pragma solidity ^0.5.0;
pragma experimental ABIEncoderV2;


contract ProtocolInterface {

    function deposit(address _user, uint _amount) public;
    function withdraw(address _user, uint _amount) public;
}

interface ERC20 {
    function totalSupply() external view returns (uint supply);
    function balanceOf(address _owner) external view returns (uint balance);
    function transfer(address _to, uint _value) external returns (bool success);
    function transferFrom(address _from, address _to, uint _value) external returns (bool success);
    function approve(address _spender, uint _value) external returns (bool success);
    function allowance(address _owner, address _spender) external view returns (uint remaining);
    function decimals() external view returns(uint digits);
    event Approval(address indexed _owner, address indexed _spender, uint _value);
}

contract CTokenInterface is ERC20 {
    function mint(uint mintAmount) external returns (uint);
    function mint() external payable;
    function redeem(uint redeemTokens) external returns (uint);
    function redeemUnderlying(uint redeemAmount) external returns (uint);
    function borrow(uint borrowAmount) external returns (uint);
    function repayBorrow(uint repayAmount) external returns (uint);
    function repayBorrow() external payable;
    function repayBorrowBehalf(address borrower, uint repayAmount) external returns (uint);
    function repayBorrowBehalf(address borrower) external payable;
    function liquidateBorrow(address borrower, uint repayAmount, address cTokenCollateral) external returns (uint);
    function liquidateBorrow(address borrower, address cTokenCollateral) external payable;

    function exchangeRateCurrent() external returns (uint);
    function supplyRatePerBlock() external returns (uint);
    function borrowRatePerBlock() external returns (uint);
    function totalReserves() external returns (uint);
    function reserveFactorMantissa() external returns (uint);
    function borrowBalanceCurrent(address account) external returns (uint);
    function totalBorrowsCurrent() external returns (uint);
    function getCash() external returns (uint);
    function balanceOfUnderlying(address owner) external returns (uint);
}

contract CarefulMath {
    enum MathError {
        NO_ERROR,
        DIVISION_BY_ZERO,
        INTEGER_OVERFLOW,
        INTEGER_UNDERFLOW
    }

    function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
        if (a == 0) {
            return (MathError.NO_ERROR, 0);
        }

        uint c = a * b;

        if (c / a != b) {
            return (MathError.INTEGER_OVERFLOW, 0);
        } else {
            return (MathError.NO_ERROR, c);
        }
    }

    function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
        if (b == 0) {
            return (MathError.DIVISION_BY_ZERO, 0);
        }

        return (MathError.NO_ERROR, a / b);
    }
}

contract Exponential is CarefulMath {
    uint constant expScale = 1e18;
    uint constant halfExpScale = expScale/2;
    uint constant mantissaOne = expScale;

    struct Exp {
        uint mantissa;
    }

    function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint numerator) = mulUInt(expScale, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }
        return getExp(numerator, divisor.mantissa);
    }

    function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
        (MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return (MathError.NO_ERROR, truncate(fraction));
    }

    function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        (MathError err1, uint rational) = divUInt(scaledNumerator, denom);
        if (err1 != MathError.NO_ERROR) {
            return (err1, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: rational}));
    }

    function truncate(Exp memory exp) pure internal returns (uint) {
        // Note: We are not using careful math here as we're performing a division that cannot fail
        return exp.mantissa / expScale;
    }
}

contract ConstantAddressesMainnet {
    address public constant MAKER_DAI_ADDRESS = 0x89d24A6b4CcB1B6fAA2625fE562bDD9a23260359;
    address public constant IDAI_ADDRESS = 0x14094949152EDDBFcd073717200DA82fEd8dC960;
    address public constant SOLO_MARGIN_ADDRESS = 0x1E0447b19BB6EcFdAe1e4AE1694b0C3659614e4e;
    address public constant CDAI_ADDRESS = 0xF5DCe57282A584D2746FaF1593d3121Fcac444dC;
    address public constant KYBER_ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address public constant MKR_ADDRESS = 0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2;
    address public constant WETH_ADDRESS = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address public constant VOX_ADDRESS = 0x9B0F70Df76165442ca6092939132bBAEA77f2d7A;
    address public constant PETH_ADDRESS = 0xf53AD2c6851052A81B42133467480961B2321C09;
    address public constant TUB_ADDRESS = 0x448a5065aeBB8E423F0896E6c5D525C040f59af3;
    address payable public constant WALLET_ID = 0x322d58b9E75a6918f7e7849AEe0fF09369977e08;
    address public constant LOGGER_ADDRESS = 0xeCf88e1ceC2D2894A0295DB3D86Fe7CE4991E6dF;
    address public constant OTC_ADDRESS = 0x794e6e91555438aFc3ccF1c5076A74F42133d08D;
    address public constant DISCOUNT_ADDRESS = 0x1b14E8D511c9A4395425314f849bD737BAF8208F;

