Research-Stack/5-Applications/text-to-cad/viewer/lib/async/concurrency.js

export async function mapWithConcurrency(items, concurrency, mapper) {
  const list = Array.isArray(items) ? items : [];
  const workerCount = Math.min(
    list.length,
    Math.max(1, Math.floor(Number(concurrency) || 1))
  );
  const results = new Array(list.length);
  let nextIndex = 0;

  async function runWorker() {
    while (nextIndex < list.length) {
      const currentIndex = nextIndex;
      nextIndex += 1;
      results[currentIndex] = await mapper(list[currentIndex], currentIndex);
    }
  }

  await Promise.all(Array.from({ length: workerCount }, () => runWorker()));
  return results;
}