Function useDeferredLoad

desktop/src/shared/hooks/useDeferredStartup.ts:12–48

(
  options: { immediate?: boolean; timeoutMs?: number } = {},
)

 * (useful when the deferred content is already in view).
 */
export function useDeferredLoad(
  options: { immediate?: boolean; timeoutMs?: number } = {},
): boolean {
  const { immediate = false, timeoutMs = DEFAULT_TIMEOUT_MS } = options;
  const [isReady, setIsReady] = React.useState(immediate);

  React.useEffect(() => {
    if (isReady) {
      return;
    }

    if (immediate) {
      setIsReady(true);
      return;
    }

    const activate = () => {
      setIsReady(true);
    };

    if ("requestIdleCallback" in window) {
      const idleId = window.requestIdleCallback(activate, {
        timeout: timeoutMs,
      });
      return () => {
        window.cancelIdleCallback(idleId);
      };
    }

    const timeoutId = globalThis.setTimeout(activate, timeoutMs);
    return () => {
      globalThis.clearTimeout(timeoutId);
    };
  }, [immediate, isReady, timeoutMs]);

  return isReady;
}

let hasCompletedStartup = false;