Polished AttributeForm to better handle changes to an attribute instance. Introduced...
[philo.git] / forms.py
index 0e034df..69273f0 100644 (file)
--- a/forms.py
+++ b/forms.py
@@ -7,7 +7,7 @@ from django.forms.formsets import TOTAL_FORM_COUNT
 from django.template import loader, loader_tags, TemplateDoesNotExist, Context, Template as DjangoTemplate
 from django.utils.datastructures import SortedDict
 from philo.admin.widgets import ModelLookupWidget
-from philo.models import Entity, Template, Contentlet, ContentReference
+from philo.models import Entity, Template, Contentlet, ContentReference, Attribute
 from philo.utils import fattr
 
 
@@ -95,6 +95,61 @@ class EntityForm(EntityFormBase): # Would inherit from ModelForm directly if it
                return instance
 
 
+class AttributeForm(ModelForm):
+       def __init__(self, *args, **kwargs):
+               super(AttributeForm, self).__init__(*args, **kwargs)
+               
+               # This is necessary because model forms store changes to self.instance in their clean method.
+               # Mutter mutter.
+               self._cached_value_ct = self.instance.value_content_type
+               self._cached_value = self.instance.value
+               
+               if self.instance.value is not None:
+                       value_field = self.instance.value.value_formfield()
+                       if value_field:
+                               self.fields['value'] = value_field
+                       if hasattr(self.instance.value, 'content_type'):
+                               self.fields['content_type'] = self.instance.value._meta.get_field('content_type').formfield(initial=getattr(self.instance.value.content_type, 'pk', None))
+       
+       def save(self, *args, **kwargs):
+               # At this point, the cleaned_data has already been stored on self.instance.
+               if self.instance.value_content_type != self._cached_value_ct:
+                       if self.instance.value is not None:
+                               self._cached_value.delete()
+                               if 'value' in self.cleaned_data:
+                                       del(self.cleaned_data['value'])
+                       
+                       if self.instance.value_content_type is not None:
+                               # Make a blank value of the new type! Run special code for content_type attributes.
+                               if hasattr(self.instance.value_content_type.model_class(), 'content_type'):
+                                       if self._cached_value and hasattr(self._cached_value, 'content_type'):
+                                               new_ct = self._cached_value.content_type
+                                       else:
+                                               new_ct = None
+                                       new_value = self.instance.value_content_type.model_class().objects.create(content_type=new_ct)
+                               else:
+                                       new_value = self.instance.value_content_type.model_class().objects.create()
+                               
+                               new_value.apply_data(self.cleaned_data)
+                               new_value.save()
+                               self.instance.value = new_value
+               else:
+                       # The value type is the same, but one of the fields has changed.
+                       # Check to see if the changed value was the content type. We have to check the
+                       # cleaned_data because self.instance.value.content_type was overridden.
+                       if hasattr(self.instance.value, 'content_type') and 'content_type' in self.cleaned_data and 'value' in self.cleaned_data and (not hasattr(self._cached_value, 'content_type') or self._cached_value.content_type != self.cleaned_data['content_type']):
+                               self.cleaned_data['value'] = None
+                       
+                       self.instance.value.apply_data(self.cleaned_data)
+                       self.instance.value.save()
+               
+               super(AttributeForm, self).save(*args, **kwargs)
+               return self.instance
+       
+       class Meta:
+               model = Attribute
+
+
 class ContainerForm(ModelForm):
        def __init__(self, *args, **kwargs):
                super(ContainerForm, self).__init__(*args, **kwargs)