From 3447c4d4a43267addb369cc56817a7440731f280 Mon Sep 17 00:00:00 2001
From: Scott Idem <stidem@gmail.com>
Date: Fri, 6 Mar 2026 21:51:31 -0500
Subject: [PATCH] launcher: fix liveQuery reactivity for location-dependent
 queries
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The three liveQueries that depend on $events_slct.event_location_id were
plain liveQuery() calls, not $derived.by(() => liveQuery(...)). This meant
Svelte store changes did NOT cause them to re-run.

Root cause of the 'hung' bug:
- On initial load at /launcher (no location in URL), id = null
- Dexie watches the event_location_id = null index range
- User selects a location (or navigates to /launcher/{id}): store updates
- Sessions for the real location are in a DIFFERENT Dexie range
- Dexie never fires because the null range was never touched
- If sessions are already in IndexedDB cache (no new DB write), the list
  stays permanently frozen at []

Fix: convert lq__event_session_obj_li, lq__location_event_file_obj_li, and
lq__event_location_obj to $derived.by(() => liveQuery(...)). When
event_location_id changes, $derived.by creates a new Observable targeting
the correct location, which immediately queries Dexie for existing cached
data and then watches that range for further changes.

Also: remove the .reverse() before .sortBy('name') on the session query —
.sortBy() always re-sorts so .reverse() before it was a no-op.
---
 .../(launcher)/launcher/+layout.svelte        | 69 +++++++++++--------
 1 file changed, 40 insertions(+), 29 deletions(-)

diff --git a/src/routes/events/[event_id]/(launcher)/launcher/+layout.svelte b/src/routes/events/[event_id]/(launcher)/launcher/+layout.svelte
index e6563b62..d1c6714f 100644
--- a/src/routes/events/[event_id]/(launcher)/launcher/+layout.svelte
+++ b/src/routes/events/[event_id]/(launcher)/launcher/+layout.svelte
@@ -181,20 +181,28 @@
     });
 
     // Event File - For Location
-    let lq__location_event_file_obj_li = liveQuery(async () => {
+    // $derived.by: must recreate the observable when event_location_id changes.
+    // Plain liveQuery() only re-fires when Dexie detects a change in the initially
+    // watched index range — if the id starts as null and changes to a real value,
+    // Dexie never fires because a different range was added (not the null range).
+    let lq__location_event_file_obj_li = $derived.by(() => {
         const id = $events_slct.event_location_id;
-        if (!id) return [];
-        return await db_events.file
-            .where('for_id')
-            .equals(id)
-            .sortBy('filename');
+        return liveQuery(async () => {
+            if (!id) return [];
+            return await db_events.file
+                .where('for_id')
+                .equals(id)
+                .sortBy('filename');
+        });
     });
 
-    // Event Location
-    let lq__event_location_obj = liveQuery(async () => {
+    // Event Location — same reason as above
+    let lq__event_location_obj = $derived.by(() => {
         const id = $events_slct.event_location_id;
-        if (!id) return null;
-        return await db_events.location.get(id);
+        return liveQuery(async () => {
+            if (!id) return null;
+            return await db_events.location.get(id);
+        });
     });
 
     let lq__event_location_obj_li = liveQuery(async () => {
@@ -206,27 +214,30 @@
             .sortBy('name');
     });
 
-    let lq__event_session_obj_li = liveQuery(async () => {
+    // $derived.by: must recreate when event_location_id changes (see comment above).
+    let lq__event_session_obj_li = $derived.by(() => {
         const id = $events_slct.event_location_id;
-        if (!id) return [];
-        if (log_lvl > 1)
-            console.log(
-                `LQ - Using default sort for Event Session list location_id: ${id}`
-            );
-        let results = await db_events.session
-            .where('event_location_id')
-            .equals(id)
-            .reverse()
-            .sortBy('name');
+        return liveQuery(async () => {
+            if (!id) return [];
+            if (log_lvl > 1)
+                console.log(
+                    `LQ - Event Session list location_id: ${id}`
+                );
+            // Note: .reverse() before .sortBy() is a no-op — sortBy always re-sorts.
+            let results = await db_events.session
+                .where('event_location_id')
+                .equals(id)
+                .sortBy('name');
 
-        if (
-            $events_slct.event_session_obj_li &&
-            JSON.stringify($events_slct.event_session_obj_li) !==
-                JSON.stringify(results)
-        ) {
-            $events_slct.event_session_obj_li = [...(results || [])];
-        }
-        return results;
+            if (
+                $events_slct.event_session_obj_li &&
+                JSON.stringify($events_slct.event_session_obj_li) !==
+                    JSON.stringify(results)
+            ) {
+                $events_slct.event_session_obj_li = [...(results || [])];
+            }
+            return results;
+        });
     });
 
     // Event Session (Main View Trigger - Needed for Global Header/Idle)