"""
Helper functions for user management
"""
from sqlalchemy.ext.asyncio import AsyncSession
from shared.database.models import User
from datetime import datetime
from sqlalchemy.exc import IntegrityError
import logging

logger = logging.getLogger(__name__)


async def ensure_user_exists(user_id: int, db: AsyncSession) -> User:
    """
    Ensure user exists in database, create if not exists.
    
    Args:
        user_id: User ID
        db: Database session
        
    Returns:
        User object (existing or newly created)
    """
    # Check if user exists
    user = await db.get(User, user_id)
    if user:
        return user
    
    # User doesn't exist, create it
    user = User(
        user_id=user_id,
        username=None,
        first_name=None,
        last_name=None,
        is_admin=False,
        is_blocked=False,
        created_at=datetime.utcnow()
    )
    
    try:
        db.add(user)
        await db.commit()
        logger.info(f"Automatically created user {user_id} in database")
        return user
    except IntegrityError:
        # User was created by another request/thread, fetch it
        await db.rollback()
        user = await db.get(User, user_id)
        if user:
            logger.debug(f"User {user_id} was created concurrently, using existing record")
            return user
        else:
            logger.error(f"Failed to create or fetch user {user_id}")
            raise Exception(f"Failed to ensure user {user_id} exists")
    except Exception as e:
        await db.rollback()
        logger.error(f"Error ensuring user {user_id} exists: {e}", exc_info=True)
        raise