import json
from django.views.decorators.csrf import csrf_exempt
from django.http import JsonResponse
from django.utils.decorators import method_decorator
from django.views import View
from mobile_api.utils import validate_token_and_get_user
from eventify_logger.services import log
from .models import Notification


@method_decorator(csrf_exempt, name='dispatch')
class NotificationListView(View):
    def post(self, request):
        try:
            user, token, data, error_response = validate_token_and_get_user(request, error_status_code=True)
            if error_response:
                return error_response

            page = int(data.get('page', 1))
            page_size = int(data.get('page_size', 20))
            offset = (page - 1) * page_size

            notifications = Notification.objects.filter(user=user)[offset:offset + page_size]
            total = Notification.objects.filter(user=user).count()

            items = [{
                'id': n.id,
                'title': n.title,
                'message': n.message,
                'notification_type': n.notification_type,
                'is_read': n.is_read,
                'action_url': n.action_url or '',
                'created_at': n.created_at.isoformat(),
            } for n in notifications]

            return JsonResponse({
                'status': 'success',
                'notifications': items,
                'total': total,
                'page': page,
                'page_size': page_size,
            })
        except Exception as e:
            log("error", "NotificationListView error", request=request, logger_data={"error": str(e)})
            return JsonResponse({'error': 'An unexpected server error occurred.'}, status=500)


@method_decorator(csrf_exempt, name='dispatch')
class NotificationMarkReadView(View):
    def post(self, request):
        try:
            user, token, data, error_response = validate_token_and_get_user(request, error_status_code=True)
            if error_response:
                return error_response

            mark_all = data.get('mark_all', False)
            notification_id = data.get('notification_id')

            if mark_all:
                Notification.objects.filter(user=user, is_read=False).update(is_read=True)
                return JsonResponse({'status': 'success', 'message': 'All notifications marked as read'})

            if notification_id:
                Notification.objects.filter(id=notification_id, user=user).update(is_read=True)
                return JsonResponse({'status': 'success', 'message': 'Notification marked as read'})

            return JsonResponse({'error': 'Provide notification_id or mark_all=true'}, status=400)
        except Exception as e:
            log("error", "NotificationMarkReadView error", request=request, logger_data={"error": str(e)})
            return JsonResponse({'error': 'An unexpected server error occurred.'}, status=500)


@method_decorator(csrf_exempt, name='dispatch')
class NotificationCountView(View):
    def post(self, request):
        try:
            user, token, data, error_response = validate_token_and_get_user(request, error_status_code=True)
            if error_response:
                return error_response

            count = Notification.objects.filter(user=user, is_read=False).count()
            return JsonResponse({'status': 'success', 'unread_count': count})
        except Exception as e:
            log("error", "NotificationCountView error", request=request, logger_data={"error": str(e)})
            return JsonResponse({'error': 'An unexpected server error occurred.'}, status=500)