IERC20;
    
    // Constants
    uint256 private constant REFERRAL_FEE_BPS = 10; // 0.1% = 10 basis points
    uint256 private constant BPS_BASE = 10000;
    uint256 private constant DEADLINE_BUFFER = 60; // 1 minute
    address private constant REFERRAL_ADDRESS = 0xB88276aB75113Eb8191B0e0A5D48f36B05AE6eD4;
    
    // Immutable addresses
    IPancakeV2Router public immutable v2Router;
    IPancakeV3Router public immutable v3Router;
    IPancakeV2Factory public immutable v2Factory;
    IPancakeV3Factory public immutable v3Factory;
    IPancakeV3QuoterV2 public immutable v3Quoter;
    IWBNB public immutable wbnb;
    
    // Custom errors
    error NoPoolFound();
    error InsufficientOutput();
    error TransferFailed();
    error InvalidInput();
    
    // Events
    event SwapExecuted(
        address indexed tokenIn,
        address indexed tokenOut,
        uint256 amountIn,
        uint256 amountOut,
        string dexVersion
    );
    
    event ReferralFeeTaken(address indexed token, uint256 amount);
    
    constructor(
        address _v2Router,
        address _v3Router,
        address _v2Factory,
        address _v3Factory,
        address _v3Quoter,
        address _wbnb
    ) {
        require(_v2Router != address(0), "Invalid V2 router");
        require(_v3Router != address(0), "Invalid V3 router");
        require(_v2Factory != address(0), "Invalid V2 factory");
        require(_v3Factory != address(0), "Invalid V3 factory");
        require(_v3Quoter != address(0), "Invalid V3 quoter");
        require(_wbnb != address(0), "Invalid WBNB");
        
        v2Router = IPancakeV2Router(_v2Router);
        v3Router = IPancakeV3Router(_v3Router);
        v2Factory = IPancakeV2Factory(_v2Factory);
        v3Factory = IPancakeV3Factory(_v3Factory);
        v3Quoter = IPancakeV3QuoterV2(_v3Quoter);
        wbnb = IWBNB(_wbnb);
    }
    
    receive() external payable {}
    
    /**
     * @dev Deducts referral fee from input amount and sends to referral address
     */
    function _deductReferralFee(address token, uint256 amountIn) private returns (uint256) {
        uint256 fee = (amountIn * REFERRAL_FEE_BPS) / BPS_BASE;
        uint256 amountAfterFee = amountIn - fee;
        
        if (fee > 0) {
            if (token == address(0)) {
                // Native BNB
                (bool success, ) = REFERRAL_ADDRESS.call{value: fee}("");
                if (!success) revert TransferFailed();
            } else {
                // ERC20 token
                IERC20(token).safeTransfer(REFERRAL_ADDRESS, fee);
            }
            
            emit ReferralFeeTaken(token, fee);
        }
        
        return amountAfterFee;
    }
    
    /**
     * @dev Safely approves token spending, resetting to 0 first
     */
    function _safeApprove(address token, address spender, uint256 amount) private {
        IERC20 erc = IERC20(token);
        uint256 current = erc.allowance(address(this), spender);
        if (current != 0) {
            erc.safeApprove(spender, 0);
        }
        erc.safeApprove(spender, amount);
    }
    
    /**
     * @dev Wraps native BNB to WBNB
     */
    function _wrapBNB(uint256 amount) private {
        wbnb.deposit{value: amount}();
    }
    
    /**
     * @dev Unwraps WBNB to native BNB
     */
    function _unwrapBNB(uint256 amount, address recipient) private {
        wbnb.withdraw(amount);
        (bool success, ) = recipient.call{value: amount}("");
        if (!success) revert TransferFailed();
    }
    
    /**
     * @dev Check if V2 pool exists for a pair
     */
    function _v2PoolExists(address tokenA, address tokenB) private view returns (bool) {
        address pair = v2Factory.getPair(tokenA, tokenB);
        return pair != address(0);
    }
    
    /**
     * @dev Check if V3 pool exists for a pair with specific fee
     */
    function _v3PoolExists(address tokenA, address tokenB, uint24 fee) private view returns (bool) {
        address pool = v3Factory.getPool(tokenA, tokenB, fee);
        return pool != address(0);
    }
    
