from django.http import JsonResponse
from django.views.decorators.http import require_http_methods
from django.contrib.auth.decorators import login_required
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import PermissionDenied
from django.shortcuts import get_object_or_404
import json
import logging

from .models import Photo

logger = logging.getLogger(__name__)

@login_required
@require_http_methods(["POST"])
def upload_photo(request):
    """Handle photo upload for any model"""
    try:
        # Get app label, model, and object ID
        app_label = request.POST.get('app_label')
        model = request.POST.get('model')
        object_id = request.POST.get('object_id')
        
        # Log received data
        logger.debug(f"Received upload request - app_label: {app_label}, model: {model}, object_id: {object_id}")
        logger.debug(f"Files in request: {request.FILES}")
        
        # Validate required fields
        missing_fields = []
        if not app_label:
            missing_fields.append('app_label')
        if not model:
            missing_fields.append('model')
        if not object_id:
            missing_fields.append('object_id')
        if 'image' not in request.FILES:
            missing_fields.append('image')
        
        if missing_fields:
            return JsonResponse({
                'error': f'Missing required fields: {", ".join(missing_fields)}'
            }, status=400)
        
        # Get content type
        try:
            content_type = ContentType.objects.get(
                app_label=app_label.lower(),
                model=model.lower()
            )
        except ContentType.DoesNotExist:
            return JsonResponse({
                'error': f'Invalid content type: {app_label}.{model}'
            }, status=400)
        
        # Get the object instance
        try:
            obj = content_type.get_object_for_this_type(id=object_id)
        except Exception as e:
            return JsonResponse({
                'error': f'Object not found: {app_label}.{model} with id {object_id}. Error: {str(e)}'
            }, status=404)
        
        # Check if user has permission to add photos
        if not request.user.has_perm('media.add_photo'):
            logger.warning(f"User {request.user} attempted to upload photo without permission")
            return JsonResponse({
                'error': 'You do not have permission to upload photos'
            }, status=403)
        
        # Create the photo
        photo = Photo.objects.create(
            image=request.FILES['image'],
            content_type=content_type,
            object_id=obj.id,
            uploaded_by=request.user,  # Add the user who uploaded the photo
            # Set as primary if it's the first photo
            is_primary=not Photo.objects.filter(
                content_type=content_type,
                object_id=obj.id
            ).exists()
        )
        
        return JsonResponse({
            'id': photo.id,
            'url': photo.image.url,
            'caption': photo.caption,
            'is_primary': photo.is_primary
        })
    
    except Exception as e:
        logger.error(f"Error in upload_photo: {str(e)}", exc_info=True)
        return JsonResponse({
            'error': f'An error occurred while uploading the photo: {str(e)}'
        }, status=400)

@login_required
@require_http_methods(["POST"])
def set_primary_photo(request, photo_id):
    """Set a photo as primary"""
    try:
        photo = get_object_or_404(Photo, id=photo_id)
        
        # Check if user has permission to edit photos
        if not request.user.has_perm('media.change_photo'):
            return JsonResponse({
                'error': 'You do not have permission to edit photos'
            }, status=403)
        
        # Set this photo as primary
        photo.is_primary = True
        photo.save()  # This will automatically unset other primary photos
        
        return JsonResponse({'status': 'success'})
    
    except Exception as e:
        logger.error(f"Error in set_primary_photo: {str(e)}", exc_info=True)
        return JsonResponse({'error': str(e)}, status=400)

@login_required
@require_http_methods(["POST"])
def update_caption(request, photo_id):
    """Update a photo's caption"""
    try:
        photo = get_object_or_404(Photo, id=photo_id)
        
        # Check if user has permission to edit photos
        if not request.user.has_perm('media.change_photo'):
            return JsonResponse({
                'error': 'You do not have permission to edit photos'
            }, status=403)
        
        # Update caption
        data = json.loads(request.body)
        photo.caption = data.get('caption', '')
        photo.save()
        
        return JsonResponse({
            'id': photo.id,
            'caption': photo.caption
        })
    
    except Exception as e:
        logger.error(f"Error in update_caption: {str(e)}", exc_info=True)
        return JsonResponse({'error': str(e)}, status=400)

@login_required
@require_http_methods(["DELETE"])
def delete_photo(request, photo_id):
    """Delete a photo"""
    try:
        photo = get_object_or_404(Photo, id=photo_id)
        
        # Check if user has permission to delete photos
        if not request.user.has_perm('media.delete_photo'):
            return JsonResponse({
                'error': 'You do not have permission to delete photos'
            }, status=403)
        
        photo.delete()
        return JsonResponse({'status': 'success'})
    
    except Exception as e:
        logger.error(f"Error in delete_photo: {str(e)}", exc_info=True)
        return JsonResponse({'error': str(e)}, status=400)