from django.core.management.base import BaseCommand
from django.db import transaction, models
from apps.hadis.models import Hadis, HadisCorrection, TransmitterOriginalText

class Command(BaseCommand):
    help = 'Refreshes slugs and share_links by re-saving all existing instances of models that store share_links in the database.'

    def add_arguments(self, parser):
        parser.add_argument(
            '--missing-only',
            action='store_true',
            help='Only update share_links that are empty or null',
        )

    def handle(self, *args, **options):
        missing_only = options.get('missing_only')
        
        models_to_refresh = [
            (Hadis, "Hadis"),
            (HadisCorrection, "Hadis Correction"),
            (TransmitterOriginalText, "Transmitter Original Text"),
        ]

        for model_class, name in models_to_refresh:
            self.stdout.write(self.style.WARNING(f'--- Processing {name} ---'))
            
            if missing_only:
                instances = model_class.objects.filter(
                    models.Q(share_link__isnull=True) | models.Q(share_link='')
                )
            else:
                instances = model_class.objects.all()
                
            count = instances.count()
            
            if count == 0:
                self.stdout.write(f"No {name} instances found to process.")
                continue

            processed = 0
            # Using transaction.atomic to ensure database integrity
            with transaction.atomic():
                for instance in instances:
                    try:
                        # Re-saving triggers the updated .save() logic which regenerates the share_link
                        instance.save()
                        processed += 1
                        
                        if processed % 100 == 0:
                            self.stdout.write(f"Updated {processed}/{count} {name}...")
                            
                    except Exception as e:
                        self.stdout.write(self.style.ERROR(
                            f"Error saving {name} ID {instance.id}: {str(e)}"
                        ))

            self.stdout.write(self.style.SUCCESS(f'Successfully processed {processed} {name} instances.'))

        self.stdout.write(self.style.SUCCESS('--- All models processed successfully ---'))