    address public constant KYBER_WRAPPER = 0x8F337bD3b7F2b05d9A8dC8Ac518584e833424893;
    address public constant UNISWAP_WRAPPER = 0x1e30124FDE14533231216D95F7798cD0061e5cf8;
    address public constant ETH2DAI_WRAPPER = 0xd7BBB1777E13b6F535Dec414f575b858ed300baF;
    address public constant OASIS_WRAPPER = 0x9aBE2715D2d99246269b8E17e9D1b620E9bf6558;

    address public constant KYBER_INTERFACE = 0x818E6FECD516Ecc3849DAf6845e3EC868087B755;
    address public constant UNISWAP_FACTORY = 0xc0a47dFe034B400B47bDaD5FecDa2621de6c4d95;
    address public constant FACTORY_ADDRESS = 0x5a15566417e6C1c9546523066500bDDBc53F88C7;
    address public constant PIP_INTERFACE_ADDRESS = 0x729D19f657BD0614b4985Cf1D82531c67569197B;

    address public constant PROXY_REGISTRY_INTERFACE_ADDRESS = 0x4678f0a6958e4D2Bc4F1BAF7Bc52E8F3564f3fE4;
    address public constant GAS_TOKEN_INTERFACE_ADDRESS = 0x0000000000b3F879cb30FE243b4Dfee438691c04;

    address public constant SAVINGS_LOGGER_ADDRESS = 0x89b3635BD2bAD145C6f92E82C9e83f06D5654984;

    address public constant SAVER_EXCHANGE_ADDRESS = 0x6eC6D98e2AF940436348883fAFD5646E9cdE2446;

    // Kovan addresses, not used on mainnet
    address public constant COMPOUND_DAI_ADDRESS = 0x25a01a05C188DaCBCf1D61Af55D4a5B4021F7eeD;
    address public constant STUPID_EXCHANGE = 0x863E41FE88288ebf3fcd91d8Dbb679fb83fdfE17;

    // new MCD contracts
    address public constant MANAGER_ADDRESS = 0x5ef30b9986345249bc32d8928B7ee64DE9435E39;
    address public constant VAT_ADDRESS = 0x35D1b3F3D7966A1DFe207aa4514C12a259A0492B;
    address public constant SPOTTER_ADDRESS = 0x65C79fcB50Ca1594B025960e539eD7A9a6D434A3;
    address public constant PROXY_ACTIONS = 0x82ecD135Dce65Fbc6DbdD0e4237E0AF93FFD5038;

    address public constant JUG_ADDRESS = 0x19c0976f590D67707E62397C87829d896Dc0f1F1;
    address public constant DAI_JOIN_ADDRESS = 0x9759A6Ac90977b93B58547b4A71c78317f391A28;
    address public constant ETH_JOIN_ADDRESS = 0x2F0b23f53734252Bda2277357e97e1517d6B042A;
    address public constant MIGRATION_ACTIONS_PROXY = 0xe4B22D484958E582098A98229A24e8A43801b674;

    address public constant SAI_ADDRESS = 0x89d24A6b4CcB1B6fAA2625fE562bDD9a23260359;
    address public constant DAI_ADDRESS = 0x6B175474E89094C44Da98b954EedeAC495271d0F;

    address payable public constant SCD_MCD_MIGRATION = 0xc73e0383F3Aff3215E6f04B0331D58CeCf0Ab849;

    // Our contracts
    address public constant SUBSCRIPTION_ADDRESS = 0x83152CAA0d344a2Fd428769529e2d490A88f4393;
    address public constant MONITOR_ADDRESS = 0x3F4339816EDEF8D3d3970DB2993e2e0Ec6010760;

    address public constant NEW_CDAI_ADDRESS = 0x5d3a536E4D6DbD6114cc1Ead35777bAB948E3643;
    address public constant NEW_IDAI_ADDRESS = 0x493C57C4763932315A328269E1ADaD09653B9081;

    address public constant ERC20_PROXY_0X = 0x95E6F48254609A6ee006F7D493c8e5fB97094ceF;

