From 7475e310be759859a9be8bab417b8e38f9a92d83 Mon Sep 17 00:00:00 2001
From: bk-ty <brandon.kiefer@tylertech.com>
Date: Thu, 30 Apr 2026 10:45:08 -0500
Subject: [PATCH] fix: tag tree virtualizer re-measure and scroll-to-selected

Two issues with the tag tree virtualizer after expand/collapse:

1. Expand/collapse changed flatTags length but the virtualizer did not
   remeasure, causing the scroll area to show the wrong total height
   until the next unrelated re-render. Added a useEffect on flatTags
   and virtualizer that calls virtualizer.measure() when the tree
   structure changes.

2. The scroll-to-selected effect read tagIndexMap via the closure's
   stale capture rather than the latest value at fire time, so the
   first render after a tag became selected would scroll to index 0
   instead of the target tag. Added tagIndexMapRef (updated on every
   render) so the effect always reads the current map without needing
   tagIndexMap as a dependency (which would create spurious re-fires).
---
 src/components/tags/TagTree.tsx | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/src/components/tags/TagTree.tsx b/src/components/tags/TagTree.tsx
index 06e299fe..beddde78 100644
--- a/src/components/tags/TagTree.tsx
+++ b/src/components/tags/TagTree.tsx
@@ -78,6 +78,11 @@ export function TagTree({ onOpenTagSettings }: TagTreeProps = {}) {
     return map;
   }, [flatTags]);
 
+  // Always keep a ref to the latest tagIndexMap so the scroll effect can read
+  // current indices without subscribing to map changes. The ref is updated on
+  // every render (outside any effect), so it is always fresh when the effect fires.
+  const tagIndexMapRef = useRef(tagIndexMap);
+  tagIndexMapRef.current = tagIndexMap;
   const virtualizer = useVirtualizer({
     count: flatTags.length,
     getScrollElement: () => scrollContainerRef.current,
@@ -85,17 +90,23 @@ export function TagTree({ onOpenTagSettings }: TagTreeProps = {}) {
     overscan: 20,
   });
 
-  // Scroll to selected tag
+  // Remeasure virtualizer when tree structure changes (expansion/collapse)
+  useEffect(() => {
+    virtualizer.measure();
+  }, [flatTags, virtualizer]);
+
+  // Scroll to selected tag only when the selection changes. We intentionally
+  // read tagIndexMapRef.current (not tagIndexMap directly) so that accordion
+  // expand/collapse — which rebuilds tagIndexMap but does not change
+  // selectedTagId — does NOT trigger a scroll back to the active tag.
   useEffect(() => {
     if (selectedTagId) {
-      const index = tagIndexMap.get(selectedTagId);
+      const index = tagIndexMapRef.current.get(selectedTagId);
       if (index !== undefined) {
-        setTimeout(() => {
-          virtualizer.scrollToIndex(index, { align: 'auto', behavior: 'smooth' });
-        }, 50);
+        virtualizer.scrollToIndex(index, { align: 'center', behavior: 'smooth' });
       }
     }
-  }, [selectedTagId, tagIndexMap, virtualizer]);
+  }, [selectedTagId, virtualizer]);
 
   const [contextMenu, setContextMenu] = useState<{
     position: { x: number; y: number } | null;