pragma solidity ^0.5.0;

import "./IDssProxyActions.sol";

contract DssProxyActionsBase {
    uint256 constant RAY = 10**27;

    // Internal functions

    function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require(y == 0 || (z = x * y) / y == x, "mul-overflow");
    }

    function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x - y) <= x, "sub-overflow");
    }

    function toInt(uint256 x) internal pure returns (int256 y) {
        y = int256(x);
        require(y >= 0, "int-overflow");
    }

    function toRad(uint256 wad) internal pure returns (uint256 rad) {
        rad = mul(wad, 10**27);
    }

    function convertTo18(address gemJoin, uint256 amt)
        internal
        returns (uint256 wad)
    {
        // For those collaterals that have less than 18 decimals precision we need to do the conversion before passing to frob function
        // Adapters will automatically handle the difference of precision
        wad = mul(amt, 10**(18 - GemJoinLike(gemJoin).dec()));
    }

    // Public functions

    function daiJoin_join(address apt, address urn, uint256 wad) public {
        // Gets DAI from the user's wallet
        DaiJoinLike(apt).dai().transferFrom(msg.sender, address(this), wad);
        // Approves adapter to take the DAI amount
        DaiJoinLike(apt).dai().approve(apt, wad);
        // Joins DAI into the vat
        DaiJoinLike(apt).join(urn, wad);
    }

    function _getDrawDart(
        address vat,
        address jug,
        address urn,
        bytes32 ilk,
        uint256 wad
    ) internal returns (int256 dart) {
        // Updates stability fee rate
        uint256 rate = JugLike(jug).drip(ilk);

        // Gets DAI balance of the urn in the vat
        uint256 dai = VatLike(vat).dai(urn);

        // If there was already enough DAI in the vat balance, just exits it without adding more debt
        if (dai < mul(wad, RAY)) {
            // Calculates the needed dart so together with the existing dai in the vat is enough to exit wad amount of DAI tokens
            dart = toInt(sub(mul(wad, RAY), dai) / rate);
            // This is neeeded due lack of precision. It might need to sum an extra dart wei (for the given DAI wad amount)
            dart = mul(uint256(dart), rate) < mul(wad, RAY) ? dart + 1 : dart;
        }
    }

    function _getWipeDart(address vat, uint256 dai, address urn, bytes32 ilk)
        internal
        view
        returns (int256 dart)
    {
        // Gets actual rate from the vat
        (, uint256 rate, , , ) = VatLike(vat).ilks(ilk);
        // Gets actual art value of the urn
        (, uint256 art) = VatLike(vat).urns(ilk, urn);

        // Uses the whole dai balance in the vat to reduce the debt
        dart = toInt(dai / rate);
        // Checks the calculated dart is not higher than urn.art (total debt), otherwise uses its value
        dart = uint256(dart) <= art ? -dart : -toInt(art);
    }

    function _getWipeAllWad(address vat, address usr, address urn, bytes32 ilk)
        internal
        view
        returns (uint256 wad)
    {
        // Gets actual rate from the vat
        (, uint256 rate, , , ) = VatLike(vat).ilks(ilk);
        // Gets actual art value of the urn
        (, uint256 art) = VatLike(vat).urns(ilk, urn);
        // Gets actual dai amount in the urn
        uint256 dai = VatLike(vat).dai(usr);

        uint256 rad = sub(mul(art, rate), dai);
        wad = rad / RAY;

        // If the rad precision has some dust, it will need to request for 1 extra wad wei
        wad = mul(wad, RAY) < rad ? wad + 1 : wad;
    }

    // Public functions

    function transfer(address gem, address dst, uint256 wad) public {
        GemLike(gem).transfer(dst, wad);
    }

    function ethJoin_join(address apt, address urn) public payable {
        // Wraps ETH in WETH
        GemJoinLike(apt).gem().deposit.value(msg.value)();
        // Approves adapter to take the WETH amount
        GemJoinLike(apt).gem().approve(address(apt), msg.value);
        // Joins WETH collateral into the vat
        GemJoinLike(apt).join(urn, msg.value);
    }

    function gemJoin_join(
        address apt,
        address urn,
        uint256 wad,
        bool transferFrom
    ) public {
        // Only executes for tokens that have approval/transferFrom implementation
        if (transferFrom) {
            // Gets token from the user's wallet
            GemJoinLike(apt).gem().transferFrom(msg.sender, address(this), wad);
            // Approves adapter to take the token amount
            GemJoinLike(apt).gem().approve(apt, wad);
        }
        // Joins token collateral into the vat
        GemJoinLike(apt).join(urn, wad);
    }

    function hope(address obj, address usr) public {
        HopeLike(obj).hope(usr);
    }

    function nope(address obj, address usr) public {
        HopeLike(obj).nope(usr);
    }

    function open(address manager, bytes32 ilk, address usr)
        public
        returns (uint256 cdp)
    {
        cdp = ManagerLike(manager).open(ilk, usr);
    }

    function give(address manager, uint256 cdp, address usr) public {
        ManagerLike(manager).give(cdp, usr);
    }

    function giveToProxy(
        address proxyRegistry,
        address manager,
        uint256 cdp,
        address dst
    ) public {
        // Gets actual proxy address
        address proxy = ProxyRegistryLike(proxyRegistry).proxies(dst);
        // Checks if the proxy address already existed and dst address is still the owner
        if (proxy == address(0) || ProxyLike(proxy).owner() != dst) {
            uint256 csize;
            assembly {
                csize := extcodesize(dst)
            }
            // We want to avoid creating a proxy for a contract address that might not be able to handle proxies, then losing the CDP
            require(csize == 0, "Dst-is-a-contract");
            // Creates the proxy for the dst address
            proxy = ProxyRegistryLike(proxyRegistry).build(dst);
        }
        // Transfers CDP to the dst proxy
        give(manager, cdp, proxy);
    }

    function cdpAllow(address manager, uint256 cdp, address usr, uint256 ok)
        public
    {
        ManagerLike(manager).cdpAllow(cdp, usr, ok);
    }

    function urnAllow(address manager, address usr, uint256 ok) public {
        ManagerLike(manager).urnAllow(usr, ok);
    }

    function flux(address manager, uint256 cdp, address dst, uint256 wad)
        public
    {
        ManagerLike(manager).flux(cdp, dst, wad);
    }

    function move(address manager, uint256 cdp, address dst, uint256 rad)
        public
    {
        ManagerLike(manager).move(cdp, dst, rad);
    }

    function frob(address manager, uint256 cdp, int256 dink, int256 dart)
        public
    {
        ManagerLike(manager).frob(cdp, dink, dart);
    }

    function quit(address manager, uint256 cdp, address dst) public {
        ManagerLike(manager).quit(cdp, dst);
    }

    function enter(address manager, address src, uint256 cdp) public {
        ManagerLike(manager).enter(src, cdp);
    }

    function shift(address manager, uint256 cdpSrc, uint256 cdpOrg) public {
        ManagerLike(manager).shift(cdpSrc, cdpOrg);
    }
}