"""Filters from application News"""
from django.core.validators import EMPTY_VALUES
from django.utils.translation import gettext_lazy as _
from django_filters import rest_framework as filters
from rest_framework.serializers import ValidationError

from news import models


class NewsListFilterSet(filters.FilterSet):
    """FilterSet for News list"""

    is_highlighted = filters.BooleanFilter()
    title = filters.CharFilter(method='by_title')
    tag_group = filters.ChoiceFilter(
        choices=(
            (models.News.RECIPES_TAG_VALUE, _('Recipes')),
        ),
        method='by_tag_group'
    )
    tag_value__exclude = filters.CharFilter(method='exclude_tags')
    tag_value__in = filters.CharFilter(method='in_tags')
    type = filters.CharFilter(method='by_type')

    state = filters.NumberFilter()

    state__in = filters.CharFilter(method='by_states_list')

    SORT_BY_CREATED_CHOICE = "created"
    SORT_BY_START_CHOICE = "start"
    SORT_BY_CHOICES = (
        (SORT_BY_CREATED_CHOICE, "created"),
        (SORT_BY_START_CHOICE, "start"),
    )
    sort_by = filters.ChoiceFilter(method='sort_by_field', choices=SORT_BY_CHOICES)
    search = filters.CharFilter(method='search_news')

    class Meta:
        """Meta class"""
        model = models.News
        fields = (
            'title',
            'is_highlighted',
            'tag_group',
            'tag_value__exclude',
            'tag_value__in',
            'state',
            'sort_by',
            'search',
        )

    def search_news(self, queryset, name, value):
        if value not in EMPTY_VALUES:
            if len(value) < 3:
                raise ValidationError({'detail': _('Type at least 3 characters to search please.')})
            return queryset.es_search(value, relevance_order='ordering' not in self.request.query_params)
        return queryset

    def by_states_list(self, queryset, name, value):
        states = value.split('__')
        return queryset.filter(state__in=states)

    def in_tags(self, queryset, name, value):
        tags = value.split('__')
        return queryset.filter(tags__value__in=tags)

    def exclude_tags(self, queryset, name, value):
        tags = value.split('__')
        return queryset.exclude(tags__value__in=tags)

    def by_tag_group(self, queryset, name, value):
        if value == models.News.RECIPES_TAG_VALUE:
            queryset = queryset.recipe_news()
        return queryset

    def by_title(self, queryset, name, value):
        """Crappy search by title according to locale"""
        if value:
            locale = self.request.locale
            filters = {f'{name}__{locale}__icontains': value}
            return queryset.filter(**filters)
        else:
            return queryset

    def by_type(self, queryset, name, value):
        if value:
            return queryset.filter(news_type__name=value)
        else:
            return queryset

    def sort_by_field(self, queryset, name, value):
        if value == self.SORT_BY_START_CHOICE:
            return queryset.order_by('-publication_date', '-publication_time')
        return queryset.order_by(f'-{value}')