contract FlashArbitrageController is Ownable {
    using SafeMath for uint256;

    event StrategyAdded(string indexed name, uint256 indexed id, address[] pairs, bool feeOff, address indexed originator);

    struct Strategy {
        string strategyName;
        bool[] token0Out; // An array saying if token 0 should be out in this step
        address[] pairs; // Array of pair addresses
        uint256[] feeOnTransfers; //Array of fee on transfers 1% = 10
        bool cBTCSupport; // Should the algorithm check for cBTC and wrap/unwrap it
                        // Note not checking saves gas
        bool feeOff; // Allows for adding CORE strategies - where there is no fee on the executor
    }

    uint256 public revenueSplitFeeOffStrategy;
    uint256 public revenueSplitFeeOnStrategy;
    uint8 MAX_STEPS_LEN; // This variable is responsible to minimsing risk of gas limit strategies being added
                        // Which would always have 0 gas cost because they could never complete

    address public  distributor;
    IFlashArbitrageExecutor public executor;
    address public cBTC = 0x7b5982dcAB054C377517759d0D2a3a5D02615AB8;
    address public CORE = 0x62359Ed7505Efc61FF1D56fEF82158CcaffA23D7;
    address public wBTC = 0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599;
    bool depreciated; // This contract can be upgraded to a new one
                      // But we don't want people to add new strategies if its depreciated
    Strategy[] public strategies;


    constructor (address _executor, address _distributor)  public  {

        distributor = _distributor; // we dont hard set it because its not live yet
                                    // So can't easily mock it in tests
        executor = IFlashArbitrageExecutor(_executor);
        revenueSplitFeeOffStrategy = 100; // 10%
        revenueSplitFeeOnStrategy = 650; // 65%
        MAX_STEPS_LEN = 20;
    }

    
    /////////////////
    //// ADMIN SETTERS
    //////////////////

    //In case executor needs to be updated
    function setExecutor(address _executor) onlyOwner public {
        executor = IFlashArbitrageExecutor(_executor);
    }

    //In case executor needs to be updated
    function setDistributor(address _distributor) onlyOwner public {
        distributor = _distributor;
    }

    function setMaxStrategySteps(uint8 _maxSteps) onlyOwner public {
        MAX_STEPS_LEN = _maxSteps;
    }

    function setDepreciated(bool _depreciated) onlyOwner public {
        depreciated = _depreciated;
    }

    function setFeeSplit(uint256 _revenueSplitFeeOffStrategy, uint256 _revenueSplitFeeOnStrategy) onlyOwner public {
        // We cap both fee splits to 20% max and 95% max
        // This means people calling feeOff strategies get max 20% revenue
        // And people calling feeOn strategies get max 95%
        require(revenueSplitFeeOffStrategy <= 200, "FA : 20% max fee for feeOff revenue split");
        require(revenueSplitFeeOnStrategy <= 950, "FA : 95% max fee for feeOff revenue split");
        revenueSplitFeeOffStrategy = _revenueSplitFeeOffStrategy;
        revenueSplitFeeOnStrategy = _revenueSplitFeeOnStrategy;
    }


    /////////////////
    //// Views for strategies
    //////////////////
    function getOptimalInput(uint256 strategyPID) public view returns (uint256) {
        Strategy memory currentStrategy = strategies[strategyPID];
        return executor.getOptimalInput(currentStrategy.pairs, currentStrategy.feeOnTransfers, currentStrategy.token0Out);
    }

    // Returns the current profit of strateg if it was executed
    // In return token - this means if you borrow CORE from CORe/cBTC pair
    // This profit would be denominated in cBTC
    // Since thats what you have to return 
    function strategyProfitInReturnToken(uint256 strategyID) public view returns (uint256 profit) {
        Strategy memory currentStrategy = strategies[strategyID];
        return executor.getStrategyProfitInReturnToken(currentStrategy.pairs, currentStrategy.feeOnTransfers, currentStrategy.token0Out);
    }


    // Returns information about the strategy
    function strategyInfo(uint256 strategyPID) public view returns (Strategy memory){
        return strategies[strategyPID];
    }

    function numberOfStrategies() public view returns (uint256) {
        return strategies.length;
    }



    ///////////////////
    //// Strategy execution
    //// And profit assurances
    //////////////////

