OpenFrame/lib/async-pool.ts

/**
 * Execute async work with a bounded number of in-flight tasks.
 */
export async function runWithConcurrency<T>(
  items: T[],
  limit: number,
  worker: (item: T) => Promise<void>
): Promise<void> {
  if (items.length === 0) return;

  const concurrency = Math.max(1, Math.floor(limit));
  let nextIndex = 0;

  async function runWorker(): Promise<void> {
    while (true) {
      const currentIndex = nextIndex;
      nextIndex += 1;

      if (currentIndex >= items.length) {
        return;
      }

      await worker(items[currentIndex]);
    }
  }

  const workerCount = Math.min(concurrency, items.length);
  await Promise.all(Array.from({ length: workerCount }, () => runWorker()));
}