From 9cbfc7199b1a4a8d909dde8b18e2f2040358cefc Mon Sep 17 00:00:00 2001
From: Diederik van der Boor <vdboor@edoburu.nl>
Date: Tue, 10 Jan 2017 17:18:04 +0100
Subject: [PATCH] Add polymorphic_formset_tags library

---
 polymorphic/templatetags/__init__.py          | 63 ++++++++++++++-
 .../templatetags/polymorphic_formset_tags.py  | 79 +++++++++++++++++++
 2 files changed, 141 insertions(+), 1 deletion(-)
 create mode 100644 polymorphic/templatetags/polymorphic_formset_tags.py

diff --git a/polymorphic/templatetags/__init__.py b/polymorphic/templatetags/__init__.py
index f08e9fb..1c7e071 100644
--- a/polymorphic/templatetags/__init__.py
+++ b/polymorphic/templatetags/__init__.py
@@ -1,5 +1,65 @@
 """
-Template tags to use in the admin.
+Template tags for polymorphic
+
+
+The ``polymorphic_formset_tags`` Library
+----------------------------------------
+
+.. versionadded:: 1.1
+
+To render formsets in the frontend, the ``polymorphic_tags`` provides extra
+filters to implement HTML rendering of polymorphic formsets.
+
+The following filters are provided;
+
+* ``{{ formset|as_script_options }}`` render the ``data-options`` for a JavaScript formset library.
+* ``{{ formset|include_empty_form }}`` provide the placeholder form for an add button.
+* ``{{ form|as_form_type }}`` return the model name that the form instance uses.
+* ``{{ model|as_model_name }}`` performs the same, for a model class or instance.
+
+.. code-block:: html+django
+
+    {% load i18n polymorphic_formset_tags %}
+
+    <div class="inline-group" id="{{ formset.prefix }}-group" data-options="{{ formset|as_script_options }}">
+        {% block add_button %}
+            {% if formset.show_add_button|default_if_none:'1' %}
+                {% if formset.empty_forms %}
+                    {# django-polymorphic formset (e.g. PolymorphicInlineFormSetView) #}
+                    <div class="btn-group" role="group">
+                      {% for model in formset.child_forms %}
+                          <a type="button" data-type="{{ model|as_model_name }}" class="js-add-form btn btn-default">{% glyphicon 'plus' %} {{ model|as_verbose_name }}</a>
+                      {% endfor %}
+                    </div>
+                {% else %}
+                    <a class="btn btn-default js-add-form">{% trans "Add" %}</a>
+                {% endif %}
+            {% endif %}
+        {% endblock %}
+
+        {{ formset.management_form }}
+
+        {% for form in formset|include_empty_form %}
+          {% block formset_form_wrapper %}
+            <div id="{{ form.prefix }}" data-inline-type="{{ form|as_form_type|lower }}" class="inline-related{% if '__prefix__' in form.prefix %} empty-form{% endif %}">
+                {{ form.non_field_errors }}
+
+                {# Add the 'pk' field that is not mentioned in crispy #}
+                {% for field in form.hidden_fields %}
+                  {{ field }}
+                {% endfor %}
+
+                {% block formset_form %}
+                    {% crispy form %}
+                {% endblock %}
+            </div>
+          {% endblock %}
+        {% endfor %}
+    </div>
+
+
+The ``polymorphic_admin_tags`` Library
+--------------------------------------
 
 The ``{% breadcrumb_scope ... %}`` tag makes sure the ``{{ opts }}`` and ``{{ app_label }}``
 values are temporary based on the provided ``{{ base_opts }}``.
@@ -13,4 +73,5 @@ This allows fixing the breadcrumb in admin templates:
     {% block breadcrumbs %}
       {% breadcrumb_scope base_opts %}{{ block.super }}{% endbreadcrumb_scope %}
     {% endblock %}
+
 """
diff --git a/polymorphic/templatetags/polymorphic_formset_tags.py b/polymorphic/templatetags/polymorphic_formset_tags.py
new file mode 100644
index 0000000..575299c
--- /dev/null
+++ b/polymorphic/templatetags/polymorphic_formset_tags.py
@@ -0,0 +1,79 @@
+import json
+
+from django.template import Library
+from django.utils.encoding import force_text
+from django.utils.text import capfirst
+from django.utils.translation import ugettext
+
+from polymorphic.formsets import BasePolymorphicModelFormSet
+
+
+register = Library()
+
+
+@register.filter()
+def include_empty_form(formset):
+    """
+    Make sure the "empty form" is included when displaying a formset (typically table with input rows)
+    """
+    for form in formset:
+        yield form
+
+    if hasattr(formset, 'empty_forms'):
+        # BasePolymorphicModelFormSet
+        for form in formset.empty_forms:
+            yield form
+    else:
+        # Standard Django formset
+        yield formset.empty_form
+
+
+@register.filter
+def as_script_options(formset):
+    """
+    A JavaScript data structure for the JavaScript code
+
+    This generates the ``data-options`` attribute for ``jquery.django-inlines.js``
+    The formset may define the following extra attributes:
+
+    - ``verbose_name``
+    - ``add_text``
+    - ``show_add_button``
+    """
+    verbose_name = getattr(formset, 'verbose_name', formset.model._meta.verbose_name)
+    options = {
+        'prefix': formset.prefix,
+        'pkFieldName': formset.model._meta.pk.name,
+        'addText': getattr(formset, 'add_text', None) or ugettext('Add another %(verbose_name)s') % {
+            'verbose_name': capfirst(verbose_name),
+        },
+        'showAddButton': getattr(formset, 'show_add_button', True),
+        'deleteText': ugettext('Verwijder'),
+    }
+
+    if isinstance(formset, BasePolymorphicModelFormSet):
+        # Allow to add different types
+        options['childTypes'] = [
+            {
+                'name': force_text(model._meta.verbose_name),
+                'type': model._meta.model_name,
+            } for model in formset.child_forms.keys()
+        ]
+
+    return json.dumps(options)
+
+
+@register.filter
+def as_form_type(form):
+    """
+    Usage: ``{{ form|as_form_type }}``
+    """
+    return form._meta.model._meta.model_name
+
+
+@register.filter
+def as_model_name(model):
+    """
+    Usage: ``{{ model|as_model_name }}``
+    """
+    return model._meta.model_name