1  pragma solidity >=0.6.0;
  2  pragma experimental ABIEncoderV2;
  3  
  4  import "../../../contracts/finance/OptionsExchange.sol";
  5  import "../../../contracts/interfaces/IERC20.sol";
  6  import "../../../contracts/interfaces/IGovernableLiquidityPool.sol";
  7  import "../../../contracts/interfaces/IOptionsExchange.sol";
  8  
  9  contract PoolTrader {
 10      
 11      IERC20 private erc20;
 12      OptionsExchange private exchange;
 13      IGovernableLiquidityPool private pool;
 14      
 15      address private addr;
 16      address private feed;
 17      uint private volumeBase = 1e18;
 18      string symbol;
 19      
 20      constructor(address _erc20, address _exchange, address _pool, address _feed, string memory _symbol) public {
 21  
 22          erc20 = IERC20(_erc20);
 23          exchange = OptionsExchange(_exchange);
 24          pool = IGovernableLiquidityPool(_pool);
 25          addr = address(this);
 26          feed = _feed;
 27          symbol= _symbol;
 28      }
 29      
 30      function balance() external view returns (uint) {
 31          
 32          return erc20.balanceOf(addr) + exchange.balanceOf(addr);
 33      }
 34      
 35      function approve(address spender, uint value) external {
 36          
 37          erc20.approve(spender, value);
 38      }
 39  
 40      function depositInExchange(uint value) external {
 41  
 42          erc20.approve(address(exchange), value);
 43          exchange.depositTokens(address(this), address(erc20), value);
 44      }
 45  
 46      function writeOptions(
 47          uint volume,
 48          IOptionsExchange.OptionType optType,
 49          uint strike, 
 50          uint maturity
 51      )
 52          public
 53          returns (address _tk)
 54      {
 55          IOptionsExchange.OpenExposureInputs memory oEi;
 56  
 57          oEi.symbols = new string[](1);
 58          oEi.volume = new uint[](1);
 59          oEi.isShort = new bool[](1);
 60          oEi.isCovered = new bool[](1);
 61          oEi.poolAddrs = new address[](1);
 62          oEi.paymentTokens = new address[](1);
 63  
 64  
 65          oEi.symbols[0] = symbol;
 66          oEi.volume[0] = volume * volumeBase;
 67          oEi.isShort[0] = true;
 68          oEi.poolAddrs[0] = address(pool);//poolAddr;
 69          //oEi.isCovered[0] = false; //expoliting default to save gas
 70          //oEi.paymentTokens[0] = address(0); //exploiting default to save gas
 71  
 72  
 73          exchange.openExposure(
 74              oEi,
 75              address(this)
 76          );
 77      }
 78  
 79      function withdrawFromPool() external {
 80  
 81          pool.withdraw(IERC20(address(pool)).balanceOf(address(this)));
 82      }
 83      
 84      function buyFromPool(string calldata symbol, uint price, uint volume)
 85          external
 86          returns (address)
 87      {    
 88          erc20.approve(address(pool), price * volume / volumeBase);
 89          return pool.buy(symbol, price, volume, address(erc20));
 90      }
 91      
 92      function sellToPool(string calldata symbol, uint price, uint volume) external {
 93          
 94          IERC20(exchange.resolveToken(symbol)).approve(address(pool), price * volume / volumeBase);
 95          pool.sell(symbol, price, volume);
 96      }
 97      
 98      function withdrawTokens(uint amount) public {
 99          address[] memory tks = new address[](1);
100          tks[0] = address(erc20);
101  
102          uint[] memory tksAmt = new uint[](1);
103          tksAmt[0] = amount;
104          exchange.withdrawTokens(tks, tksAmt);
105      }
106  }