class Cycle(models.Model):
    STARS = (
        (1, 'one'),
        (2, 'two'),
        (3, 'three'),
        (4, 'four'),
        (5, 'five'),
    )

    category = models.ForeignKey(Category, related_name='cycle', on_delete=models.CASCADE)
    supplier = models.ForeignKey(Supplier, on_delete=models.CASCADE)
    name = models.CharField(max_length=120, db_index=True)
    slug = models.SlugField(max_length=120, db_index=True)
    image = models.ImageField(upload_to='upload/cycle/%Y/%m/%d', blank=True)
    description = models.TextField(blank=True)
    price = models.DecimalField(max_digits=10, decimal_places=2)
    stock = models.PositiveIntegerField()
    vote = models.SmallIntegerField(choices=STARS, default=5)
    available = models.BooleanField(default=True)
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)

    class Meta:
        ordering = ('name', )
        verbose_name = 'Cycle'
        verbose_name_plural = 'Cycles'

    def __str__(self):
        return self.name



class Cart(models.Model):
    user = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, blank=True, on_delete=models.CASCADE)
    items = models.ManyToManyField(Cycle, through='CartItem')
    timestamp = models.DateTimeField(auto_now_add=True, auto_now=False)
    updated = models.DateTimeField(auto_now_add=False, auto_now=True)
    subtotal = models.DecimalField(max_digits=50, decimal_places=2, default=0.00)
    tax_percentage = models.DecimalField(max_digits=10, decimal_places=5, default=0.085)
    tax_total = models.DecimalField(max_digits=50, decimal_places=2, default=0.00)
    total = models.DecimalField(max_digits=50, decimal_places=2, default=0.00)
    active = models.BooleanField(default=True)
    objects = CartManager()

    class Meta:
        verbose_name = 'Cart'
        verbose_name_plural = 'Carts'

    def __str__(self):
        return str(self.id)

    def update_total(self):
        subtotal = 0
        items = self.cartitem_set.all()
        for item in items:
            subtotal += item.line_item_total
        self.subtotal = '%.2f'%(subtotal)
        self.save()

    def is_complete(self):
        self.active = False
        self.save()



class CartItem(models.Model):
    cart = models.ForeignKey(Cart, on_delete=models.CASCADE)
    item = models.ForeignKey(Cycle, on_delete=models.CASCADE)
    quantity = models.PositiveIntegerField(default=1)
    line_item_total = models.DecimalField(max_digits=10, decimal_places=2)

    class Meta:
        verbose_name = 'Cart Item'
        verbose_name_plural = 'Cart Items'