pragma solidity =0.6.6;


interface IBzzExchange {

    function mint(uint256 _amount, uint256 _maxCollateralSpend) external returns (bool success);

    function mintTo(uint256 _amount, uint256 _maxCollateralSpend, address _to) external returns (bool success);

    function redeem(uint256 _amount, uint256 _minCollateralReward) external returns (bool success);
}

interface IERC20 {
    function transfer(address to, uint256 value) external returns (bool);

    function transferFrom(address from, address to, uint256 value) external returns (bool);

    function balanceOf(address account) external view returns (uint256);

    function approve(address spender, uint value) external returns (bool);
}

contract BzzExchangeBot {

    IBzzExchange public immutable bzzExchange;

    IERC20 internal bzz_;
    IERC20 internal dai_;

    uint256 public amount;

    address public owner;

    modifier onlyOwner {
        require(msg.sender == owner);
        _;
    }

    constructor() public {
        // bzz.exchange 0x4F32Ab778e85C4aD0CEad54f8f82F5Ee74d46904
        // dai 0x6B175474E89094C44Da98b954EedeAC495271d0F
        // bzz 0x19062190B1925b5b6689D7073fDfC8c2976EF8Cb
        owner = msg.sender;
        bzzExchange = IBzzExchange(0x4F32Ab778e85C4aD0CEad54f8f82F5Ee74d46904);

        dai_ = IERC20(0x6B175474E89094C44Da98b954EedeAC495271d0F);
        bzz_ = IERC20(0x19062190B1925b5b6689D7073fDfC8c2976EF8Cb);

        dai_.approve(address(0x4F32Ab778e85C4aD0CEad54f8f82F5Ee74d46904), 115792089237316195423570985008687907853269984665640564039457584007913129639935);
        bzz_.approve(address(0x4F32Ab778e85C4aD0CEad54f8f82F5Ee74d46904), 115792089237316195423570985008687907853269984665640564039457584007913129639935);
    }


    receive() external payable {
        amount += msg.value;
    }

    // 买进卖出采用同一个方法，防止其他机器人通过input监控
    function bzzExchangeBuyAndSell(uint256 _amount, uint256 _max, bool _direct) public onlyOwner {
        if (_direct == true) {
            bzzExchange.mintTo(_amount, _max, address(this));
        } else {
            bzzExchange.redeem(_amount, _max);
        }
    }

    function withdrawToken(IERC20 token) public onlyOwner {
        token.transfer(msg.sender, token.balanceOf(address(this)));
    }

    function transferOwnership(address newOwner) onlyOwner public {
        if (newOwner != address(0)) {
            owner = newOwner;
        }
    }

    function withdraw() onlyOwner public {
        msg.sender.transfer(amount);
        amount = 0;
    }
}

{
  "compilationTarget": {
    "contracts/BzzExchange.sol": "BzzExchangeBot"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}