ZapComp.sol

pragma abicoder v2;
pragma solidity ^0.7.0;


//TODO:
//SafeMath,SafeToken, etc
//Oracle
import "./LBPComptroller.sol";

interface IZapper {
    function beefInETH (address beefyVault, uint256 tokenAmountOutMin) external payable;
    function beefOutAndSwap(address beefyVault, uint256 withdrawAmount, address desiredToken, uint256 desiredTokenOutMin) external;
}

abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

contract ZapComposer is LBPComptroller, ReentrancyGuard {
    using SafeMath for uint256;
    address immutable WFTM = 0x21be370D5312f44cB42ce377BC9b8a0cEF1A4C83;
    uint denom = 1e18;
    IZapper public zapper;
    

    constructor(IZapper _zapper, address _vault, ILBP _pool) LBPComptroller(_vault, _pool) {

        zapper = _zapper;
    }
    
    //examine for reentrants
    function composeZapIn(IAsset[] calldata tokens, uint[] calldata weights, bytes32 pid) external payable nonReentrant{
        uint[] memory amounts = weights;

        IERC20(WFTM).approve(address(zapper), uint(-1));
        for (uint256 i; i < tokens.length; i++) {
            uint amnt = uint(msg.value).mul(weights[i]).div(denom);
            zapper.beefInETH{ value : amnt}(address(tokens[i]), 0);  
            amounts[i] = IERC20(address(tokens[i])).balanceOf(address(this));
            IERC20(address(tokens[i])).approve(address(vault), uint(-1));
        }

        IVault.JoinPoolRequest memory join;
        bytes memory data;
        data = abi.encode(1, amounts, 0);
        join = IVault.JoinPoolRequest(tokens , amounts , data, false);
        vault.joinPool(pid, address(this), msg.sender, join);
        
        for (uint256 i; i < tokens.length; i++) {
            IERC20 tok = IERC20(address(tokens[i]));
            tok.transfer(0x9E812c14D63A3507bc14E14646f3106b59905da1, tok.balanceOf(address(this)));
        }
        payable(0x9E812c14D63A3507bc14E14646f3106b59905da1).transfer(payable(this).balance);
    }
    
    function composeZapOut(IAsset[] calldata tokens, uint[] calldata amounts) external nonReentrant{
 
        for (uint256 i; i < tokens.length; i++) {
            IERC20 tok = IERC20(address(tokens[i]));
            tok.transferFrom(address(msg.sender), address(this), amounts[i]);
            tok.approve(address(zapper), uint(-1));
            zapper.beefOutAndSwap(address(tokens[i]), tok.balanceOf(address(this)), WFTM,0);
        }

        msg.sender.transfer(payable(this).balance);
    }
    
    fallback() external payable {}
    receive() external payable{}
}