Fix #782 -- Select2 widget for item selection for vouchers

src/pretix/control/forms/vouchers.py

@@ -1,20 +1,25 @@
 import copy
 
 from django import forms
-from django.core.exceptions import ValidationError
+from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.db.models.functions import Lower
 from django.urls import reverse
 from django.utils.translation import pgettext_lazy, ugettext_lazy as _
 
 from pretix.base.forms import I18nModelForm
-from pretix.base.models import Item, ItemVariation, Quota, Voucher
+from pretix.base.models import Item, Voucher
 from pretix.control.forms import SplitDateTimePickerWidget
-from pretix.control.forms.widgets import Select2
+from pretix.control.forms.widgets import Select2, Select2ItemVarQuota
 from pretix.control.signals import voucher_form_validation
 
 
+class FakeChoiceField(forms.ChoiceField):
+    def valid_value(self, value):
+        return True
+
+
 class VoucherForm(I18nModelForm):
-    itemvar = forms.ChoiceField(
+    itemvar = FakeChoiceField(
         label=_("Product"),
         help_text=_(
             "This product is added to the user's cart if the voucher is redeemed."
@@ -72,43 +77,48 @@ class VoucherForm(I18nModelForm):
             del self.fields['subevent']
 
         choices = []
-        for i in self.instance.event.items.prefetch_related('variations').all():
-            variations = list(i.variations.all())
-            if variations:
-                choices.append((str(i.pk), _('{product} – Any variation').format(product=i.name)))
-                for v in variations:
-                    choices.append(('%d-%d' % (i.pk, v.pk), '%s – %s' % (i.name, v.value)))
-            else:
-                choices.append((str(i.pk), i.name))
-        for q in self.instance.event.quotas.all():
-            choices.append(('q-%d' % q.pk, _('Any product in quota "{quota}"').format(quota=q)))
         self.fields['itemvar'].choices = choices
+        self.fields['itemvar'].widget = Select2ItemVarQuota(
+            attrs={
+                'data-model-select2': 'generic',
+                'data-select2-url': reverse('control:event.vouchers.itemselect2', kwargs={
+                    'event': instance.event.slug,
+                    'organizer': instance.event.organizer.slug,
+                }),
+                'data-placeholder': ''
+            }
+        )
+        self.fields['itemvar'].widget.choices = self.fields['itemvar'].choices
+        self.fields['itemvar'].required = True
 
     def clean(self):
         data = super().clean()
 
         if not self._errors:
-            itemid = quotaid = None
-            iv = self.data.get('itemvar', '')
-            if iv.startswith('q-'):
-                quotaid = iv[2:]
-            elif '-' in iv:
-                itemid, varid = iv.split('-')
-            else:
-                itemid, varid = iv, None
-
-            if itemid:
-                self.instance.item = Item.objects.get(pk=itemid, event=self.instance.event)
-                if varid:
-                    self.instance.variation = ItemVariation.objects.get(pk=varid, item=self.instance.item)
+            try:
+                itemid = quotaid = None
+                iv = self.data.get('itemvar', '')
+                if iv.startswith('q-'):
+                    quotaid = iv[2:]
+                elif '-' in iv:
+                    itemid, varid = iv.split('-')
                 else:
-                    self.instance.variation = None
-                self.instance.quota = None
+                    itemid, varid = iv, None
 
-            else:
-                self.instance.quota = Quota.objects.get(pk=quotaid, event=self.instance.event)
-                self.instance.item = None
-                self.instance.variation = None
+                if itemid:
+                    self.instance.item = self.instance.event.items.get(pk=itemid)
+                    if varid:
+                        self.instance.variation = self.instance.item.variations.get(pk=varid)
+                    else:
+                        self.instance.variation = None
+                    self.instance.quota = None
+
+                else:
+                    self.instance.quota = self.instance.event.quotas.get(pk=quotaid)
+                    self.instance.item = None
+                    self.instance.variation = None
+            except ObjectDoesNotExist:
+                raise ValidationError(_("Invalid product selected."))
 
         if 'codes' in data:
             data['codes'] = [a.strip() for a in data.get('codes', '').strip().split("\n") if a]

src/pretix/control/forms/widgets.py

@@ -36,3 +36,23 @@ class Select2(Select2Mixin, forms.Select):
 
 class Select2Multiple(Select2Mixin, forms.SelectMultiple):
     pass
+
+
+class Select2ItemVarQuotaMixin(Select2Mixin):
+
+    def options(self, name, value, attrs=None):
+        if value and value[0]:
+            yield self.create_option(
+                None,
+                value[0],
+                value[0],
+                True,
+                0,
+                subindex=None,
+                attrs=attrs
+            )
+        return
+
+
+class Select2ItemVarQuota(Select2ItemVarQuotaMixin, forms.Select):
+    pass

src/pretix/control/urls.py

@@ -142,6 +142,7 @@ urlpatterns = [
         url(r'^vouchers/$', vouchers.VoucherList.as_view(), name='event.vouchers'),
         url(r'^vouchers/tags/$', vouchers.VoucherTags.as_view(), name='event.vouchers.tags'),
         url(r'^vouchers/rng$', vouchers.VoucherRNG.as_view(), name='event.vouchers.rng'),
+        url(r'^vouchers/item_select$', typeahead.itemvarquota_select2, name='event.vouchers.itemselect2'),
         url(r'^vouchers/(?P<voucher>\d+)/$', vouchers.VoucherUpdate.as_view(), name='event.voucher'),
         url(r'^vouchers/(?P<voucher>\d+)/delete$', vouchers.VoucherDelete.as_view(),
             name='event.voucher.delete'),

src/pretix/control/views/typeahead.py

@@ -158,6 +158,85 @@ def checkinlist_select2(request, **kwargs):
     return JsonResponse(doc)
 
