class Product(models.Model):

    name = models.CharField(max_length=150)
    slug = models.SlugField(max_length=150, db_index=True, unique=True)
    price = models.IntegerField(verbose_name='price')
    category = models.ForeignKey(Category, related_name='category', verbose_name='category',
                                 on_delete=models.CASCADE, default='0')

    size = models.ManyToManyField(Size, related_name='size', verbose_name='size',
                                  blank=True)

    color = models.ManyToManyField(Color, related_name='color', verbose_name='color',
                                blank=True)

    sale = models.ForeignKey(Sale, related_name='sale',
                                null=True, blank=True, verbose_name='sale',
                                on_delete=models.SET_NULL)

    image = models.ImageField(upload_to='media/img/', default='Null', blank=True, null=True)
    created_at = models.DateTimeField(auto_now_add=True, verbose_name='created')

    class Meta:
        ordering = ('name', 'created_at',)
        index_together = ('id', 'slug')
        verbose_name = 'product'
        verbose_name_plural = 'products'

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse('product_detail', kwargs={'category_slug': self.category.slug,
                                                          'slug': self.slug})
    def has_sale(self):
        return self.sale

    def calculate_price(self):
        if self.sale:
            return self.price - (self.price * self.sale.percent * 0.01)
        else:
            return self.price

    def is_new(self):
        new_days = 14
        now = datetime.now(tz=timezone.utc)
        return now - self.created_at < timedelta(days=new_days)