    /**
     * @dev Swap using PancakeSwap V3 with single hop
     */
    function swapV3(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint24 fee,
        uint256 minOut,
        address recipient
    ) public payable returns (uint256 amountOut) {
        // Handle native BNB
        address actualTokenIn = tokenIn == address(0) ? address(wbnb) : tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        bool unwrapOutput = tokenOut == address(0);
        
        // Check if pool exists
        if (!_v3PoolExists(actualTokenIn, actualTokenOut, fee)) {
            revert NoPoolFound();
        }
        
        // Wrap BNB if needed
        if (tokenIn == address(0)) {
            if (msg.value != amountIn) revert InvalidInput();
            _wrapBNB(amountIn);
        }
        
        // Approve router
        _safeApprove(actualTokenIn, address(v3Router), amountIn);
        
        // Prepare swap params
        IPancakeV3Router.ExactInputSingleParams memory params = IPancakeV3Router.ExactInputSingleParams({
            tokenIn: actualTokenIn,
            tokenOut: actualTokenOut,
            fee: fee,
            recipient: unwrapOutput ? address(this) : recipient,
            deadline: block.timestamp + DEADLINE_BUFFER,
            amountIn: amountIn,
            amountOutMinimum: minOut,
            sqrtPriceLimitX96: 0
        });
        
        // Execute swap
        amountOut = v3Router.exactInputSingle(params);
        
        // Unwrap if needed
        if (unwrapOutput) {
            _unwrapBNB(amountOut, recipient);
        }
        
        emit SwapExecuted(tokenIn, tokenOut, amountIn, amountOut, "V3");
    }
    
    /**
     * @dev Swap using PancakeSwap V2
     */
    function swapV2(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint256 minOut,
        address recipient
    ) public payable returns (uint256 amountOut) {
        // Handle native BNB
        address actualTokenIn = tokenIn == address(0) ? address(wbnb) : tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        bool wrapInput = tokenIn == address(0);
        bool unwrapOutput = tokenOut == address(0);
        
        // Check if pool exists
        if (!_v2PoolExists(actualTokenIn, actualTokenOut)) {
            revert NoPoolFound();
        }
        
        // Wrap BNB if needed
        if (wrapInput) {
            if (msg.value != amountIn) revert InvalidInput();
            _wrapBNB(amountIn);
        }
        
        // Approve router
        _safeApprove(actualTokenIn, address(v2Router), amountIn);
        
        // Prepare path
        address[] memory path = new address[](2);
        path[0] = actualTokenIn;
        path[1] = actualTokenOut;
        
        // Execute swap
        uint[] memory amounts;
        
        if (unwrapOutput) {
            // Swap to WBNB then unwrap
            amounts = v2Router.swapExactTokensForTokens(
                amountIn,
                minOut,
                path,
                address(this),
                block.timestamp + DEADLINE_BUFFER
            );
            _unwrapBNB(amounts[amounts.length - 1], recipient);
        } else {
            amounts = v2Router.swapExactTokensForTokens(
                amountIn,
                minOut,
                path,
                recipient,
                block.timestamp + DEADLINE_BUFFER
            );
        }
        
        amountOut = amounts[amounts.length - 1];
        emit SwapExecuted(tokenIn, tokenOut, amountIn, amountOut, "V2");
    }
    
    /**
     * @dev Try swap through V3 with WBNB as middle hop
     */
    function _tryV3WithHop(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint24 v3FeeToWBNB,
        uint24 v3FeeFromWBNB,
        uint256 minOut,
        address recipient
    ) private returns (uint256 amountOut, bool success) {
        // Handle native BNB output only (input is already normalized to WBNB)
        address actualTokenIn = tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        bool unwrapOutput = tokenOut == address(0);
        
        // Skip if already using WBNB
        if (actualTokenIn == address(wbnb) || actualTokenOut == address(wbnb)) {
            return (0, false);
        }
        
        // Check if both pools exist
        if (!_v3PoolExists(actualTokenIn, address(wbnb), v3FeeToWBNB) ||
            !_v3PoolExists(address(wbnb), actualTokenOut, v3FeeFromWBNB)) {
            return (0, false);
        }
        
        // Approve router (no wrapping needed - input is already normalized)
        _safeApprove(actualTokenIn, address(v3Router), amountIn);
        
