Display and manipulate cart

src/pretixbase/models.py

@@ -872,6 +872,9 @@ class ItemVariation(Versionable):
         verbose_name = _("Item variation")
         verbose_name_plural = _("Item variations")
 
+    def __str__(self):
+        return str(self.to_variation_dict())
+
     def delete(self, *args, **kwargs):
         super().delete(*args, **kwargs)
         if self.item:
@@ -1099,14 +1102,14 @@ class Quota(Versionable):
                 Q(variation__quotas__in=[self])
             )
         )
-        paid_orders = OrderPosition.objects.filter(
+        paid_orders = OrderPosition.objects.current.filter(
             Q(order__status=Order.STATUS_PAID)
             & quotalookup
         ).count()
         if paid_orders >= self.size:
             return Quota.AVAILABILITY_GONE, 0
 
-        pending_valid_orders = OrderPosition.objects.filter(
+        pending_valid_orders = OrderPosition.objects.current.filter(
             Q(order__status=Order.STATUS_PENDING)
             & Q(order__expires__gte=now())
             & quotalookup
@@ -1114,7 +1117,7 @@ class Quota(Versionable):
         if (paid_orders + pending_valid_orders) >= self.size:
             return Quota.AVAILABILITY_ORDERED, 0
 
-        valid_cart_positions = CartPosition.objects.filter(
+        valid_cart_positions = CartPosition.objects.current.filter(
             Q(expires__gte=now())
             & quotalookup
         ).count()

src/pretixpresale/static/pretixpresale/less/event.less

@@ -1,5 +1,4 @@
 .product-row {
-    padding: 10px 0;
     border-top: 1px solid @table-border-color;
 
     &.headline, &.simple {
@@ -25,7 +24,14 @@
             color: @alert-warning-text;
         }
     }
-    .price {
+}
+.cart-row, .product-row {
+    padding: 10px 0;
+
+    .count form {
+        display: inline;
+    }
+    .price, .count {
         text-align: center;
     }
     .price small,

src/pretixpresale/templates/pretixpresale/event/fragment_cart.html

@@ -0,0 +1,59 @@
+{% load i18n %}
+{% if cart %}
+    <div class="panel panel-primary">
+        <div class="panel-heading">
+            <h3 class="panel-title">{% trans "Your cart" %}</h3>
+        </div>
+        <div class="panel-body">
+            {% for line in cart %}
+                <div class="row-fluid cart-row">
+                    <div class="col-md-4 col-xs-6">
+                        <strong>{{ line.item }}</strong>
+                        {% if line.variation %}
+                            – {{ line.variation }}
+                        {% endif %}
+                    </div>
+                    <div class="col-md-3 col-xs-6 price">
+                        {{ event.currency }} {{ line.price|floatformat:2 }}
+                    </div>
+                    <div class="col-md-2 col-xs-6 count">
+                        <form action="{% url "presale:event.cart.remove" event=event.slug organizer=event.organizer.slug %}"
+                                method="post">
+                            {% csrf_token %}
+                            {% if line.variation %}
+                                <input type="hidden" name="variation_{{ line.item.identity }}_{{ line.variation.identity }}"
+                                        value="1" />
+                            {% else %}
+                                <input type="hidden" name="item_{{ line.item.identity }}"
+                                        value="1" />
+                            {% endif %}
+                            <button class="btn btn-mini btn-link"><i class="fa fa-minus"></i></button>
+                        </form>
+                        {{ line.count }}
+                        <form action="{% url "presale:event.cart.add" event=event.slug organizer=event.organizer.slug %}"
+                            method="post">
+                            {% csrf_token %}
+                            {% if line.variation %}
+                                <input type="hidden" name="variation_{{ line.item.identity }}_{{ line.variation.identity }}"
+                                    value="1" />
+                            {% else %}
+                                <input type="hidden" name="item_{{ line.item.identity }}"
+                                        value="1" />
+                            {% endif %}
+                            <button class="btn btn-mini btn-link"><i class="fa fa-plus"></i></button>
+                        </form>
+                    </div>
+                    <div class="col-md-3 col-xs-6 price">
+                        <strong>{{ event.currency }} {{ line.total|floatformat:2 }}</strong>
+                        {% if line.item.tax_rate %}
+                            <br /><small>{% blocktrans trimmed with rate=line.item.tax_rate %}
+                            incl. {{ rate }}% taxes
+                        {% endblocktrans %}</small>
+                        {% endif %}
+                    </div>
+                    <div class="clearfix"></div>
+                </div>
+            {% endfor %}
+        </div>
+    </div>
+{% endif %}

