from django.shortcuts import render, get_object_or_404
from django.db.models import Q
from quiz.models import QuizSession, Question, QuizResult


def get_next_question(request, session_id):
    session = get_object_or_404(QuizSession, id=session_id, user=request.quiz_user)

    answered_ids = QuizResult.objects.filter(
        user=request.quiz_user,
        quiz_session=session
    ).values_list('question_id', flat=True)

    questions = Question.objects.exclude(id__in=answered_ids)

    # Apply filters from session
    if session.course:
        questions = questions.filter(exam__course=session.course)

    if session.tags.exists():
        questions = questions.filter(tags__in=session.tags.all())

    if session.exams.exists():
        questions = questions.filter(exam__in=session.exams.all())

    if session.question_types:
        q_objs = Q()
        if 'single' in session.question_types:
            q_objs |= ~Q(correct_answer__contains=',')
        if 'multi' in session.question_types:
            q_objs |= Q(correct_answer__contains=',')

        if q_objs:
            questions = questions.filter(q_objs)

    questions = questions.distinct()
    next_question = questions.first()

    if not next_question:
        return render(request, 'partials/complete.html', {'session': session})

    return render(request, 'partials/question.html', {
        'question': next_question,
        'session': session
    })