import logging

import pymysql
import pymysql.cursors


class MySQLHelper:
    def __init__(self, host, username, password, database, **kwargs):
        """
        初始化 MySQLHelper 实例。

        :param host: 数据库地址
        :param username: 数据库用户名
        :param password: 数据库密码
        :param database: 数据库名称
        :param kwargs: 可选其他数据库参数（如端口、超时等）
        """
        self.connection_args = {
            'host': host,
            'user': username,
            'password': password,
            'database': database,
            'charset': 'utf8mb4',
            'cursorclass': pymysql.cursors.DictCursor,
        }
        self.connection_args.update(kwargs)
        self.conn = None
        self._connect()
        logging.basicConfig(level=logging.INFO, format="%(asctime)s - %(levelname)s - %(message)s")

    def _connect(self):
        """建立数据库连接，支持断开后自动重连。"""
        try:
            if self.conn is None or not self.conn.open:
                self.conn = pymysql.connect(**self.connection_args)
                logging.info("成功连接到数据库。")
        except pymysql.MySQLError as e:
            logging.error(f"数据库连接失败: {e}")
            raise

    def execute_query(self, sql: str, params: tuple = None) -> list[dict]:
        """
        执行 SELECT 查询。

        :param sql: 查询的 SQL 语句
        :param params: 可选的 SQL 参数
        :return: 查询结果的列表，每条记录为字典
        """
        self._connect()
        try:
            with self.conn.cursor() as cursor:
                cursor.execute(sql, params)
                results = cursor.fetchall()
                logging.info(f"成功执行查询: {sql}")
                return results
        except pymysql.MySQLError as e:
            logging.error(f"查询失败: {e} -> SQL: {sql}")
            raise

    def execute_update(self, sql: str, params: tuple = None) -> int:
        """
        执行 INSERT/UPDATE/DELETE 操作。

        :param sql: 执行的 SQL 语句
        :param params: 可选的 SQL 参数
        :return: 受影响的行数
        """
        self._connect()
        try:
            with self.conn.cursor() as cursor:
                cursor.execute(sql, params)
                self.conn.commit()
                logging.info(f"成功执行更新: {sql}")
                return cursor.rowcount
        except pymysql.MySQLError as e:
            self.conn.rollback()
            logging.error(f"更新失败: {e} -> SQL: {sql}")
            raise

    def execute_many(self, sql: str, param_list: list[tuple]) -> int:
        """
        批量执行 SQL 语句。

        :param sql: 执行的 SQL 语句
        :param param_list: 参数列表，每个元素是参数元组
        :return: 受影响的总行数
        """
        self._connect()
        try:
            with self.conn.cursor() as cursor:
                rowcount = cursor.executemany(sql, param_list)
                self.conn.commit()
                logging.info(f"成功批量执行 SQL，共影响 {rowcount} 行。")
                return rowcount
        except pymysql.MySQLError as e:
            self.conn.rollback()
            logging.error(f"批量操作失败: {e} -> SQL: {sql}")
            raise

    def close(self):
        """关闭数据库连接。"""
        if self.conn and self.conn.open:
            self.conn.close()
            logging.info("数据库连接已关闭。")

    def __del__(self):
        """析构时确保连接关闭。"""
        self.close()