"""
Django signals for incident intelligence
"""
from django.db.models.signals import post_save, pre_save
from django.dispatch import receiver
from django.utils import timezone
import logging

from .models import Incident

logger = logging.getLogger(__name__)


@receiver(post_save, sender=Incident)
def incident_post_save(sender, instance, created, **kwargs):
    """
    Handle incident post-save events
    """
    if created:
        logger.info(f"New incident created: {instance.id}")
        
        # Trigger AI processing for new incidents
        try:
            from .tasks import process_incident_ai
            process_incident_ai.delay(instance.id)
        except Exception as e:
            logger.error(f"Failed to trigger AI processing for incident {instance.id}: {e}")
    
    # Update resolution time if status changed to resolved
    if not created and instance.status in ['RESOLVED', 'CLOSED'] and not instance.resolved_at:
        instance.resolved_at = timezone.now()
        instance.save(update_fields=['resolved_at'])


@receiver(pre_save, sender=Incident)
def incident_pre_save(sender, instance, **kwargs):
    """
    Handle incident pre-save events
    """
    # Auto-assign priority based on severity
    if instance.severity and not instance.priority:
        severity_priority_map = {
            'EMERGENCY': 'P1',
            'CRITICAL': 'P1',
            'HIGH': 'P2',
            'MEDIUM': 'P3',
            'LOW': 'P4'
        }
        instance.priority = severity_priority_map.get(instance.severity, 'P3')
    
    # Update AI processing flag if key fields changed
    if instance.pk:
        try:
            old_instance = Incident.objects.get(pk=instance.pk)
            ai_relevant_fields = ['title', 'description', 'free_text', 'category', 'subcategory', 'severity']
            
            if any(getattr(old_instance, field) != getattr(instance, field) for field in ai_relevant_fields):
                instance.ai_processed = False
                instance.ai_processing_error = None
        except Incident.DoesNotExist:
            pass