from courses.models import Course, Lesson
from rest_framework.renderers import JSONRenderer
from rest_framework.response import Response
from rest_framework.views import APIView
from django.contrib.auth import get_user_model

from courses.serializers import CourseDetailSerializer, CourseTreeSerializer, LessonSerializer, TeacherLessonSerializer
from progress.models import ProgressLesson


class TreeView(APIView):
    renderer_classes = (JSONRenderer,)
    status_code = 200

    def get(self, request, slug):

        try:
            course = Course.objects.get(slug=slug)
            return Response(CourseTreeSerializer(course).data, self.status_code)
        except Course.DoesNotExist:
            return Response("Course doesn't exist", status=404)


class CourseListView(APIView):
    renderer_classes = (JSONRenderer,)
    status_code = 200

    def post(self, request):
        # TODO: Костыль
        teachers_emails = request.JSON.get('teachers', [])
        request.JSON['teachers'] = [get_user_model().objects.get(email=i).out_key for i in teachers_emails]
        course = Course.objects.update_or_create_course(**request.JSON.dict())
        return Response(CourseDetailSerializer(course).data, status=self.status_code)

    def get(self, request):
        res = [CourseDetailSerializer(course).data for course in Course.objects.all()]
        return Response(res, self.status_code)


class CourseDetailView(APIView):
    renderer_classes = (JSONRenderer,)
    status_code = 200

    @staticmethod
    def delete(request, slug):
        try:
            Course.objects.get(slug=slug).delete()
        except Course.DoesNotExist:
            return Response("Курса не существует", status=404)
        return Response(status=204)

    def get(self, request, slug):
        return Response(CourseDetailSerializer(Course.objects.get(slug=slug)).data, self.status_code)


class LessonInfoView(APIView):
    renderer_classes = (JSONRenderer,)
    status_code = 200

    def get(self, request, token):
        try:
            lesson = Lesson.objects.get(token=token)
        except Lesson.DoesNotExist:
            return Response('Урок не найден', status=404)
        if request.user.is_authenticated and request.user.out_key in lesson.topic.course.teacher_tokens:
            return Response(TeacherLessonSerializer(lesson).data, self.status_code)
        return Response("Пользователь не является преподователем по курсу", status=403)


class LessonDetail(APIView):
    renderer_classes = (JSONRenderer,)

    @staticmethod
    def get(request, token):

        try:
            lesson = Lesson.objects.get(token=token)
        except Lesson.DoesNotExist:
            return Response("Lesson doesn't exist", status=404)

        if not lesson.free and not ProgressLesson.objects.filter(lesson_token=lesson.token).exists():
            previous_lesson = lesson.topic.course.get_previous(lesson)

            if not previous_lesson is None or not ProgressLesson.objects.filter(
                    lesson_token=previous_lesson.token, status=ProgressLesson.STATUSES.done).exists():
                return Response("Lesson doesn't access", status=403)

                # TODO: Доделать систему прав на курс

        res = LessonSerializer(lesson).data
        # progress = vertex.course.progress_set.filter(user=request.user)
        # try:
        #     if progress.exists():
        #         next_vertex = vertex.get_next(progress[0].get_template())
        #         if next_vertex:
        #             res['next'] = MiniVertexSerializer(next_vertex).data
        #         res['is_in_progress'] = vertex in progress[0].get_objects_in_progress()
        #     else:
        #         res['next'] = MiniVertexSerializer(vertex.get_next(vertex.course.route)).data
        # except Thread.DoesNotExist or Vertex.DoesNotExist:
        #     res['next'] = MiniVertexSerializer(vertex.get_next(vertex.course.route)).data

        return Response(res, status=200)