import os
import aiomysql
from common.utils import get_env

_pool: aiomysql.Pool | None = None


async def get_pool() -> aiomysql.Pool:
    global _pool
    if _pool is None:
        _pool = await aiomysql.create_pool(
            host=get_env("MYSQL_HOST"),
            port=int(os.getenv("MYSQL_PORT", "3306")),
            user=get_env("MYSQL_USER"),
            password=get_env("MYSQL_PASSWORD"),
            db=get_env("MYSQL_DB"),
            charset="utf8mb4",
            minsize=0,
            maxsize=30,
            connect_timeout=10,
        )
    return _pool


async def execute(sql: str, args: tuple = ()) -> int:
    pool = await get_pool()
    async with pool.acquire() as conn:
        try:
            async with conn.cursor() as cur:
                await cur.execute(sql, args)
                await conn.commit()
                return cur.lastrowid
        finally:
            conn.close()


async def fetchone(sql: str, args: tuple = ()) -> dict | None:
    pool = await get_pool()
    async with pool.acquire() as conn:
        try:
            async with conn.cursor(aiomysql.DictCursor) as cur:
                await cur.execute(sql, args)
                return await cur.fetchone()
        finally:
            conn.close()


async def fetchall(sql: str, args: tuple = ()) -> list[dict]:
    pool = await get_pool()
    async with pool.acquire() as conn:
        try:
            async with conn.cursor(aiomysql.DictCursor) as cur:
                await cur.execute(sql, args)
                return await cur.fetchall()
        finally:
            conn.close()