from typing import AsyncGenerator

from fastapi import Depends
from fastapi_users.db import SQLAlchemyBaseUserTableUUID, SQLAlchemyUserDatabase
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
from sqlalchemy.ext.declarative import DeclarativeMeta, declarative_base
from sqlalchemy.orm import sessionmaker
from dotenv import load_dotenv
import os

# Get the current environment from the environment variable
current_environment = os.getenv("APP_ENV", "dev")

# Load the appropriate .env file based on the current environment
if current_environment == "dev":
    load_dotenv(".env.dev")
elif current_environment == "test":
    load_dotenv(".env.test")
elif current_environment == "prod":
    load_dotenv(".env.prod")
else:
    raise ValueError("Invalid environment specified")

db_connection_string = os.getenv("DB_CONNECTION_STRING")

DATABASE_URL = db_connection_string
Base: DeclarativeMeta = declarative_base()

    
class User(SQLAlchemyBaseUserTableUUID, Base):
    pass


engine = create_async_engine(DATABASE_URL)
async_session_maker = sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


async def create_db_and_tables():
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)


async def get_async_session() -> AsyncGenerator[AsyncSession, None]:
    async with async_session_maker() as session:
        yield session


async def get_user_db(session: AsyncSession = Depends(get_async_session)):
    yield SQLAlchemyUserDatabase(session, User)