/*
Vitalik - 維塔利克 
What's crackin', fam? VitalikDev here!
I just woke up, and I saw that wicked rise of Ethereum(科太币)!
I was like, damn, let's ride the hype train and create a Ethereum(科太币) reward token! 
So, I made this crazy 5% reward token where 3% goes to Ethereum(科太币) Rewards, and 2% goes to marketing. 
I'm hustling to build the website, but if one of you cool cats wants to create a Community TG (Telegram) group, that would be mind-blowingly awesome! 
I've got some tokens reserved for the lucky owner, you know what I'm sayin'?
I'm launching this bad boy right now, so no one snags the idea. 
I'm putting in some serious work on the website, and I'm cookin' up something special. 
Stay tuned for more updates, 'cause we're just getting started!
*/
pragma solidity 0.8.20;
// SPDX-License-Identifier: MIT
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) {
        // Solidity only automatically asserts when dividing by 0
        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;
    }
}

/**
 * ERC20 standard interface.
 */
interface IERC20 {
    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;
    }

    /**
     * Function modifier to require caller to be contract owner
     */
    modifier onlyOwner() {
        require(isOwner(msg.sender), "!OWNER"); _;
    }

    /**
     * Function modifier to require caller to be authorized
     */
    modifier authorized() {
        require(isAuthorized(msg.sender), "!AUTHORIZED"); _;
    }

    /**
     * Authorize address. Owner only
     */
    function authorize(address adr) public onlyOwner {
        authorizations[adr] = true;
    }

    /**
     * Remove address' authorization. Owner only
     */
    function unauthorize(address adr) public onlyOwner {
        authorizations[adr] = false;
    }

    /**
     * Check if address is owner
     */
    function isOwner(address account) public view returns (bool) {
        return account == owner;
    }

    /**
     * Return address' authorization status
     */
    function isAuthorized(address adr) public view returns (bool) {
        return authorizations[adr];
    }

    /**
     * Transfer ownership to new address. Caller must be owner. Leaves old owner authorized
     */
    function transferOwnership(address payable adr) public onlyOwner {
        owner = adr;
        authorizations[adr] = true;
        emit OwnershipTransferred(adr);
    }

    event OwnershipTransferred(address owner);
}

interface IDEXFactory {
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}

interface IDEXRouter {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    )
        external
        returns (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        );

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}

interface IRewardsDividends {
    function setDistributionCriteria(
        uint256 _minPeriod,
        uint256 _minDistribution
    ) external;

    function setShare(address shareholder, uint256 amount) external;

    function deposit() external payable;

    function process(uint256 gas) external;

    function withdraw(address shareholder) external;

    function removeStuckDividends() external;
}

contract RewardsDividends is IRewardsDividends {
    using SafeMath for uint256;
    address _token;

    address public ETHEREUM;

    IDEXRouter router;

    struct Share {
        uint256 amount;
        uint256 totalExcluded;
        uint256 totalRealised;
    }

    address[] shareholders;
    mapping(address => uint256) shareholderIndexes;
    mapping(address => uint256) shareholderClaims;
    mapping(address => Share) public shares;

    uint256 public totalShares;
    uint256 public totalDividends;
    uint256 public totalDistributed;
    uint256 public dividendsPerShare;
    uint256 public dividendsPerShareAccuracyFactor = 10**36;

    uint256 public minPeriod = 60 minutes;
    uint256 public minDistribution = 0;

    uint256 public currentIndex;
    bool initialized;

    modifier initialization() {
        require(!initialized);
        _;
        initialized = true;
    }

    modifier onlyToken() {
        require(msg.sender == _token);
        _;
    }

    constructor() {
        _token = msg.sender;
        router = IDEXRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        ETHEREUM = 0xDC5E9445169C73Cf21e1da0B270e8433caC69959; //Ethereum(科太币)
    }

    receive() external payable {
        deposit();
    }

    function removeStuckDividends() external onlyToken {
        uint256 balance = IERC20(ETHEREUM).balanceOf(address(this));

