"""
Complaints Celery tasks

This module contains tasks for:
- Checking overdue complaints
- Sending SLA reminders
- Triggering resolution satisfaction surveys
- Creating PX actions from complaints
"""
import logging

from celery import shared_task
from django.db import transaction
from django.utils import timezone

logger = logging.getLogger(__name__)


@shared_task
def check_overdue_complaints():
    """
    Periodic task to check for overdue complaints.
    
    Runs every 15 minutes (configured in config/celery.py).
    Updates is_overdue flag for complaints past their SLA deadline.
    """
    from apps.complaints.models import Complaint, ComplaintStatus
    
    # Get active complaints (not closed or cancelled)
    active_complaints = Complaint.objects.filter(
        status__in=[ComplaintStatus.OPEN, ComplaintStatus.IN_PROGRESS, ComplaintStatus.RESOLVED]
    ).select_related('hospital', 'patient')
    
    overdue_count = 0
    
    for complaint in active_complaints:
        if complaint.check_overdue():
            overdue_count += 1
            logger.warning(
                f"Complaint {complaint.id} is overdue: {complaint.title} "
                f"(due: {complaint.due_at})"
            )
            
            # TODO: Trigger escalation (Phase 6)
            # from apps.px_action_center.tasks import escalate_complaint
            # escalate_complaint.delay(str(complaint.id))
    
    if overdue_count > 0:
        logger.info(f"Found {overdue_count} overdue complaints")
    
    return {'overdue_count': overdue_count}


@shared_task
def send_complaint_resolution_survey(complaint_id):
    """
    Send resolution satisfaction survey when complaint is closed.
    
    This task is triggered when a complaint status changes to CLOSED.
    
    Args:
        complaint_id: UUID of the Complaint
    
    Returns:
        dict: Result with survey_instance_id
    """
    from apps.complaints.models import Complaint
    from apps.core.services import create_audit_log
    from apps.surveys.models import SurveyInstance, SurveyTemplate
    
    try:
        complaint = Complaint.objects.select_related(
            'patient', 'hospital'
        ).get(id=complaint_id)
        
        # Check if survey already sent
        if complaint.resolution_survey:
            logger.info(f"Resolution survey already sent for complaint {complaint_id}")
            return {'status': 'skipped', 'reason': 'already_sent'}
        
        # Get resolution satisfaction survey template
        try:
            survey_template = SurveyTemplate.objects.get(
                hospital=complaint.hospital,
                survey_type='complaint_resolution',
                is_active=True
            )
        except SurveyTemplate.DoesNotExist:
            logger.warning(
                f"No resolution satisfaction survey template found for hospital {complaint.hospital.name}"
            )
            return {'status': 'skipped', 'reason': 'no_template'}
        
        # Create survey instance
        with transaction.atomic():
            survey_instance = SurveyInstance.objects.create(
                survey_template=survey_template,
                patient=complaint.patient,
                encounter_id=complaint.encounter_id,
                delivery_channel='sms',  # Default
                recipient_phone=complaint.patient.phone,
                recipient_email=complaint.patient.email,
                metadata={
                    'complaint_id': str(complaint.id),
                    'complaint_title': complaint.title
                }
            )
            
            # Link survey to complaint
            complaint.resolution_survey = survey_instance
            complaint.resolution_survey_sent_at = timezone.now()
            complaint.save(update_fields=['resolution_survey', 'resolution_survey_sent_at'])
        
        # Send survey
        from apps.notifications.services import NotificationService
        notification_log = NotificationService.send_survey_invitation(
            survey_instance=survey_instance,
            language='en'  # TODO: Get from patient preference
        )
        
        # Update survey status
        survey_instance.status = 'active'
        survey_instance.sent_at = timezone.now()
        survey_instance.save(update_fields=['status', 'sent_at'])
        
        # Log audit event
        create_audit_log(
            event_type='survey_sent',
            description=f"Resolution satisfaction survey sent for complaint: {complaint.title}",
            content_object=survey_instance,
            metadata={
                'complaint_id': str(complaint.id),
                'survey_template': survey_template.name
            }
        )
        
        logger.info(
            f"Resolution satisfaction survey sent for complaint {complaint.id}"
        )
        
        return {
            'status': 'sent',
            'survey_instance_id': str(survey_instance.id),
            'notification_log_id': str(notification_log.id)
        }
    
    except Complaint.DoesNotExist:
        error_msg = f"Complaint {complaint_id} not found"
        logger.error(error_msg)
        return {'status': 'error', 'reason': error_msg}
    
    except Exception as e:
        error_msg = f"Error sending resolution survey: {str(e)}"
        logger.error(error_msg, exc_info=True)
        return {'status': 'error', 'reason': error_msg}


@shared_task
def create_action_from_complaint(complaint_id):
    """
    Create PX Action from complaint (if configured).
    
    This task is triggered when a complaint is created,
    if the hospital configuration requires automatic action creation.
    
    Args:
        complaint_id: UUID of the Complaint
    
    Returns:
        dict: Result with action_id
    """
    # TODO: Implement in Phase 6
    logger.info(f"Should create PX Action from complaint {complaint_id}")
    return {'status': 'pending_phase_6'}