Function useThreadRows

src/features/app/hooks/useThreadRows.ts:22–145

(threadParentById: Record<string, string>)

};

export function useThreadRows(threadParentById: Record<string, string>) {
  const cacheRef = useRef(
    new WeakMap<
      ThreadSummary[],
      Map<string, ThreadRowCacheEntry>
    >(),
  );
  const cacheParentRef = useRef(threadParentById);
  if (cacheParentRef.current !== threadParentById) {
    cacheParentRef.current = threadParentById;
    cacheRef.current = new WeakMap<
      ThreadSummary[],
      Map<string, ThreadRowCacheEntry>
    >();
  }

  const getThreadRows = useCallback(
    (
      threads: ThreadSummary[],
      isExpanded: boolean,
      workspaceId: string,
      getPinTimestamp: (workspaceId: string, threadId: string) => number | null,
      pinVersion = 0,
    ): ThreadRowResult => {
      const cacheKey = `${workspaceId}:${isExpanded ? "1" : "0"}`;
      const threadCache = cacheRef.current.get(threads);
      const cachedEntry = threadCache?.get(cacheKey);
      if (cachedEntry && cachedEntry.pinVersion === pinVersion) {
        return cachedEntry.result;
      }

      const visibleThreads = threads.filter((thread) => {
        if (!thread.isSubagent) {
          return true;
        }
        return Boolean(threadParentById[thread.id]);
      });
      const threadIds = new Set(visibleThreads.map((thread) => thread.id));
      const childrenByParent = new Map<string, ThreadSummary[]>();
      const roots: ThreadSummary[] = [];
      const resolveVisibleParentId = (threadId: string) => {
        let current = threadParentById[threadId];
        const visited = new Set<string>([threadId]);
        while (current && !visited.has(current)) {
          if (threadIds.has(current)) {
            return current;
          }
          visited.add(current);
          current = threadParentById[current];
        }
        return null;
      };

      visibleThreads.forEach((thread) => {
        const parentId = resolveVisibleParentId(thread.id);
        if (parentId) {
          const list = childrenByParent.get(parentId) ?? [];
          list.push(thread);