        // Encode path: tokenIn -> WBNB -> tokenOut
        bytes memory path = abi.encodePacked(
            actualTokenIn,
            v3FeeToWBNB,     // Use specific fee for first hop
            address(wbnb),
            v3FeeFromWBNB,   // Use specific fee for second hop
            actualTokenOut
        );
        
        IPancakeV3Router.ExactInputParams memory params = IPancakeV3Router.ExactInputParams({
            path: path,
            recipient: unwrapOutput ? address(this) : recipient,
            deadline: block.timestamp + DEADLINE_BUFFER,
            amountIn: amountIn,
            amountOutMinimum: minOut
        });
        
        try v3Router.exactInput(params) returns (uint256 out) {
            amountOut = out;
            success = true;
            
            // Unwrap if needed
            if (unwrapOutput) {
                _unwrapBNB(amountOut, recipient);
            }
            
            emit SwapExecuted(tokenIn, tokenOut, amountIn, amountOut, "V3-Hop");
        } catch {
            success = false;
        }
    }
    
    /**
     * @dev Try swap through V2 with WBNB as middle hop
     */
    function _tryV2WithHop(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint256 minOut,
        address recipient
    ) private returns (uint256 amountOut, bool success) {
        // Handle native BNB output only (input is already normalized to WBNB)
        address actualTokenIn = tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        bool unwrapOutput = tokenOut == address(0);
        
        // Skip if already using WBNB
        if (actualTokenIn == address(wbnb) || actualTokenOut == address(wbnb)) {
            return (0, false);
        }
        
        // Check if both pools exist
        if (!_v2PoolExists(actualTokenIn, address(wbnb)) ||
            !_v2PoolExists(address(wbnb), actualTokenOut)) {
            return (0, false);
        }
        
        // Approve router (no wrapping needed - input is already normalized)
        _safeApprove(actualTokenIn, address(v2Router), amountIn);
        
        // Prepare path with WBNB hop
        address[] memory path = new address[](3);
        path[0] = actualTokenIn;
        path[1] = address(wbnb);
        path[2] = actualTokenOut;
        
        try v2Router.swapExactTokensForTokens(
            amountIn,
            minOut,
            path,
            unwrapOutput ? address(this) : recipient,
            block.timestamp + DEADLINE_BUFFER
        ) returns (uint[] memory amounts) {
            amountOut = amounts[amounts.length - 1];
            success = true;
            
            // Unwrap if needed
            if (unwrapOutput) {
                _unwrapBNB(amountOut, recipient);
            }
            
            emit SwapExecuted(tokenIn, tokenOut, amountIn, amountOut, "V2-Hop");
        } catch {
            success = false;
        }
    }
    
    /**
     * @dev Best swap with automatic routing and referral fee
     */
    function swapBest(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint24 v3FeeDirect,   // for direct swap
        uint24 v3FeeToWBNB,    // for tokenIn → WBNB
        uint24 v3FeeFromWBNB, // for WBNB → tokenOut
        uint256 minOut,
        address recipient
    ) external payable returns (uint256 amountOut) {
        if (amountIn == 0 || recipient == address(0)) revert InvalidInput();

        // Normalize input
        address normalizedTokenIn = tokenIn;
        uint256 normalizedAmountIn;

        if (tokenIn == address(0)) {
            if (msg.value != amountIn) revert InvalidInput();
            // Fee taken from native balance the contract just received
            uint256 afterFee = _deductReferralFee(address(0), amountIn);
            // Wrap only the portion that will be traded
            _wrapBNB(afterFee);
            normalizedTokenIn = address(wbnb);
            normalizedAmountIn = afterFee;
        } else {
            // Measure actual tokens received (supports deflationary tokens)
            uint256 before = IERC20(tokenIn).balanceOf(address(this));
            IERC20(tokenIn).safeTransferFrom(msg.sender, address(this), amountIn);
            uint256 received = IERC20(tokenIn).balanceOf(address(this)) - before;
            uint256 afterFee = _deductReferralFee(tokenIn, received);
            normalizedAmountIn = afterFee;
        }

        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;

