from __future__ import annotations

import os
from collections.abc import Generator

from dotenv import load_dotenv
from sqlalchemy import create_engine
from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker

load_dotenv()

DATABASE_URL = os.getenv("DATABASE_URL", "sqlite:///./notebooklm.db")

is_sqlite = DATABASE_URL.startswith("sqlite")
connect_args = {"check_same_thread": False} if is_sqlite else {}

engine = create_engine(DATABASE_URL, connect_args=connect_args)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)


class Base(DeclarativeBase):
    pass


def get_db() -> Generator[Session, None, None]:
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


def init_db() -> None:
    # Import models here so metadata is fully registered before create_all.
    import data.models  # noqa: F401

    Base.metadata.create_all(bind=engine)