from __future__ import annotations

from contextlib import contextmanager
from typing import Iterator

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

from app.config import config


class Base(DeclarativeBase):
    pass


engine = create_engine(config.database_url, pool_pre_ping=True, future=True)
SessionLocal = sessionmaker(bind=engine, autoflush=False, expire_on_commit=False, future=True)


def init_db() -> None:
    from app import models  # noqa: F401

    Base.metadata.create_all(bind=engine)


@contextmanager
def session_scope() -> Iterator[Session]:
    session = SessionLocal()
    try:
        yield session
        session.commit()
    except Exception:
        session.rollback()
        raise
    finally:
        session.close()