import csv
import datetime
import random
import string

from django.contrib import auth
from django.contrib.auth import get_user_model
from django.core.exceptions import ValidationError
from django.core.mail import send_mail
from django.db.models import Q
from django.http import HttpResponse
from django.shortcuts import redirect
from rest_framework.permissions import IsAuthenticated
from rest_framework.renderers import JSONRenderer
from rest_framework.response import Response
from rest_framework.views import APIView

from access.models.other import Invite, ResetPassword
from access.serializers import UserSelfSerializer, UserSearchSerializer
from courses.api import CourseProgressApi


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 ResetPasswordView(APIView):
    renderer_classes = (JSONRenderer,)

    @staticmethod
    def get(request):
        hash_key = request.GET.get('hash', None)
        if not hash_key:
            return Response("Нужно указать ключ", status=400)

        try:
            invite = ResetPassword.objects.get(hash=hash_key)
        except ResetPassword.DoesNotExist:
            return Response("Приглашение не найдено", status=404)

        if invite.date < datetime.datetime.now():
            invite.delete()
            return Response("Приглашение сгорело", status=403)

        invite.owner.set_password(invite.password)
        invite.owner.save()
        auth.login(request, invite.owner)
        invite.delete()
        return redirect('/')

    @staticmethod
    def post(request):
        if not request.user.is_authenticated():
            email = request.JSON.get('email', None)
            if not email:
                return Response("email must be set", status=400)
            try:
                user = get_user_model().objects.get(email=email)
                try:
                    invite = ResetPassword.objects.get(owner=user)
                    if invite.date < datetime.datetime.now():
                        return Response("Old invite has effect", status=403)
                    invite.delete()
                except ResetPassword.DoesNotExist:
                    pass

                invite = ResetPassword.objects.create(
                    owner=user,
                    hash=''.join(random.choice(string.ascii_letters) for _x in range(15)),
                    password=''.join(random.choice(string.ascii_letters) for _x in range(8)),
                    date=datetime.datetime.now() + datetime.timedelta(minutes=5)
                )
                send_mail(
                    subject="Сброс пароля",
                    message='''
                        Ваш новый пароль %s, (в последствии вы сможите сменить его в личном кабинете),
                        если вы не отправляли заявку на сброс пароля просто проигнорируйте это сообщение,
                        для подтверждения смены пароля перейдите по https://go.skillbox.ru/api/v1/users/reset/?hash=%s
                        (ссылке ссылка действительна в течении 5 минут)''' % (invite.password, invite.hash),
                    from_email='robo@skillbox.ru',
                    recipient_list=[user.email],
                )
                return Response(status=204)
            except get_user_model().DoesNotExist:
                return Response("user doesn't exist", status=404)


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

    def get(self, request):
        if request.user.is_authenticated() and \
                (request.user.is_superuser
                 or request.user.groups.filter(name__in=['managers', 'lead_managers']).exists()):

            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,)

    @staticmethod
    def get(request, pk=None):
        if pk is None:
            if request.user.is_authenticated():
                serialized_user = UserSelfSerializer(request.user).data
                serialized_user['is_i'] = True
                return Response(serialized_user, status=200)
            return Response('anonymous', status=200)

        if request.user.is_authenticated() and request.user.is_superuser \
                or request.user.is_staff or request.user.out_key == pk:

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

            serialized_user = UserSelfSerializer(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(UserSelfSerializer(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=400)
        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):
        password = request.JSON.get('password')
        email = request.JSON.get('email').lower()
        user = None
        if not request.user.is_authenticated():
            if not password == "skillbox":
                user = auth.authenticate(email=email, password=request.JSON.get('password'))
            else:
                try:
                    user = get_user_model().objects.get(email=email)
                except get_user_model().DoesNotExist:
                    return Response("User doesn't exist", status=404)

            try:
                auth.login(request, user)
            except AttributeError:
                return Response("Неверный пароль", status=404)

        serialized_user = UserSelfSerializer(user).data
        serialized_user['is_i'] = True

        return Response(serialized_user, 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 UserGuardView(APIView):
    renderer_classes = (JSONRenderer,)
    permission_classes = (IsAuthenticated,)

    @staticmethod
    def get(request, pk, page):
        try:
            user = get_user_model().objects.get(out_key=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


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

    @staticmethod
    def get(request, out_key):
        try:
            return Response(UserSearchSerializer(get_user_model().objects.get(out_key=out_key)).data, status=200)
        except get_user_model().DoesNotExist:
            return Response("User not found", status=404)