Rename WstETHtoStETHSwap to WstETHWrappingSwap

contracts/swap/WstETHWrappingSwap.sol

@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+pragma solidity >=0.6.10 <0.8.0;
+
+import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
+import "../interfaces/IStableSwap.sol";
+import "../interfaces/IWstETH.sol";
+import "../utils/SafeDecimalMath.sol";
+
+contract WstETHWrappingSwap is IStableSwap {
+    using SafeERC20 for IERC20;
+    using SafeDecimalMath for uint256;
+
+    address public immutable wstETH; // Base
+    address public immutable stETH; // Quote
+
+    constructor(address wstETH_) public {
+        wstETH = wstETH_;
+        stETH = IWstETH(wstETH_).stETH();
+    }
+
+    function getQuoteOut(uint256 baseIn) external view override returns (uint256 quoteOut) {
+        quoteOut = IWstETH(wstETH).getStETHByWstETH(baseIn);
+    }
+
+    function getQuoteIn(uint256 baseOut) external view override returns (uint256 quoteIn) {
+        quoteIn = IWstETH(wstETH).getStETHByWstETH(baseOut);
+    }
+
+    function getBaseOut(uint256 quoteIn) external view override returns (uint256 baseOut) {
+        baseOut = IWstETH(wstETH).getWstETHByStETH(quoteIn);
+    }
+
+    function getBaseIn(uint256 quoteOut) external view override returns (uint256 baseIn) {
+        baseIn = IWstETH(wstETH).getWstETHByStETH(quoteOut);
+    }
+
+    function buy(
+        uint256,
+        uint256,
+        address recipient,
+        bytes calldata
+    ) external override returns (uint256 realBaseOut) {
+        uint256 quoteIn = IERC20(stETH).balanceOf(address(this));
+        realBaseOut = IWstETH(wstETH).wrap(quoteIn);
+        IERC20(wstETH).safeTransfer(recipient, realBaseOut);
+    }
+
+    function sell(
+        uint256,
+        uint256,
+        address recipient,
+        bytes calldata
+    ) external override returns (uint256 realQuoteOut) {
+        uint256 baseIn = IERC20(wstETH).balanceOf(address(this));
+        realQuoteOut = IWstETH(wstETH).unwrap(baseIn);
+        IERC20(stETH).safeTransfer(recipient, realQuoteOut);
+    }
+
+    function baseAddress() external view override returns (address) {
+        return wstETH;
+    }
+
+    function quoteAddress() external view override returns (address) {
+        return stETH;
+    }
+
+    function getOraclePrice() external view override returns (uint256) {
+        return IWstETH(wstETH).stEthPerToken();
+    }
+
+    function getCurrentPrice() external view override returns (uint256) {
+        return IWstETH(wstETH).stEthPerToken();
+    }
+
+    function fund() external view override returns (IFundV3) {
+        revert("Not implemented");
+    }
+
+    function baseTranche() external view override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function allBalances() external view override returns (uint256, uint256) {
+        revert("Not implemented");
+    }
+
+    function getCurrentD() external view override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function getCurrentPriceOverOracle() external view override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function getPriceOverOracleIntegral() external view override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function addLiquidity(uint256, address) external override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function removeLiquidity(
+        uint256,
+        uint256,
+        uint256,
+        uint256
+    ) external override returns (uint256, uint256) {
+        revert("Not implemented");
+    }
+
+    function removeLiquidityUnwrap(
+        uint256,
+        uint256,
+        uint256,
+        uint256
+    ) external override returns (uint256, uint256) {
+        revert("Not implemented");
+    }
+
+    function removeBaseLiquidity(uint256, uint256, uint256) external override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function removeQuoteLiquidity(uint256, uint256, uint256) external override returns (uint256) {
+        revert("Not implemented");
+    }
+
+    function removeQuoteLiquidityUnwrap(
+        uint256,
+        uint256,
+        uint256
+    ) external override returns (uint256) {
+        revert("Not implemented");
+    }
+}