import asyncio
from typing import Optional

from sqlalchemy import text
from sqlalchemy.ext.asyncio import create_async_engine, AsyncEngine, async_sessionmaker

from app.conf.app_config import DBConfig, app_config


class MysqlClientManager:
    def __init__(self, db_config: DBConfig):
        self.db_config = db_config
        self.engine: Optional[AsyncEngine] = None
        self.session_factory = None

    def _get_url(self):
        return f"mysql+asyncmy://{self.db_config.user}:{self.db_config.password}@{self.db_config.host}:{self.db_config.port}/{self.db_config.database}?charset=utf8mb4"

    def init(self):
        self.engine = create_async_engine(url=self._get_url(),
                                          pool_size=10,
                                          pool_pre_ping=True)
        self.session_factory = async_sessionmaker(db_assistant_mysql_client_manager.engine,
                                                  autoflush=True,
                                                  expire_on_commit=False)

    async def close(self):
        await self.engine.dispose()


db_assistant_mysql_client_manager = MysqlClientManager(app_config.db_assistant)

if __name__ == '__main__':
    db_assistant_mysql_client_manager.init()


    async def test():
        async with db_assistant_mysql_client_manager.session_factory() as session:
            result = await session.execute(text("select * from archive_messages limit 10"))
            rows = result.mappings().fetchall()
            print(type(rows[0]))
            print(rows)


    asyncio.run(test())