Just Data from Blockchain

// SPDX-License-Identifier: Unlicensed

pragma solidity 0.8.19;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}


abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    constructor() {
        _setOwner(_msgSender());
    }

    function owner() public view virtual returns (address) {
        return _owner;
    }

    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    function renounceOwnership() public virtual onlyOwner {
        _setOwner(address(0));
    }

    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

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);
}

interface IERC20Metadata is IERC20 {

    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}


contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;


    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    function name() public view virtual override returns (string memory) {
        return _name;
    }

    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;

        emit Transfer(sender, recipient, amount);

        _afterTokenTransfer(sender, recipient, amount);
    }

    function _createTotalSupply(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}


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);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
}

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;
    }

}

contract JDB is ERC20, Ownable {

    using SafeMath for uint256;

     IUniswapV2Router02 public uniswapV2Router;
    address public immutable uniswapV2Pair;

    uint256 public liquidityFee = 2; 
    uint256 public marketingFee = 3; 
    uint256 public devFee = 4;
    uint256 public totalFee = liquidityFee.add(marketingFee).add(devFee);
    
    uint256 public swapTokensAtAmount = 100000 * (10**18);

    address payable public marketingWallet = payable(0x7bfaD1a6358872de51298f4752bAea427d12dCc9);
    address payable public devWallet = payable(0x325a7544BB0c46DB9de43fB754BAbbc7f9a9338f);

    mapping (address => bool) private _isExcludedFromFees;
    mapping (address => bool) public automatedMarketMakerPairs;
 
    bool private inSwapAndLiquify;
    bool public swapAndLiquifyEnabled = true;
  
    event SwapAndLiquifyEnabledUpdated(bool enabled);
    event SwapEthForTokens(uint256 amountIn, address[] path);
    event SwapAndLiquify(uint256 tokensIntoLiqudity, uint256 ethReceived);
    event UpdateUniswapV2Router(address indexed newAddress, address indexed oldAddress);
    event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);
    event ExcludeFromFees(address indexed account, bool isExcluded);
    
    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiqudity
    );

    modifier lockTheSwap {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }

    constructor() ERC20("Just Data from Blockchain", "JDB") {
    	IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);

         // Create a uniswap pair for this new token
        address _uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), _uniswapV2Router.WETH());

        uniswapV2Router = _uniswapV2Router;
        uniswapV2Pair = _uniswapV2Pair;


        // exclude from paying fees or having max transaction amount
        excludeFromFees(owner(), true);
        excludeFromFees(marketingWallet, true);
        excludeFromFees(devWallet, true);
        excludeFromFees(address(this), true);

        _setAutomatedMarketMakerPair(_uniswapV2Pair, true);
        
        /*
            internal function  that is only called here,
            and CANNOT be called ever again
        */
        _createTotalSupply(owner(), 100000000 * (10**18));
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal override {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
       
        if(amount == 0) {
            super._transfer(from, to, 0);
            return;
        }

        uint256 contractTokenBalance = balanceOf(address(this));
        bool overMinTokenBalance = contractTokenBalance >= swapTokensAtAmount;

        if (
            !inSwapAndLiquify &&
            overMinTokenBalance &&
            automatedMarketMakerPairs[to] &&
            swapAndLiquifyEnabled
        ) {
            contractTokenBalance = swapTokensAtAmount;
            swapAndLiquify(contractTokenBalance);
        }

         if(!_isExcludedFromFees[from] && !_isExcludedFromFees[to]) {
            uint256 _feeTokens = amount.mul(totalFee).div(100);
            amount = amount.sub(_feeTokens);
            super._transfer(from, address(this), _feeTokens);
            
         }

        super._transfer(from, to, amount);

    }

    function swapAndLiquify(uint256 contractTokenBalance) private lockTheSwap {
        uint256 liquidityTokens = contractTokenBalance.mul(liquidityFee).div(totalFee).div(2);
        uint256 swappableTokens = contractTokenBalance.sub(liquidityTokens);

        swapTokensForEth(swappableTokens);

        uint256 totalEthBalance = address(this).balance;
        uint256 ethForLiquidity = totalEthBalance.mul(liquidityFee).div(totalFee).div(2);

        addLiquidity(liquidityTokens, ethForLiquidity);

        emit SwapAndLiquify(liquidityTokens, ethForLiquidity, swappableTokens);

        uint256 remainingEth = totalEthBalance.sub(ethForLiquidity);
    
        uint256 ethForMarketing = remainingEth.mul(marketingFee).div(marketingFee.add(devFee));
        uint256 ethForDev = remainingEth.sub(ethForMarketing);

        marketingWallet.transfer(ethForMarketing);
        devWallet.transfer(ethForDev);
    }


    function swapTokensForEth(uint256 tokenAmount) private {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();

        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // make the swap
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this), // The contract
            block.timestamp
        );
        
    }


    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // add the liquidity
        uniswapV2Router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            owner(),
            block.timestamp
        );
    }


     function updateUniswapV2Router(address newAddress) public onlyOwner {
        require(newAddress != address(uniswapV2Router), "The router already has that address");
        emit UpdateUniswapV2Router(newAddress, address(uniswapV2Router));
        uniswapV2Router = IUniswapV2Router02(newAddress);
    }

    function setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner {
        require(pair != uniswapV2Pair, "The PancakeSwap pair cannot be removed from automatedMarketMakerPairs");
        _setAutomatedMarketMakerPair(pair, value);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        require(automatedMarketMakerPairs[pair] != value, "Automated market maker pair is already set to that value");
        automatedMarketMakerPairs[pair] = value;
        emit SetAutomatedMarketMakerPair(pair, value);
    }

    // owner can't increase the tax. He can only decrease it.
    event FeesUpdated(uint256 liqFee, uint256 markFee, uint256 devFee);

    function setFees(uint256 _liqFee, uint256 _markFee, uint256 _devFee) public onlyOwner() {
        require(_liqFee.add(_markFee).add(_devFee) <= 9, "tax too high");
        liquidityFee = _liqFee;
        marketingFee = _markFee;
        devFee = _devFee;
        totalFee = _liqFee.add(_markFee).add(_devFee);
        emit FeesUpdated(_liqFee, _markFee, _devFee);
    }

    event WalletsUpdated(address marketingWallet, address devWallet);

    function updateWallets(address payable _markWallet, address payable _devWallet) public onlyOwner {  
        marketingWallet = _markWallet;
        devWallet = _devWallet;
        emit WalletsUpdated(_markWallet, _devWallet);
    }

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        require(_isExcludedFromFees[account] != excluded, "Account is already the value of 'excluded'");
        _isExcludedFromFees[account] = excluded;

        emit ExcludeFromFees(account, excluded);
    }

    function SetSwapTokensAtAmount(uint256 newLimit) external onlyOwner {
        require(newLimit > totalSupply().div(1000));
        swapTokensAtAmount = newLimit;
    }
    
    function isExcludedFromFees(address account) public view returns(bool) {
        return _isExcludedFromFees[account];
    }
    
    function setSwapAndLiquifyEnabled(bool _enabled) public onlyOwner {
        swapAndLiquifyEnabled = _enabled;
        emit SwapAndLiquifyEnabledUpdated(_enabled);
    }

    receive() external payable {

  	}
    
}

{
  "compilationTarget": {
    "JDB.sol": "JDB"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}