import mysql.connector
from mysql.connector import Error

from .config import MYSQL_CONFIG


class Database:
    """MySQL 连接池管理类"""
    pool_config = {
        "host": MYSQL_CONFIG.get("host", "localhost"),
        "port": int(MYSQL_CONFIG.get("port", 3306)),
        "user": MYSQL_CONFIG.get("user", "root"),
        "password": MYSQL_CONFIG.get("password", ""),
        "database": MYSQL_CONFIG.get("database", ""),
        "charset": MYSQL_CONFIG.get("charset", "utf8mb4"),
        "pool_name": "fastapi_pool",
        "pool_size": 5,
        "pool_reset_session": True
    }

    @classmethod
    def get_connection(cls):
        """获取数据库连接"""
        try:
            # 从连接池获取连接
            conn = mysql.connector.connect(**cls.pool_config)
            if conn.is_connected():
                return conn
        except Error as e:
            # 抛出数据库连接错误（会被全局异常处理器捕获）
            raise Exception(f"MySQL 连接失败: {str(e)}") from e

    @classmethod
    def close_connection(cls, conn, cursor=None):
        """关闭连接和游标"""
        try:
            if cursor:
                cursor.close()
            if conn and conn.is_connected():
                conn.close()
        except Error as e:
            raise Exception(f"MySQL 连接关闭失败: {str(e)}") from e


# 暴露数据库操作工具
db = Database()