from rest_framework import viewsets, permissions, status
from .serializers import *
from django_auth_ldap.backend import LDAPBackend
from rest_framework.decorators import action
from rest_framework.response import Response
from rest_framework.generics import get_object_or_404
from rest_framework import mixins
from .models import *

class SelfViewSet(mixins.ListModelMixin, viewsets.GenericViewSet):
    permission_classes = [permissions.IsAuthenticated]
    serializer_class = UserSerializer

    def list(self, request, format=None):
        # This is a bit stupid: we have a user, we create a queryset by
        # matching on the username. But I don't know a "nicer" way.
        # Nico, 2020-03-18
        user = get_user_model().objects.get(
                username=self.request.user.username)
        serializer = self.get_serializer(user, context = {'request': request})
        return Response(serializer.data)

class UserViewSet(viewsets.ReadOnlyModelViewSet):
    permission_classes = [permissions.IsAdminUser]

    def get_serializer_class(self):
        if self.action == 'import_from_ldap':
            return ImportUserSerializer
        else:
            return UserSerializer

    def get_queryset(self):
        return User.objects.all()

    # Override default implementation to search by username instead of ID.
    def retrieve(self, request, pk):
        queryset = self.filter_queryset(self.get_queryset())
        instance = get_object_or_404(queryset, username=pk)
        serializer = self.get_serializer(instance)

        return Response(serializer.data)

    @action(detail=False, methods=['post'], url_path='import_from_ldap')
    def import_from_ldap(self, request, pk=None):
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        ldap_username = serializer.validated_data.pop("username")
        user = LDAPBackend().populate_user(ldap_username)

        return Response(UserSerializer(user, context = {'request': request}).data)