contracts/LuxToken.sol

// SPDX-License-Identifier: BSD-3-Clause
pragma solidity ^0.8.20;

/// @title LuxToken - Mintable ERC20 for Lux ecosystem tokens
/// @notice Used for LETH, LBTC, LUSD, and other bridged assets
contract LuxToken {
    string public name;
    string public symbol;
    uint8 public immutable decimals;
    address public owner;

    uint256 public totalSupply;
    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) public allowance;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    modifier onlyOwner() {
        require(msg.sender == owner, "LuxToken: not owner");
        _;
    }

    constructor(string memory _name, string memory _symbol, uint8 _decimals) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        owner = msg.sender;
    }

    function mint(address to, uint256 amount) external onlyOwner {
        totalSupply += amount;
        balanceOf[to] += amount;
        emit Transfer(address(0), to, amount);
    }

    function burn(uint256 amount) external {
        require(balanceOf[msg.sender] >= amount, "LuxToken: insufficient balance");
        balanceOf[msg.sender] -= amount;
        totalSupply -= amount;
        emit Transfer(msg.sender, address(0), amount);
    }

    function approve(address spender, uint256 amount) external returns (bool) {
        allowance[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function transfer(address to, uint256 amount) external returns (bool) {
        return transferFrom(msg.sender, to, amount);
    }

    function transferFrom(address from, address to, uint256 amount) public returns (bool) {
        require(balanceOf[from] >= amount, "LuxToken: insufficient balance");

        if (from != msg.sender && allowance[from][msg.sender] != type(uint256).max) {
            require(allowance[from][msg.sender] >= amount, "LuxToken: insufficient allowance");
            allowance[from][msg.sender] -= amount;
        }

        balanceOf[from] -= amount;
        balanceOf[to] += amount;

        emit Transfer(from, to, amount);
        return true;
    }

    function transferOwnership(address newOwner) external onlyOwner {
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }
}