Function waitForViewerState

examples/pdf-server/server.ts:319–338

* Wait for the viewer to report its current state (page, zoom, selection, …) * as a JSON string. Same timeout/abort semantics as waitForSaveData.

(
  requestId: string,
  signal?: AbortSignal,
)

 * as a JSON string. Same timeout/abort semantics as waitForSaveData.
 */
function waitForViewerState(
  requestId: string,
  signal?: AbortSignal,
): Promise<string> {
  return new Promise<string>((resolve, reject) => {
    const settle = (v: string | Error) => {
      clearTimeout(timer);
      signal?.removeEventListener("abort", onAbort);
      pendingStateRequests.delete(requestId);
      v instanceof Error ? reject(v) : resolve(v);
    };
    const onAbort = () => settle(new Error("interact request cancelled"));
    const timer = setTimeout(
      () => settle(new Error("Timeout waiting for viewer state")),
      GET_PAGES_TIMEOUT_MS,
    );
    signal?.addEventListener("abort", onAbort);
    pendingStateRequests.set(requestId, settle);
  });
}

interface QueueEntry {
  commands: PdfCommand[];