From 66ed40f8ec0d16aaeaa58e21e083728cf2a73826 Mon Sep 17 00:00:00 2001
From: Paul J Stevens <p.stevens@labdigital.nl>
Date: Wed, 31 May 2017 11:11:19 +0200
Subject: [PATCH] make personalisedpage class abstract

---
 src/wagtail_personalisation/models.py        | 18 +++++++++++++++++-
 src/wagtail_personalisation/views.py         |  5 +++--
 src/wagtail_personalisation/wagtail_hooks.py | 11 +++++++----
 3 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/src/wagtail_personalisation/models.py b/src/wagtail_personalisation/models.py
index 6b6453b..cdf871e 100644
--- a/src/wagtail_personalisation/models.py
+++ b/src/wagtail_personalisation/models.py
@@ -83,11 +83,15 @@ class Segment(ClusterableModel):
         return segment_rules
 
 
-class PersonalisablePage(Page):
+class AbstractPersonalisablePage(models.Model):
     """The personalisable page model. Allows creation of variants with linked
     segments.
 
     """
+
+    class Meta:
+        abstract = True
+
     canonical_page = models.ForeignKey(
         'self', related_name='variations', on_delete=models.SET_NULL,
         blank=True, null=True
@@ -110,6 +114,14 @@ class PersonalisablePage(Page):
     def __str__(self):
         return "{}".format(self.title)
 
+    @classmethod
+    def get_model(cls):
+        try:
+            cls.__subclasses__()[0]
+        except IndexError:
+            raise Exception("Unable to find non-abstract subclass for %s" %
+                            cls.__name)
+
     @cached_property
     def has_variations(self):
         """Return a boolean indicating whether or not the personalisable page
@@ -135,6 +147,10 @@ class PersonalisablePage(Page):
         return not self.canonical_page and self.has_variations
 
 
+class PersonalisablePage(AbstractPersonalisablePage, Page):
+    """ """
+
+
 @cached_classmethod
 def get_edit_handler(cls):
     """Add additional edit handlers to pages that are allowed to have
diff --git a/src/wagtail_personalisation/views.py b/src/wagtail_personalisation/views.py
index ee419e5..3d13602 100644
--- a/src/wagtail_personalisation/views.py
+++ b/src/wagtail_personalisation/views.py
@@ -9,7 +9,7 @@ from wagtail.contrib.modeladmin.options import ModelAdmin, modeladmin_register
 from wagtail.contrib.modeladmin.views import IndexView
 from wagtail.wagtailcore.models import Page
 
-from wagtail_personalisation.models import PersonalisablePage, Segment
+from wagtail_personalisation.models import AbstractPersonalisablePage, Segment
 
 
 class SegmentModelIndexView(IndexView):
@@ -123,9 +123,10 @@ def copy_page_view(request, page_id, segment_id):
     :rtype: django.http.HttpResponseRedirect
 
     """
+    model = AbstractPersonalisablePage.get_model()
     if request.user.has_perm('wagtailadmin.access_admin'):
         segment = get_object_or_404(Segment, pk=segment_id)
-        page = get_object_or_404(PersonalisablePage, pk=page_id)
+        page = get_object_or_404(model, pk=page_id)
 
         slug = "{}-{}".format(page.slug, segment.encoded_name())
         title = "{} ({})".format(page.title, segment.name)
diff --git a/src/wagtail_personalisation/wagtail_hooks.py b/src/wagtail_personalisation/wagtail_hooks.py
index a8f1175..7443a42 100644
--- a/src/wagtail_personalisation/wagtail_hooks.py
+++ b/src/wagtail_personalisation/wagtail_hooks.py
@@ -12,7 +12,7 @@ from wagtail.wagtailcore import hooks
 
 from wagtail_personalisation import admin_urls
 from wagtail_personalisation.adapters import get_segment_adapter
-from wagtail_personalisation.models import PersonalisablePage, Segment
+from wagtail_personalisation.models import AbstractPersonalisablePage, Segment
 from wagtail_personalisation.utils import impersonate_other_page
 
 logger = logging.getLogger(__name__)
@@ -107,9 +107,10 @@ def _check_for_variations(segments, page):
     :rtype: wagtail_personalisation.models.PersonalisablePage or None
 
     """
+    model = AbstractPersonalisablePage.get_model()
     for segment in segments:
         page_class = page.__class__
-        if any(item == PersonalisablePage for item in page_class.__bases__):
+        if any(item == model for item in page_class.__bases__):
 
             variation = page_class.objects.filter(
                 canonical_page=page, segment=segment)
@@ -126,7 +127,8 @@ def page_listing_variant_buttons(page, page_perms, is_parent=False):
     the page (if any) and a 'Create a new variant' button.
 
     """
-    personalisable_page = PersonalisablePage.objects.filter(pk=page.pk)
+    model = AbstractPersonalisablePage.get_model()
+    personalisable_page = model.objects.filter(pk=page.pk)
     segments = Segment.objects.all()
 
     if personalisable_page and len(segments) > 0 and not (
@@ -147,10 +149,11 @@ def page_listing_more_buttons(page, page_perms, is_parent=False):
     create a new variant for the selected segment.
 
     """
+    model = AbstractPersonalisablePage.get_model()
     segments = Segment.objects.all()
     available_segments = [
         item for item in segments
-        if not PersonalisablePage.objects.filter(segment=item, pk=page.pk)
+        if not model.objects.filter(segment=item, pk=page.pk)
     ]
 
     for segment in available_segments: