from sqlmodel import SQLModel, create_engine, Session
from pydantic_settings import BaseSettings
from typing import Optional, List

class Settings(BaseSettings):
    DATABASE_URL: Optional[str] = None  # Default to None if not set

    class Config:
        env_file = ".env"  # Load from an optional .env file

settings = Settings()
engine = create_engine(settings.DATABASE_URL) if settings.DATABASE_URL else None


def get_db_session():
    if engine is None:
        raise RuntimeError("Database is not configured. Set DATABASE_URL in environment variables.")
    return Session(engine)

def init_db():
    if engine:
        SQLModel.metadata.create_all(engine)