update many files

backend/rooms.py

@@ -81,39 +81,54 @@ def search_room(
     return room["name"]
 
 
-def accept_room(
-    user_id,
-    invite_code
-):
+def accept_room(user_id, invite_code):
+
     query = """
     SELECT id
     FROM rooms
     WHERE invite_code = ?
     """
+
     room = fetch_one(
         query,
-        (
-            invite_code,
-        )
+        (invite_code,)
     )
 
     if room is None:
         return None
 
     room_id = room["id"]
-    role = DEFAULT_ROLE
-    query2 = """
-    INSERT INTO "main"."room_members"
-    ("room_id", "user_id", "role")
-    VALUES (?, ?, ?);
+
+    # check dubbele join
+    existing = fetch_one(
+        """
+        SELECT id
+        FROM room_members
+        WHERE room_id = ?
+        AND user_id = ?
+        """,
+        (
+            room_id,
+            user_id
+        )
+    )
+
+    if existing:
+        return None
+
+
+    query = """
+    INSERT INTO room_members
+    (room_id, user_id, role)
+    VALUES (?, ?, ?)
     """
 
     member_id = execute(
-        query2,
+        query,
         (
             room_id,
             user_id,
-            role
+            "member"
         )
     )