Merge pull request #3 from SocketDotTech/feat/generic-swap-impl

generic swap impl

src/swap/socketSwapImpl/SocketSwapImpl.sol

@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.0;
+
+import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
+import {ERC20} from "solmate/tokens/ERC20.sol";
+import "../SwapImplBase.sol";
+import {SwapFailed} from "../../errors/SocketErrors.sol";
+
+
+/**
+ * @title Socket Swap Implementation
+ * @notice Route implementation with functions to swap tokens via External SwapProvider
+ * Called via SocketGateway if the routeId in the request maps to the routeId of SwapProviderImplementation
+ * @author Socket dot tech.
+ */
+contract SocketSwapImpl is SwapImplBase {
+    /// @notice SafeTransferLib - library for safe and optimised operations on ERC20 tokens
+    using SafeTransferLib for ERC20;
+
+    bytes32 public immutable SwapProviderIdentifier;
+    /// @notice address of SwapProviderAggregator to swap the tokens on Chain
+    address public immutable SWAP_PROVIDER_CONTRACT;
+
+    /// @notice socketGatewayAddress to be initialised via storage variable SwapImplBase
+    /// @dev ensure _SwapProviderAggregator are set properly for the chainId in which the contract is being deployed
+    constructor(
+        address _swapProviderContract,
+        bytes32 _swapProviderIdentifier,
+        address _socketGateway,
+        address _socketDeployFactory
+    ) SwapImplBase(_socketGateway, _socketDeployFactory) {
+        SWAP_PROVIDER_CONTRACT = _swapProviderContract;
+        SwapProviderIdentifier = _swapProviderIdentifier;
+    }
+
+    /**
+     * @notice function to swap tokens on the chain and transfer to receiver address
+     *         via SwapProvider-Middleware-Aggregator
+     * @param fromToken token to be swapped
+     * @param toToken token to which fromToken has to be swapped
+     * @param amount amount of fromToken being swapped
+     * @param receiverAddress address of toToken recipient
+     * @param swapExtraData encoded value of properties in the swapData Struct
+     * @return swapped amount (in toToken Address)
+     */
+    function performAction(
+        address fromToken,
+        address toToken,
+        uint256 amount,
+        address receiverAddress,
+        bytes32 metadata,
+        bytes calldata swapExtraData
+    ) external payable override returns (uint256) {
+        uint256 returnAmount;
+
+        if (fromToken != NATIVE_TOKEN_ADDRESS) {
+            ERC20 token = ERC20(fromToken);
+            token.safeTransferFrom(msg.sender, socketGateway, amount);
+            token.safeApprove(SWAP_PROVIDER_CONTRACT, amount);
+            {
+                // additional data is generated in off-chain using the SwapProvider API which takes in
+                // fromTokenAddress, toTokenAddress, amount, fromAddress, slippage, destReceiver, disableEstimate
+                (bool success, bytes memory result) = SWAP_PROVIDER_CONTRACT.call(
+                    swapExtraData
+                );
+                token.safeApprove(SWAP_PROVIDER_CONTRACT, 0);
+
+                if (!success) {
+                    revert SwapFailed();
+                }
+
+                returnAmount = abi.decode(result, (uint256));
+            }
+        } else {
+            // additional data is generated in off-chain using the SwapProvider API which takes in
+            // fromTokenAddress, toTokenAddress, amount, fromAddress, slippage, destReceiver, disableEstimate
+            (bool success, bytes memory result) = SWAP_PROVIDER_CONTRACT.call{
+                value: amount
+            }(swapExtraData);
+            if (!success) {
+                revert SwapFailed();
+            }
+            returnAmount = abi.decode(result, (uint256));
+        }
+
+        emit SocketSwapTokens(
+            fromToken,
+            toToken,
+            returnAmount,
+            amount,
+            SwapProviderIdentifier,
+            receiverAddress,
+            metadata
+        );
+
+        return returnAmount;
+    }
+
+    /**
+     * @notice function to swapWithIn SocketGateway - swaps tokens on the chain to socketGateway as recipient
+     *         via SwapProvider-Middleware-Aggregator
+     * @param fromToken token to be swapped
+     * @param toToken token to which fromToken has to be swapped
+     * @param amount amount of fromToken being swapped
+     * @param swapExtraData encoded value of properties in the swapData Struct
+     * @return swapped amount (in toToken Address)
+     */
+    function performActionWithIn(
+        address fromToken,
+        address toToken,
+        uint256 amount,
+        bytes32 metadata,
+        bytes calldata swapExtraData
+    ) external payable override returns (uint256, address) {
+        uint256 returnAmount;
+
+        if (fromToken != NATIVE_TOKEN_ADDRESS) {
+            ERC20 token = ERC20(fromToken);
+            token.safeTransferFrom(msg.sender, socketGateway, amount);
+            token.safeApprove(SWAP_PROVIDER_CONTRACT, amount);
+            {
+                // additional data is generated in off-chain using the SwapProvider API which takes in
+                // fromTokenAddress, toTokenAddress, amount, fromAddress, slippage, destReceiver, disableEstimate
+                (bool success, bytes memory result) = SWAP_PROVIDER_CONTRACT.call(
+                    swapExtraData
+                );
+                token.safeApprove(SWAP_PROVIDER_CONTRACT, 0);
+
+                if (!success) {
+                    revert SwapFailed();
+                }
+
+                returnAmount = abi.decode(result, (uint256));
+            }
+        } else {
+            // additional data is generated in off-chain using the SwapProvider API which takes in
+            // fromTokenAddress, toTokenAddress, amount, fromAddress, slippage, destReceiver, disableEstimate
+            (bool success, bytes memory result) = SWAP_PROVIDER_CONTRACT.call{
+                value: amount
+            }(swapExtraData);
+            if (!success) {
+                revert SwapFailed();
+            }
+            returnAmount = abi.decode(result, (uint256));
+        }
+
+        emit SocketSwapTokens(
+            fromToken,
+            toToken,
+            returnAmount,
+            amount,
+            SwapProviderIdentifier,
+            socketGateway,
+            metadata
+        );
+
+        return (returnAmount, toToken);
+    }
+}