// Keep a few transfers in flight without flooding mobile connections or allocating
// a promise/network request for every selected file at once.
export const UPLOAD_CONCURRENCY = 3;

export async function runUploadQueue<T>(
  items: readonly T[],
  upload: (item: T, index: number) => Promise<void>,
) {
  let next = 0;
  const errors: unknown[] = [];
  await Promise.all(Array.from({ length: Math.min(UPLOAD_CONCURRENCY, items.length) }, async () => {
    while (next < items.length) {
      const index = next++;
      try {
        await upload(items[index]!, index);
      } catch (error) {
        errors.push(error);
      }
    }
  }));
  // Never release the batch's busy guard while other transfers are still running.
  if (errors.length) throw new AggregateError(errors, "Some uploads failed");
}