"""Notification emission helpers.

Provides async (for routers) and sync (for Celery tasks) entry points
to create notification rows in the audit_log table.
"""
import logging
import uuid
from datetime import datetime

from sqlalchemy import create_engine
from sqlalchemy.orm import Session
from sqlalchemy.ext.asyncio import AsyncSession

from app.domains.notifications.models import AuditLog

logger = logging.getLogger(__name__)

_engine = None


def _get_engine():
    global _engine
    if _engine is None:
        from app.config import settings as app_settings
        _engine = create_engine(app_settings.database_url_sync)
    return _engine


async def emit_notification(
    db: AsyncSession,
    *,
    actor_user_id: str | uuid.UUID | None = None,
    target_user_id: str | uuid.UUID | None = None,
    action: str,
    entity_type: str | None = None,
    entity_id: str | None = None,
    details: dict | None = None,
) -> None:
    """Create a notification (async — for use inside FastAPI routers)."""
    try:
        entry = AuditLog(
            user_id=str(actor_user_id) if actor_user_id else None,
            target_user_id=str(target_user_id) if target_user_id else None,
            action=action,
            entity_type=entity_type,
            entity_id=str(entity_id) if entity_id else None,
            details=details,
            notification=True,
            timestamp=datetime.utcnow(),
        )
        db.add(entry)
        await db.commit()
    except Exception:
        logger.exception("Failed to emit notification (async)")
        await db.rollback()


def emit_notification_sync(
    *,
    actor_user_id: str | uuid.UUID | None = None,
    target_user_id: str | uuid.UUID | None = None,
    action: str,
    entity_type: str | None = None,
    entity_id: str | None = None,
    details: dict | None = None,
) -> None:
    """Create a notification (sync — for use inside Celery tasks)."""
    engine = _get_engine()
    try:
        with Session(engine) as session:
            entry = AuditLog(
                user_id=str(actor_user_id) if actor_user_id else None,
                target_user_id=str(target_user_id) if target_user_id else None,
                action=action,
                entity_type=entity_type,
                entity_id=str(entity_id) if entity_id else None,
                details=details,
                notification=True,
                timestamp=datetime.utcnow(),
            )
            session.add(entry)
            session.commit()
    except Exception:
        logger.exception("Failed to emit notification (sync)")