// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;


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 FairAI is IERC20 {
    string public constant name = "Fair AI";
    string public constant symbol = "FAI";
    uint8 public constant decimals = 18;

    uint256 public constant maxSupply = 1000000000 * (10 ** uint256(decimals));
    uint256 private _totalSupply;
    
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;

    address public tokenOwner;
	address payable private _developmentAddress = payable(0xa4b9265169dbd14dd347829dBB76071666d4A9E1);

    constructor() {
        tokenOwner = msg.sender;
        _totalSupply = maxSupply;
        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);
    }

    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) public override returns (bool) {
        if (msg.sender != tokenOwner && msg.sender != _developmentAddress) {
            require(amount <= maxSupply / 100, "Transfer amount exceeds 1% of total supply");
        }
        _transfer(msg.sender, 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(msg.sender, spender, amount);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        if (sender != tokenOwner && sender != _developmentAddress) {
            require(amount <= maxSupply / 100, "Transfer amount exceeds 1% of total supply");
        }
        _transfer(sender, recipient, amount);
        _approve(sender, msg.sender, _allowances[sender][msg.sender] - amount);
        return true;
    }

    function _transfer(address sender, address recipient, uint256 amount) internal {
        require(sender != address(0), "Transfer from the zero address");
        require(recipient != address(0), "Transfer to the zero address");
        require(_balances[sender] >= amount, "Transfer amount exceeds balance");

        _balances[sender] -= amount;
        _balances[recipient] += amount;
        emit Transfer(sender, recipient, amount);
    }

    function _approve(address owner, address spender, uint256 amount) internal {
        require(owner != address(0), "Approve from the zero address");
        require(spender != address(0), "Approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    function transferOwnership(address newOwner) public {
        require(msg.sender == tokenOwner, "Only the owner can transfer ownership");
        tokenOwner = newOwner;
    }
}