Gwynethification

src/IUniswapV2Router01.sol

@@ -0,0 +1,95 @@
+pragma solidity >=0.6.2;
+
+interface IUniswapV2Router01 {
+    function factory() external pure returns (address);
+    function WETH() external pure returns (address);
+
+    function addLiquidity(
+        address tokenA,
+        address tokenB,
+        uint amountADesired,
+        uint amountBDesired,
+        uint amountAMin,
+        uint amountBMin,
+        address to,
+        uint deadline
+    ) external returns (uint amountA, uint amountB, uint liquidity);
+    function addLiquidityETH(
+        address token,
+        uint amountTokenDesired,
+        uint amountTokenMin,
+        uint amountETHMin,
+        address to,
+        uint deadline
+    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
+    function removeLiquidity(
+        address tokenA,
+        address tokenB,
+        uint liquidity,
+        uint amountAMin,
+        uint amountBMin,
+        address to,
+        uint deadline
+    ) external returns (uint amountA, uint amountB);
+    function removeLiquidityETH(
+        address token,
+        uint liquidity,
+        uint amountTokenMin,
+        uint amountETHMin,
+        address to,
+        uint deadline
+    ) external returns (uint amountToken, uint amountETH);
+    function removeLiquidityWithPermit(
+        address tokenA,
+        address tokenB,
+        uint liquidity,
+        uint amountAMin,
+        uint amountBMin,
+        address to,
+        uint deadline,
+        bool approveMax, uint8 v, bytes32 r, bytes32 s
+    ) external returns (uint amountA, uint amountB);
+    function removeLiquidityETHWithPermit(
+        address token,
+        uint liquidity,
+        uint amountTokenMin,
+        uint amountETHMin,
+        address to,
+        uint deadline,
+        bool approveMax, uint8 v, bytes32 r, bytes32 s
+    ) external returns (uint amountToken, uint amountETH);
+    function swapExactTokensForTokens(
+        uint amountIn,
+        uint amountOutMin,
+        address[] calldata path,
+        address to,
+        uint deadline
+    ) external returns (uint[] memory amounts);
+    function swapTokensForExactTokens(
+        uint amountOut,
+        uint amountInMax,
+        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);
+    function swapTokensForExactETH(uint amountOut, uint amountInMax, 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 swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
+        external
+        payable
+        returns (uint[] memory amounts);
+
+    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
+    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
+    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
+    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
+    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
+}

src/UniswapPortal.sol

@@ -0,0 +1,45 @@
+pragma solidity ^0.8.20;
+
+import "./IUniswapV2Router01.sol";
+import "./erc20/xERC20.sol";
+
+contract UniswapPortal {
+    IUniswapV2Router01 public uniswapRouter;
+    uint64 public parentChainId;
+    address public pool;
+
+    constructor(
+        IUniswapV2Router01 _uniswapRouter,
+        uint64 _parentChainId,
+        address _pool
+    ) {
+        uniswapRouter = _uniswapRouter;
+        parentChainId = _parentChainId;
+        pool = _pool;
+    }
+
+    function swapExactTokensForTokens(
+        uint amountIn,
+        uint amountOutMin,
+        address[] calldata path,
+        address to,
+        uint deadline
+    ) external returns (uint[] memory amounts) {
+        // Transfer tokens to L1
+        // The user needs to approve this contract for spending (on L2)
+        xERC20(path[0]).xTransferFrom(msg.sender, parentChainId, address(this), amountIn);
+
+        // Do the swap on L1 like normal
+        EVM.xCallOptions(parentChainId);
+        amounts = uniswapRouter.swapExactTokensForTokens(
+            amountIn,
+            amountOutMin,
+            path,
+            to,
+            deadline
+        );
+
+        // Get the tokens from L1 back to the user's L2 account
+        xERC20(path[1]).xTransfer(parentChainId, block.chainid, msg.sender, amounts[1]);
+    }
+}

src/erc20/xERC20.sol

@@ -151,4 +151,19 @@ contract xERC20 is IERC20, GwynethContract {
         emit Transfer(from, to, value);
         return true;
     }
+
+    function xTransferFrom(address from, uint256 chain, address to, uint256 value) public returns (bool) {
+        require(balanceOf[from] >= value, "Insufficient balance");
+        if (from != msg.sender) {
+            require(_allowances[from][msg.sender] >= value, "Allowance exceeded");
+            _allowances[from][msg.sender] -= value;
+        }
+        balanceOf[from] -= value;
+
+        EVM.xCallOptions(chain);
+        this._mint(to, value);
+
+        emit Transfer(from, to, value);
+        return true;
+    }
 }