text: // Core javascript helper functions
  'use strict';
  
  // quickElement(tagType, parentReference [, textInChildNode, attribute, attributeValue ...]);
  function quickElement() {
      const obj = document.createElement(arguments[0]);
      if (arguments[2]) {
          const textNode = document.createTextNode(arguments[2]);
          obj.appendChild(textNode);
      }
      const len = arguments.length;
      for (let i = 3; i < len; i += 2) {
          obj.setAttribute(arguments[i], arguments[i + 1]);
      }
      arguments[1].appendChild(obj);
      return obj;
  }
  
  // "a" is reference to an object
  function removeChildren(a) {
      while (a.hasChildNodes()) {
          a.removeChild(a.lastChild);
      }
  }
  
  // ----------------------------------------------------------------------------
  // Find-position functions by PPK
  // See https://www.quirksmode.org/js/findpos.html
  // ----------------------------------------------------------------------------
  function findPosX(obj) {
      let curleft = 0;
      if (obj.offsetParent) {
          while (obj.offsetParent) {
              curleft += obj.offsetLeft - obj.scrollLeft;
              obj = obj.offsetParent;
          }
      } else if (obj.x) {
          curleft += obj.x;
      }
      return curleft;
  }
  
  function findPosY(obj) {
      let curtop = 0;
      if (obj.offsetParent) {
          while (obj.offsetParent) {
              curtop += obj.offsetTop - obj.scrollTop;
              obj = obj.offsetParent;
          }
      } else if (obj.y) {
          curtop += obj.y;
      }
      return curtop;
  }
  
  //-----------------------------------------------------------------------------
  // Date object extensions
  // ----------------------------------------------------------------------------
  {
      Date.prototype.getTwelveHours = function() {
          return this.getHours() % 12 || 12;
      };
  
      Date.prototype.getTwoDigitMonth = function() {
          return (this.getMonth() < 9) ? '0' + (this.getMonth() + 1) : (this.getMonth() + 1);
      };
  
      Date.prototype.getTwoDigitDate = function() {
          return (this.getDate() < 10) ? '0' + this.getDate() : this.getDate();
      };
  
      Date.prototype.getTwoDigitTwelveHour = function() {
          return (this.getTwelveHours() < 10) ? '0' + this.getTwelveHours() : this.getTwelveHours();
      };
  
      Date.prototype.getTwoDigitHour = function() {
          return (this.getHours() < 10) ? '0' + this.getHours() : this.getHours();
      };
  
      Date.prototype.getTwoDigitMinute = function() {
          return (this.getMinutes() < 10) ? '0' + this.getMinutes() : this.getMinutes();
      };
  
      Date.prototype.getTwoDigitSecond = function() {
          return (this.getSeconds() < 10) ? '0' + this.getSeconds() : this.getSeconds();
      };
  
      Date.prototype.getAbbrevMonthName = function() {
          return typeof window.CalendarNamespace === "undefined"
              ? this.getTwoDigitMonth()
              : window.CalendarNamespace.monthsOfYearAbbrev[this.getMonth()];
      };
  
      Date.prototype.getFullMonthName = function() {
          return typeof window.CalendarNamespace === "undefined"
              ? this.getTwoDigitMonth()
              : window.CalendarNamespace.monthsOfYear[this.getMonth()];
      };
  
      Date.prototype.strftime = function(format) {
          const fields = {
              b: this.getAbbrevMonthName(),
              B: this.getFullMonthName(),
              c: this.toString(),
              d: this.getTwoDigitDate(),
              H: this.getTwoDigitHour(),
              I: this.getTwoDigitTwelveHour(),
              m: this.getTwoDigitMonth(),
              M: this.getTwoDigitMinute(),
              p: (this.getHours() >= 12) ? 'PM' : 'AM',
              S: this.getTwoDigitSecond(),
              w: '0' + this.getDay(),
              x: this.toLocaleDateString(),
              X: this.toLocaleTimeString(),
              y: ('' + this.getFullYear()).substr(2, 4),
              Y: '' + this.getFullYear(),
              '%': '%'
          };
          let result = '', i = 0;
          while (i < format.length) {
              if (format.charAt(i) === '%') {
                  result = result + fields[format.charAt(i + 1)];
                  ++i;
              }
              else {
                  result = result + format.charAt(i);
              }
              ++i;
          }
          return result;
      };
  
      // ----------------------------------------------------------------------------
      // String object extensions
      // ----------------------------------------------------------------------------
      String.prototype.strptime = function(format) {
          const split_format = format.split(/[.\-/]/);
          const date = this.split(/[.\-/]/);
          let i = 0;
          let day, month, year;
          while (i < split_format.length) {
              switch (split_format[i]) {
              case "%d":
                  day = date[i];
                  break;
              case "%m":
                  month = date[i] - 1;
                  break;
              case "%Y":
                  year = date[i];
                  break;
              case "%y":
                  // A %y value in the range of [00, 68] is in the current
                  // century, while [69, 99] is in the previous century,
                  // according to the Open Group Specification.
                  if (parseInt(date[i], 10) >= 69) {
                      year = date[i];
                  } else {
                      year = (new Date(Date.UTC(date[i], 0))).getUTCFullYear() + 100;
                  }
                  break;
              }
              ++i;
          }
          // Create Date object from UTC since the parsed value is supposed to be
          // in UTC, not local time. Also, the calendar uses UTC functions for
          // date extraction.
          return new Date(Date.UTC(year, month, day));
      };
  }
  