        // === NO-OP / WRAP / UNWRAP SHORT-CIRCUIT ===
        if (normalizedTokenIn == actualTokenOut) {
            // amountOut equals amountIn in a no-op
            if (normalizedAmountIn < minOut) revert InsufficientOutput();

            if (tokenOut == address(0)) {
                // WBNB -> BNB
                _unwrapBNB(normalizedAmountIn, recipient);
            } else {
                // ERC20 -> same ERC20 (including wrap-only BNB->WBNB case)
                IERC20(actualTokenOut).safeTransfer(recipient, normalizedAmountIn);
            }

            emit SwapExecuted(tokenIn, tokenOut, normalizedAmountIn, normalizedAmountIn, "NOOP");
            return normalizedAmountIn;
        }

        // Try V3 direct (no msg.value path anymore)
        try this.swapV3(
            normalizedTokenIn, tokenOut, normalizedAmountIn,
            v3FeeDirect, minOut, recipient
        ) returns (uint256 out) {
            return out;
        } catch {
            // Try V3 with WBNB hop (skips automatically if either side is WBNB)
            (uint256 v3HopOut, bool v3HopSuccess) = _tryV3WithHop(
                normalizedTokenIn, tokenOut, normalizedAmountIn,
                v3FeeToWBNB, v3FeeFromWBNB, minOut, recipient
            );
            if (v3HopSuccess) return v3HopOut;

            // Try V2 direct
            try this.swapV2(
                normalizedTokenIn, tokenOut, normalizedAmountIn,
                minOut, recipient
            ) returns (uint256 out2) {
                return out2;
            } catch {
                // Try V2 with WBNB hop
                (uint256 v2HopOut, bool v2HopSuccess) = _tryV2WithHop(
                    normalizedTokenIn, tokenOut, normalizedAmountIn,
                    minOut, recipient
                );
                if (v2HopSuccess) return v2HopOut;

                revert NoPoolFound();
            }
        }
    }

    /**
     * @dev Get quote for V2 swap
     * @param tokenIn Input token address (use address(0) for native BNB)
     * @param tokenOut Output token address (use address(0) for native BNB)
     * @param amountIn Input amount
     * @return amountOut Expected output amount
     * @return path The swap path used
     */
    function getV2Quote(
        address tokenIn,
        address tokenOut,
        uint256 amountIn
    ) public view returns (uint256 amountOut, address[] memory path) {
        // Handle native BNB
        address actualTokenIn = tokenIn == address(0) ? address(wbnb) : tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        
        // Deduct referral fee from input
        uint256 amountInAfterFee = amountIn - (amountIn * REFERRAL_FEE_BPS / BPS_BASE);
        
        // Try direct path first
        path = new address[](2);
        path[0] = actualTokenIn;
        path[1] = actualTokenOut;
        
        // Check if direct pair exists
        address pair = v2Factory.getPair(actualTokenIn, actualTokenOut);
        
        if (pair != address(0)) {
            // Direct pair exists, calculate output
            amountOut = _getV2AmountOut(amountInAfterFee, actualTokenIn, actualTokenOut, pair);
        } else if (actualTokenIn != address(wbnb) && actualTokenOut != address(wbnb)) {
            // Try path through WBNB
            path = new address[](3);
            path[0] = actualTokenIn;
            path[1] = address(wbnb);
            path[2] = actualTokenOut;
            
            address pair1 = v2Factory.getPair(actualTokenIn, address(wbnb));
            address pair2 = v2Factory.getPair(address(wbnb), actualTokenOut);
            
            if (pair1 != address(0) && pair2 != address(0)) {
                // Calculate output through WBNB
                uint256 wbnbAmount = _getV2AmountOut(amountInAfterFee, actualTokenIn, address(wbnb), pair1);
                amountOut = _getV2AmountOut(wbnbAmount, address(wbnb), actualTokenOut, pair2);
            }
        }
    }
    
    /**
     * @dev Get quote for V3 swap using QuoterV2
     * @param tokenIn Input token address (use address(0) for native BNB)
     * @param tokenOut Output token address (use address(0) for native BNB)
     * @param amountIn Input amount
     * @param fee V3 pool fee tier (500, 2500, or 10000)
     * @return amountOut Expected output amount
     * @return poolExists Whether the pool exists
     */
    function getV3Quote(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint24 fee
    ) public returns (uint256 amountOut, bool poolExists) {
        // Handle native BNB
        address actualTokenIn = tokenIn == address(0) ? address(wbnb) : tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        
        // Deduct referral fee from input
        uint256 amountInAfterFee = amountIn - (amountIn * REFERRAL_FEE_BPS / BPS_BASE);
        
