from celery import shared_task
import csv
import io
import logging
from django.utils import timezone
from django.core.files.base import ContentFile
from .models import Contact, ContactGroup, ContactImport

logger = logging.getLogger(__name__)


@shared_task
def process_contact_import(import_id):
    """Process contact import from CSV file."""
    try:
        import_obj = ContactImport.objects.get(id=import_id)
        import_obj.status = 'processing'
        import_obj.save()
        
        # Read CSV file
        csv_file = import_obj.file.read().decode('utf-8')
        csv_reader = csv.DictReader(io.StringIO(csv_file))
        
        total_contacts = 0
        imported_contacts = 0
        failed_contacts = 0
        error_log = []
        
        for row in csv_reader:
            total_contacts += 1
            
            try:
                # Extract contact data
                first_name = row.get('First Name', '').strip()
                last_name = row.get('Last Name', '').strip()
                email = row.get('Email', '').strip()
                
                if not email:
                    error_log.append(f"Row {total_contacts}: Email is required")
                    failed_contacts += 1
                    continue
                
                # Check if contact already exists
                if Contact.objects.filter(user=import_obj.user, email=email).exists():
                    error_log.append(f"Row {total_contacts}: Contact with email {email} already exists")
                    failed_contacts += 1
                    continue
                
                # Get or create group
                group = None
                group_name = row.get('Group', '').strip()
                if group_name:
                    group, created = ContactGroup.objects.get_or_create(
                        user=import_obj.user,
                        name=group_name,
                        defaults={'description': f'Imported from {import_obj.filename}'}
                    )
                
                # Create contact
                contact = Contact.objects.create(
                    user=import_obj.user,
                    group=group,
                    first_name=first_name,
                    last_name=last_name,
                    email=email,
                    phone=row.get('Phone', '').strip(),
                    company=row.get('Company', '').strip(),
                    job_title=row.get('Job Title', '').strip(),
                    address_line1=row.get('Address Line 1', '').strip(),
                    address_line2=row.get('Address Line 2', '').strip(),
                    city=row.get('City', '').strip(),
                    state=row.get('State', '').strip(),
                    postal_code=row.get('Postal Code', '').strip(),
                    country=row.get('Country', '').strip(),
                    website=row.get('Website', '').strip(),
                    linkedin=row.get('LinkedIn', '').strip(),
                    twitter=row.get('Twitter', '').strip(),
                    facebook=row.get('Facebook', '').strip(),
                    notes=row.get('Notes', '').strip(),
                    is_favorite=row.get('Is Favorite', '').lower() == 'true',
                    is_blocked=row.get('Is Blocked', '').lower() == 'true',
                )
                
                imported_contacts += 1
                logger.info(f"Imported contact {contact.id} for user {import_obj.user.id}")
                
            except Exception as e:
                error_log.append(f"Row {total_contacts}: {str(e)}")
                failed_contacts += 1
                logger.error(f"Error importing contact row {total_contacts}: {str(e)}")
        
        # Update import status
        import_obj.status = 'completed'
        import_obj.total_contacts = total_contacts
        import_obj.imported_contacts = imported_contacts
        import_obj.failed_contacts = failed_contacts
        import_obj.error_log = '\n'.join(error_log)
        import_obj.completed_at = timezone.now()
        import_obj.save()
        
        logger.info(f"Contact import {import_id} completed: {imported_contacts} imported, {failed_contacts} failed")
        
    except Exception as e:
        logger.error(f"Failed to process contact import {import_id}: {str(e)}")
        try:
            import_obj = ContactImport.objects.get(id=import_id)
            import_obj.status = 'failed'
            import_obj.error_log = str(e)
            import_obj.save()
        except ContactImport.DoesNotExist:
            pass


@shared_task
def cleanup_contact_imports():
    """Clean up old contact import files."""
    try:
        from django.utils import timezone
        from datetime import timedelta
        
        # Delete import files older than 7 days
        cutoff_date = timezone.now() - timedelta(days=7)
        old_imports = ContactImport.objects.filter(
            created_at__lt=cutoff_date,
            status__in=['completed', 'failed']
        )
        
        count = old_imports.count()
        for import_obj in old_imports:
            if import_obj.file:
                import_obj.file.delete()
            import_obj.delete()
        
        logger.info(f"Cleaned up {count} old contact import files")
        
    except Exception as e:
        logger.error(f"Failed to cleanup contact imports: {str(e)}")