Function useGraphInstance

ui/src/components/graph/useGraphInstance.ts:60–351

({
  allNodes,
  allLinks,
  communityData,
  layoutConfig,
}: UseGraphInstanceOptions)

}

export function useGraphInstance({
  allNodes,
  allLinks,
  communityData,
  layoutConfig,
}: UseGraphInstanceOptions): UseGraphInstanceResult {
  // Stable graph instance — created once, never replaced.
  const graph = useMemo(() => new Graph({ multi: true, type: 'directed' }), []);

  // Worker ref — persists across renders, terminated on unmount
  const workerRef = useRef<Worker | null>(null);

  // Guard against unmount — worker.onmessage may fire after cleanup
  const unmountedRef = useRef(false);

  // Track which dataset the worker is computing for (to discard stale results)
  const requestIdRef = useRef(0);

  const [layoutReady, setLayoutReady] = useState(false);

  // Derived from config
  const flatMode = layoutConfig.flatMode ?? false;
  const structuralTypes = useMemo(
    () =>
      flatMode ? new Set<string>() : new Set(layoutConfig.structuralTypes),
    [layoutConfig.structuralTypes, flatMode],
  );

  // Single effect: rebuild graph and run d3-force worker when data changes.
  useEffect(() => {
    graph.clear();
    setLayoutReady(false);

    if (allNodes.length === 0) return;

    const { assignments, colorMap, names } = communityData;
    const { getNodeColor, getLinkColor, getCommunityColor } = layoutConfig;

    // ── Pre-compute degree (connection count) per node ─────────────────
    const degreeMap = new Map<string, number>();
    for (const link of allLinks) {
      const s = endpointId(link.source);
      const t = endpointId(link.target);
      degreeMap.set(s, (degreeMap.get(s) || 0) + 1);
      degreeMap.set(t, (degreeMap.get(t) || 0) + 1);
    }

    // ── Build ALL nodes with initial x:0, y:0 ──────────────────────────
    const nodeIdSet = new Set<string>();
    const serializedNodes = allNodes.map((node) => {
      nodeIdSet.add(node.id);
      const typeColor = getNodeColor(node.type);
      const commColor = getCommunityColor(assignments, colorMap, node.id);
      const cid = assignments[node.id];
      const commName = cid !== undefined ? names.get(cid) : undefined;
      const degree = degreeMap.get(node.id) || 0;
      const size = nodeSize(degree, node.type, structuralTypes);
      return {