"""Notification service."""
from typing import Optional

from sqlalchemy.orm import Session

from app.models.notification import Notification


def create_notification(
    db: Session,
    user_id: int,
    type: str,
    title: str,
    message: str,
    booking_id: Optional[int] = None,
) -> Notification:
    """
    Create a new notification.

    Args:
        db: Database session
        user_id: ID of the user to notify
        type: Notification type (e.g., 'booking_created', 'booking_approved')
        title: Notification title
        message: Notification message
        booking_id: Optional booking ID this notification relates to

    Returns:
        Created notification object
    """
    notification = Notification(
        user_id=user_id,
        type=type,
        title=title,
        message=message,
        booking_id=booking_id,
    )
    db.add(notification)
    db.commit()
    db.refresh(notification)
    return notification