fix: preserve checked state when regenerating tripitems

backend/crud.py

@@ -85,20 +85,14 @@ def generate_trip_items(
     selected_tag_ids: List[UUID_t],
     marked_tag_ids: List[UUID_t],
 ) -> Tuple[List[UUID_t], List[UUID_t]]:
-    """Regeneriert TripItems für einen Trip. Löscht alte, legt neue an.
-    Gibt (created_ids, deleted_checked_ids) zurück."""
-    # Sammle bestehende checked Items, falls sie verschwinden
-    deleted_checked: List[UUID_t] = []
-
-    # Lösche alle existierenden TripItems und merke checked, die wegfallen
+    # Map (item_id, tag_id) -> checked
+    previous_checked = {}
     for ti in list(trip.trip_items):
-        if ti.checked:
-            deleted_checked.append(ti.id)
+        previous_checked[(ti.item_id, ti.tag_id)] = ti.checked
         db.delete(ti)
     db.flush()
 
     items = items_for_trip(db, trip.user_id, trip, selected_tag_ids)
-
     created_ids: List[UUID_t] = []
     marked_set = set(marked_tag_ids)
 
@@ -109,11 +103,12 @@ def generate_trip_items(
 
         for tag_id in per_tags:
             calc = render_name(it.name, trip.start_date, trip.end_date)
+            checked = previous_checked.get((it.id, tag_id), False)
             ti = models.TripItem(
                 trip_id=trip.id,
                 item_id=it.id,
                 name_calculated=calc,
-                checked=False,
+                checked=checked,
                 tag_id=tag_id,
             )
             db.add(ti)
@@ -121,4 +116,4 @@ def generate_trip_items(
             created_ids.append(ti.id)
 
     db.flush()
-    return created_ids, deleted_checked
+    return created_ids, []