"""SQLAlchemy engine and session factory setup."""

from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from models import Base

DB_PATH = "sqlite:///wordsearch.db"


def get_engine(db_url=None):
    """Create a SQLAlchemy engine.

    Args:
        db_url: Database URL. Defaults to ``sqlite:///wordsearch.db``.
    """
    return create_engine(db_url or DB_PATH)


def get_session_factory(engine):
    """Return a sessionmaker bound to the given engine."""
    return sessionmaker(bind=engine)


def init_db(engine):
    """Create all tables defined in the ORM models."""
    Base.metadata.create_all(engine)