WIP: SwapRouter 合约

demo-contract/contracts/wtfswap/SwapRouter.sol

@@ -17,63 +17,137 @@ contract SwapRouter is ISwapRouter {
     function exactInput(
         ExactInputParams calldata params
     ) external payable override returns (uint256 amountOut) {
-        // 用 index 记录当前正在读取的 index
-        uint256 index = 0;
-        // while 循环遍历 indexPath，获取每个 pool 的价格
-        while (index < params.indexPath.length) {
+        uint256 amountIn = params.amountIn;
+
+        for (uint256 i = 0; i < params.indexPath.length; i++) {
             address _pool = poolManager.getPool(
                 params.tokenIn,
                 params.tokenOut,
-                params.indexPath[index]
+                params.indexPath[i]
             );
             IPool pool = IPool(_pool);
-            // TODO 交易
-            bytes memory data;
-            // 交易的钱统一转给本合约，最后都完成之后在 swapCallback 中打给用户
-            pool.swap(msg.sender, true, 12, 12, data);
-            amountOut += 2;
-            index++;
+
+            (uint256 amount0Out, uint256 amount1Out) = pool.getAmountsOut(
+                amountIn
+            );
+            amountOut = params.tokenIn < params.tokenOut
+                ? amount1Out
+                : amount0Out;
+
+            bytes memory data = abi.encode(
+                msg.sender,
+                params.tokenIn,
+                params.tokenOut
+            );
+            pool.swap(
+                msg.sender,
+                params.tokenIn < params.tokenOut,
+                amountIn,
+                amountOut,
+                data
+            );
+
+            amountIn = amountOut; // 为下一次循环准备
         }
     }
 
     // 确定输出的 token 交易
     function exactOutput(
         ExactOutputParams calldata params
-    ) external payable override returns (uint256 amountIn) {}
+    ) external payable override returns (uint256 amountIn) {
+        uint256 amountOut = params.amountOut;
+
+        for (uint256 i = params.indexPath.length; i > 0; i--) {
+            address _pool = poolManager.getPool(
+                params.tokenIn,
+                params.tokenOut,
+                params.indexPath[i - 1]
+            );
+            IPool pool = IPool(_pool);
+
+            (uint256 amount0In, uint256 amount1In) = pool.getAmountsIn(
+                amountOut
+            );
+            amountIn = params.tokenIn < params.tokenOut ? amount0In : amount1In;
+
+            bytes memory data = abi.encode(
+                msg.sender,
+                params.tokenIn,
+                params.tokenOut
+            );
+            pool.swap(
+                msg.sender,
+                params.tokenIn > params.tokenOut,
+                amountIn,
+                amountOut,
+                data
+            );
+
+            amountOut = amountIn; // 为下一次循环准备
+        }
+    }
 
     // 确认输入的 token，估算可以获得多少输出的 token
     function quoteExactInput(
         QuoteExactInputParams memory params
     ) external view override returns (uint256 amountOut) {
-        // 用 index 记录当前正在读取的 index
-        uint256 index = 0;
-        // while 循环遍历 indexPath，获取每个 pool 的价格
-        while (index < params.indexPath.length) {
+        uint256 amountIn = params.amountIn;
+
+        for (uint256 i = 0; i < params.indexPath.length; i++) {
             address _pool = poolManager.getPool(
                 params.tokenIn,
                 params.tokenOut,
-                params.indexPath[index]
+                params.indexPath[i]
             );
             IPool pool = IPool(_pool);
-            uint160 sqrtPriceX96 = pool.sqrtPriceX96();
-            // TODO 计算 amountOut
-            amountOut = sqrtPriceX96;
-            // 更新 index
-            index++;
+
+            (uint256 amount0Out, uint256 amount1Out) = pool.getAmountsOut(
+                amountIn
+            );
+            amountOut = params.tokenIn < params.tokenOut
+                ? amount1Out
+                : amount0Out;
+
+            amountIn = amountOut; // 为下一次循环准备
         }
     }
 
     // 确认输出的 token，估算需要多少输入的 token
     function quoteExactOutput(
         QuoteExactOutputParams memory params
-    ) external view override returns (uint256 amountIn) {}
+    ) external view override returns (uint256 amountIn) {
+        uint256 amountOut = params.amountOut;
+
+        for (uint256 i = params.indexPath.length; i > 0; i--) {
+            address _pool = poolManager.getPool(
+                params.tokenIn,
+                params.tokenOut,
+                params.indexPath[i - 1]
+            );
+            IPool pool = IPool(_pool);
+
+            (uint256 amount0In, uint256 amount1In) = pool.getAmountsIn(
+                amountOut
+            );
+            amountIn = params.tokenIn < params.tokenOut ? amount0In : amount1In;
+
+            amountOut = amountIn; // 为下一次循环准备
+        }
+    }
 
     function swapCallback(
         uint256 amount0In,
         uint256 amount1In,
         bytes calldata data
     ) external override {
-        // 每次 swap 后 pool 会调用这个方法
-        // 最后一次 swap 完成后这里统一把钱打给用户
+        (address sender, address tokenIn, address tokenOut) = abi.decode(
+            data,
+            (address, address, address)
+        );
+        uint256 amountIn = tokenIn < tokenOut ? amount0In : amount1In;
+        require(
+            IERC20(tokenIn).transferFrom(sender, msg.sender, amountIn),
+            "Transfer failed"
+        );
     }
 }