Label editing

backend/app/services/link_service.py

@@ -172,3 +172,65 @@ def list_tags():
             tags.append(row['name'])
             seen.add(row['name'].casefold())
     return tags
+
+
+def list_user_labels(user_id: str):
+    with get_connection() as conn:
+        rows = conn.execute(
+            'SELECT id, name, created_by FROM tags WHERE created_by = ? ORDER BY name',
+            (user_id,),
+        ).fetchall()
+    return [dict(row) for row in rows]
+
+
+def create_label(user_id: str, name: str):
+    normalized = normalize_tags([name])
+    label = normalized[0] if normalized else ''
+    if not label:
+        raise ValueError('Label cannot be empty')
+    with get_connection() as conn:
+        existing = conn.execute(
+            'SELECT id FROM tags WHERE lower(name) = lower(?)', (label,)
+        ).fetchone()
+        if existing:
+            raise ValueError('Label already exists')
+        label_id = str(uuid4())
+        conn.execute(
+            'INSERT INTO tags (id, name, created_by) VALUES (?, ?, ?)',
+            (label_id, label, user_id),
+        )
+        conn.commit()
+    return {'id': label_id, 'name': label, 'created_by': user_id}
+
+
+def update_label(label_id: str, user_id: str, name: str):
+    normalized = normalize_tags([name])
+    if not normalized:
+        raise ValueError('Label cannot be empty')
+    with get_connection() as conn:
+        current = conn.execute(
+            'SELECT id, name, created_by FROM tags WHERE id = ?', (label_id,)
+        ).fetchone()
+        if current is None or current['created_by'] != user_id:
+            return None
+        duplicate = conn.execute(
+            'SELECT id FROM tags WHERE lower(name) = lower(?) AND id != ?',
+            (normalized[0], label_id),
+        ).fetchone()
+        if duplicate:
+            raise ValueError('Label already exists')
+        conn.execute('UPDATE tags SET name = ? WHERE id = ?', (normalized[0], label_id))
+        conn.commit()
+    return {'id': label_id, 'name': normalized[0], 'created_by': user_id}
+
+
+def delete_label(label_id: str, user_id: str | None = None, is_admin: bool = False):
+    with get_connection() as conn:
+        current = conn.execute(
+            'SELECT id, created_by FROM tags WHERE id = ?', (label_id,)
+        ).fetchone()
+        if current is None or (not is_admin and current['created_by'] != user_id):
+            return False
+        conn.execute('DELETE FROM tags WHERE id = ?', (label_id,))
+        conn.commit()
+    return True