# -*- coding: utf-8 -*-
from decimal import Decimal
from distutils.version import LooseVersion
from django.contrib.auth.models import User
from django.core.urlresolvers import reverse
from django.db import models
from django.db.models.aggregates import Sum
from django.utils.translation import ugettext_lazy as _
from polymorphic.polymorphic_model import PolymorphicModel
from shop.cart.modifiers_pool import cart_modifiers_pool
from shop.util.fields import CurrencyField
from shop.util.loader import get_model_string
import django
#==============================================================================
# Product
#==============================================================================
class BaseProduct(PolymorphicModel):
"""
A basic product for the shop
Most of the already existing fields here should be generic enough to reside
on the "base model" and not on an added property
"""
name = models.CharField(max_length=255, verbose_name=_('Name'))
slug = models.SlugField(verbose_name=_('Slug'), unique=True)
active = models.BooleanField(default=False, verbose_name=_('Active'))
date_added = models.DateTimeField(auto_now_add=True, verbose_name=_('Date added'))
last_modified = models.DateTimeField(auto_now=True, verbose_name=_('Last modified'))
unit_price = CurrencyField(verbose_name=_('Unit price'))
class Meta(object):
abstract = True
app_label = 'shop'
verbose_name = _('Product')
verbose_name_plural = _('Products')
def __unicode__(self):
return self.name
def get_absolute_url(self):
return reverse('product_detail', args=[self.slug])
def get_price(self):
"""
Return the price for this item (provided for extensibility)
"""
return self.unit_price
def get_name(self):
"""
Return the name of this Product (provided for extensibility)
"""
return self.name
#==============================================================================
# Carts
#==============================================================================
class BaseCart(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(object):
abstract = True
app_label = 'shop'
verbose_name = _('Cart')
verbose_name_plural = _('Carts')
def __init__(self, *args, **kwargs):
super(BaseCart, 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.current_total = Decimal('0.0') # used by cart modifiers
self.extra_price_fields = [] # List of tuples (label, value)
def add_product(self, product, quantity=1, merge=True, queryset=None):
"""
Adds a (new) product to the cart.
The parameter `merge`, controls wheter we should merge the added
CartItem with another already existing sharing the same
product_id. This is useful when you have products with variations
(for example), and you don't want to have your products merge (to loose
their specific variations, for example).
A drawback is, that generally setting `merge` to ``False`` for products
with variations can be a problem if users can buy thousands of products
at a time (that would mean we would create thousands of CartItems as
well which all have the same variation).
The parameter `queryset` can be used to override the standard queryset
that is being used to find the CartItem that should be merged into.
If you use variations, just finding the first CartItem that
belongs to this cart and the given product is not sufficient. You will
want to find the CartItem that already has the same variations that the
user chose for this request.
Example with merge = True:
>>> self.items[0] = CartItem.objects.create(..., product=MyProduct())
>>> self.add_product(MyProduct())
>>> self.items[0].quantity
2
Example with merge=False:
>>> self.items[0] = CartItem.objects.create(..., product=MyProduct())
>>> self.add_product(MyProduct())
>>> self.items[0].quantity
1
>>> self.items[1].quantity
1
"""
from shop.models import CartItem
if queryset == None:
queryset = CartItem.objects.filter(cart=self, product=product)
item = queryset
# Let's see if we already have an Item with the same product ID
if item.exists() and merge:
cart_item = item[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
return cart_item
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)
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, state=None):
"""
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)
"""
from shop.models import CartItem, Product
# This is a ghetto "select_related" for polymorphic models.
items = CartItem.objects.filter(cart=self)
product_ids = [item.product_id for item in items]
products = Product.objects.filter(id__in=product_ids)
products_dict = dict([(p.id, p) for p in products])
self.extra_price_fields = [] # Reset the price fields
self.subtotal_price = Decimal('0.0') # Reset the subtotal
# This will hold extra information that cart modifiers might want to pass
# to each other
if state == None:
state = {}
# This calls all the pre_proocess_cart methods (if any), before the cart
# is, well, processed. This allows for data collection on the cart for example)
for modifier in cart_modifiers_pool.get_modifiers_list():
modifier.pre_process_cart(self, state)
for item in items: # For each OrderItem (order line)...
item.product = products_dict[item.product_id] #This is still the ghetto select_related
self.subtotal_price = self.subtotal_price + item.update(state)
item.save()
self.current_total = self.subtotal_price
# 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, state)
self.total_price = self.current_total
# This calls the post_process_cart method from cart modifiers, if any.
# It allows for a last bit of processing on the "finished" cart, before
# it is displayed
for modifier in cart_modifiers_pool.get_modifiers_list():
modifier.post_process_cart(self, state)
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 BaseCartItem(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(get_model_string('Cart'), related_name="items")
quantity = models.IntegerField()
product = models.ForeignKey(get_model_string('Product'))
class Meta(object):
abstract = True
app_label = 'shop'
verbose_name = _('Cart item')
verbose_name_plural = _('Cart items')
def __init__(self, *args, **kwargs):
# That will hold extra fields to display to the user
# (ex. taxes, discount)
super(BaseCartItem, 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')
self.current_total = Decimal('0.0') # Used by cart modifiers
def update(self, state):
self.extra_price_fields = [] # Reset the price fields
self.line_subtotal = self.product.get_price() * self.quantity
self.current_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, state)
self.line_total = self.current_total
return self.line_total
#==============================================================================
# Orders
#==============================================================================
class BaseOrder(models.Model):
"""
A model representing an Order.