        IERC20(ETHEREUM).transfer(
            address(msg.sender),
            balance
        );
    }

    function setDistributionCriteria(
        uint256 newMinPeriod,
        uint256 newMinDistribution
    ) external override onlyToken {
        minPeriod = newMinPeriod;
        minDistribution = newMinDistribution;
    }

    function setShare(address shareholder, uint256 amount)
        external
        override
        onlyToken
    {
        if (shares[shareholder].amount > 0) {
            distributeDividend(shareholder);
        }

        if (amount > 0 && shares[shareholder].amount == 0) {
            addShareholder(shareholder);
        } else if (amount == 0 && shares[shareholder].amount > 0) {
            removeShareholder(shareholder);
        }

        totalShares = totalShares.sub(shares[shareholder].amount).add(amount);
        shares[shareholder].amount = amount;
        shares[shareholder].totalExcluded = getCumulativeDividends(
            shares[shareholder].amount
        );
    }

    function deposit() public payable override {
        uint256 balanceBefore = IERC20(ETHEREUM).balanceOf(address(this));

        address[] memory path = new address[](2);
        path[0] = router.WETH();
        path[1] = address(ETHEREUM);

        router.swapExactETHForTokensSupportingFeeOnTransferTokens{
            value: msg.value
        }(0, path, address(this), block.timestamp);

        uint256 amount = IERC20(ETHEREUM).balanceOf(address(this)).sub(
            balanceBefore
        );
        totalDividends = totalDividends.add(amount);
        dividendsPerShare = dividendsPerShare.add(
            dividendsPerShareAccuracyFactor.mul(amount).div(totalShares)
        );
    }

    function process(uint256 gas) external override {
        uint256 shareholderCount = shareholders.length;

        if (shareholderCount == 0) {
            return;
        }

        uint256 iterations = 0;
        uint256 gasUsed = 0;
        uint256 gasLeft = gasleft();

        while (gasUsed < gas && iterations < shareholderCount) {
            if (currentIndex >= shareholderCount) {
                currentIndex = 0;
            }

            if (shouldDistribute(shareholders[currentIndex])) {
                distributeDividend(shareholders[currentIndex]);
            }

            gasUsed = gasUsed.add(gasLeft.sub(gasleft()));
            gasLeft = gasleft();
            currentIndex++;
            iterations++;
        }
    }

    function shouldDistribute(address shareholder) public view returns (bool) {
        return
            shareholderClaims[shareholder] + minPeriod < block.timestamp &&
            getUnpaidEarnings(shareholder) > minDistribution;
    }

    function distributeDividend(address shareholder) internal {
        if (shares[shareholder].amount == 0) {
            return;
        }

        uint256 amount = getUnpaidEarnings(shareholder);
        if (amount > 0) {
            totalDistributed = totalDistributed.add(amount);
            IERC20(ETHEREUM).transfer(shareholder, amount);
            shareholderClaims[shareholder] = block.timestamp;
            shares[shareholder].totalRealised = shares[shareholder]
                .totalRealised
                .add(amount);
            shares[shareholder].totalExcluded = getCumulativeDividends(
                shares[shareholder].amount
            );
        }
    }

    function withdraw(address shareholder) external override onlyToken {
        distributeDividend(shareholder);
    }

    function getUnpaidEarnings(address shareholder)
        public
        view
        returns (uint256)
    {
        if (shares[shareholder].amount == 0) {
            return 0;
        }

        uint256 shareholderTotalDividends = getCumulativeDividends(
            shares[shareholder].amount
        );
        uint256 shareholderTotalExcluded = shares[shareholder].totalExcluded;

        if (shareholderTotalDividends <= shareholderTotalExcluded) {
            return 0;
        }

        return shareholderTotalDividends.sub(shareholderTotalExcluded);
    }

    function getCumulativeDividends(uint256 share)
        internal
        view
        returns (uint256)
    {
        return
            share.mul(dividendsPerShare).div(dividendsPerShareAccuracyFactor);
    }

    function addShareholder(address shareholder) internal {
        shareholderIndexes[shareholder] = shareholders.length;
        shareholders.push(shareholder);
    }

    function removeShareholder(address shareholder) internal {
        shareholders[shareholderIndexes[shareholder]] = shareholders[
            shareholders.length - 1
        ];
        shareholderIndexes[
            shareholders[shareholders.length - 1]
        ] = shareholderIndexes[shareholder];
        shareholders.pop();
    }
}

contract Vitalik is IERC20, Auth {
    using SafeMath for uint256;

    address public ETHEREUM = 0xDC5E9445169C73Cf21e1da0B270e8433caC69959; //Ethereum(科太币) 
    string private constant _name = unicode'Vitalik';
    string private constant _symbol = unicode'維塔利克';
    uint8 private constant _decimals = 9;

    uint256 private _totalSupply = 420690000000000 * (10**_decimals);

