moment-biz/lib/utils.js

Handle business days & weekends over multiple years

'use strict';

const moment = require('moment');

const utils = module.exports;

function any(array, cb) {
  var res = false;

  for (let i = 0; !res && i < array.length; ++i)
    res = cb(array[i], i, array);

  return res;
}

// Return the holidays for the provided year (default to current year) and locale (default to global locale)
moment.getHolidays = function(year = moment().year(), locale = moment.locale()) {
  const localeData = moment().locale(locale).localeData();
  const format = localeData._config.holidayFormat || 'DD-MM';
  return (localeData._config.holidays || []).map(date =>
    (date instanceof Function ? date(year) : moment(date, format).year(year)).locale(locale)
  );
};

// Return the holidays of the current year on the current date
moment.fn.getHolidaysOfCurrentYear = function() {
  return moment.getHolidays(this.year(), this.locale());
};

// Returns true if this is a weekend
moment.fn.isWeekend = function() {
  const weekends = this.localeData()._config.weekends || [0, 6];
  return weekends.indexOf(this.day()) >= 0;
};

// Returns true if this is a holiday
moment.fn.isHoliday = function() {
  return any(this.getHolidaysOfCurrentYear(), date => date.dayOfYear() === this.dayOfYear());
};

moment.fn.isFreeDay = function() {
  return this.isWeekend() || this.isHoliday();
};

moment.fn.isBusinessDay = function() {
  return !this.isFreeDay();
};

// Takes a date in format "DD-MM" and returns function that:
//   Takes a year and construct a complete date (DD-MM-YYYY) using the defined date and return prev Friday if it is a
//   Saturday and next Monday if it is a Sunday
utils.adjustIfWELikeInUSA = function(date) {
  date = moment(date, 'DD-MM');
  return year => date.year(year).day() % 6 ? moment(date) : moment(date).add(date.day() === 0 ? 1 : -1, 'day');
};

// Returns a function that takes a year and return you the
//   [xx] (1-N) [day] (0 = sunday - 6 = saturday) of week in [month] (1 = january - 12 = december)
utils.xxDayOfMonth = function(xx, day, month) {
  const date = moment().startOf('day').date(1).month(month - 1);
  return year => {
    const res = moment(date).year(year);
    const old = moment(res);

    res.day(day);
    res.add((xx + (res < old) - 1) * 7, 'day');

    return res;
  };
};

// Returns a function that takes a year and return you the
//   last [day] (0 = sunday - 6 = saturday) of [month] (1 = january - 12 = december)
utils.lastDayOfMonth = function(day, month) {
  const date = moment().startOf('day').month(month - 1);

  return year => {
    const res = moment(date).year(year);

    res.endOf('month').startOf('day').day(day);

    if (res.month() !== month - 1)
      res.subtract(7, 'days');

    return res;
  };
};