 
+@event_permission_required(None)
+def itemvarquota_select2(request, **kwargs):
+    query = request.GET.get('query', '')
+    try:
+        page = int(request.GET.get('page', '1'))
+    except ValueError:
+        page = 1
+
+    choices = []
+
+    if not request.event.has_subevents:
+        # We are very unlikely to need pagination
+        itemqs = request.event.items.prefetch_related('variations').filter(name__icontains=i18ncomp(query))
+        quotaqs = request.event.quotas.filter(name__icontains=query)
+        more = False
+    else:
+        # We can't do proper pagination on a UNION-like query, so we hack it.
+        if query:
+            # Don't paginate
+            quotaf = Q(name__icontains=query)
+            try:
+                dt = parse(query)
+            except ValueError:
+                pass
+            else:
+                tz = request.event.timezone
+                if dt and request.event.has_subevents:
+                    dt_start = make_aware(datetime.combine(dt.date(), time(hour=0, minute=0, second=0)), tz)
+                    dt_end = make_aware(datetime.combine(dt.date(), time(hour=23, minute=59, second=59)), tz)
+                    quotaf |= Q(subevent__date_from__gte=dt_start) & Q(subevent__date_from__lte=dt_end)
+
+            itemqs = request.event.items.prefetch_related('variations').filter(name__icontains=i18ncomp(query))
+            quotaqs = request.event.quotas.filter(quotaf).select_related('subevent')
+            more = False
+        else:
+            if page == 1:
+                itemqs = request.event.items.prefetch_related('variations').filter(name__icontains=i18ncomp(query))
+            else:
+                itemqs = request.event.items.none()
+            quotaqs = request.event.quotas.filter(name__icontains=query).select_related('subevent')
+            total = quotaqs.count()
+            pagesize = 20
+            offset = (page - 1) * pagesize
+            quotaqs = quotaqs[offset:offset + pagesize]
+            more = total >= (offset + pagesize)
+
+    for i in itemqs:
+        variations = list(i.variations.all())
+        if variations:
+            choices.append((str(i.pk), _('{product} – Any variation').format(product=i.name), ''))
+            for v in variations:
+                choices.append(('%d-%d' % (i.pk, v.pk), '%s – %s' % (i.name, v.value), ''))
+        else:
+            choices.append((str(i.pk), i.name, ''))
+    for q in quotaqs:
+        if request.event.has_subevents:
+            choices.append(('q-%d' % q.pk,
+                            _('Any product in quota "{quota}"').format(
+                                quota=q
+                            ), str(q.subevent)))
+        else:
+            choices.append(('q-%d' % q.pk, _('Any product in quota "{quota}"').format(quota=q), ''))
+
+    doc = {
+        'results': [
+            {
+                'id': k,
+                'text': str(v),
+                'event': str(t),
+            }
+            for k, v, t in choices
+        ],
+        'pagination': {
+            "more": more
+        }
+    }
+    return JsonResponse(doc)
+
+
 def organizer_select2(request):
     term = request.GET.get('query', '')
     try:

src/pretix/static/pretixcontrol/js/ui/main.js

@@ -281,7 +281,23 @@ var form_handlers = function (el) {
                         page: params.page || 1
                     }
                 }
-            }
+            },
+            templateResult: function (res) {
+                if (!res.id) {
+                    return res.text;
+                }
+                var $ret = $("<span>").append(
+                    $("<span>").addClass("primary").append($("<div>").text(res.text).html())
+                );
+                if (res.event) {
+                    $ret.append(
+                        $("<span>").addClass("secondary").append(
+                            $("<span>").addClass("fa fa-calendar fa-fw")
+                        ).append(" ").append($("<div>").text(res.event).html())
+                    );
+                }
+                return $ret;
+            },
         }).on("select2:select", function () {
             // Allow continuing to select
             if ($s.hasAttribute("multiple")) {

src/pretix/static/pretixcontrol/scss/main.scss

@@ -322,16 +322,17 @@ body.loading #wrapper {
     width: 300px;
 }
 .event-dropdown, .mobile-event-dropdown, .select2-results {
-    .event-name-full {
+    .event-name-full, .primary {
         display: block;
     }
-    .event-daterange, .event-organizer {
+    .event-daterange, .event-organizer, .secondary {
         display: block;
         font-size: $font-size-small;
         color: $text-muted;
     }
     .active .event-daterange, .active .event-organizer, .active a,
     .select2-results__option--highlighted .event-daterange,
+    .select2-results__option--highlighted .secondary,
     .select2-results__option--highlighted .event-organizer {
         color: white;
     }