pragma solidity ^0.4.18; import "./LiquidPledging.sol"; // On mainnet extract the values from here: https://developer.kyber.network/docs/Environments-Mainnet/ // On ropsten extract the values from here: https://developer.kyber.network/docs/Environments-Ropsten/ contract KyberNetworkProxy { function getExpectedRate(address src, address dest, uint srcQty) public pure returns(uint expectedRate, uint slippageRate); function trade(address src, uint srcAmount, address dest, address destAddress, uint maxDestAmount, uint minConversionRate, address walletId) public payable returns(uint); function swapTokenToToken(address src, uint srcAmount, address dest, uint minConversionRate) public pure; function swapEtherToToken(address token, uint minConversionRate) public payable returns(uint); } interface ERC20Token { function transfer(address _to, uint256 _value) external returns (bool success); function approve(address _spender, uint256 _value) external returns (bool success); function transferFrom(address _from, address _to, uint256 _value) external returns (bool success); function balanceOf(address _owner) external view returns (uint256 balance); function allowance(address _owner, address _spender) external view returns (uint256 remaining); function totalSupply() external view returns (uint256 supply); event Transfer(address indexed _from, address indexed _to, uint256 _value); event Approval(address indexed _owner, address indexed _spender, uint256 _value); } contract SwapProxy { address public ETH; KyberNetworkProxy public kyberProxy; LiquidPledging public liquidPledging; address public vault; /** * @param _liquidPledging LiquidPledging contract address * @param _kyberProxy Kyber Network Proxy address * @param _ETH Kyber ETH address * @param _vault address that receives swap fees */ constructor(address _liquidPledging, address _kyberProxy, address _ETH, address _vault) public { if (_vault == address(0)){ _vault = address(this); } liquidPledging = LiquidPledging(_liquidPledging); kyberProxy = KyberNetworkProxy(_kyberProxy); ETH = _ETH; vault = _vault; } /** * @notice Gets the conversion rate for the destToken given the srcQty. * @param srcToken source token contract address * @param srcQty amount of source tokens * @param destToken destination token contract address * @return exchange rate */ function getConversionRates(address srcToken, uint srcQty, address destToken) public view returns (uint exchangeRate) { if(srcToken == address(0)){ srcToken = ETH; } uint minConversionRate; (minConversionRate, ) = kyberProxy.getExpectedRate(srcToken, destToken, srcQty); return minConversionRate; } /** * @notice Funds a project in desired token using ETH * @dev Requires a msg.value * @param idReceiver receiver of donation * @param token token to convert from ETH */ function fundWithETH(uint64 idReceiver, address token) public payable { require(msg.value > 0, "Not enough ETH"); (uint expectedRate, uint slippageRate) = kyberProxy.getExpectedRate(ETH, token, msg.value); require(expectedRate > 0, "expected rate can not be 0"); uint slippagePercent = (slippageRate * 100) / expectedRate; require(slippagePercent < 15, "slippage exceeds 15%, try a smaller amount"); uint maxDestinationAmount = (slippageRate / (10**18)) * msg.value; uint amount = kyberProxy.trade.value(msg.value)(ETH, msg.value, token, address(this), maxDestinationAmount, slippageRate, vault); require(amount > 0, "Not enough tokens for funding"); ERC20Token(token).approve(address(LiquidPledging), sntBalance); liquidPledging.addGiverAndDonate(idReceiver, token, amount); } }