+
+ tag_string = request.params.get('tags', '')
+
+ # Add or remove tags
+ bad_tags = []
+ for tag_text in tag_string.split():
+ original_tag_text = tag_text
+ tag_text = tag_text.lower()
+
+ # Adding or removing a tag?
+ if tag_text[0] == '-':
+ add = False
+ tag_text = tag_text[1:]
+ else:
+ # Allow "+foo" to mean "add foo"
+ if tag_text[0] == '+':
+ tag_text = tag_text[1:]
+ add = True
+
+ # Check for special namespaces
+ prefix = None
+ if ':' in tag_text:
+ prefix, tag_text = tag_text.split(':', 1)
+ if prefix not in ['by', 'for', 'of']:
+ # This is bogus. Skip it.
+ bad_tags.append(original_tag_text)
+ continue
+
+ if prefix == 'by':
+ # XXX this needs supporting. silently ignore for now
+ continue
+
+ # Must be 3-50 alphanumeric characters
+ if not re.match('^[a-z0-9]{3,50}$', tag_text):
+ bad_tags.append(original_tag_text)
+ continue
+
+ # Do work!
+ if prefix:
+ target_user = User.get_by(name=tag_text)
+
+ # Special tag; at the moment, just a relationship
+ if prefix == 'by':
+ rel = ArtUserType.BY
+ elif prefix == 'for':
+ rel = ArtUserType.FOR
+ elif prefix == 'of':
+ rel = ArtUserType.OF
+
+ user_assoc_data = dict(art=c.art, user=target_user, type=rel)
+ if add:
+ find_or_create(ArtUser, **user_assoc_data)
+
+ else:
+ # XXX this will die for nonassociations
+ user_assoc = ArtUser.get_by(art=c.art, **user_assoc_data)
+ user_assoc.delete()
+
+ else:
+ # Regular tag
+ if add:
+ tag = find_or_create(TagText, text=tag_text)
+ find_or_create(Tag, art=c.art, tagger=c.user, tagtext=tag)
+
+ else:
+ tag = TagText.get_by(text=tag_text)
+ if tag:
+ # XXX this will die
+ tag_assoc = Tag.get_by(art=c.art, tagger=c.user, tagtext=tag)
+ tag_assoc.delete()
+