}

contract ConstantAddressesKovan {
    address public constant KYBER_ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address public constant WETH_ADDRESS = 0xd0A1E359811322d97991E03f863a0C30C2cF029C;
    address public constant MAKER_DAI_ADDRESS = 0xC4375B7De8af5a38a93548eb8453a498222C4fF2;
    address public constant MKR_ADDRESS = 0xAaF64BFCC32d0F15873a02163e7E500671a4ffcD;
    address public constant VOX_ADDRESS = 0xBb4339c0aB5B1d9f14Bd6e3426444A1e9d86A1d9;
    address public constant PETH_ADDRESS = 0xf4d791139cE033Ad35DB2B2201435fAd668B1b64;
    address public constant TUB_ADDRESS = 0xa71937147b55Deb8a530C7229C442Fd3F31b7db2;
    address public constant LOGGER_ADDRESS = 0x32d0e18f988F952Eb3524aCE762042381a2c39E5;
    address payable public  constant WALLET_ID = 0x54b44C6B18fc0b4A1010B21d524c338D1f8065F6;
    address public constant OTC_ADDRESS = 0x4A6bC4e803c62081ffEbCc8d227B5a87a58f1F8F;
    address public constant COMPOUND_DAI_ADDRESS = 0x25a01a05C188DaCBCf1D61Af55D4a5B4021F7eeD;
    address public constant SOLO_MARGIN_ADDRESS = 0x4EC3570cADaAEE08Ae384779B0f3A45EF85289DE;
    address public constant IDAI_ADDRESS = 0xA1e58F3B1927743393b25f261471E1f2D3D9f0F6;
    address public constant CDAI_ADDRESS = 0xb6b09fBffBa6A5C4631e5F7B2e3Ee183aC259c0d;
    address public constant STUPID_EXCHANGE = 0x863E41FE88288ebf3fcd91d8Dbb679fb83fdfE17;
    address public constant DISCOUNT_ADDRESS = 0x1297c1105FEDf45E0CF6C102934f32C4EB780929;
    address public constant SAI_SAVER_PROXY = 0xADB7c74bCe932fC6C27ddA3Ac2344707d2fBb0E6;

    address public constant KYBER_WRAPPER = 0x68c56FF0E7BBD30AF9Ad68225479449869fC1bA0;
    address public constant UNISWAP_WRAPPER = 0x2A4ee140F05f1Ba9A07A020b07CCFB76CecE4b43;
    address public constant ETH2DAI_WRAPPER = 0x823cde416973a19f98Bb9C96d97F4FE6C9A7238B;
    address public constant OASIS_WRAPPER = 0x0257Ba4876863143bbeDB7847beC583e4deb6fE6;

    address public constant SAVER_EXCHANGE_ADDRESS = 0xACA7d11e3f482418C324aAC8e90AaD0431f692A6;


    address public constant FACTORY_ADDRESS = 0xc72E74E474682680a414b506699bBcA44ab9a930;
    //
    address public constant PIP_INTERFACE_ADDRESS = 0xA944bd4b25C9F186A846fd5668941AA3d3B8425F;
    address public constant PROXY_REGISTRY_INTERFACE_ADDRESS = 0x64A436ae831C1672AE81F674CAb8B6775df3475C;
    address public constant GAS_TOKEN_INTERFACE_ADDRESS = 0x0000000000170CcC93903185bE5A2094C870Df62;
    address public constant KYBER_INTERFACE = 0x692f391bCc85cefCe8C237C01e1f636BbD70EA4D;

    address public constant SAVINGS_LOGGER_ADDRESS = 0x2aa889D809B29c608dA99767837D189dAe12a874;

    // Rinkeby, when no Kovan
    address public constant UNISWAP_FACTORY = 0xf5D915570BC477f9B8D6C0E980aA81757A3AaC36;

