Added basket warnings.

When an item's price has changed, a warning is now displayed.

oscar/apps/basket/abstract_models.py

@@ -7,6 +7,7 @@ from django.utils.translation import ugettext as _
 from django.core.exceptions import ObjectDoesNotExist, PermissionDenied
 
 from oscar.apps.basket.managers import OpenBasketManager, SavedBasketManager
+from oscar.templatetags.currency_filters import currency
 
 # Basket statuses
 # - Frozen is for when a basket is in the process of being submitted
@@ -84,7 +85,7 @@ class AbstractBasket(models.Model):
         if not self.id:
             self.save()
 
-        # Line refernene is used to distinguish between variations of the same 
+        # Line reference is used to distinguish between variations of the same 
         # product (eg T-shirts with different personalisations)
         line_ref = self._create_line_reference(product, options)
 
@@ -513,6 +514,28 @@ class AbstractLine(models.Model):
             d = "%s (%s)" % (d.decode('utf-8'), ", ".join(ops))
         return d
 
+    def get_warning(self):
+        """
+        Return a warning message about this basket line if one is applicable
+
+        This could be things like the price has changed
+        """
+        if not self.price_incl_tax:
+            return
+        current_price_incl_tax = self.product.stockrecord.price_incl_tax
+        if current_price_incl_tax > self.price_incl_tax:
+            msg = u"The price of '%(product)s' has increased from %(old_price)s " \
+                  u"to %(new_price)s since you added it to your basket"
+            return _(msg % {'product': self.product.get_title(),
+                            'old_price': currency(self.price_incl_tax),
+                            'new_price': currency(current_price_incl_tax)})
+        if current_price_incl_tax < self.price_incl_tax:
+            msg = u"The price of '%(product)s' has decreased from %(old_price)s " \
+                  u"to %(new_price)s since you added it to your basket"
+            return _(msg % {'product': self.product.get_title(),
+                            'old_price': currency(self.price_incl_tax),
+                            'new_price': currency(current_price_incl_tax)})
+
 
 class AbstractLineAttribute(models.Model):
     """An attribute of a basket line"""

oscar/apps/basket/forms.py

@@ -40,7 +40,7 @@ class BasketLineForm(forms.ModelForm):
 
     class Meta:
         model = Line
-        exclude = ('basket', 'product', 'line_reference', )
+        exclude = ('basket', 'product', 'line_reference', 'price_incl_tax')
 
 
 class SavedLineForm(forms.ModelForm):

oscar/apps/basket/views.py

@@ -33,6 +33,17 @@ class BasketView(ModelFormSetView):
     def get_default_shipping_method(self, basket):
         return Repository().get_default_shipping_method(self.request.user, self.request.basket)
 
+    def get_basket_warnings(self, basket):
+        """
+        Return a list of warnings that apply to this basket
+        """
+        warnings = []
+        for line in basket.lines.all():
+            warning = line.get_warning()
+            if warning:
+                warnings.append(warning)
+        return warnings
+
     def get_context_data(self, **kwargs):
         context = super(BasketView, self).get_context_data(**kwargs)
         context['voucher_form'] = BasketVoucherForm()
@@ -40,6 +51,7 @@ class BasketView(ModelFormSetView):
         context['shipping_method'] = method
         context['shipping_charge_incl_tax'] = method.basket_charge_incl_tax()
         context['order_total_incl_tax'] = self.request.basket.total_incl_tax + method.basket_charge_incl_tax()
+        context['basket_warnings'] = self.get_basket_warnings(self.request.basket)
 
         if self.request.user.is_authenticated():
             try:
@@ -78,6 +90,7 @@ class BasketView(ModelFormSetView):
 
     def formset_invalid(self, formset):
         messages.info(self.request, _("There was a problem updating your basket, please check that all quantities are numbers"))
+        assert False
         return super(BasketView, self).formset_invalid(formset)
 
 

oscar/static/oscar/css/styles.css

@@ -1651,13 +1651,6 @@ button.btn.small, input[type="submit"].btn.small {
   -webkit-border-radius: 4px;
   -moz-border-radius: 4px;
   border-radius: 4px;
-  /*  Position alerts at the bottom of the browser window*/
-
-  position: fixed;
-  bottom: 0;
-  right: 2em;
-  width: 200px;
-  z-index: 9;
 }
 .alert, .alert-heading {
   color: #c09853;

oscar/templates/basket/basket.html

@@ -34,9 +34,17 @@ Basket | {{ block.super }}
 </div>
 {% endblock header %}
 
+
 {% block content %}
 
-{% if request.basket.lines.count %}
+{% if basket_warnings %}
+	<h5>Important messages about items in your basket</h5>
+	{% for warning in basket_warnings %}
+	<div class="alert">{{ warning }}</div>
+	{% endfor %}
+{% endif %}
+
+{% if not basket.is_empty %}
 
 <form action="." method="post" class="basket_summary" id="basket_formset">
     {% csrf_token %}

oscar/templatetags/currency_filters.py

@@ -20,9 +20,10 @@ def currency(value):
     symbol = getattr(settings, 'CURRENCY_SYMBOL', None)
     try:
         if symbol:
-            return "%s%s" % (symbol, locale.format("%.2f", value, grouping=True))
+            return u"%s%s" % (symbol, locale.format("%.2f", value, grouping=True))
         else:
-            return locale.currency(value, symbol=True, grouping=True)
+            c = locale.currency(value, symbol=True, grouping=True)
+            return unicode(c, 'utf8')
     except TypeError:
         return ''