    // Public function that executes a strategy
    // since its all a flash swap
    // the strategies can't lose money only gain
    // so its appropriate that they are public here
    // I don't think its possible that one of the strategies that is less profitable
    // takes away money from the more profitable one
    // Otherwise people would be able to do it anyway with their own contracts
    function executeStrategy(uint256 strategyPID) public {
        // function executeStrategy(address[] memory pairs, uint256[] memory feeOnTransfers, bool[] memory token0Out, bool cBTCSupport) external;
        require(!depreciated, "This Contract is depreciated");
        Strategy memory currentStrategy = strategies[strategyPID];

        executor.executeStrategy(currentStrategy.pairs, currentStrategy.feeOnTransfers, currentStrategy.token0Out, currentStrategy.cBTCSupport);

        // console.log("Executed Strategy");

        // Eg. Token 0 was out so profit token is token 1
        address profitToken = currentStrategy.token0Out[0] ? 
            IUniswapV2Pair(currentStrategy.pairs[0]).token1() 
                : 
            IUniswapV2Pair(currentStrategy.pairs[0]).token0();

        // console.log("Profit token", profitToken);

        uint256 profit = IERC20(profitToken).balanceOf(address(this));
        // console.log("Profit ", profit);

        // We split the profit based on the strategy
        if(currentStrategy.feeOff) {
            safeTransfer(profitToken, msg.sender, profit.mul(revenueSplitFeeOffStrategy).div(1000));
        }
        else {
            safeTransfer(profitToken, msg.sender, profit.mul(revenueSplitFeeOnStrategy).div(1000));
        }
        // console.log("Send revenue split now have ", IERC20(profitToken).balanceOf(address(this)) );

        safeTransfer(profitToken, distributor, IERC20(profitToken).balanceOf(address(this)));

    }


    ///////////////////
    //// Adding strategies
    //////////////////


    // Normal add without Fee Ontrasnfer being specified
    function addNewStrategy(bool borrowToken0, address[] memory pairs) public returns (uint256 strategyID) {

        uint256[] memory feeOnTransfers = new uint256[](pairs.length);
        strategyID = addNewStrategyWithFeeOnTransferTokens(borrowToken0, pairs, feeOnTransfers);

    }

    //Adding strategy with fee on transfer support
    function addNewStrategyWithFeeOnTransferTokens(bool borrowToken0, address[] memory pairs, uint256[] memory feeOnTransfers) public returns (uint256 strategyID) {
        require(!depreciated, "This Contract is depreciated");
        require(pairs.length <= MAX_STEPS_LEN, "FA Controller - too many steps");
        require(pairs.length == feeOnTransfers.length, "FA Controller: Malformed Input -  pairs and feeontransfers should equal");
        bool[] memory token0Out = new bool[](pairs.length);
        // First token out is the same as borrowTokenOut
        token0Out[0] = borrowToken0;

        address token0 = IUniswapV2Pair(pairs[0]).token0();
        address token1 = IUniswapV2Pair(pairs[0]).token1();
        if(msg.sender != owner()) {
            require(token0 != CORE && token1 != CORE, "FA Controller: CORE strategies can be only added by an admin");
        }        
        
        bool cBTCSupport;
        // We turn on cbtc support if any of the borrow token pair has cbtc
        if(token0 == cBTC || token1 == cBTC) cBTCSupport = true;

        // Establish the first token out
        address lastToken = borrowToken0 ? token0 : token1;
        // console.log("Borrowing Token", lastToken);

       
        string memory strategyName = append(
            SafeERC20Namer.tokenSymbol(lastToken),
            " price too low. In ", 
            SafeERC20Namer.tokenSymbol(token0), "/", 
            SafeERC20Namer.tokenSymbol(token1), " pair");

        // console.log(strategyName);

        // Loop over all other pairs
        for (uint256 i = 1; i < token0Out.length; i++) {

            address token0 = IUniswapV2Pair(pairs[i]).token0();
            address token1 = IUniswapV2Pair(pairs[i]).token1();

            if(msg.sender != owner()) {
                require(token0 != CORE && token1 != CORE, "FA Controller: CORE strategies can be only added by an admin");
            }

            // console.log("Last token is", lastToken);
            // console.log("pair is",pairs[i]);
  
            
            // We turn on cbtc support if any of the pairs have cbts
            if(lastToken == cBTC || lastToken == wBTC){       
                require(token0 == cBTC || token1 == cBTC || token0 == wBTC || token1 == wBTC,
                    "FA Controller: Malformed Input - pair does not contain previous token");

            } else{
                // We check if the token is in the next pair
                // If its not then its a wrong input
                // console.log("Last token", lastToken);
                require(token0 == lastToken || token1 == lastToken, "FA Controller: Malformed Input - pair does not contain previous token");

