import * as fs from 'fs';
import * as http from 'http';
import saveResponse from './funcs/saveResponse';

/** Downloads the given URL and saves it to disk. Throws error if download fails. */
export default function downloadUrlContents({ host, path }: {host: string, path: string}): Promise<fs.ReadStream> {
  return new Promise((resolve, reject) => {
    //Create HTTP request
    const request = http.request({
      family: 4,
      host,
      path,
    }, saveResponse.bind(null, resolve, (reason: string) => { request.abort(); reject(reason); }));

    //In case of connection errors, exit early
    request.on('error', (error) => {
      request.abort();
      reject(error);
    });

    request.end();
  });
}