Bootstrap the form magic for inline restriction formset variation

controls

doc/development/api/restriction.rst

@@ -213,4 +213,83 @@ In our example, the implementation could look like this::
     If you do not copy down to the ``dict`` objects, you will run into 
     interference problems with other plugins.
 
+Control interface formsets
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+To make it possible for the event organizer to configure your restriction, there is a 
+'Restrictions' page in the item configuration. This page is able to show a formset for
+each restriction plugin, but *you* are required to create this formset. This is why you
+should listen to the the ``tixlcontrol.signals.restriction_formset`` signal.
+
+Currently, the signal comes with only one keyword argument:
+
+    ``item``
+        The instance of ``tixlbase.models.Item`` we want a formset for.
+
+You are expected to return a dict containing the following items:
+
+    ``formsetclass``
+        An inline formset class (not a formset object).
+
+    ``prefix``
+        A unique prefix for your queryset.
+
+    ``title``
+        A title for your formset (normally your plugin name)
+
+
+Our time restriction example looks like this::
+
+    from django.utils.translation import ugettext_lazy as _
+    from django.dispatch import receiver
+    from django.forms.models import inlineformset_factory
+
+    from tixlcontrol.signals import restriction_formset
+    from tixlbase.models import Item
+    from tixlcontrol.views.forms import (
+        VariationsField, RestrictionInlineFormset, RestrictionForm
+    )
+
+    from .models import TimeRestriction
+
+    class TimeRestrictionForm(RestrictionForm):
+
+        class Meta:
+            model = TimeRestriction
+            localized_fields = '__all__'
+            fields = [
+                'variations',
+                'timeframe_from',
+                'timeframe_to',
+                'price',
+            ]
+
+
+    @receiver(restriction_formset)
+    def formset_handler(sender, **kwargs):
+        formset = inlineformset_factory(
+            Item,
+            TimeRestriction,
+            formset=RestrictionInlineFormset,
+            form=TimeRestrictionForm,
+            can_order=False,
+            can_delete=True,
+            extra=0,
+        )
+
+        return {
+            'title': _('Restriction by time'),
+            'formsetclass': formset,
+            'prefix': 'timerestriction',
+        }
+
+
+.. NOTE::
+   If you do use the ``RestrictionInlineFormset``, ``RestrictionForm`` and
+   ``VariationsField`` classes in your implementation, we will do a lot of magic for you
+   to display the ``variations`` field in the form in a nice and consistent way. So please,
+   use these base classes and test carefully, if you make any changes to the behaviour
+   of this field.
+   
+
 .. _caching feature: https://docs.djangoproject.com/en/1.7/topics/cache/

src/tixlcontrol/templates/tixlcontrol/item/restrictions.html

@@ -21,7 +21,7 @@
 					<script type="form-template" data-formset-empty-form>
 						{% escapescript %}
 							<div class="form-horizontal" data-formset-form>
-								{% bootstrap_form set.formset.empty_form layout="horizontal" %}
+								{% bootstrap_form set.formset.initialized_empty_form layout="horizontal" %}
 							</div>
 						{% endescapescript %}
 					</script>

src/tixlcontrol/views/forms.py

@@ -30,3 +30,48 @@ class TolerantFormsetModelForm(forms.ModelForm):
             if field._has_changed(initial_value, data_value):
                 return True
         return False
+
+
+class RestrictionForm(forms.ModelForm):
+
+    def __init__(self, *args, **kwargs):
+        if 'item' in kwargs:
+            self.item = kwargs['item']
+            del kwargs['item']
+            super().__init__(*args, **kwargs)
+            if 'variations' in self.fields:
+                self.fields['variations'] = VariationsField(item=self.item)
+
+
+class RestrictionInlineFormset(forms.BaseInlineFormSet):
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+    def initialized_empty_form(self):
+        form = self.form(
+            auto_id=self.auto_id,
+            prefix=self.add_prefix('__prefix__'),
+            empty_permitted=True,
+            item=self.instance
+        )
+        return form
+
+    def _construct_form(self, i, **kwargs):
+        kwargs['item'] = self.instance
+        return super()._construct_form(i, **kwargs)
+
+
+class VariationsField(forms.ModelMultipleChoiceField):
+
+    def __init__(self, item=None, **kwargs):
+        self.item = item
+        super().__init__(self, **kwargs)
+
+    def _get_choices(self):
+        if not hasattr(self, 'item'):
+            return ()
+        print(self.item.pk)
+        return ()
+
+    choices = property(_get_choices, forms.ChoiceField._set_choices)

src/tixlcontrol/views/item.py

@@ -649,7 +649,7 @@ class ItemRestrictions(ItemDetailMixin, EventPermissionRequiredMixin, TemplateVi
         for receiver, response in responses:
             response['formset'] = response['formsetclass'](
                 self.request.POST if self.request.method == 'POST' else None,
-                queryset=response['queryset'],
+                instance=self.object,
                 prefix=response['prefix'],
             )
             formsets.append(response)

src/tixlplugins/timerestriction/signals.py

@@ -1,10 +1,11 @@
 from django.dispatch import receiver
 from django.utils.timezone import now
 from django.utils.translation import ugettext_lazy as _
-from django import forms
-from django.forms.models import modelformset_factory
+from django.forms.models import inlineformset_factory
 
 from tixlbase.signals import determine_availability
+from tixlbase.models import Item
+from tixlcontrol.views.forms import VariationsField, RestrictionInlineFormset, RestrictionForm
 from tixlcontrol.signals import restriction_formset
 
 from .models import TimeRestriction
@@ -111,11 +112,13 @@ def availability_handler(sender, **kwargs):
     return variations
 
 
-class TimeRestrictionForm(forms.ModelForm):
+class TimeRestrictionForm(RestrictionForm):
+
     class Meta:
         model = TimeRestriction
         localized_fields = '__all__'
         fields = [
+            'variations',
             'timeframe_from',
             'timeframe_to',
             'price',
@@ -124,21 +127,18 @@ class TimeRestrictionForm(forms.ModelForm):
 
 @receiver(restriction_formset)
 def formset_handler(sender, **kwargs):
-    # Handle the signal's input arguments
-    item = kwargs['item']
-
-    formset = modelformset_factory(
+    formset = inlineformset_factory(
+        Item,
         TimeRestriction,
+        formset=RestrictionInlineFormset,
         form=TimeRestrictionForm,
         can_order=False,
         can_delete=True,
         extra=0,
     )
-    queryset = TimeRestriction.objects.filter(item=item)
 
     return {
         'title': _('Restriction by time'),
         'formsetclass': formset,
-        'queryset': queryset,
         'prefix': 'timerestriction',
     }