src/pretixpresale/templates/pretixpresale/event/index.html

@@ -2,6 +2,7 @@
 {% load i18n %}
 
 {% block content %}
+    {% include "pretixpresale/event/fragment_cart.html" with cart=cart event=request.event %}
     <form method="post"
             action="{% url "presale:event.cart.add" organizer=request.event.organizer.slug event=request.event.slug %}?next={{ request.path_info|urlencode }}">
         {% csrf_token %}

src/pretixpresale/urls.py

@@ -10,6 +10,7 @@ urlpatterns = patterns(
             'pretixpresale.views.event',
             url(r'^$', pretixpresale.views.event.EventIndex.as_view(), name='event.index'),
             url(r'^cart/add$', pretixpresale.views.cart.CartAdd.as_view(), name='event.cart.add'),
+            url(r'^cart/remove$', pretixpresale.views.cart.CartRemove.as_view(), name='event.cart.remove'),
         )
     )),
 )

src/pretixpresale/views/__init__.py

@@ -0,0 +1,57 @@
+import uuid
+from itertools import groupby
+
+from django.db.models import Q
+
+from pretixbase.models import CartPosition
+
+
+class CartMixin:
+    def get_session_key(self):
+        if 'cart_key' in self.request.session:
+            return self.request.session.get('cart_key')
+        key = str(uuid.uuid4())
+        self.request.session['cart_key'] = key
+        return key
+
+
+class CartDisplayMixin(CartMixin):
+
+    def get_cart(self):
+        qw = Q(session=self.get_session_key())
+        if self.request.user.is_authenticated():
+            qw |= Q(user=self.request.user)
+
+        cartpos = list(CartPosition.objects.current.filter(
+            qw & Q(event=self.request.event)
+        ).order_by(
+            'item', 'variation'
+        ).select_related(
+            'item', 'variation'
+        ).prefetch_related(
+            'variation__values', 'variation__values__prop'
+        ))
+
+        # Group items of the same variation
+        # We do this by list manipulations instead of a GROUP BY query, as
+        # Django is unable to join related models in a .values() query
+        def keyfunc(pos):
+            return pos.item_id, pos.variation_id, pos.price
+
+        cart = []
+        for k, g in groupby(sorted(cartpos, key=keyfunc), key=keyfunc):
+            g = list(g)
+            group = g[0]
+            group.count = len(g)
+            group.total = group.count * group.price
+            cart.append(group)
+
+        return cart
+
+
+class EventViewMixin:
+
+    def get_context_data(self, **kwargs):
+        context = super().get_context_data(**kwargs)
+        context['event'] = self.request.event
+        return context

src/pretixpresale/views/cart.py

@@ -1,18 +1,18 @@
 from datetime import timedelta
-import uuid
 
 from django.contrib import messages
 from django.core.urlresolvers import reverse
+from django.db.models import Q
 from django.shortcuts import redirect
 from django.utils.timezone import now
 from django.views.generic import View
 from django.utils.translation import ugettext_lazy as _
 
-from .event import EventViewMixin
 from pretixbase.models import Item, ItemVariation, Quota, CartPosition
+from pretixpresale.views import CartMixin, EventViewMixin
 