    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    mapping(address => uint256) private cooldown;

    address private WETH;
    address DEAD = 0x000000000000000000000000000000000000dEaD;
    address ZERO = 0x0000000000000000000000000000000000000000;

    mapping(address => bool) public isFeeExempt;
    mapping(address => bool) public isTxLimitExempt;
    mapping(address => bool) public isDividendExempt;

    address public lpWallet = msg.sender;

    uint256 public buyFee = 5;
    uint256 public sellFee = 5;

    uint256 public toReflections = 60;
    uint256 public toMarketing = 40;

    uint256 public allocationSum = 100;

    IDEXRouter public router;
    address public pair;
    address public factory;
    address private tokenOwner;
    address public devWallet;

    bool inSwapAndLiquify;
    bool public swapAndLiquifyEnabled = true;
    bool public tradingOpen = false;

    RewardsDividends public rewards;
    uint256 public rewardsGas = 0;

    modifier lockTheSwap() {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }

    uint256 public maxTx = _totalSupply * 3 / 100;
    uint256 public maxWallet = _totalSupply * 3 / 100;
    uint256 public swapThreshold = _totalSupply * 1 / 1000;

    constructor(address _owner) Auth(_owner) {
        devWallet = payable(_owner);

        router = IDEXRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);

        WETH = router.WETH();

        pair = IDEXFactory(router.factory()).createPair(WETH, address(this));

        _allowances[address(this)][address(router)] = type(uint256).max;

        rewards = new RewardsDividends();

        isFeeExempt[_owner] = true;
        isFeeExempt[devWallet] = true;

        isDividendExempt[pair] = true;
        isDividendExempt[address(this)] = true;
        isDividendExempt[DEAD] = true;

        isTxLimitExempt[_owner] = true;
        isTxLimitExempt[pair] = true;
        isTxLimitExempt[DEAD] = true;
        isTxLimitExempt[devWallet] = true;

        _balances[_owner] = _totalSupply;

        emit Transfer(address(0), _owner, _totalSupply);
    }

    receive() external payable {}

    //higher buy and sell tax at Launch
    function enableTrading() external onlyOwner {
        tradingOpen = true;
        buyFee = 20;
        sellFee = 30;
        toReflections = 25;
        toMarketing = 75;
    }

    function changeTotalFees(uint256 newBuyFee, uint256 newSellFee)
        external
        onlyOwner
    {
        buyFee = newBuyFee;
        sellFee = newSellFee;

        require(buyFee <= 10, "too high");
        require(sellFee <= 30, "too high");
    }

    function changeFeeAllocation(uint256 newRewardFee, uint256 newMarketingFee)
        external
        onlyOwner
    {
        toReflections = newRewardFee;
        toMarketing = newMarketingFee;
    }

    function changeTxLimit(uint256 amountPercent) external onlyOwner {
        require(maxTx >= 1, "must be more then 1%"); 
        maxTx = (_totalSupply * amountPercent ) / 100;
    }

    function setWalletLimit(uint256 amountPercent) external onlyOwner {
        require(maxWallet >= 1, "must be more then 1%");
        maxWallet = (_totalSupply * amountPercent ) / 100;
    }

    function changeIsFeeExempt(address holder, bool exempt) external onlyOwner {
        isFeeExempt[holder] = exempt;
    }

    function changeIsTxLimitExempt(address holder, bool exempt)
        external
        onlyOwner
    {
        isTxLimitExempt[holder] = exempt;
    }

    function setDevWallet(address payable newDevWallet) external onlyOwner {
        devWallet = payable(newDevWallet);
    }

    function setOwnerWallet(address payable newOwnerWallet) external onlyOwner {
        tokenOwner = newOwnerWallet;
    }

    function changeSwapBackSettings(
        bool enableSwapBack,
        uint256 newSwapBackLimit
    ) external onlyOwner {
        swapAndLiquifyEnabled = enableSwapBack;
        swapThreshold = newSwapBackLimit;
    }

    function setDistributionCriteria(
        uint256 newMinPeriod,
        uint256 newMinDistribution
    ) external onlyOwner {
        rewards.setDistributionCriteria(newMinPeriod, newMinDistribution);
    }

