from rest_framework.decorators import action
from rest_framework.response import Response
from rest_framework import viewsets, mixins, status
from rest_framework.authentication import TokenAuthentication
from rest_framework.permissions import IsAuthenticated, \
                                       IsAuthenticatedOrReadOnly

from core.models import Tag, Ingredient, Recipe
from recipe import serializers


class BaseRecipeAttrViewSet(viewsets.GenericViewSet,
                            mixins.ListModelMixin,
                            mixins.CreateModelMixin):
    authentication_classes = (TokenAuthentication,)
    permission_classes = (IsAuthenticated,)

    def get_queryset(self):
        """Return object of authenticated user"""
        assigned_only = bool(
            int(self.request.query_params.get('assigned_only', 0))
        )
        queryset = self.queryset
        if assigned_only:
            queryset = queryset.filter(recipe__isnull=False)

        return queryset.filter(
                user=self.request.user
            ).order_by('-name').distinct()

    def perform_create(self, serializer):
        """Create a new object"""
        serializer.save(user=self.request.user)


class TagViewSet(BaseRecipeAttrViewSet):
    """Manage tags in the database"""
    queryset = Tag.objects.all()
    serializer_class = serializers.TagSerializer


class IngredientViewSet(BaseRecipeAttrViewSet):
    """Manage ingredents in the database"""
    queryset = Ingredient.objects.all()
    serializer_class = serializers.IngredientSerializer


class RecipeViewSet(viewsets.ModelViewSet):
    """manage recipes in the database"""
    queryset = Recipe.objects.all()
    serializer_class = serializers.RecipeSerializer
    authentication_classes = (TokenAuthentication,)
    permission_classes = (IsAuthenticatedOrReadOnly,)

    def _params_to_ints(self, qs):
        """Convert a list os string IDs to alist of integers"""
        return [int(str_id) for str_id in qs.split(',')]

    def get_queryset(self):
        """Retrieve the recipes for the auth user"""
        tags = self.request.query_params.get('tags')
        ingredients = self.request.query_params.get('ingredients')
        queryset = self.queryset
        if tags:
            tag_ids = self._params_to_ints(tags)
            queryset = queryset.filter(tags__id__in=tag_ids)

        if ingredients:
            ingredients_ids = self._params_to_ints(ingredients)
            queryset = queryset.filter(ingredients__id__in=ingredients_ids)

        return queryset.order_by('-id')

    def get_serializer_class(self):
        """Return apropiate serializer class"""
        if self.action == 'retrieve':
            return serializers.RecipeDetailSerializer
        elif self.action == 'upload_image':
            return serializers.RecipeImageSerializer

        return self.serializer_class

    def perform_create(self, serializer):
        """Create a new recipe"""
        serializer.save(user=self.request.user)

    @action(methods=['POST'], detail=True, url_path='upload-image')
    def upload_image(self, request, pk=None):
        """Upload a image recipe"""
        recipe = self.get_object()
        serializer = self.get_serializer(
            recipe,
            data=request.data
        )

        if serializer.is_valid():
            serializer.save()
            return Response(
                serializer.data,
                status=status.HTTP_200_OK
            )

        return Response(
            serializer.errors,
            status=status.HTTP_400_BAD_REQUEST
        )
