feat

apps/course/models/lesson.py

@@ -44,6 +44,45 @@ class Lesson(models.Model):
         return self.completions.filter(student=student).exists()
     
     
+    def save(self, *args, **kwargs):
+        print(f'---> start')
+        if self.priority is None:
+            # If priority is not set, set it to the next available priority
+            max_priority = self.course.lessons.aggregate(max_priority=models.Max('priority'))['max_priority']
+            self.priority = (max_priority or 0) + 1
+        else:
+            self._adjust_priorities()
+        super().save(*args, **kwargs)
+
+
+    def _adjust_priorities(self):
+        # Adjust priorities of other lessons in the course
+        lessons = self.course.lessons.exclude(pk=self.pk)
+        # Shift priorities for lessons with the same or higher priority
+        lessons.filter(priority__gte=self.priority).update(priority=models.F('priority') + 1)
+        
+        
+            # # If priority is set, adjust the priorities of other lessons
+            # lessons = self.course.lessons.exclude(pk=self.pk).order_by('priority')
+            
+            # updated_priorities = []
+            # inserted = False
+
+            # for lesson in lessons:
+            #     if lesson.priority >= self.priority and not inserted:
+            #         updated_priorities.append((self.priority, self))
+            #         inserted = True
+            #     updated_priorities.append((lesson.priority if not inserted else lesson.priority + 1, lesson))
+
+            # if not inserted:
+            #     updated_priorities.append((self.priority, self))
+
+            # # Update priorities in bulk
+            # for priority, lesson in updated_priorities:
+            #     lesson.priority = priority
+            #     lesson.save(update_fields=['priority'])
+
+    
 
 class LessonCompletion(models.Model):
     student = models.ForeignKey(

apps/course/serializers/course.py

@@ -2,7 +2,7 @@ from rest_framework import serializers
 
 from dj_filer.admin import get_thumbs
 
-from apps.course.models import Course, CourseCategory, Attachment, Glossary, LessonCompletion, Participant
+from apps.course.models import Course, CourseCategory, Attachment, Glossary, LessonCompletion, Participant, Lesson
 from apps.account.serializers import UserProfileSerializer
 
 
@@ -67,6 +67,7 @@ class CourseDetailSerializer(serializers.ModelSerializer):
     access = serializers.SerializerMethodField()
     lessons_complated_count = serializers.SerializerMethodField()
     lessons_count = serializers.SerializerMethodField()
+    last_lesson_id = serializers.SerializerMethodField()
     
     class Meta:
         model = Course        
@@ -96,8 +97,39 @@ class CourseDetailSerializer(serializers.ModelSerializer):
             'final_price',
             'timing',
             'features',
+            'last_lesson_id'
         ]
 
+    def get_last_lesson_id(self, obj):
+        request = self.context.get('request')
+        if request and request.user.is_authenticated:
+            user = request.user
+            
+            # آخرین درس تکمیل‌شده توسط کاربر
+            last_completed_lesson = LessonCompletion.objects.filter(
+                student=user,
+                lesson__course=obj
+            ).order_by('-completed_at').first()
+            
+            if last_completed_lesson:
+                # پیدا کردن درس بعدی بر اساس priority
+                next_lesson = Lesson.objects.filter(
+                    course=obj,
+                    priority__gt=last_completed_lesson.lesson.priority,
+                    is_active=True
+                ).order_by('priority').first()
+            else:
+                # اگر هیچ درسی تکمیل نشده باشد، اولین درس را برگردان
+                next_lesson = Lesson.objects.filter(
+                    course=obj,
+                    is_active=True
+                ).order_by('priority').first()
+            if next_lesson:
+                return next_lesson.id
+        return None
+            
+            
+            
     def get_access(self, obj):
         if student := self._get_authenticated_user():
             if not self._is_participant(student, obj):

apps/course/views/lesson.py

@@ -44,40 +44,60 @@ class LessonDetailView(RetrieveAPIView):
     def get(self, request, *args, **kwargs):
         lesson_id = self.kwargs.get('id')
         lesson = get_object_or_404(Lesson, id=lesson_id, is_active=True)
-        
-        # Get the next and previous lessons based on priority and id
-        next_lesson = Lesson.objects.filter(
-            course=lesson.course,
-            is_active=True,
-            priority__gte=lesson.priority,
-            id__gt=lesson.id
-        ).order_by('priority', 'id').first()
-
-        previous_lesson = Lesson.objects.filter(
-            course=lesson.course,
-            is_active=True,
-            priority__lte=lesson.priority,
-            id__lt=lesson.id
-        ).order_by('-priority', '-id').first()
-        total_lessons = Lesson.objects.filter(course=lesson.course, is_active=True).count()
-        # Calculate the current lesson number in the course
-        current_lesson_number = Lesson.objects.filter(
-            course=lesson.course,
-            is_active=True,
-            priority__lte=lesson.priority
-        ).count()
-        
-        # Serialize the current lesson
+
+        course = lesson.course
+        lessons = Lesson.objects.filter(course=course, is_active=True).order_by('priority')
+
+        total_lessons = lessons.count()
+        current_lesson_number = list(lessons.values_list('id', flat=True)).index(lesson.id) + 1
+        next_lesson = lessons.filter(priority__gt=lesson.priority).order_by('priority').first()
+        next_lesson_id = next_lesson.id if next_lesson else None
+        previous_lesson = lessons.filter(priority__lt=lesson.priority).order_by('-priority').first()
+        previous_lesson_id = previous_lesson.id if previous_lesson else None
+
         lesson_data = self.get_serializer(lesson).data
-        # Add current lesson number and total lessons
-        lesson_data['current_lesson_number'] = current_lesson_number
         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
+
+
+
+        
+        # # Get the next and previous lessons based on priority and id
+        # next_lesson = Lesson.objects.filter(
+        #     course=lesson.course,
+        #     is_active=True,
+        #     priority__gte=lesson.priority,
+        #     id__gt=lesson.id
+        # ).order_by('priority', 'id').first()
+
+        # previous_lesson = Lesson.objects.filter(
+        #     course=lesson.course,
+        #     is_active=True,
+        #     priority__lte=lesson.priority,
+        #     id__lt=lesson.id
+        # ).order_by('-priority', '-id').first()
+        
+        # total_lessons = Lesson.objects.filter(course=lesson.course, is_active=True).count()
+        # # Calculate the current lesson number in the course
+        # current_lesson_number = Lesson.objects.filter(
+        #     course=lesson.course,
+        #     is_active=True,
+        #     priority__lte=lesson.priority
+        # ).count()
+        
+        # # Serialize the current lesson
+        # lesson_data = self.get_serializer(lesson).data
+        # # Add current lesson number and total lessons
+        # lesson_data['current_lesson_number'] = current_lesson_number
+        # lesson_data['total_lessons'] = total_lessons
         
-        # Add next and previous lesson ids
-        lesson_data['next_lesson_id'] = next_lesson.id if next_lesson else None
-        lesson_data['previous_lesson_id'] = previous_lesson.id if previous_lesson else None
+        # # Add next and previous lesson ids
+        # lesson_data['next_lesson_id'] = next_lesson.id if next_lesson else None
+        # lesson_data['previous_lesson_id'] = previous_lesson.id if previous_lesson else None
 
-        lesson_data['can_go_next'] = next_lesson is not None
+        # lesson_data['can_go_next'] = next_lesson is not None
 
         return Response(lesson_data)