from django_filters import rest_framework as filters

from recipes.models import Recipe


class RecipeFilter(filters.FilterSet):
    author = filters.AllValuesMultipleFilter(
        field_name='author__id')
    tags = filters.AllValuesMultipleFilter(
        field_name='tags__slug')
    is_favorited = filters.BooleanFilter(
        method='is_favorited_filter')
    is_in_shopping_cart = filters.BooleanFilter(
        method='is_in_shopping_cart_filter'
    )

    class Meta:
        model = Recipe
        fields = (
            'author',
            'tags',
            'is_favorited',
            'is_in_shopping_cart',
        )

    def is_favorited_filter(self, queryset, name, value):
        if value:
            user = self.request.user
            return queryset.filter(favorites__user_id=user.id)
        return queryset

    def is_in_shopping_cart_filter(self, queryset, name, value):
        if value:
            user = self.request.user
            return queryset.filter(shopping_list__user_id=user.id)
        return queryset

# Настройки Пагинации:
REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': (
        'rest_framework.permissions.IsAuthenticatedOrReadOnly',
    ),
    'DEFAULT_AUTHENTICATION_CLASSES': (
        'rest_framework.authentication.TokenAuthentication',
    ),
    'DEFAULT_FILTER_BACKENDS': (
        'django_filters.rest_framework.DjangoFilterBackend',
    ),
    'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
    'PAGE_SIZE': 6,
}