pragma solidity ^0.7.4;
// SPDX-License-Identifier: Unlicensed
library SafeMath {
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        return c;
    }
}

interface IUniswapV2ERC20 {
    function totalSupply() external view returns (uint256);
    function decimals() external view returns (uint8);
    function symbol() external view returns (string memory);
    function name() external view returns (string memory);
    function getOwner() external view returns (address);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function allowance(address _owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

abstract contract Auth {
    address internal owner;
    mapping (address => bool) internal authorizations;

    constructor(address _owner) {
        owner = _owner;
        authorizations[_owner] = true;
    }

    modifier onlyOwner() {
        require(isOwner(msg.sender), "!OWNER"); _;
    }

    modifier authorized() {
        require(isAuthorized(msg.sender), "!AUTHORIZED"); _;
    }

    function authorize(address adr) public onlyOwner {
        authorizations[adr] = true;
    }

    function unauthorize(address adr) public onlyOwner {
        authorizations[adr] = false;
    }

    function isOwner(address account) public view returns (bool) {
        return account == owner;
    }

    function isAuthorized(address adr) public view returns (bool) {
        return authorizations[adr];
    }

    function transferOwnership(address payable adr) public onlyOwner {
        owner = adr;
        authorizations[adr] = true;
        emit OwnershipTransferred(adr);
    }

    event OwnershipTransferred(address owner);
}

interface IUniswapFactory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

interface IUniswapRouter {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);

    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

contract GreatDaneInu is IUniswapV2ERC20, Auth {
    using SafeMath for uint256;

    address WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;  //mainnet
    //address WETH = 0xc778417E063141139Fce010982780140Aa0cD5Ab;  //ropsten
    
    address DEAD = 0x000000000000000000000000000000000000dEaD;
    address ZERO = 0x0000000000000000000000000000000000000000;

    string constant _name = "GreatDane inu";
    string constant _symbol = "GDI";
    uint8 constant _decimals = 9;

    uint256 _totalSupply = 1000000000000000 * 10**_decimals;

    mapping (address => uint256) _balances;
    mapping (address => mapping (address => uint256)) _allowances;

    bool public blacklistMode = true;
    mapping (address => bool) public isBlacklisted;


    mapping (address => bool) isFeeExempt;

    uint256 public liquidityFee    = 10;
    uint256 public fundFee   = 20;
    uint256 public marketingDevFee    = 20;
    uint256 public burnFee         = 0;
    uint256 public totalFee        = marketingDevFee + fundFee + liquidityFee + burnFee;
    uint256 public feeDenominator  = 1000;

    uint256 public sellMultiplier  = 1000;

    address public autoLiquidityReceiver;
    address public marketingDevFeeReceiver;
    address public fundFeeReceiver;
    address public burnFeeReceiver;

    IUniswapRouter public router;
    address public pair;

    bool public tradingOpen = false;

    bool public swapEnabled = true;
    uint256 public swapThreshold = _totalSupply * 10 / 10000;
    bool inSwap;
    modifier swapping() { inSwap = true; _; inSwap = false; }

    constructor () Auth(msg.sender) {
        router = IUniswapRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); //mainnet
        pair = IUniswapFactory(router.factory()).createPair(WETH, address(this));
        _allowances[address(this)][address(router)] = uint256(-1);

        isFeeExempt[msg.sender] = true;

        autoLiquidityReceiver = msg.sender;
        marketingDevFeeReceiver = 0x6cC48697f3f9f934ca585271d75b1cA886c89E63;
        fundFeeReceiver = 0xcFdC72FF162f9c0C36Ef720c87E480fDbB7F3c89;
        burnFeeReceiver = DEAD;

        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);
    }

    receive() external payable { }

    function totalSupply() external view override returns (uint256) { return _totalSupply; }
    function decimals() external pure override returns (uint8) { return _decimals; }
    function symbol() external pure override returns (string memory) { return _symbol; }
    function name() external pure override returns (string memory) { return _name; }
    function getOwner() external view override returns (address) { return owner; }
    function balanceOf(address account) public view override returns (uint256) { return _balances[account]; }
    function allowance(address holder, address spender) external view override returns (uint256) { return _allowances[holder][spender]; }

    function approve(address spender, uint256 amount) public override returns (bool) {
        _allowances[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function approveMax(address spender) external returns (bool) {
        return approve(spender, uint256(-1));
    }

    function transfer(address recipient, uint256 amount) external override returns (bool) {
        return _transferFrom(msg.sender, recipient, amount);
    }

    function transferFrom(address sender, address recipient, uint256 amount) external override returns (bool) {
        if(_allowances[sender][msg.sender] != uint256(-1)){
            _allowances[sender][msg.sender] = _allowances[sender][msg.sender].sub(amount, "Insufficient Allowance");
        }

        return _transferFrom(sender, recipient, amount);
    }

    function _transferFrom(address sender, address recipient, uint256 amount) internal returns (bool) {
        if(inSwap){ return _basicTransfer(sender, recipient, amount); }

        if(!authorizations[sender] && !authorizations[recipient]){
            require(tradingOpen,"Trading not open yet");
        }

