Rename comments files to chat_comments and add mention parser utility

surfsense_backend/app/utils/chat_comments.py

@@ -0,0 +1,62 @@
+"""
+Utility functions for chat comments, including mention parsing.
+"""
+
+import re
+from uuid import UUID
+
+# Pattern to match @[uuid] mentions in comment content
+MENTION_PATTERN = re.compile(r"@\[([0-9a-fA-F-]{36})\]")
+
+
+def parse_mentions(content: str) -> list[UUID]:
+    """
+    Extract user UUIDs from @[uuid] mentions in content.
+
+    Args:
+        content: Comment text that may contain @[uuid] mentions
+
+    Returns:
+        List of unique user UUIDs found in the content
+    """
+    matches = MENTION_PATTERN.findall(content)
+    unique_uuids = []
+    seen = set()
+
+    for match in matches:
+        try:
+            uuid = UUID(match)
+            if uuid not in seen:
+                seen.add(uuid)
+                unique_uuids.append(uuid)
+        except ValueError:
+            # Invalid UUID format, skip
+            continue
+
+    return unique_uuids
+
+
+def render_mentions(content: str, user_names: dict[UUID, str]) -> str:
+    """
+    Replace @[uuid] mentions with @DisplayName in content.
+
+    Args:
+        content: Comment text with @[uuid] mentions
+        user_names: Dict mapping user UUIDs to display names
+
+    Returns:
+        Content with mentions rendered as @DisplayName
+    """
+
+    def replace_mention(match: re.Match) -> str:
+        try:
+            uuid = UUID(match.group(1))
+            name = user_names.get(uuid)
+            if name:
+                return f"@{name}"
+            # Keep original format if user not found
+            return match.group(0)
+        except ValueError:
+            return match.group(0)
+
+    return MENTION_PATTERN.sub(replace_mention, content)