Prevent removing a tag being used

1 files changed, 9 insertions, 0 deletions

diff --git a/src/db/task_tags.py b/src/db/task_tags.py
index 34366e0..93dc627 100644
--- a/src/db/task_tags.py
+++ b/src/db/task_tags.py
@@ -4,6 +4,15 @@ from typing import List
 
 from model.task_tag import TaskTag
 
+def one_is_used(cursor: Cursor, tag_ids: List[int]) -> bool:
+    if len(tag_ids) >= 1:
+        cursor.execute(
+            "SELECT task_id FROM task_tags WHERE tag_id IN (%s) LIMIT 1" % ",".join("?"*len(tag_ids)),
+            tag_ids)
+        return len(cursor.fetchall()) == 1
+    else:
+        return False
+
 def get(cursor: Cursor) -> List[TaskTag]:
     cursor.execute("SELECT task_id, tag_id FROM task_tags")
     return [TaskTag(r[0], r[1]) for r in cursor.fetchall()]