# -*- coding: utf-8 -*-
from decimal import Decimal
from django.contrib.auth.models import User
from django.db import models
from shop.cart.modifiers_pool import cart_modifiers_pool
from shop.models.productmodel import Product
class Cart(models.Model):
"""
This should be a rather simple list of items. Ideally it should be bound to
a session and not to a User is we want to let people buy from our shop
without having to register with us.
"""
# If the user is null, that means this is used for a session
user = models.OneToOneField(User, null=True, blank=True)
date_created = models.DateTimeField(auto_now_add=True)
last_updated = models.DateTimeField(auto_now=True)
class Meta:
app_label = 'shop'
def __init__(self, *args, **kwargs):
super(Cart, self).__init__(*args,**kwargs)
# That will hold things like tax totals or total discount
self.subtotal_price = Decimal('0.0')
self.total_price = Decimal('0.0')
self.extra_price_fields = [] # List of tuples (label, value)
def add_product(self,product, quantity=1):
"""
Adds a (new) product to the cart
"""
# Let's see if we already have an Item with the same product ID
if CartItem.objects.filter(cart=self).filter(product=product).exists():
cart_item = CartItem.objects.filter(cart=self).filter(product=product)[0]
cart_item.quantity = cart_item.quantity + int(quantity)
cart_item.save()
else:
cart_item = CartItem.objects.create(cart=self,quantity=quantity,product=product)
cart_item.save()
self.save() # to get the last updated timestamp
def update_quantity(self, cart_item_id, quantity):
"""
Updates the quantity for given cart item or deletes it if its quantity
reaches `0`
"""
cart_item = self.items.get(pk=cart_item_id)
52 if quantity == 0:
cart_item.delete()
else:
cart_item.quantity = quantity
cart_item.save()
self.save()
def delete_item(self, cart_item_id):
"""
A simple convenience method to delete one of the cart's items. This
allows to implicitely check for "access rights" since we insure the cartitem
is actually in the user's cart
"""
cart_item = self.items.get(pk=cart_item_id)
cart_item.delete()
self.save()
def update(self):
"""
This should be called whenever anything is changed in the cart (added or removed)
It will loop on all line items in the cart, and call all the price modifiers
on each row.
After doing this, it will compute and update the order's total and
subtotal fields, along with any payment field added along the way by
modifiers.
Note that theses added fields are not stored - we actually want to reflect
rebate and tax changes on the *cart* items, but we don't want that for
the order items (since they are legally binding after the "purchase" button
was pressed)
"""
items = CartItem.objects.filter(cart=self)
self.subtotal_price = Decimal('0.0') # Reset the subtotal
for item in items: # For each OrderItem (order line)...
self.subtotal_price = self.subtotal_price + item.update()
item.save()
# Now we have to iterate over the registered modifiers again (unfortunately)
# to pass them the whole Order this time
for modifier in cart_modifiers_pool.get_modifiers_list():
modifier.process_cart(self)
self.total_price = self.subtotal_price
# Like for line items, most of the modifiers will simply add a field
# to extra_price_fields, let's update the total with them
for label, value in self.extra_price_fields:
self.total_price = self.total_price + value
def empty(self):
"""
Remove all cart items
"""
self.items.all().delete()
self.delete()
@property
def total_quantity(self):
"""
Returns the total quantity of all items in the cart
"""
return sum([ci.quantity for ci in self.items.all()])
class CartItem(models.Model):
"""
This is a holder for the quantity of items in the cart and, obviously, a
pointer to the actual Product being purchased :)
"""
cart = models.ForeignKey(Cart, related_name="items")
quantity = models.IntegerField()
product = models.ForeignKey(Product)
class Meta:
app_label = 'shop'
def __init__(self, *args, **kwargs):
# That will hold extra fields to display to the user
# (ex. taxes, discount)
super(CartItem, self).__init__(*args,**kwargs)
self.extra_price_fields = [] # list of tuples (label, value)
# These must not be stored, since their components can be changed between
# sessions / logins etc...
self.line_subtotal = Decimal('0.0')
self.line_total = Decimal('0.0')
def update(self):
self.line_subtotal = self.product.get_price() * self.quantity
self.line_total = self.line_subtotal
for modifier in cart_modifiers_pool.get_modifiers_list():
# We now loop over every registered price modifier,
# most of them will simply add a field to extra_payment_fields
modifier.process_cart_item(self)
for label, value in self.extra_price_fields:
self.line_total = self.line_total + value
return self.line_total
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