        // Blacklist
        if(blacklistMode){
            require(!isBlacklisted[sender] && !isBlacklisted[recipient],"Blacklisted");    
        }

        if(shouldSwapBack()){ swapBack(); }

        //Exchange tokens
        _balances[sender] = _balances[sender].sub(amount, "Insufficient Balance");
        uint256 amountReceived = (!shouldTakeFee(sender) || !shouldTakeFee(recipient)) ? amount : takeFee(sender, amount,(recipient == pair));
        _balances[recipient] = _balances[recipient].add(amountReceived);

        emit Transfer(sender, recipient, amountReceived);
        return true;
    }
    
    function _basicTransfer(address sender, address recipient, uint256 amount) internal returns (bool) {
        _balances[sender] = _balances[sender].sub(amount, "Insufficient Balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
        return true;
    }

    function shouldTakeFee(address sender) internal view returns (bool) {
        return !isFeeExempt[sender];
    }

    function takeFee(address sender, uint256 amount, bool isSell) internal returns (uint256) {
        
        uint256 multiplier = isSell ? sellMultiplier : 1000;
        uint256 feeAmount = amount.mul(totalFee).mul(multiplier).div(feeDenominator * 1000);

        uint256 burnTokens = feeAmount.mul(burnFee).div(totalFee);
        uint256 contractTokens = feeAmount.sub(burnTokens);

        _balances[address(this)] = _balances[address(this)].add(contractTokens);
        _balances[burnFeeReceiver] = _balances[burnFeeReceiver].add(burnTokens);
        emit Transfer(sender, address(this), contractTokens);
        
        if(burnTokens > 0){
            emit Transfer(sender, burnFeeReceiver, burnTokens);    
        }

        return amount.sub(feeAmount);
    }

    function shouldSwapBack() internal view returns (bool) {
        return msg.sender != pair
        && !inSwap
        && swapEnabled
        && _balances[address(this)] >= swapThreshold;
    }

    function clearStuckBalance(uint256 amountPercentage) external authorized {
        uint256 amountETH = address(this).balance;
        payable(marketingDevFeeReceiver).transfer(amountETH * amountPercentage / 100);
    }

    function clearStuckBalance_sender(uint256 amountPercentage) external authorized {
        uint256 amountETH = address(this).balance;
        payable(msg.sender).transfer(amountETH * amountPercentage / 100);
    }

    function set_sell_multiplier(uint256 Multiplier) external onlyOwner{
        sellMultiplier = Multiplier;        
    }

    // switch Trading
    function tradingStatus(bool _status) public onlyOwner {
        tradingOpen = _status;
    }

    function swapBack() public swapping {
        uint256 amountToLiquify = swapThreshold.mul(liquidityFee).div(totalFee).div(2);
        uint256 amountToSwap = swapThreshold.sub(amountToLiquify);

        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = WETH;

        uint256 balanceBefore = address(this).balance;

        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            amountToSwap,
            0,
            path,
            address(this),
            block.timestamp
        );

        uint256 amountETH = address(this).balance.sub(balanceBefore);

        uint256 totalETHFee = totalFee.sub(liquidityFee.div(2));
        
        uint256 amountLiquidity = amountETH.mul(liquidityFee).div(totalETHFee).div(2);
        uint256 amountFundReflection = amountETH.mul(fundFee).div(totalETHFee);
        uint256 amountMarketingDev = amountETH.mul(marketingDevFee).div(totalETHFee);
 
        (bool tmpSuccess,) = payable(marketingDevFeeReceiver).call{value: amountMarketingDev, gas: 30000}("");
        (tmpSuccess, )= payable(fundFeeReceiver).call{value: amountFundReflection, gas: 30000}("");
        tmpSuccess = false;

        if(amountToLiquify > 0){
            router.addLiquidityETH{value: amountLiquidity}(
                address(this),
                amountToLiquify,
                0,
                0,
                autoLiquidityReceiver,
                block.timestamp
            );
            emit AutoLiquify(amountLiquidity, amountToLiquify);
        }
    }


    function enable_blacklist(bool _status) public onlyOwner {
        blacklistMode = _status;
    }

    function manage_blacklist(address[] calldata addresses, bool status) public onlyOwner {
        for (uint256 i; i < addresses.length; ++i) {
            isBlacklisted[addresses[i]] = status;
        }
    }


    function setIsFeeExempt(address holder, bool exempt) external authorized {
        isFeeExempt[holder] = exempt;
    }

    function setFees(uint256 _liquidityFee, uint256 _fundFee, uint256 _marketingDevFee, uint256 _burnFee, uint256 _feeDenominator) external authorized {
        liquidityFee = _liquidityFee;
        fundFee = _fundFee;
        marketingDevFee = _marketingDevFee;
    
        burnFee = _burnFee;
        totalFee = _liquidityFee.add(_fundFee).add(_marketingDevFee).add(_burnFee);
        feeDenominator = _feeDenominator;
        require(totalFee < feeDenominator/2, "Fees cannot be more than 50%");
    }

    function setFeeReceivers(address _autoLiquidityReceiver, address _marketingDevFeeReceiver, address _fundFeeReceiver ,address _burnFeeReceiver ) external authorized {
        autoLiquidityReceiver = _autoLiquidityReceiver;
        marketingDevFeeReceiver = _marketingDevFeeReceiver;
        fundFeeReceiver = _fundFeeReceiver;
        burnFeeReceiver = _burnFeeReceiver;
    }

    function setSwapBackSettings(bool _enabled, uint256 _amount) external authorized {
        swapEnabled = _enabled;
        swapThreshold = _amount;
    }

    event AutoLiquify(uint256 amountETH, uint256 amountBOG);
}