import type { Awaitable } from "./Awaitable";

export function finds<T>(
  predicate: (value: T, index: number) => Awaitable<unknown>,
): TransformStream<T, T> {
  let index = 0;
  let found = false;

  return new TransformStream<T, T>({
    async transform(chunk, controller) {
      if (found) return; // Already found, ignore further chunks

      const shouldEmit = await predicate(chunk, index++);
      if (shouldEmit) {
        found = true;
        controller.enqueue(chunk);
        controller.terminate(); // Stop the stream after finding the first match
      }
    },
  });
}