from django.contrib.auth import get_user_model
from django.contrib import auth
from django.shortcuts import redirect
from rest_framework.permissions import IsAuthenticated
from rest_framework.views import APIView
from rest_framework.renderers import JSONRenderer
from rest_framework.response import Response
from django.db.models import Q

from access.models import Invite, Progress, ExtraPrivilege
from access.serializers import UserInitSerializer, UserSearchSerializer, UserProfileSerializer
from courses.models import Vertex
from journals.models import Thread


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

    def get(self, request):
        return Response([i.email for i in get_user_model().objects.filter(groups__name='teachers')], self.status_code)


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

    def get(self, request):
        if request.user.is_authenticated() and (request.user.is_staff or request.user.is_superuser):
            return Response(True, status=self.status_code)
        return Response(False, status=self.status_code)


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

    def get(self, request):
        if request.user.is_authenticated():
            return Response(UserInitSerializer(request.user).data, status=self.status_code)
        return Response('anonymous', status=self.status_code)


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

    def get(self, request):
        if request.user.is_authenticated() and \
                (request.user.is_superuser
                 or 'managers' in request.user.groups.all() or 'lead_managers' in request.user.groups.all()):

            key = request.GET.get('key', None)
            count = int(request.GET.get('count', '10'))

            if key:
                res = get_user_model().objects.filter(
                    Q(id__contains=key) | Q(email__contains=key.lower()) | Q(first_name__contains=key) |
                    Q(last_name__contains=key) | Q(account__phone__contains=key), groups__name='students'
                )

            else:
                res = get_user_model().objects.all()

            res = res[:(count if len(res) > count else len(res))]

            return Response(
                [UserSearchSerializer(i).data for i in res],
                status=self.status_code
            )

        return Response('Permission denied', status=403)


class DetailUserView(APIView):
    renderer_classes = (JSONRenderer,)
    permission_classes = (IsAuthenticated,)

    @staticmethod
    def get(request, pk):
        if request.user.is_superuser or request.user.is_staff or request.user.id == pk:

            try:
                user = get_user_model().objects.get(id=pk)
            except get_user_model().DoesNotExist:
                return Response("User doesn't exist", status=404)

            serialized_user = UserProfileSerializer(user).data

            serialized_user['is_i'] = request.user == user

            return Response(serialized_user, status=200)

        return Response('Permission denied', status=403)


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

    @staticmethod
    def get(request):
        try:
            invite = Invite.objects.get(hash=request.GET['hash'])
            invite.owner.is_active = True
            invite.owner.save()
            auth.login(request, invite.owner)
            invite.delete()
            return redirect('/')
        except Invite.DoesNotExist:
            return Response('Приглошения не существует возможно оно сгорело', status=404)

    @staticmethod
    def post(request):
        try:
            get_user_model().objects.get(email=request.JSON['email'].lower())
            return Response('user already exist', status=403)
        except get_user_model().DoesNotExist:
            password = request.JSON.get('password')
            if password:
                user = get_user_model().objects.create_student(
                    email=request.JSON['email'].lower(),
                    password=request.JSON['password']
                )
            else:
                user = get_user_model().objects.create_student(
                    email=request.JSON['email'].lower(),
                )

        return Response(UserInitSerializer(user).data, status=200)


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

    @staticmethod
    def post(request):
        if request.user.is_authenticated() and not request.user.check_password(request.JSON['old_password']):
            return Response("Неверный пароль", status=404)
        request.user.set_password(request.JSON['new_password'])
        request.user.save()
        return Response("Пароль был изменён", status=200)


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

    @staticmethod
    def post(request):
        if not request.user.is_authenticated():
            user = auth.authenticate(email=request.JSON.get('email'), password=request.JSON.get('password'))
            try:
                auth.login(request, user)
            except AttributeError:
                return Response("Неверный пароль", status=404)
        return Response(UserInitSerializer(request.user).data, status=200)


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

    @staticmethod
    def post(request):
        if request.user.is_authenticated():
            auth.logout(request)
        return Response(status=204)


class UpdateProgress(APIView):
    """
    Переводит ученика на следующую стадию прохождения курса
    Запрос идёт синхронно возвращает id нового объекта прогресса
    """
    renderer_classes = (JSONRenderer,)

    @staticmethod
    def post(request):
        """
            На вход обязательно передаётся параметр id (id узла).
        """
        pk = int(request.JSON.get('id'))
        res_403 = Response('Permission denied', status=403)

        try:
            vertex = Vertex.objects.get(id=pk)
        except Vertex.DoesNotExist:
            return Response("Объект не найден", status=404)

        if vertex.content_type.model == 'task':
            return res_403

        try:
            next_vertex = vertex.get_next(['task', 'tutorial'])
        except ValueError:
            next_vertex = None

        try:
            progress = Progress.objects.get(user=request.user, course=vertex.course, active_obj=vertex)
            progress.active_obj = next_vertex

            if not next_vertex:
                progress.success = True

            if next_vertex.content_type.model == 'task':
                """
                  создание тредов для приёма домашки
                """
                teacher_thread = Thread.objects.get(
                    key="""user_%s""" % vertex.course.get_teacher().id,
                )

                user_thread = Thread.objects.get(
                    key="""user_%s""" % request.user.id,
                )

                support_thread = Thread.objects.get(
                    key="suports",
                )

                child_thread = Thread.objects.create(
                    key="""user_%s__vertex_%s""" % (request.user.id, vertex.id,),
                    text="""Домашняя работа по курсу %s и теме %s для студента %s""" %
                         (vertex.course.title, vertex.vertex_set.all()[0].title, request.user.get_full_name()),
                )

                child_thread.subscribers.add(request.user)
                child_thread.parent.add(teacher_thread)
                child_thread.parent.add(support_thread)
                child_thread.parent.add(user_thread)

            progress.save()
            return Response({'id': progress.active_obj.id, 'type': progress.active_obj.content_type.model}, status=200)
        except Progress.DoesNotExist:
            pass

        try:
            privilege = ExtraPrivilege.objects.get(user=request.user, subject=vertex)
            privilege.is_done = True
            privilege.save()
            return Response({'id': next_vertex.id, 'type': next_vertex.content_type.model}, status=200)
        except ExtraPrivilege.DoesNotExist:
            return res_403


class UserGuardView(APIView):
    renderer_classes = (JSONRenderer,)
    permission_classes = (IsAuthenticated,)

    @staticmethod
    def get(request, pk, page):
        try:
            user = get_user_model().objects.get(id=pk)
        except get_user_model().DoesNotExist:
            return Response("User doesn't exist", status=404)

        is_i = request.user == user
        res_403 = Response('Permission denied', status=403)
        res_204 = Response(status=204)

        if is_i and not request.user.groups.filter(name='teachers').exists() and page == 'homeworks':
            return res_403

        if is_i and not \
                request.user.groups.filter(name__in=['students', 'managers', 'lead_managers']).exists() \
                and page == 'payment':
            return res_403

        if is_i:
            return res_204

        if page == 'profile' and (request.user.is_superuser or request.user.is_staff):
            return res_204

        return res_403