import json
import os
from django.conf import settings
from django.core.management.base import BaseCommand
from django.db.models import F
from sorl.thumbnail.models import KVStore
from boxes.models import Thing


class Command(BaseCommand):
    help = 'Clean up orphaned images and thumbnails from deleted things'

    def add_arguments(self, parser):
        parser.add_argument(
            '--dry-run',
            action='store_true',
            dest='dry_run',
            help='Show what would be deleted without actually deleting',
        )

    def handle(self, *args, **options):
        dry_run = options.get('dry_run', False)
        
        if dry_run:
            self.stdout.write(self.style.WARNING('DRY RUN - No files will be deleted'))
        
        self.stdout.write('Finding orphaned images and thumbnails...')
        
        media_root = settings.MEDIA_ROOT
        cache_root = os.path.join(media_root, 'cache')
        things_root = os.path.join(media_root, 'things')
        
        if not os.path.exists(things_root):
            self.stdout.write(self.style.WARNING('No things directory found'))
            return
        
        valid_paths = set()
        for thing in Thing.objects.exclude(picture__exact='').exclude(picture__isnull=True):
            if thing.picture:
                valid_paths.add(os.path.basename(thing.picture.name))
        
        self.stdout.write(f'Found {len(valid_paths)} valid images in database')
        
        orphaned_thumbnail_paths = set()
        db_cache_paths = set()
        
        for kvstore in KVStore.objects.filter(key__startswith='sorl-thumbnail||image||'):
            try:
                data = json.loads(kvstore.value)
                name = data.get('name', '')
                if name.startswith('things/'):
                    filename = os.path.basename(name)
                    if filename not in valid_paths:
                        image_hash = kvstore.key.split('||')[-1]
                        thumbnail_kvstore = KVStore.objects.filter(key=f'sorl-thumbnail||thumbnails||{image_hash}').first()
                        if thumbnail_kvstore:
                            thumbnail_list = json.loads(thumbnail_kvstore.value)
                            for thumbnail_hash in thumbnail_list:
                                thumbnail_image_kvstore = KVStore.objects.filter(key=f'sorl-thumbnail||image||{thumbnail_hash}').first()
                                if thumbnail_image_kvstore:
                                    thumbnail_data = json.loads(thumbnail_image_kvstore.value)
                                    thumbnail_path = thumbnail_data.get('name', '')
                                    if thumbnail_path.startswith('cache/'):
                                        orphaned_thumbnail_paths.add(thumbnail_path)
                elif name.startswith('cache/'):
                    db_cache_paths.add(name)
            except (json.JSONDecodeError, KeyError, AttributeError):
                pass
        
        deleted_count = 0
        thumbnail_deleted_count = 0
        empty_dirs_removed = 0
        
        for root, dirs, files in os.walk(things_root, topdown=False):
            for filename in files:
                file_path = os.path.join(root, filename)
                relative_path = os.path.relpath(file_path, things_root)
                
                if relative_path not in valid_paths:
                    deleted_count += 1
                    if dry_run:
                        self.stdout.write(f'Would delete: {file_path}')
                    else:
                        try:
                            os.remove(file_path)
                            self.stdout.write(f'Deleted: {file_path}')
                        except OSError as e:
                            self.stdout.write(self.style.ERROR(f'Failed to delete {file_path}: {e}'))
            
            for dirname in dirs:
                dir_path = os.path.join(root, dirname)
                if not os.listdir(dir_path):
                    if dry_run:
                        self.stdout.write(f'Would remove empty directory: {dir_path}')
                    else:
                        try:
                            os.rmdir(dir_path)
                            self.stdout.write(f'Removed empty directory: {dir_path}')
                            empty_dirs_removed += 1
                        except OSError as e:
                            self.stdout.write(self.style.ERROR(f'Failed to remove {dir_path}: {e}'))
        
        if os.path.exists(cache_root):
            for root, dirs, files in os.walk(cache_root, topdown=False):
                for filename in files:
                    file_path = os.path.join(root, filename)
                    relative_path = os.path.relpath(file_path, media_root)
                    
                    if relative_path in orphaned_thumbnail_paths:
                        thumbnail_deleted_count += 1
                        if dry_run:
                            self.stdout.write(f'Would delete thumbnail (orphaned image): {file_path}')
                        else:
                            try:
                                os.remove(file_path)
                                self.stdout.write(f'Deleted thumbnail (orphaned image): {file_path}')
                            except OSError as e:
                                self.stdout.write(self.style.ERROR(f'Failed to delete {file_path}: {e}'))
                    elif relative_path not in db_cache_paths:
                        thumbnail_deleted_count += 1
                        if dry_run:
                            self.stdout.write(f'Would delete thumbnail (no db entry): {file_path}')
                        else:
                            try:
                                os.remove(file_path)
                                self.stdout.write(f'Deleted thumbnail (no db entry): {file_path}')
                            except OSError as e:
                                self.stdout.write(self.style.ERROR(f'Failed to delete {file_path}: {e}'))
                
                for dirname in dirs:
                    dir_path = os.path.join(root, dirname)
                    if not os.listdir(dir_path):
                        if dry_run:
                            self.stdout.write(f'Would remove empty cache directory: {dir_path}')
                        else:
                            try:
                                os.rmdir(dir_path)
                                empty_dirs_removed += 1
                            except OSError as e:
                                self.stdout.write(self.style.ERROR(f'Failed to remove {dir_path}: {e}'))
        
        if dry_run:
            self.stdout.write(self.style.WARNING(f'\nDry run complete. Would delete {deleted_count} images and {thumbnail_deleted_count} thumbnails'))
            self.stdout.write(f'Would remove {empty_dirs_removed} empty directories')
        else:
            self.stdout.write(self.style.SUCCESS(f'\nCleanup complete! Deleted {deleted_count} images and {thumbnail_deleted_count} thumbnails'))
            self.stdout.write(f'Removed {empty_dirs_removed} empty directories')