from rest_framework.generics import ListAPIView, RetrieveAPIView, GenericAPIView from rest_framework.permissions import IsAuthenticated, AllowAny from rest_framework.authentication import TokenAuthentication from drf_yasg.utils import swagger_auto_schema from drf_yasg import openapi from django.shortcuts import get_object_or_404 from rest_framework import status from rest_framework.response import Response from apps.course.models import CourseChapter from apps.course.serializers import ( CourseLessonSerializer, CourseChapterSerializer ) from apps.course.models import Course, CourseLesson, LessonCompletion from apps.course.doc import * from utils.exceptions import AppAPIException from utils.pagination import StandardResultsSetPagination from rest_framework.permissions import IsAuthenticated class LessonListView(ListAPIView): serializer_class = CourseLessonSerializer pagination_class = StandardResultsSetPagination permission_classes = [AllowAny] authentication_classes = [TokenAuthentication] @swagger_auto_schema( operation_description=doc_courses_lesson(), tags=['Imam-Javad - Course'], ) def get(self, request, *args, **kwargs): return super().get(request, *args, **kwargs) def get_queryset(self): """ Optimized queryset with select_related and prefetch_related for lesson relationships """ course_slug = self.kwargs.get('slug') course = get_object_or_404(Course, slug=course_slug) return CourseLesson.objects.select_related( 'chapter', # 👇 Route through chapter 'lesson' ).prefetch_related( 'completions', 'quizzes' ).filter( chapter__course=course, # 👇 Query via chapter is_active=True, chapter__is_active=True ).order_by('chapter__priority', 'priority') # 👇 Sort by chapter first class LessonDetailView(RetrieveAPIView): serializer_class = CourseLessonSerializer permission_classes = [AllowAny] authentication_classes = [TokenAuthentication] @swagger_auto_schema( operation_description="Get detailed lesson information with navigation data", tags=["Imam-Javad - Course"], manual_parameters=[ openapi.Parameter( 'id', openapi.IN_PATH, description="Lesson ID", type=openapi.TYPE_INTEGER, required=True ) ], responses={ 200: openapi.Response( description="Lesson details with navigation information", schema=CourseLessonSerializer() ) } ) def get(self, request, *args, **kwargs): lesson_id = self.kwargs.get('id') course_lesson = get_object_or_404( CourseLesson.objects.select_related('chapter__course', 'lesson'), id=lesson_id, is_active=True, chapter__is_active=True ) course = course_lesson.chapter.course # Get all lessons in order lessons = CourseLesson.objects.select_related( 'lesson', 'chapter' ).filter( chapter__course=course, is_active=True, chapter__is_active=True ).order_by('chapter__priority', 'priority') total_lessons = lessons.count() # Convert to list to find index lesson_ids = list(lessons.values_list('id', flat=True)) try: current_index = lesson_ids.index(course_lesson.id) current_lesson_number = current_index + 1 next_lesson_id = lesson_ids[current_index + 1] if current_index + 1 < len(lesson_ids) else None previous_lesson_id = lesson_ids[current_index - 1] if current_index > 0 else None except ValueError: current_lesson_number = 1 next_lesson_id = None previous_lesson_id = None lesson_data = self.get_serializer(course_lesson).data lesson_data['total_lessons'] = total_lessons lesson_data['current_lesson_number'] = current_lesson_number lesson_data['next_lesson_id'] = next_lesson_id lesson_data['previous_lesson_id'] = previous_lesson_id lesson_data['can_go_next'] = next_lesson_id is not None return Response(lesson_data) class LessonCompletionToggleAPIView(GenericAPIView): permission_classes = [IsAuthenticated] authentication_classes = [TokenAuthentication] @swagger_auto_schema( operation_description="Toggle lesson completion status (Check/Uncheck)", tags=["Imam-Javad - Course"], request_body=openapi.Schema( type=openapi.TYPE_OBJECT, required=['lesson_id'], properties={ 'lesson_id': openapi.Schema(type=openapi.TYPE_INTEGER, description='ID of the lesson to toggle'), }, ), responses={ 201: 'Lesson marked as COMPLETED.', 200: 'Lesson marked as INCOMPLETE (Unchecked).', 400: 'Lesson ID is required.', 404: 'Lesson not found.', } ) def post(self, request): student = request.user lesson_id = request.data.get('lesson_id') if not lesson_id: return Response({'error': 'Lesson ID is required.'}, status=status.HTTP_400_BAD_REQUEST) try: course_lesson = CourseLesson.objects.get(id=lesson_id) except CourseLesson.DoesNotExist: return Response({'error': 'Lesson not found.'}, status=status.HTTP_404_NOT_FOUND) # TOGGLE LOGIC # Try to find an existing completion record completion = LessonCompletion.objects.filter(student=student, course_lesson=course_lesson).first() if completion: # Scenario: The user clicked by mistake or wants to un-check # Action: Delete the record completion.delete() return Response( {'message': 'Lesson marked as incomplete.', 'is_completed': False}, status=status.HTTP_200_OK ) else: # Scenario: The lesson is not finished yet # Action: Create the record LessonCompletion.objects.create(student=student, course_lesson=course_lesson) return Response( {'message': 'Lesson completed successfully.', 'is_completed': True}, status=status.HTTP_201_CREATED ) from django.db.models import Prefetch class LessonListV2APIView(ListAPIView): """ V2 API: Returns lessons grouped by Chapters """ serializer_class = CourseChapterSerializer pagination_class = StandardResultsSetPagination permission_classes = [AllowAny] authentication_classes = [TokenAuthentication] @swagger_auto_schema( operation_description="V2: Get a nested list of chapters and their lessons", tags=['Imam-Javad - Course (V2)'], ) def get(self, request, *args, **kwargs): return super().get(request, *args, **kwargs) def get_queryset(self): course_slug = self.kwargs.get('slug') course = get_object_or_404(Course, slug=course_slug) # We query the Chapters, and prefetch the lessons to avoid N+1 query problems return CourseChapter.objects.prefetch_related( Prefetch( 'lessons', queryset=CourseLesson.objects.select_related('lesson').filter(is_active=True).order_by('priority') ) ).filter( course=course, is_active=True ).order_by('priority', 'id')