schedule.js

const is = require('@sindresorhus/is');
const later = require('later');
const moment = require('moment-timezone');

module.exports = {
  hasValidTimezone,
  hasValidSchedule,
  isScheduledNow,
};

const scheduleMappings = {
  'every month': 'before 3am on the first day of the month',
  monthly: 'before 3am on the first day of the month',
};

function fixShortHours(input) {
  return input.replace(/( \d?\d)((a|p)m)/g, '$1:00$2');
}

function hasValidTimezone(timezone) {
  if (!moment.tz.zone(timezone)) {
    return [false, `Invalid timezone: ${timezone}`];
  }
  return [true];
}

function hasValidSchedule(schedule) {
  let message;
  if (
    !schedule ||
    schedule === 'at any time' ||
    schedule[0] === 'at any time'
  ) {
    return [true];
  }
  // check if any of the schedules fail to parse
  const hasFailedSchedules = schedule.some(scheduleText => {
    const massagedText = fixShortHours(
      scheduleMappings[scheduleText] || scheduleText
    );
    const parsedSchedule = later.parse.text(massagedText);
    if (parsedSchedule.error !== -1) {
      message = `Failed to parse schedule "${scheduleText}"`;
      // It failed to parse
      return true;
    }
    if (parsedSchedule.schedules.some(s => s.m)) {
      message = `Schedule "${scheduleText}" should not specify minutes`;
      return true;
    }
    if (
      !parsedSchedule.schedules.some(
        s => s.d !== undefined || s.D || s.t_a !== undefined || s.t_b
      )
    ) {
      message = `Schedule "${scheduleText}" has no days of week or time of day`;
      return true;
    }
    // It must be OK
    return false;
  });
  if (hasFailedSchedules) {
    // If any fail then we invalidate the whole thing
    return [false, message];
  }
  return [true];
}

function isScheduledNow(config) {
  let configSchedule = config.schedule;