An order is the "in process" counterpart of the shopping cart, which holds
stuff like the shipping and billing addresses (copied from the User profile)
when the Order is first created), list of items, and holds stuff like the
status, shipping costs, taxes, etc...
"""
PROCESSING = 1 # New order, no shipping/payment backend chosen yet
PAYMENT = 2 # The user is filling in payment information
CONFIRMED = 3 # Chosen shipping/payment backend, processing payment
COMPLETED = 4 # Successful payment confirmed by payment backend
SHIPPED = 5 # successful order shipped to client
CANCELLED = 6 # order has been cancelled
STATUS_CODES = (
(PROCESSING, 'Processing'),
(PAYMENT, 'Selecting payment'),
(CONFIRMED, 'Confirmed'),
(COMPLETED, 'Completed'),
(SHIPPED, 'Shipped'),
(CANCELLED, 'Cancelled'),
)
# If the user is null, the order was created with a session
user = models.ForeignKey(User, blank=True, null=True,
verbose_name=_('User'))
status = models.IntegerField(choices=STATUS_CODES, default=PROCESSING,
verbose_name=_('Status'))
order_subtotal = CurrencyField(verbose_name=_('Order subtotal'))
order_total = CurrencyField(verbose_name='Order total')
shipping_address_text = models.TextField(_('Shipping address'), blank=True, null=True)
billing_address_text = models.TextField(_('Billing address'), blank=True, null=True)
created = models.DateTimeField(auto_now_add=True,
verbose_name=_('Created'))
modified = models.DateTimeField(auto_now=True,
verbose_name=_('Updated'))
class Meta(object):
abstract = True
app_label = 'shop'
verbose_name = _('Order')
verbose_name_plural = _('Orders')
def __unicode__(self):
return _('Order ID: %(id)s') % {'id': self.id}
def get_absolute_url(self):
return reverse('order_detail', kwargs={'pk': self.pk })
def is_payed(self):
"""Has this order been integrally payed for?"""
return self.amount_payed == self.order_total
def is_completed(self):
return self.status == self.COMPLETED
@property
def amount_payed(self):
"""
The amount payed is the sum of related orderpayments
"""
from shop.models import OrderPayment
sum = OrderPayment.objects.filter(order=self).aggregate(sum=Sum('amount'))
result = sum.get('sum')
if not result:
result = Decimal('-1')
return result
@property
def shipping_costs(self):
from shop.models import ExtraOrderPriceField
sum = Decimal('0.0')
cost_list = ExtraOrderPriceField.objects.filter(order=self).filter(is_shipping=True)
for cost in cost_list:
sum = sum + cost.value
return sum
def set_billing_address(self, billing_address):
"""
Process billing_address trying to get as_text method from address
and copying.
You can override this method to process address more granulary
e.g. you can copy address instance and save FK to it in your order class
"""
exit if hasattr(billing_address, 'as_text'):
self.billing_address_text = billing_address.as_text()
self.save()
def set_shipping_address(self, shipping_address):
"""
Process shipping_address trying to get as_text method from address
and copying.
You can override this method to process address more granulary
e.g. you can copy address instance and save FK to it in your order class
"""
exit if hasattr(shipping_address, 'as_text'):
self.shipping_address_text = shipping_address.as_text()
self.save()
# We need some magic to support django < 1.3 that has no support models.on_delete option
f_kwargs = {}
399if LooseVersion(django.get_version()) >= LooseVersion('1.3'):
f_kwargs['on_delete'] = models.SET_NULL
class BaseOrderItem(models.Model):
"""
A line Item for an order.
"""
order = models.ForeignKey(get_model_string('Order'), related_name='items',
verbose_name=_('Order'))
product_reference = models.CharField(max_length=255,
verbose_name=_('Product reference'))
product_name = models.CharField(max_length=255, null=True, blank=True,
verbose_name=_('Product name'))
product = models.ForeignKey(get_model_string('Product'), verbose_name=_('Product'), null=True, blank=True, **f_kwargs)
unit_price = CurrencyField(verbose_name=_('Unit price'))
quantity = models.IntegerField(verbose_name=_('Quantity'))
line_subtotal = CurrencyField(verbose_name=_('Line subtotal'))
line_total = CurrencyField(verbose_name=_('Line total'))
class Meta(object):
abstract = True
app_label = 'shop'
verbose_name = _('Order item')
verbose_name_plural = _('Order items')
def save(self, *args, **kwargs):
if self.product:
self.product_name = self.product.name
super(BaseOrderItem, self).save(*args, **kwargs)
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