from datetime import datetime
from math import floor

from django.core.cache import cache
from django.core.exceptions import ValidationError
from django.db import models
from django.db.models import Sum
from django.templatetags.static import static
from django.urls import reverse
from django.utils.text import slugify

from gallery.models.location import Location


class Album(models.Model):
    name = models.CharField(max_length=150, unique=True, verbose_name="Album")
    slug = models.SlugField(max_length=150, unique=True, verbose_name="Slug")
    location = models.ForeignKey(Location, blank=True, null=True, on_delete=models.SET_NULL, related_name='albums', verbose_name="Location")
    album_date = models.DateField(default=datetime.now, verbose_name="Album Date")
    cover = models.ForeignKey("Photo", blank=True, null=True, on_delete=models.SET_NULL, related_name='cover_to', verbose_name="Album cover")
    is_public = models.BooleanField(default=False, verbose_name="Published")

    def _cache_key(self, suffix):
        return f'album_{self.pk}_{suffix}'

    @property
    def photos_in_album(self):
        key = self._cache_key('photo_count')
        count = cache.get(key)

        if count is None:
            count = self.photos.count()
            cache.set(key, count, 60 * 60 * 24)  # Cache 24 h

        return count

    @property
    def photos_views(self):
        key = self._cache_key('photo_views')
        views = cache.get(key)

        if views is None:
            views = self.photos.aggregate(total_views=Sum('views'))['total_views'] or 0
            cache.set(key, views, 60 * 5)  # Cache 5 min

        return views

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.name)
        super(Album, self).save(*args, **kwargs)

    def get_absolute_url(self):
        return reverse('gallery:album_url', kwargs={'album_slug': self.slug})

    class Meta:
        verbose_name_plural = "Albums"
        ordering = ('album_date',)

    def __str__(self):
        return '{}'.format(self.name)