import superagent from 'superagent';
import mkdirp from 'mkdirp';
import path from 'path';
import fs from 'fs';

interface DownloadOptions {
  /**
   * 下载地址
   */
  link: string;
  /**
   * 下载本地目录
   * @example
   * /project/path/demo.zip
   */
  dist: string;
}

export interface DownloadResult {
  /**
   * 下载状态, stat为ok代表成功
   */
  stat: string;
  /**
   * 错误码
   */
  code: string;
  /**
   * 提示信息
   */
  message: string;
}

export default async function download(options: DownloadOptions): Promise<DownloadResult> {
  const { dist, link } = options;
  const dirname = path.dirname(options.dist);

  await mkdirp(dirname);

  return new Promise((resolve, reject) => {
    const stream = fs.createWriteStream(dist);
    const req = superagent.get(link).timeout({
      response: 7000, // Wait 5 seconds for the server to start sending,
      deadline: 60000, // but allow 1 minute for the file to finish loading.
    });

    req.on('error', function () {
      reject({
        stat: 'fail',
        code: 'DOWNLOAD_ERROR',
        message: `下载资源失败: ${link}`,
      });
    });

    req.on('end', function () {
      stream.on('close', () => {
        resolve({
          stat: 'ok',
          code: '',
          message: `下载成功: ${dist}`,
        });
      });
    });

    req.pipe(stream);
  });
}