shiftly/lib/index.js

Calculate common public safety shift schedules.

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.ShiftConfiguration = undefined;

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _momentTimezone = require('moment-timezone');

var _momentTimezone2 = _interopRequireDefault(_momentTimezone);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function reverse(s) {
  var o = [];
  for (var i = 0, len = s.length; i <= len; i += 1) {
    o.push(s.charAt(len - i));
  }
  return o.join('');
}

var ShiftConfiguration = exports.ShiftConfiguration = function () {
  // eslint-disable-line import/prefer-default-export
  /**
  * Create a ShiftConfiguration.
  * @param {string} pattern - The department's shift pattern.
  * @param {string} timeZone - The department's timezone.
  * @param {string} shiftStart - The start time of the department's shift.
  * @param {string} firstDay - The first day of the pattern (assumed to be in local tz).
  */
  function ShiftConfiguration() {
    var _ref = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {},
        pattern = _ref.pattern,
        _ref$timeZone = _ref.timeZone,
        timeZone = _ref$timeZone === undefined ? 'US/Eastern' : _ref$timeZone,
        _ref$shiftStart = _ref.shiftStart,
        shiftStart = _ref$shiftStart === undefined ? '0800' : _ref$shiftStart,
        _ref$firstDay = _ref.firstDay,
        firstDay = _ref$firstDay === undefined ? '2016-10-30' : _ref$firstDay;

    _classCallCheck(this, ShiftConfiguration);

    this.pattern = pattern;
    this.timeZone = timeZone;
    this.shiftStart = shiftStart;
    this.firstDay = firstDay;
    this.shiftStartDate = _momentTimezone2.default.tz(this.shiftStart, 'hmm', this.timeZone);
    this.patternStart = _momentTimezone2.default.tz(this.firstDay, this.timeZone).startOf('day');
  }

  _createClass(ShiftConfiguration, [{
    key: 'normalize',
    value: function normalize(incomingDate) {
      return (0, _momentTimezone2.default)(incomingDate).tz(this.timeZone);
    }
  }, {
    key: 'reversePattern',
    value: function reversePattern() {
      return '' + this.pattern.charAt(0) + reverse(this.pattern.substring(1, this.pattern.length));
    }
  }, {
    key: 'beforeShiftChange',
    value: function beforeShiftChange(date) {
      return date.hours() < this.shiftStartDate.hours();
    }
  }, {
    key: 'daysFromPatternStart',
    value: function daysFromPatternStart(start) {
      return start.startOf('day').diff(this.patternStart.startOf('day'), 'days');
    }
  }, {
    key: 'calculateShift',
    value: function calculateShift(date) {
      var momentDate = this.normalize(date);
      var checkDate = this.beforeShiftChange(momentDate) ? momentDate.subtract(1, 'days') : momentDate;

      var pattern = this.pattern;
      var daysFromStart = this.daysFromPatternStart(checkDate);

      if (daysFromStart < 0) {
        pattern = this.reversePattern();
      }

      var patternLength = this.pattern.length;

      var mod = Math.abs(daysFromStart) % patternLength;
      var shift = null;

      for (var i = 0, len = patternLength; i < len; i += 1) {
        if (i === mod) {
          shift = pattern[i].toUpperCase();
          break;
        }
      }

      return shift;
    }
  }]);

  return ShiftConfiguration;
}();