philo/admin/forms/containers.py

   1 from django import forms
   2 from django.contrib.admin.widgets import AdminTextareaWidget
   3 from django.core.exceptions import ObjectDoesNotExist
   4 from django.db.models import Q
   5 from django.forms.models import ModelForm, BaseInlineFormSet, BaseModelFormSet
   6 from django.forms.formsets import TOTAL_FORM_COUNT
   7 from django.utils.datastructures import SortedDict
   8
   9 from philo.admin.widgets import ModelLookupWidget
  10 from philo.models import Contentlet, ContentReference
  11
  12
  13 __all__ = (
  14         'ContentletForm',
  15         'ContentletInlineFormSet',
  16         'ContentReferenceForm',
  17         'ContentReferenceInlineFormSet'
  18 )
  19
  20
  21 class ContainerForm(ModelForm):
  22         def __init__(self, *args, **kwargs):
  23                 super(ContainerForm, self).__init__(*args, **kwargs)
  24                 self.verbose_name = self.instance.name.replace('_', ' ')
  25                 self.prefix = self.instance.name
  26
  27
  28 class ContentletForm(ContainerForm):
  29         content = forms.CharField(required=False, widget=AdminTextareaWidget, label='Content')
  30
  31         def should_delete(self):
  32                 # Delete iff: the data has changed and is now empty.
  33                 return self.has_changed() and not bool(self.cleaned_data['content'])
  34
  35         class Meta:
  36                 model = Contentlet
  37                 fields = ['content']
  38
  39
  40 class ContentReferenceForm(ContainerForm):
  41         def __init__(self, *args, **kwargs):
  42                 super(ContentReferenceForm, self).__init__(*args, **kwargs)
  43                 try:
  44                         self.fields['content_id'].widget = ModelLookupWidget(self.instance.content_type)
  45                 except ObjectDoesNotExist:
  46                         # This will happen when an empty form (which we will never use) gets instantiated.
  47                         pass
  48
  49         def should_delete(self):
  50                 return self.has_changed() and (self.cleaned_data['content_id'] is None)
  51
  52         class Meta:
  53                 model = ContentReference
  54                 fields = ['content_id']
  55
  56
  57 class ContainerInlineFormSet(BaseInlineFormSet):
  58         @property
  59         def containers(self):
  60                 if not hasattr(self, '_containers'):
  61                         self._containers = self.get_containers()
  62                 return self._containers
  63
  64         def total_form_count(self):
  65                 # This ignores the posted management form data... but that doesn't
  66                 # seem to have any ill side effects.
  67                 return len(self.containers.keys())
  68
  69         def _get_initial_forms(self):
  70                 return [form for form in self.forms if form.instance.pk is not None]
  71         initial_forms = property(_get_initial_forms)
  72
  73         def _get_extra_forms(self):
  74                 return [form for form in self.forms if form.instance.pk is None]
  75         extra_forms = property(_get_extra_forms)
  76
  77         def _construct_form(self, i, **kwargs):
  78                 if 'instance' not in kwargs:
  79                         kwargs['instance'] = self.containers.values()[i]
  80
  81                 # Skip over the BaseModelFormSet. We have our own way of doing things!
  82                 form = super(BaseModelFormSet, self)._construct_form(i, **kwargs)
  83
  84                 # Since we skipped over BaseModelFormSet, we need to duplicate what BaseInlineFormSet would do.
  85                 if self.save_as_new:
  86                         # Remove the primary key from the form's data, we are only
  87                         # creating new instances
  88                         form.data[form.add_prefix(self._pk_field.name)] = None
  89
  90                         # Remove the foreign key from the form's data
  91                         form.data[form.add_prefix(self.fk.name)] = None
  92
  93                 # Set the fk value here so that the form can do it's validation.
  94                 setattr(form.instance, self.fk.get_attname(), self.instance.pk)
  95                 return form
  96
  97         def add_fields(self, form, index):
  98                 """Override the pk field's initial value with a real one."""
  99                 super(ContainerInlineFormSet, self).add_fields(form, index)
 100                 if index is not None:
 101                         pk_value = self.containers.values()[index].pk
 102                 else:
 103                         pk_value = None
 104                 form.fields[self._pk_field.name].initial = pk_value
 105
 106         def save_existing_objects(self, commit=True):
 107                 self.changed_objects = []
 108                 self.deleted_objects = []
 109                 if not self.get_queryset():
 110                         return []
 111
 112                 saved_instances = []
 113                 for form in self.initial_forms:
 114                         pk_name = self._pk_field.name
 115                         raw_pk_value = form._raw_value(pk_name)
 116
 117                         # clean() for different types of PK fields can sometimes return
 118                         # the model instance, and sometimes the PK. Handle either.
 119                         pk_value = form.fields[pk_name].clean(raw_pk_value)
 120                         pk_value = getattr(pk_value, 'pk', pk_value)
 121
 122                         # if the pk_value is None, they have just switched to a
 123                         # template which didn't contain data about this container.
 124                         # Skip!
 125                         if pk_value is not None:
 126                                 obj = self._existing_object(pk_value)
 127                                 if form.should_delete():
 128                                         self.deleted_objects.append(obj)
 129                                         obj.delete()
 130                                         continue
 131                                 if form.has_changed():
 132                                         self.changed_objects.append((obj, form.changed_data))
 133                                         saved_instances.append(self.save_existing(form, obj, commit=commit))
 134                                         if not commit:
 135                                                 self.saved_forms.append(form)
 136                 return saved_instances
 137
 138         def save_new_objects(self, commit=True):
 139                 self.new_objects = []
 140                 for form in self.extra_forms:
 141                         if not form.has_changed():
 142                                 continue
 143                         # If someone has marked an add form for deletion, don't save the
 144                         # object.
 145                         if form.should_delete():
 146                                 continue
 147                         self.new_objects.append(self.save_new(form, commit=commit))
 148                         if not commit:
 149                                 self.saved_forms.append(form)
 150                 return self.new_objects
 151
 152
 153 class ContentletInlineFormSet(ContainerInlineFormSet):
 154         def get_containers(self):
 155                 try:
 156                         containers = self.instance.containers[0]
 157                 except ObjectDoesNotExist:
 158                         containers = []
 159
 160                 qs = self.get_queryset().filter(name__in=containers)
 161                 container_dict = SortedDict([(container.name, container) for container in qs])
 162                 for name in containers:
 163                         if name not in container_dict:
 164                                 container_dict[name] = self.model(name=name)
 165
 166                 container_dict.keyOrder = containers
 167                 return container_dict
 168
 169
 170 class ContentReferenceInlineFormSet(ContainerInlineFormSet):
 171         def get_containers(self):
 172                 try:
 173                         containers = self.instance.containers[1]
 174                 except ObjectDoesNotExist:
 175                         containers = {}
 176
 177                 filter = Q()
 178                 for name, ct in containers.items():
 179                         filter |= Q(name=name, content_type=ct)
 180                 qs = self.get_queryset().filter(filter)
 181
 182                 container_dict = SortedDict([(container.name, container) for container in qs])
 183
 184                 keyOrder = []
 185                 for name, ct in containers.items():
 186                         keyOrder.append(name)
 187                         if name not in container_dict:
 188                                 container_dict[name] = self.model(name=name, content_type=ct)
 189
 190                 container_dict.keyOrder = keyOrder
 191                 return container_dict