packages/cli/src/utils/readStdin.ts

/**
 * @license
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

export async function readStdin(): Promise<string> {
  return new Promise((resolve, reject) => {
    let data = '';
    process.stdin.setEncoding('utf8');

    const onReadable = () => {
      let chunk;
      while ((chunk = process.stdin.read()) !== null) {
        data += chunk;
      }
    };

    const onEnd = () => {
      cleanup();
      resolve(data);
    };

    const onError = (err: Error) => {
      cleanup();
      reject(err);
    };

    const cleanup = () => {
      process.stdin.removeListener('readable', onReadable);
      process.stdin.removeListener('end', onEnd);
      process.stdin.removeListener('error', onError);
    };

    process.stdin.on('readable', onReadable);
    process.stdin.on('end', onEnd);
    process.stdin.on('error', onError);
  });
}