"""Database engine and session handling."""
from __future__ import annotations

from collections.abc import Iterator

from sqlalchemy import create_engine
from sqlalchemy.orm import Session, sessionmaker

from .config import get_settings

settings = get_settings()

_connect_args = {"check_same_thread": False} if settings.database_url.startswith("sqlite") else {}
engine = create_engine(settings.database_url, pool_pre_ping=True, connect_args=_connect_args)
SessionLocal = sessionmaker(bind=engine, autoflush=False, expire_on_commit=False)


def get_db() -> Iterator[Session]:
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


def init_db() -> None:
    from . import models  # noqa: F401  (registers the tables)

    models.Base.metadata.create_all(engine)