    // new MCD contracts
    address public constant MANAGER_ADDRESS = 0x1476483dD8C35F25e568113C5f70249D3976ba21;
    address public constant VAT_ADDRESS = 0xbA987bDB501d131f766fEe8180Da5d81b34b69d9;
    address public constant SPOTTER_ADDRESS = 0x3a042de6413eDB15F2784f2f97cC68C7E9750b2D;

    address public constant JUG_ADDRESS = 0xcbB7718c9F39d05aEEDE1c472ca8Bf804b2f1EaD;
    address public constant DAI_JOIN_ADDRESS = 0x5AA71a3ae1C0bd6ac27A1f28e1415fFFB6F15B8c;
    address public constant ETH_JOIN_ADDRESS = 0x775787933e92b709f2a3C70aa87999696e74A9F8;
    address public constant MIGRATION_ACTIONS_PROXY = 0x433870076aBd08865f0e038dcC4Ac6450e313Bd8;
    address public constant PROXY_ACTIONS = 0xd1D24637b9109B7f61459176EdcfF9Be56283a7B;

    address public constant SAI_ADDRESS = 0xC4375B7De8af5a38a93548eb8453a498222C4fF2;
    address public constant DAI_ADDRESS = 0x4F96Fe3b7A6Cf9725f59d353F723c1bDb64CA6Aa;

    address payable public constant SCD_MCD_MIGRATION = 0x411B2Faa662C8e3E5cF8f01dFdae0aeE482ca7b0;

    // Our contracts
    address public constant SUBSCRIPTION_ADDRESS = 0xFC41f79776061a396635aD0b9dF7a640A05063C1;
    address public constant MONITOR_ADDRESS = 0xfC1Fc0502e90B7A3766f93344E1eDb906F8A75DD;

    // TODO: find out what the
    address public constant NEW_CDAI_ADDRESS = 0xe7bc397DBd069fC7d0109C0636d06888bb50668c;
    address public constant NEW_IDAI_ADDRESS = 0x6c1E2B0f67e00c06c8e2BE7Dc681Ab785163fF4D;
}

contract ConstantAddresses is ConstantAddressesMainnet {
}

contract StupidExchange is ConstantAddresses {

    function getMakerDaiToken(uint _amount) public {
        ERC20(MAKER_DAI_ADDRESS).transfer(msg.sender, _amount);
    }

    function getCompoundDaiToken(uint _amount) public {
        ERC20(COMPOUND_DAI_ADDRESS).transfer(msg.sender, _amount);
    }
}

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    constructor() public {
        owner = msg.sender;
        emit LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        emit LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig));
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, address(this), sig);
        }
    }
}

contract CompoundSavingsProtocol is ProtocolInterface, Exponential, ConstantAddresses, DSAuth {

    CTokenInterface public cDaiContract;
    address public savingsProxy;

    constructor() public {
        cDaiContract = CTokenInterface(NEW_CDAI_ADDRESS);
    }

    function addSavingsProxy(address _savingsProxy) public auth {

        savingsProxy = _savingsProxy;
    }

    function deposit(address _user, uint _amount) public {
        require(msg.sender == _user);
        // get dai from user
        require(ERC20(DAI_ADDRESS).transferFrom(_user, address(this), _amount));

        // mainnet only
        ERC20(DAI_ADDRESS).approve(NEW_CDAI_ADDRESS, uint(-1));

        // mint cDai
        require(cDaiContract.mint(_amount) == 0, "Failed Mint");
        // balance should be equal to cDai minted
        uint cDaiMinted = cDaiContract.balanceOf(address(this));
        // return cDai to user
        cDaiContract.transfer(_user, cDaiMinted);
    }

    function withdraw(address _user, uint _amount) public {
        require(msg.sender == _user);
        // transfer all users balance to this contract
        require(cDaiContract.transferFrom(_user, address(this), ERC20(NEW_CDAI_ADDRESS).balanceOf(_user)));
        // approve cDai to compound contract
        cDaiContract.approve(NEW_CDAI_ADDRESS, uint(-1));
        // get dai from cDai contract
        require(cDaiContract.redeemUnderlying(_amount) == 0, "Reedem Failed");

        // return to user balance we didn't spend
        uint cDaiBalance = cDaiContract.balanceOf(address(this));
        if (cDaiBalance > 0) {
            cDaiContract.transfer(_user, cDaiBalance);
        }
        // return dai we have to user
        ERC20(DAI_ADDRESS).transfer(_user, _amount);
    }
}