"""
AsyncMySQLClient (基于 asyncmy) + 项目统一日志正式上线版

- 自动管理连接池，避免重复初始化和内存泄漏
- 支持 async with 上下文管理
- 高并发协程安全
"""
import traceback
from typing import List, Dict, Any, Optional, Tuple
import asyncio
import asyncmy

from core.utils.log.logger_manager import LoggerManager

class AsyncMySQLClient:
    # 类变量：同配置单例管理连接池实例
    _instances: Dict[Tuple, "AsyncMySQLClient"] = {}

    def __new__(cls,
                host: str,
                port: int,
                user: str,
                password: str,
                db: str,
                charset: str,
                minsize: int = 1,
                maxsize: int = 5,
                **kwargs):
        """
        单例模式：同配置共享同一连接池实例
        """
        key = (host, port, user, db)
        if key not in cls._instances:
            instance = super().__new__(cls)
            cls._instances[key] = instance
        return cls._instances[key]

    def __init__(self,
                 host: str,
                 port: int,
                 user: str,
                 password: str,
                 db: str,
                 charset: str,
                 minsize: int = 1,
                 maxsize: int = 5,
                 logger: Optional[LoggerManager] = None,
                 aliyun_logr:Optional[LoggerManager] = None,):
        """
        初始化配置，延迟创建连接池
        """
        self._db_settings = {
            "host": host,
            "port": port,
            "user": user,
            "password": password,
            "db": db,
            "autocommit": True,
            "charset": charset,
            "connect_timeout": 5,
        }
        self._minsize = minsize
        self._maxsize = maxsize
        self._pool: Optional[asyncmy.Pool] = None
        self._lock = asyncio.Lock()  # 防止并发初始化

        self.logger = logger
        self.aliyun_logger = aliyun_logr

    async def __aenter__(self):
        """支持 async with 自动初始化连接池"""
        await self.init_pool()
        return self

    async def __aexit__(self, exc_type, exc_val, exc_tb):
        """支持 async with 自动关闭连接池"""
        await self.close()

    async def init_pool(self):
        """
        初始化连接池（懒加载 + 并发锁保护）
        """
        if self._pool:
            return
        async with self._lock:
            if self._pool:
                return
            try:
                self._pool = await asyncmy.create_pool(
                    **self._db_settings,
                    minsize=self._minsize,
                    maxsize=self._maxsize,
                )
            except Exception as e:
                msg = f"[AsyncMySQLClient] 连接池初始化失败: {e} \n {traceback.format_exc()}"
                self.logger.error(msg)
                self.aliyun_logger.logging(code="9001", message=msg, data={f"error: f{traceback.format_exc()} \n {e}"})
                raise

    async def close(self):
        """
        关闭连接池
        """
        if self._pool:
            self._pool.close()
            await self._pool.wait_closed()
            self._pool = None

    async def fetch_all(self, sql: str, params: Optional[List[Any]] = None) -> List[Dict[str, Any]]:
        """
        查询多行，返回字典列表
        """
        await self.init_pool()
        try:
            async with self._pool.acquire() as conn:
                async with conn.cursor() as cur:
                    await cur.execute(sql, params or [])
                    rows = await cur.fetchall()
                    columns = [desc[0] for desc in cur.description]
                    result = [dict(zip(columns, row)) for row in rows]
                    return result
        except Exception as e:
            msg = f"[AsyncMySQLClient] fetch_all 执行失败: {e} | SQL: {sql}"
            self.logger.error(msg)
            self.aliyun_logger.logging(code="9002", message=msg)
            raise

    async def fetch_one(self, sql: str, params: Optional[List[Any]] = None) -> Optional[Dict[str, Any]]:
        """
        查询单行，返回字典
        """
        await self.init_pool()
        try:
            async with self._pool.acquire() as conn:
                async with conn.cursor() as cur:
                    await cur.execute(sql, params or [])
                    row = await cur.fetchone()
                    if row is None:
                        return None
                    columns = [desc[0] for desc in cur.description]
                    result = dict(zip(columns, row))
                    return result
        except Exception as e:
            msg = f"[AsyncMySQLClient] fetch_one 执行失败: {e} | SQL: {sql}"
            self.logger.error(msg)
            self.aliyun_logger.logging(code="9003", message=msg)
            raise

    async def execute(self, sql: str, params: Optional[List[Any]] = None) -> int:
        """
        执行单条写操作
        """
        await self.init_pool()
        try:
            async with self._pool.acquire() as conn:
                async with conn.cursor() as cur:
                    await cur.execute(sql, params or [])
                    return cur.rowcount
        except Exception as e:
            msg = f"[AsyncMySQLClient] execute 执行失败: {e} | SQL: {sql}"
            self.logger.error(msg)
            self.aliyun_logger.logging(code="9004", message=msg)
            raise

    async def executemany(self, sql: str, params_list: List[List[Any]]) -> int:
        """
        批量执行写操作
        """
        await self.init_pool()
        try:
            async with self._pool.acquire() as conn:
                async with conn.cursor() as cur:
                    await cur.executemany(sql, params_list)
                    return cur.rowcount
        except Exception as e:
            msg = f"[AsyncMySQLClient] executemany 执行失败: {e} | SQL: {sql}"
            self.logger.error(msg)
            self.aliyun_logger.logging(code="9005", message=msg)
            raise