+import re
+
+from forum.models.user import User
+
+def auto_user_link(node, content):
+ patern = r'@\w+'
+ appeals = re.findall(patern, content)
+
+ for appeal in appeals:
+ # Try to find the profile URL
+ username = appeal[1:]
+ profile_url = None
+
+ try:
+ user = User.objects.get(username__iexact=username)
+ profile_url = user.get_absolute_url()
+ except User.DoesNotExist:
+ """If we don't find the user from the first time, the interesting part
+ begins. We look through all the authors (looking through question,
+ comments, answers, and if it matches some of the -- we link him."""
+
+ # We should find the root of the node tree (question) the current node belongs to.
+ if node.node_type == "question":
+ question = node
+ elif node.node_type == "answer":
+ question = node.question
+ elif node.node_type == "comment":
+ if not node.question:
+ question = node
+ else:
+ question = node.question
+
+ # Now we've got the root question. Let's get the list of active users.
+ active_users = question.get_active_users()
+
+ for active_user in active_users:
+ if active_user.username.lower().startswith(username.lower()):
+ profile_url = active_user.get_absolute_url()
+
+ if (profile_url is not None) and (appeal is not None):
+ auto_link = '<a href="%s">%s</a>' % (profile_url, appeal)
+ content = content.replace(appeal, auto_link)
+
+ return content
\ No newline at end of file