pragma solidity ^0.7.0; // import files from common directory import { TokenInterface , MemoryInterface } from "../common/interfaces.sol"; import { Stores } from "../common/stores.sol"; import { DSMath } from "../common/math.sol"; interface ICurve { function underlying_coins(int128 tokenId) external view returns (address token); function get_dy(int128 sellTokenId, int128 buyTokenId, uint256 sellTokenAmt) external returns (uint256 buyTokenAmt); function exchange(int128 sellTokenId, int128 buyTokenId, uint256 sellTokenAmt, uint256 minBuyToken) external; } abstract contract CurveHelpers is Stores, DSMath { /** * @dev Return Curve 3pool Swap Address */ function getCurveSwapAddr() internal pure returns (address) { return 0xbEbc44782C7dB0a1A60Cb6fe97d0b483032FF1C7; } /** * @dev Return Curve 3pool Token Address */ function getCurveTokenAddr() internal pure returns (address) { return 0x6c3F90f043a72FA612cbac8115EE7e52BDe6E490; } function convert18ToDec(uint _dec, uint256 _amt) internal pure returns (uint256 amt) { amt = (_amt / 10 ** (18 - _dec)); } function convertTo18(uint _dec, uint256 _amt) internal pure returns (uint256 amt) { amt = mul(_amt, 10 ** (18 - _dec)); } function getTokenI(address token) internal pure returns (int128 i) { if (token == address(0x6B175474E89094C44Da98b954EedeAC495271d0F)) { // DAI Token i = 0; } else if (token == address(0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48)) { // USDC Token i = 1; } else if (token == address(0xdAC17F958D2ee523a2206206994597C13D831ec7)) { // USDT Token i = 2; } else { revert("token-not-found."); } } } abstract contract CurveProtocol is CurveHelpers { event LogSell( address indexed buyToken, address indexed sellToken, uint256 buyAmt, uint256 sellAmt, uint256 getId, uint256 setId ); /** * @dev Sell Stable ERC20_Token. * @param buyAddr buying token address. * @param sellAddr selling token amount. * @param sellAmt selling token amount. * @param unitAmt unit amount of buyAmt/sellAmt with slippage. * @param getId Get token amount at this ID from `InstaMemory` Contract. * @param setId Set token amount at this ID in `InstaMemory` Contract. */ function sell( address buyAddr, address sellAddr, uint sellAmt, uint unitAmt, uint getId, uint setId ) external payable { uint _sellAmt = getUint(getId, sellAmt); ICurve curve = ICurve(getCurveSwapAddr()); TokenInterface _buyToken = TokenInterface(buyAddr); TokenInterface _sellToken = TokenInterface(sellAddr); _sellAmt = _sellAmt == uint(-1) ? _sellToken.balanceOf(address(this)) : _sellAmt; _sellToken.approve(address(curve), _sellAmt); uint _slippageAmt = convert18ToDec(_buyToken.decimals(), wmul(unitAmt, convertTo18(_sellToken.decimals(), _sellAmt))); uint intialBal = _buyToken.balanceOf(address(this)); curve.exchange(getTokenI(sellAddr), getTokenI(buyAddr), _sellAmt, _slippageAmt); uint finalBal = _buyToken.balanceOf(address(this)); uint _buyAmt = sub(finalBal, intialBal); setUint(setId, _buyAmt); emit LogSell(buyAddr, sellAddr, _buyAmt, _sellAmt, getId, setId); } } contract ConnectCurveThreePool is CurveProtocol { string public name = "Curve-3pool-v1.0"; }