bofh.js

const http = require('http');
const fs = require('fs');
const os = require('os');

const sourceUrl = 'http://pages.cs.wisc.edu/~ballard/bofh/excuses';
const dataFile = `${process.env.APPDATA}\\fun-data`;

function download() {
  return new Promise((resolve, reject) => {
    http.get(sourceUrl, incoming => {
      incoming.on('error', reject);
      incoming.pipe(fs.createWriteStream(dataFile)).on('close', resolve);
    });
  });
}

function dataFileExists() {
  return new Promise(resolve => {
    fs.exists(dataFile, resolve);
  });
}

function readDataFile() {
  return new Promise((resolve, reject) => {
    fs.readFile(dataFile, (error, data) => {
      if (error) {
        reject(error);
      }
      resolve(data.toString());
    });
  });
}

function pickRandom(array) {
  return array[Math.floor(Math.random() * Math.floor(array.length + 1))]
}

(async function () {
  if (!await dataFileExists()) {
    await download();
  }
  const data = await readDataFile();
  const messages = data.split(/\n/g);
  const message = pickRandom(messages);
  console.log(message);
})();