pragma solidity >=0.5.0;

/**
 * @title IUniswapV2Factory 工厂合约接口
 * @notice 定义Uniswap V2工厂合约的标准接口
 */
interface IUniswapV2Factory {
    /// @notice 创建新交易对时触发的事件
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    /// @notice 协议手续费接收地址
    function feeTo() external view returns (address);
    
    /// @notice 有权设置feeTo的地址  
    function feeToSetter() external view returns (address);

    /// @notice 获取指定代币对的交易对地址
    function getPair(address tokenA, address tokenB) external view returns (address pair);
    
    /// @notice 按索引获取交易对地址
    function allPairs(uint) external view returns (address pair);
    
    /// @notice 获取交易对总数
    function allPairsLength() external view returns (uint);

    /// @notice 创建新的交易对
    function createPair(address tokenA, address tokenB) external returns (address pair);

    /// @notice 设置协议手续费接收地址
    function setFeeTo(address) external;
    
    /// @notice 设置手续费设置者地址
    function setFeeToSetter(address) external;
}