    function _setIsDividendExempt(address holder, bool exempt) internal {
        require(holder != address(this) && holder != pair);
        isDividendExempt[holder] = exempt;
        if (exempt) {
            rewards.setShare(holder, 0);
        } else {
            rewards.setShare(holder, _balances[holder]);
        }
    }

    function setIsDividendExempt(address holder, bool exempt)
        external
        onlyOwner
    {
        _setIsDividendExempt(holder, exempt);
    }

    function changeRewardsGas(uint256 newGas) external onlyOwner {
        rewardsGas = newGas;
    }

    function getCirculatingSupply() public view returns (uint256) {
        return _totalSupply.sub(balanceOf(DEAD)).sub(balanceOf(ZERO));
    }

    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, type(uint256).max);
    }

    function transfer(address recipient, uint256 amount)
        external
        override
        returns (bool)
    {
        return _transfer(msg.sender, recipient, amount);
    }

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external override returns (bool) {
        if (_allowances[sender][msg.sender] != type(uint256).max) {
            _allowances[sender][msg.sender] = _allowances[sender][msg.sender]
                .sub(amount, "Insufficient Allowance");
        }

        return _transfer(sender, recipient, amount);
    }

    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal returns (bool) {
        if (sender != owner && recipient != owner)
            require(tradingOpen, "hold ur horses big guy."); //transfers disabled before tradingActive

        if (inSwapAndLiquify) {
            return _basicTransfer(sender, recipient, amount);
        }

        require(amount <= maxTx || isTxLimitExempt[sender], "tx");



        if (!isTxLimitExempt[recipient]) {
            require(_balances[recipient].add(amount) <= maxWallet, "wallet");
        }

        if (
            msg.sender != pair &&
            !inSwapAndLiquify &&
            swapAndLiquifyEnabled &&
            _balances[address(this)] >= swapThreshold
        ) {
            swapBack();
        }

        _balances[sender] = _balances[sender].sub(
            amount,
            "Insufficient Balance"
        );

        uint256 finalAmount = !isFeeExempt[sender] && !isFeeExempt[recipient]
            ? takeFee(sender, recipient, amount)
            : amount;
        _balances[recipient] = _balances[recipient].add(finalAmount);

        // Dividend tracker
        if (!isDividendExempt[sender]) {
            try rewards.setShare(sender, _balances[sender]) {} catch {}
        }

        if (!isDividendExempt[recipient]) {
            try rewards.setShare(recipient, _balances[recipient]) {} catch {}
        }

        emit Transfer(sender, recipient, finalAmount);
        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 takeFee(
        address sender,
        address recipient,
        uint256 amount
    ) internal returns (uint256) {
        uint256 feeApplicable = pair == recipient ? sellFee : buyFee;
        uint256 feeAmount = amount.mul(feeApplicable).div(100);

        _balances[address(this)] = _balances[address(this)].add(feeAmount);
        emit Transfer(sender, address(this), feeAmount);

        return amount.sub(feeAmount);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();

        approve(address(this), tokenAmount);

        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0,
            0,
            lpWallet,
            block.timestamp
        );
    }

    function swapBack() internal lockTheSwap {
        swapTokensForEth(_balances[address(this)]);

        uint256 totalEthBalance = address(this).balance;

        uint256 ethForEthereum = totalEthBalance.mul(toReflections).div(100);

        try rewards.deposit{value: ethForEthereum}() {} catch {}

        payable(devWallet).transfer(address(this).balance);
    }

    function manualSwapBack() external onlyOwner {
        swapBack();
    }

    function clearStuckEth() external onlyOwner {
        uint256 contractETHBalance = address(this).balance;
        if (contractETHBalance > 0) {
            payable(devWallet).transfer(contractETHBalance);
        }
    }

    function manualProcessGas(uint256 manualGas) external onlyOwner {
        rewards.process(manualGas);
    }

    function checkPendingReflections(address shareholder)
        external
        view
        returns (uint256)
    {
        return rewards.getUnpaidEarnings(shareholder);
    }

    function withdrawFromRewards() external {
        rewards.withdraw(msg.sender);
    }

    function rescueTokens(address _tokenAddr, address _to, uint _amount) public onlyOwner {
        IERC20(_tokenAddr).transfer(_to, _amount);
    }

    function removeStuckDividends() external onlyOwner {
        rewards.removeStuckDividends();
    }
}