"""News app models."""
from django.db import models
from django.contrib.contenttypes import fields as generic
from django.utils import timezone
from django.utils.translation import gettext_lazy as _
from rest_framework.reverse import reverse
from utils.models import BaseAttributes, TJSONField, TranslatedFieldsMixin
from random import sample as random_sample


class NewsType(models.Model):
    """NewsType model."""

    name = models.CharField(_('name'), max_length=250)

    class Meta:
        """Meta class."""

        verbose_name_plural = _('news types')
        verbose_name = _('news type')

    def __str__(self):
        """Overrided __str__ method."""
        return self.name


class NewsQuerySet(models.QuerySet):
    """QuerySet for model News"""

    def by_type(self, news_type):
        """Filter News by type"""
        return self.filter(news_type__name=news_type)

    def by_country_code(self, code):
        """Filter collection by country code."""
        return self.filter(country__code=code)

    def published(self):
        """Return only published news"""
        now = timezone.now()
        return self.filter(models.Q(models.Q(end__gte=now) |
                                    models.Q(end__isnull=True)),
                           state__in=self.model.PUBLISHED_STATES, start__lte=now)

    def with_related(self):
        """Return qs with related objects."""
        return self.select_related('news_type', 'country').prefetch_related('tags')


class News(BaseAttributes, TranslatedFieldsMixin):
    """News model."""

    STR_FIELD_NAME = 'title'

    # TEMPLATE CHOICES
    NEWSPAPER = 0
    MAIN_PDF_ERB = 1
    MAIN = 2

    TEMPLATE_CHOICES = (
        (NEWSPAPER, 'newspaper'),
        (MAIN_PDF_ERB, 'main.pdf.erb'),
        (MAIN, 'main'),
    )

    # STATE CHOICES
    WAITING = 0
    HIDDEN = 1
    PUBLISHED = 2
    PUBLISHED_EXCLUSIVE = 3

    PUBLISHED_STATES = [PUBLISHED, PUBLISHED_EXCLUSIVE]

    STATE_CHOICES = (
        (WAITING, _('Waiting')),
        (HIDDEN, _('Hidden')),
        (PUBLISHED, _('Published')),
        (PUBLISHED_EXCLUSIVE, _('Published exclusive')),
    )

    news_type = models.ForeignKey(NewsType, on_delete=models.PROTECT,
                                  verbose_name=_('news type'))
    title = TJSONField(blank=True, null=True, default=None,
                       verbose_name=_('title'),
                       help_text='{"en-GB":"some text"}')
    subtitle = TJSONField(blank=True, null=True, default=None,
                          verbose_name=_('subtitle'),
                          help_text='{"en-GB":"some text"}')
    description = TJSONField(blank=True, null=True, default=None,
                             verbose_name=_('description'),
                             help_text='{"en-GB":"some text"}')
    start = models.DateTimeField(verbose_name=_('Start'))
    end = models.DateTimeField(blank=True, null=True, default=None,
                               verbose_name=_('End'))
    slug = models.SlugField(unique=True, max_length=50,
                            verbose_name=_('News slug'))
    playlist = models.IntegerField(_('playlist'))

    # author = models.CharField(max_length=255, blank=True, null=True,
    #                           default=None,verbose_name=_('Author'))

    state = models.PositiveSmallIntegerField(default=WAITING, choices=STATE_CHOICES,
                                             verbose_name=_('State'))
    author = models.CharField(max_length=255, blank=True, null=True,
                              default=None,verbose_name=_('Author'))

    is_highlighted = models.BooleanField(default=False,
                                         verbose_name=_('Is highlighted'))
    # TODO: metadata_keys - описание ключей для динамического построения полей метаданных
    # TODO: metadata_values - Описание значений для динамических полей из MetadataKeys
    image_url = models.URLField(blank=True, null=True, default=None,
                                verbose_name=_('Image URL path'))
    preview_image_url = models.URLField(blank=True, null=True, default=None,
                                        verbose_name=_('Preview image URL path'))
    template = models.PositiveIntegerField(choices=TEMPLATE_CHOICES, default=NEWSPAPER)
    address = models.ForeignKey('location.Address', blank=True, null=True,
                                default=None, verbose_name=_('address'),
                                on_delete=models.SET_NULL)
    country = models.ForeignKey('location.Country', blank=True, null=True,
                                on_delete=models.SET_NULL,
                                verbose_name=_('country'))
    tags = generic.GenericRelation(to='main.MetaDataContent')

    objects = NewsQuerySet.as_manager()

    class Meta:
        """Meta class."""

        verbose_name = _('news')
        verbose_name_plural = _('news')

    def __str__(self):
        return f'news: {self.slug}'

    @property
    def is_publish(self):
        return self.state in self.PUBLISHED_STATES

    @property
    def web_url(self):
        return reverse('web:news:rud', kwargs={'slug': self.slug})

    @property
    def list_also_like_news(self):

        # without "distinct" method the doubles are arising
        like_news = News.objects.published().filter(news_type=self.news_type, tags__in=models.F("tags"))\
            .exclude(id=self.id).distinct()

        news_count = like_news.count()

        if news_count >= 6:
            random_ids = random_sample(range(news_count), 6)
        else:
            random_ids = random_sample(range(news_count), news_count)

        news_list = [{"id": like_news[r].id, "slug": like_news[r].slug} for r in random_ids]

        return news_list

    @property
    def same_theme(self):
        # on the same theme news

        # without "distinct" method the doubles are arising
        like_news = News.objects.published().filter(news_type=self.news_type, tags__in=models.F("tags"))\
            .order_by("-start").exclude(id=self.id).distinct()

        news_count = like_news.count()

        if news_count >= 3:
            like_news = like_news[:3]

        news_list = [{"id": n.id, "slug": n.slug} for n in like_news]

        return news_list

    @property
    def should_read(self):
        # you should read news

        # without "distinct" method the doubles are arising
        like_news = News.objects.published().filter(news_type=self.news_type).exclude(id=self.id).distinct()

        news_count = like_news.count()

        if news_count >= 3:
            random_ids = random_sample(range(news_count), 3)
        else:
            random_ids = random_sample(range(news_count), news_count)

        news_list = [{"id": like_news[r].id, "slug": like_news[r].slug} for r in random_ids]

        return news_list