+def choose_cite(request, book_id=None, tag_ids=None):
+ """Choose a cite for main page, for book or for set of tags."""
+ try:
+ assert request.user.is_staff
+ assert 'choose_cite' in request.GET
+ cite = Cite.objects.get(pk=request.GET['choose_cite'])
+ except (AssertionError, Cite.DoesNotExist):
+ if book_id is not None:
+ cites = Cite.objects.filter(Q(book=book_id) | Q(book__ancestor=book_id))
+ elif tag_ids is not None:
+ tags = Tag.objects.filter(pk__in=tag_ids)
+ cites = cites_for_tags(tags)
+ else:
+ cites = Cite.objects.all()
+ stickies = cites.filter(sticky=True)
+ count = stickies.count()
+ if count:
+ cite = stickies[randint(0, count - 1)]
+ else:
+ count = cites.count()
+ if count:
+ cite = cites[randint(0, count - 1)]
+ else:
+ cite = None
+ return cite
+
+
+@ssi_variable(register, name='choose_cite', patch_response=[add_never_cache_headers])
+def choose_cite_tag(request, book_id=None, tag_ids=None):
+ cite = choose_cite(request, book_id, tag_ids)
+ return cite.pk if cite is not None else None
+
+
+@register.inclusion_tag('social/cite_promo.html')
+def render_cite(cite):