export function throwIfAborted(signal?: AbortSignal): void {
  if (!signal?.aborted) {
    return;
  }

  throw signal.reason instanceof Error ? signal.reason : new Error(String(signal.reason ?? 'MCP request aborted'));
}

export async function abortable<T>(promise: Promise<T>, signal?: AbortSignal): Promise<T> {
  if (!signal) {
    return promise;
  }

  throwIfAborted(signal);

  return await new Promise<T>((resolve, reject) => {
    let settled = false;
    const cleanup = () => signal.removeEventListener('abort', onAbort);
    const onAbort = () => {
      if (settled) {
        return;
      }

      settled = true;
      cleanup();
      reject(
        signal.reason instanceof Error ? signal.reason : new Error(String(signal.reason ?? 'MCP request aborted'))
      );
    };

    signal.addEventListener('abort', onAbort, { once: true });
    promise.then(
      (value) => {
        if (settled) {
          return;
        }

        settled = true;
        cleanup();
        resolve(value);
      },
      (error) => {
        if (settled) {
          return;
        }

        settled = true;
        cleanup();
        reject(error);
      }
    );
  });
}