stars and tags instead of shelves, move to social app

[wolnelektury.git] / apps / social / utils.py

diff --git a/apps/social/utils.py b/apps/social/utils.py
new file mode 100755 (executable)
index 0000000..96f0ca0
--- /dev/null
+++ b/apps/social/utils.py
@@ -0,0 +1,35 @@
+from django.db.models import Q
+from catalogue.models import Tag
+from catalogue import utils
+from catalogue.tasks import touch_tag
+
+
+def likes(user, work):
+    return user.is_authenticated() and work.tags.filter(category='set', user=user).exists()
+
+
+def get_set(user, name):
+    """Returns a tag for use by the user. Creates it, if necessary."""
+    try:
+        tag = Tag.objects.get(category='set', user=user, name=name)
+    except Tag.DoesNotExist:
+        tag = Tag.objects.create(category='set', user=user, name=name,
+                slug=utils.get_random_hash(name), sort_key=name.lower())
+    return tag
+
+
+def set_sets(user, work, sets):
+    """Set tags used for given work by a given user."""
+
+    old_sets = list(work.tags.filter(category='set', user=user))
+
+    work.tags = sets + list(
+            work.tags.filter(~Q(category='set') | ~Q(user=user)))
+
+    for shelf in [shelf for shelf in old_sets if shelf not in sets]:
+        touch_tag(shelf)
+    for shelf in [shelf for shelf in sets if shelf not in old_sets]:
+        touch_tag(shelf)
+
+    # delete empty tags
+    Tag.objects.filter(category='set', user=user, book_count=0).delete()