            }




            // If last token is cBTC
            // And the this pair has wBTC in it
            // Then we should have the last token as wBTC
            if(lastToken == cBTC) {
                // console.log("Flipping here");
                cBTCSupport = true;
                // If last token is cBTC and this pair has wBTC and no cBTC
                // Then we are inputting wBTC after unwrapping
                 if(token0 == wBTC || token1 == wBTC && token0 != cBTC && token1 != cBTC){
                     
                     // The token we take out here is opposite of wbtc
                     // Token 0 is out if wBTC is token1
                     // Because we are inputting wBTC
                     token0Out[i] = wBTC == token1;
                     lastToken = wBTC == token1 ? token0 : token1;
                 }
            }

            // If last token is wBTC
            // And cbtc is in this pair
            // And wbtc isn't in this pair
            // Then we wrapped cBTC
             else if(lastToken == wBTC && token0 == cBTC || token1 == cBTC && token0 != wBTC && token1 != wBTC){
                // explained above with cbtc
                cBTCSupport = true;
                token0Out[i] = cBTC == token1;
                lastToken = cBTC == token1 ? token0 : token1;
                // console.log("Token0 out from last wBTC");
            }
            //Default case with no cBTC support
            else {
                // If token 0 is the token we are inputting, the last one
                // Then we take the opposite here
                token0Out[i] = token1 == lastToken;

                // We take the opposite
                // So if we input token1
                // Then token0 is out
                lastToken = token0 == lastToken ? token1 : token0;
                // console.log("Basic branch last token is ", lastToken);
                // console.log("Basic branch last token1 is ", token1);
                // console.log("Basic branch last token0 is ", token0);

                // console.log("Token0 out from basic branch");

            }
          


        //    console.log("Last token is", lastToken);
        
        }
        
        // address[] memory pairs, uint256[] memory feeOnTransfers, bool[] memory token0Out, bool cBTCSupport
        strategies.push(
            Strategy({
                strategyName : strategyName,
                token0Out : token0Out,
                pairs : pairs,
                feeOnTransfers : feeOnTransfers,
                cBTCSupport : cBTCSupport,
                feeOff : msg.sender == owner()
            })
        );

        strategyID = strategies.length;

        emit StrategyAdded(strategyName, strategyID, pairs, msg.sender == owner(), msg.sender);
    }

  
    ///////////////////
    //// Helper functions
    //////////////////
    function sendETH(address payable to, uint256 amt) internal {
        // console.log("I'm transfering ETH", amt/1e18, to);
        // throw exception on failure
        to.transfer(amt);
    }

    function safeTransfer(address token, address to, uint256 value) internal {
            // bytes4(keccak256(bytes('transfer(address,uint256)')));
            (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
            require(success && (data.length == 0 || abi.decode(data, (bool))), 'FA Controller: TRANSFER_FAILED');
    }

    function getTokenSafeName(address token) public view returns (string memory) {
        return SafeERC20Namer.tokenSymbol(token);
    }

    // A function that lets owner remove any tokens from this addrss
    // note this address shoudn't hold any tokens
    // And if it does that means someting already went wrong or someone send them to this address
    function rescueTokens(address token, uint256 amt) public onlyOwner {
        IERC20(token).transfer(owner(), amt);
    }

    function rescueETH(uint256 amt) public {
        sendETH(0xd5b47B80668840e7164C1D1d81aF8a9d9727B421, amt);
    }

    // appends two strings together
    function append(string memory a, string memory b, string memory c, string memory d, string memory e, string memory f) internal pure returns (string memory) {
        return string(abi.encodePacked(a, b,c,d,e,f));
    }


    ///////////////////
    //// Additional functions
    //////////////////

    // This function is for people who do not want to reveal their strategies
    // Note we can do this function because executor requires this contract to be a caller when doing feeoff stratgies
    function skimToken(address _token) public {
        IERC20 token = IERC20(_token);
        uint256 balToken = token.balanceOf(address(this));
        safeTransfer(_token, msg.sender, balToken.mul(revenueSplitFeeOffStrategy).div(1000));
        safeTransfer(_token, distributor, token.balanceOf(address(this)));
    }


}
function strategyProfitInReturnToken(uint256 strategyID) public view returns (uint256 profit) {
    Strategy memory currentStrategy = strategies[strategyID];
    return executor.getStrategyProfitInReturnToken(currentStrategy.pairs, currentStrategy.feeOnTransfers, currentStrategy.token0Out);
}

// Returns the current profit of strateg if it was executed
// In return token - this means if you borrow CORE from CORe/cBTC pair
// This profit would be denominated in cBTC
// Since thats what you have to return 