allow only one program or diffusion for pages;

in cms.signals, manage cases when Diffusion.initial is set/changed &
clean up;

fix bug in loglist nav when max_age is 0 (no limit);

work on design for date lists;

fix bug in player on item removal;

aircox_cms/signals.py

@@ -1,3 +1,4 @@
+from django.db.models import Q
 from django.db.models.signals import post_save, pre_delete
 from django.dispatch import receiver
 from django.utils.translation import ugettext as _, ugettext_lazy
@@ -142,17 +143,49 @@ def program_post_saved(sender, instance, created, *args, **kwargs):
     parent.add_child(instance = page)
 
 
+def void_pages_of(page_set):
+    """
+    Return a queryset from page_set that select only empty pages. If
+    `inverse` is True, select only pages that are not empty.
+
+    Empty is defined on theses parameters:
+        - `numchild = 0` => no children
+        - no headline
+        - no body
+    """
+    if not page_set.count():
+        return
+
+    page_set = page_set.filter(numchild = 0)
+
+    # as publications
+    page_set = models.Publication.objects.filter(
+        page_ptr_id__in = page_set.values('pk')
+    )
+
+    # only empty
+    q = (Q(headline__isnull = True) | Q(headline = '')) & \
+        (Q(body__isnull = True) | Q(body = ''))
+    return page_set.filter(q)
+
+
 @receiver(pre_delete, sender=aircox.Program)
 def program_post_deleted(sender, instance, *args, **kwargs):
-    for page in instance.page.all():
-        if page.specific.body or Page.objects.descendant_of(page).count():
-            continue
-        page.delete()
+    void_pages_of(instance.page).delete()
 
 
 @receiver(post_save, sender=aircox.Diffusion)
 def diffusion_post_saved(sender, instance, created, *args, **kwargs):
-    if not created or instance.page.count():
+    initial = instance.initial
+    if initial:
+        if not created and hasattr(instance, 'page'):
+            # fuck it
+            page = instance.page
+            page.diffusion = None
+            page.save()
+        return
+
+    if instance.page:
         return
 
     page = models.DiffusionPage.from_diffusion(
@@ -164,9 +197,5 @@ def diffusion_post_saved(sender, instance, created, *args, **kwargs):
 
 @receiver(pre_delete, sender=aircox.Diffusion)
 def diffusion_pre_deleted(sender, instance, *args, **kwargs):
-    for page in instance.page.all():
-        if page.specific.body or Page.objects.descendant_of(page).count():
-            continue
-        page.delete()
-
+    void_pages_of(instance.page).delete()