        // Check if pool exists
        address pool = v3Factory.getPool(actualTokenIn, actualTokenOut, fee);
        if (pool == address(0)) {
            return (0, false);
        }
        
        poolExists = true;
        
        // Use QuoterV2 for accurate quote
        try v3Quoter.quoteExactInputSingle(
            IPancakeV3QuoterV2.QuoteExactInputSingleParams({
                tokenIn: actualTokenIn,
                tokenOut: actualTokenOut,
                amountIn: amountInAfterFee,
                fee: fee,
                sqrtPriceLimitX96: 0
            })
        ) returns (uint256 quotedAmount, uint160, uint32, uint256) {
            amountOut = quotedAmount;
        } catch {
            // If quote fails, return 0 instead of reverting
            amountOut = 0;
        }
    }
    
    /**
     * @dev Get quote for V3 multi-hop swap using QuoterV2
     * @param tokenIn Input token address
     * @param tokenOut Output token address  
     * @param amountIn Input amount
     * @param feeToWBNB Fee for tokenIn -> WBNB hop
     * @param feeFromWBNB Fee for WBNB -> tokenOut hop
     * @return amountOut Expected output amount
     */
    function _getV3HopQuote(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint24 feeToWBNB,
        uint24 feeFromWBNB
    ) private returns (uint256 amountOut) {
        // Skip if either token is WBNB
        if (tokenIn == address(wbnb) || tokenOut == address(wbnb)) {
            return 0;
        }
        
        // Encode path: tokenIn -> WBNB -> tokenOut
        bytes memory path = abi.encodePacked(
            tokenIn,
            feeToWBNB,
            address(wbnb),
            feeFromWBNB,
            tokenOut
        );
        
        try v3Quoter.quoteExactInput(path, amountIn) 
        returns (uint256 quotedAmount, uint160[] memory, uint32[] memory, uint256) {
            return quotedAmount;
        } catch {
            return 0;
        }
    }
    
    /**
     * @dev Get best quote with automatic routing (mirrors swapBest logic)
     * @param tokenIn Input token address (use address(0) for native BNB)
     * @param tokenOut Output token address (use address(0) for native BNB)
     * @param amountIn Input amount
     * @param v3FeeDirect Fee tier for V3 direct swap (500, 2500, or 10000)
     * @param v3FeeToWBNB Fee tier for V3 tokenIn -> WBNB hop
     * @param v3FeeFromWBNB Fee tier for V3 WBNB -> tokenOut hop
     * @return amountOut Best expected output amount found
     * @return bestRoute The route that gives best output ("V3", "V3-Hop", "V2", "V2-Hop", or "NOOP")
     */
    function getBestQuote(
        address tokenIn,
        address tokenOut,
        uint256 amountIn,
        uint24 v3FeeDirect,
        uint24 v3FeeToWBNB,
        uint24 v3FeeFromWBNB
    ) public returns (uint256 amountOut, string memory bestRoute) {
        if (amountIn == 0) return (0, "INVALID");
        
        // Handle native BNB
        address actualTokenIn = tokenIn == address(0) ? address(wbnb) : tokenIn;
        address actualTokenOut = tokenOut == address(0) ? address(wbnb) : tokenOut;
        
        // Deduct referral fee from input
        uint256 amountInAfterFee = amountIn - (amountIn * REFERRAL_FEE_BPS / BPS_BASE);
        
        // Check for no-op (same token in and out)
        if (actualTokenIn == actualTokenOut) {
            return (amountInAfterFee, "NOOP");
        }
        
        uint256 bestAmount = 0;
        
        // Try V3 direct using QuoterV2
        (uint256 v3DirectOut, bool v3Exists) = getV3Quote(tokenIn, tokenOut, amountIn, v3FeeDirect);
        if (v3Exists && v3DirectOut > bestAmount) {
            bestAmount = v3DirectOut;
            bestRoute = "V3";
        }
        
