from collections.abc import Generator

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

from .config import get_settings

settings = get_settings()

# SQLite (used in tests) needs a special connect arg; Postgres does not.
connect_args = {}
if settings.database_url.startswith("sqlite"):
    connect_args = {"check_same_thread": False}

engine = create_engine(
    settings.database_url,
    connect_args=connect_args,
    pool_pre_ping=True,
    future=True,
)

SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False, future=True)


class Base(DeclarativeBase):
    pass


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