Refactor cancelling positions and orders in the data model (#1088)

- [x] Data model
- [x] display in order view in backend
- [x] review all usages of OrderPositions.objects
- [x] review all usages of order.positions
- [x] review all other model usages
- [x] review plugins
- [x] plugins backwards-compatible API?
- [x] decide on way forward for REST API
- [x] need to cancel fees
- [x] tests
- [ ] plugins
  - [ ] gdpr
  - [ ] reports
- [x] docs

src/pretix/control/forms/filter.py

@@ -100,14 +100,13 @@ class OrderFilterForm(FilterForm):
         label=_('Order status'),
         choices=(
             ('', _('All orders')),
-            ('p', _('Paid')),
-            ('n', _('Pending')),
+            (Order.STATUS_PAID, _('Paid (or canceled with paid fee)')),
+            (Order.STATUS_PENDING, _('Pending')),
             ('o', _('Pending (overdue)')),
-            ('np', _('Pending or paid')),
-            ('e', _('Expired')),
-            ('ne', _('Pending or expired')),
-            ('c', _('Canceled')),
-            ('r', _('Refunded')),
+            (Order.STATUS_PENDING + Order.STATUS_PAID, _('Pending or paid')),
+            (Order.STATUS_EXPIRED, _('Expired')),
+            (Order.STATUS_PENDING + Order.STATUS_EXPIRED, _('Pending or expired')),
+            (Order.STATUS_CANCELED, _('Canceled')),
         ),
         required=False,
     )
@@ -201,14 +200,13 @@ class EventOrderFilterForm(OrderFilterForm):
         label=_('Order status'),
         choices=(
             ('', _('All orders')),
-            ('p', _('Paid')),
-            ('n', _('Pending')),
+            (Order.STATUS_PAID, _('Paid (or canceled with paid fee)')),
+            (Order.STATUS_PENDING, _('Pending')),
             ('o', _('Pending (overdue)')),
-            ('np', _('Pending or paid')),
-            ('e', _('Expired')),
-            ('ne', _('Pending or expired')),
-            ('c', _('Canceled')),
-            ('r', _('Refunded')),
+            (Order.STATUS_PENDING + Order.STATUS_PAID, _('Pending or paid')),
+            (Order.STATUS_EXPIRED, _('Expired')),
+            (Order.STATUS_PENDING + Order.STATUS_EXPIRED, _('Pending or expired')),
+            (Order.STATUS_CANCELED, _('Canceled')),
             ('pa', _('Approval pending')),
             ('overpaid', _('Overpaid')),
             ('underpaid', _('Underpaid')),
@@ -246,10 +244,10 @@ class EventOrderFilterForm(OrderFilterForm):
         qs = super().filter_qs(qs)
 
         if fdata.get('item'):
-            qs = qs.filter(positions__item=fdata.get('item'))
+            qs = qs.filter(all_positions__item=fdata.get('item'), all_positions__canceled=False)
 
         if fdata.get('subevent'):
-            qs = qs.filter(positions__subevent=fdata.get('subevent'))
+            qs = qs.filter(all_positions__subevent=fdata.get('subevent'), all_positions__canceled=False)
 
         if fdata.get('question') and fdata.get('answer') is not None:
             q = fdata.get('question')
@@ -278,8 +276,8 @@ class EventOrderFilterForm(OrderFilterForm):
 
         if fdata.get('status') == 'overpaid':
             qs = qs.filter(
-                Q(~Q(status__in=(Order.STATUS_REFUNDED, Order.STATUS_CANCELED)) & Q(pending_sum_t__lt=0))
-                | Q(Q(status__in=(Order.STATUS_REFUNDED, Order.STATUS_CANCELED)) & Q(pending_sum_rc__lt=0))
+                Q(~Q(status=Order.STATUS_CANCELED) & Q(pending_sum_t__lt=0))
+                | Q(Q(status=Order.STATUS_CANCELED) & Q(pending_sum_rc__lt=0))
             )
         elif fdata.get('status') == 'pendingpaid':
             qs = qs.filter(

src/pretix/control/forms/orders.py

@@ -367,8 +367,7 @@ class OrderRefundForm(forms.Form):
         required=False,
         widget=forms.RadioSelect,
         choices=(
-            ('mark_refunded', _('Mark the complete order as refunded. The order will be canceled and all tickets will '
-                                'no longer work. This can not be reverted.')),
+            ('mark_refunded', _('Cancel the order. All tickets will no longer work. This can not be reverted.')),
             ('mark_pending', _('Mark the order as pending and allow the user to pay the open amount with another '
                                'payment method.')),
             ('do_nothing', _('Do nothing and keep the order as it is.')),
@@ -391,7 +390,7 @@ class OrderRefundForm(forms.Form):
         self.order = kwargs.pop('order')
         super().__init__(*args, **kwargs)
         change_decimal_field(self.fields['partial_amount'], self.order.event.currency)
-        if self.order.status in (Order.STATUS_REFUNDED, Order.STATUS_CANCELED):
+        if self.order.status == Order.STATUS_CANCELED:
             del self.fields['action']
 
     def clean_partial_amount(self):