from rest_framework import generics
from rest_framework.exceptions import NotFound
from drf_yasg.utils import swagger_auto_schema
from drf_yasg import openapi
from rest_framework.permissions import IsAuthenticated

from apps.account.models import StudentUser
from apps.course.models import Participant, Course
from apps.course.serializers import ParticipantSerializer
from apps.account.serializers import UserProfileSerializer 
from apps.course.doc import *
from utils.exceptions import AppAPIException
from utils.pagination import StandardResultsSetPagination



class CourseParticipantsView(generics.ListAPIView):
    serializer_class = UserProfileSerializer
    pagination_class = StandardResultsSetPagination

    @swagger_auto_schema(
        operation_description=doc_course_participants(),
        tags=['Imam-Javad - Course'],
    )
    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)
    def get_queryset(self):
        """
        Optimized queryset with select_related for course relationship.
        Filters out guest users (no email) and soft-deleted users (is_active=False).
        """
        course_slug = self.kwargs.get('slug')
        try:
            course = Course.objects.get(slug=course_slug)
        except Course.DoesNotExist:
            raise AppAPIException({'message': "Course not found"})

        # 👇 Apply the strict filters for Normal Users only
        return StudentUser.objects.select_related().filter(
            participated_courses__course=course,
            is_active=True,          # Exclude soft-deleted users
            email__isnull=False      # Exclude guest users
        ).exclude(
            email__exact=''          # Extra safety just in case an email is a blank string
        )




# class ParticipantCreateView(generics.CreateAPIView):
#     queryset = StudentUser.objects.all()
#     serializer_class = ParticipantSerializer
#     permission_classes = [IsAuthenticated] 
    
    
#     def create(self, request, *args, **kwargs):        
#         user = request.user
#         course_slug = self.kwargs.get('slug')  # Get the slug from the URL
#         try:
#             course = Course.objects.get(slug=slug)  # Retrieve the Course object
#         except Course.DoesNotExist:
#             raise AppAPIException({'message': "Course not found"})  # Handle course not found
        
#         if request.data.get('email') != request.user:
#             raise AppAPIException({'message': "The email must be for the requesting user"})

#         if user.user_type != User.UserType.STUDENT: 
#             user.change_user_type(User.UserType.STUDENT)

#         participant, created = Participant.objects.get_or_create(
#             student=user,
#             course=course
#         )
        
#         serializer = self.get_serializer(participant)
#         return Response(serializer.data, status=status.HTTP_201_CREATED)