 
-class CartActionMixin:
+class CartActionMixin(CartMixin):
 
     def get_next_url(self):
         if "next" in self.request.GET and '://' not in self.request.GET:
@@ -29,16 +29,6 @@ class CartActionMixin:
     def get_failure_url(self):
         return self.get_next_url()
 
-    def get_session_key(self):
-        if 'cart_key' in self.request.session:
-            return self.request.session.get('cart_key')
-        key = str(uuid.uuid4())
-        self.request.session['cart_key'] = key
-        return key
-
-
-class CartAdd(EventViewMixin, CartActionMixin, View):
-
     def _items_from_post_data(self):
         """
         Parses the POST data and returns a list of tuples in the
@@ -65,6 +55,32 @@ class CartAdd(EventViewMixin, CartActionMixin, View):
             return False
         return items
 
+
+class CartRemove(EventViewMixin, CartActionMixin, View):
+
+    def post(self, *args, **kwargs):
+        items = self._items_from_post_data()
+        if not items:
+            return redirect(self.get_failure_url())
+        qw = Q(session=self.get_session_key())
+        if self.request.user.is_authenticated():
+            qw |= Q(user=self.request.user)
+
+        for item, variation, cnt in items:
+            cw = qw & Q(item_id=item)
+            if variation:
+                cw &= Q(variation_id=variation)
+            else:
+                cw &= Q(variation__isnull=True)
+            for cp in CartPosition.objects.current.filter(cw).order_by("-price")[:cnt]:
+                cp.delete()
+
+        messages.success(self.request, _('Your cart has been updated.'))
+        return redirect(self.get_success_url())
+
+
+class CartAdd(EventViewMixin, CartActionMixin, View):
+
     def post(self, *args, **kwargs):
         items = self._items_from_post_data()
         if not items:
@@ -79,19 +95,27 @@ class CartAdd(EventViewMixin, CartActionMixin, View):
         # Fetch items from the database
         items_cache = {
             i.identity: i for i
-            in Item.objects.filter(
+            in Item.objects.current.filter(
                 event=self.request.event,
                 identity__in=[i[0] for i in items]
             ).prefetch_related("quotas")
         }
         variations_cache = {
             v.identity: v for v
-            in ItemVariation.objects.filter(
+            in ItemVariation.objects.current.filter(
                 item__event=self.request.event,
                 identity__in=[i[1] for i in items if i[1] is not None]
             ).select_related("item", "item__event").prefetch_related("quotas", "values", "values__prop")
         }
 
+        # Extend this user's cart session to 30 minutes from now to ensure all items in the
+        # cart expire at the same time
+        qw = Q(session=self.get_session_key())
+        if self.request.user.is_authenticated():
+            qw |= Q(user=self.request.user)
+        CartPosition.objects.current.filter(
+            qw & Q(event=self.request.event)).update(expires=now() + timedelta(minutes=30))
+
         # Process the request itself
         msg_some_unavailable = False
         for i in items:

src/pretixpresale/views/event.py

@@ -1,15 +1,9 @@
 from django.db.models import Count
 from django.views.generic import TemplateView
+from pretixpresale.views import EventViewMixin, CartDisplayMixin
 
 
-class EventViewMixin:
+class EventIndex(EventViewMixin, CartDisplayMixin, TemplateView):
-    def get_context_data(self, **kwargs):
-        context = super().get_context_data(**kwargs)
-        context['event'] = self.request.event
-        return context
-
-
-class EventIndex(EventViewMixin, TemplateView):
     template_name = "pretixpresale/event/index.html"
 
     def get_context_data(self, **kwargs):
@@ -46,4 +40,6 @@ class EventIndex(EventViewMixin, TemplateView):
             (cat, [i for i in items if i.category_id == cat.identity])
             for cat in set([i.category for i in items])  # insert categories into a set for uniqueness
         ], key=lambda group: (group[0].position, group[0].pk))  # a set is unsorted, so sort again by category
+
+        context['cart'] = self.get_cart()
         return context