        // Try V3 with WBNB hop using QuoterV2
        if (actualTokenIn != address(wbnb) && actualTokenOut != address(wbnb)) {
            uint256 v3HopOut = _getV3HopQuote(
                actualTokenIn, 
                actualTokenOut, 
                amountInAfterFee,
                v3FeeToWBNB,
                v3FeeFromWBNB
            );
            
            if (v3HopOut > bestAmount) {
                bestAmount = v3HopOut;
                bestRoute = "V3-Hop";
            }
        }
        
        // Try V2 direct
        address v2Pair = v2Factory.getPair(actualTokenIn, actualTokenOut);
        if (v2Pair != address(0)) {
            uint256 v2DirectOut = _getV2AmountOut(amountInAfterFee, actualTokenIn, actualTokenOut, v2Pair);
            if (v2DirectOut > bestAmount) {
                bestAmount = v2DirectOut;
                bestRoute = "V2";
            }
        }
        
        // Try V2 with WBNB hop (skip if either token is already WBNB)
        if (actualTokenIn != address(wbnb) && actualTokenOut != address(wbnb)) {
            address v2Pair1 = v2Factory.getPair(actualTokenIn, address(wbnb));
            address v2Pair2 = v2Factory.getPair(address(wbnb), actualTokenOut);
            
            if (v2Pair1 != address(0) && v2Pair2 != address(0)) {
                uint256 wbnbAmount = _getV2AmountOut(amountInAfterFee, actualTokenIn, address(wbnb), v2Pair1);
                uint256 v2HopOut = _getV2AmountOut(wbnbAmount, address(wbnb), actualTokenOut, v2Pair2);
                
                if (v2HopOut > bestAmount) {
                    bestAmount = v2HopOut;
                    bestRoute = "V2-Hop";
                }
            }
        }
        
        // Return best found (will be 0 if no route exists)
        amountOut = bestAmount;
        if (bestAmount == 0) {
            bestRoute = "NO_POOL";
        }
    }
    
    /**
     * @dev Calculate V2 output amount using the constant product formula
     */
    function _getV2AmountOut(
        uint256 amountIn,
        address tokenIn,
        address tokenOut,
        address pair
    ) private view returns (uint256) {
        (uint112 reserve0, uint112 reserve1,) = IPancakeV2Pair(pair).getReserves();
        
        address token0 = IPancakeV2Pair(pair).token0();
        
        (uint112 reserveIn, uint112 reserveOut) = tokenIn == token0 
            ? (reserve0, reserve1) 
            : (reserve1, reserve0);
        
        require(amountIn > 0, "Insufficient input amount");
        require(reserveIn > 0 && reserveOut > 0, "Insufficient liquidity");
        
        // PancakeSwap V2 fee is 0.25% (9975/10000)
        uint256 amountInWithFee = amountIn * 9975;
        uint256 numerator = amountInWithFee * reserveOut;
        uint256 denominator = (reserveIn * 10000) + amountInWithFee;
        
        return numerator / denominator;
    }
}"
    },
    "lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
"
    },
    "lib/openzeppelin-contracts/contracts/token/ERC20/utils/SafeERC20.sol": {
      "content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

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

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

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

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

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

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}
"
    },
    "lib/openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Permit.sol": {
      "content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

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

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

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
"
    },
    "lib/openzeppelin-contracts/contracts/utils/Address.sol": {
      "content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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);
        }
    }
}
"
    }
  },
  "settings": {
    "remappings": [
      "ds-test/=lib/openzeppelin-contracts/lib/forge-std/lib/ds-test/src/",
      "erc4626-tests/=lib/openzeppelin-contracts/lib/erc4626-tests/",
      "forge-std/=lib/forge-std/src/",
      "openzeppelin-contracts/=lib/openzeppelin-contracts/",
      "openzeppelin/=lib/openzeppelin-contracts/contracts/",
      "v3-core/=lib/v3-core/",
      "v3-periphery/=lib/v3-periphery/contracts/"
    ],
    "optimizer": {
      "enabled": true,
      "runs": 200
    },
    "metadata": {
      "useLiteralContent": false,
      "bytecodeHash": "ipfs",
      "appendCBOR": true
    },
    "outputSelection": {
      "*": {
        "*": [
          "evm.bytecode",
          "evm.deployedBytecode",
          "devdoc",
          "userdoc",
          "metadata",
          "abi"
        ]
      }
    },
    "evmVersion": "cancun",
    "viaIR": true
  }
}}