text: /**
   * Provides the Calendar class.
   *
   * @module moodle-form-dateselector
   */
  
  /**
   * Calendar class
   */
  var CALENDAR = function() {
      CALENDAR.superclass.constructor.apply(this, arguments);
  };
  CALENDAR.prototype = {
      panel: null,
      yearselect: null,
      monthselect: null,
      dayselect: null,
      calendarimage: null,
      enablecheckbox: null,
      closepopup: true,
      initializer: function() {
          var controls = this.get('node').all('select');
          controls.each(function(node) {
              if (node.get('name').match(/\[year\]/)) {
                  this.yearselect = node;
              } else if (node.get('name').match(/\[month\]/)) {
                  this.monthselect = node;
              } else if (node.get('name').match(/\[day\]/)) {
                  this.dayselect = node;
              }
              node.after('change', this.handle_select_change, this);
          }, this);
  
          // Loop through the input fields.
          var inputs = this.get('node').all('input, a');
          inputs.each(function(node) {
              // Check if the current node is a calendar image field.
              if (node.get('name').match(/\[calendar\]/)) {
                  // Set it so that when the image is clicked the pop-up displays.
                  node.on('click', this.focus_event, this);
                  // Set the node to the calendarimage variable.
                  this.calendarimage = node;
              } else { // Must be the enabled checkbox field.
                  // If the enable checkbox is clicked we want to either disable/enable the calendar image.
                  node.on('click', this.toggle_calendar_image, this);
                  // Set the node to the enablecheckbox variable.
                  this.enablecheckbox = node;
              }
              // Ensure that the calendarimage and enablecheckbox values have been set.
              if (this.calendarimage && this.enablecheckbox) {
                  // Set the calendar icon status depending on the value of the checkbox.
                  this.toggle_calendar_image();
              }
          }, this);
      },
      focus_event: function(e) {
          M.form.dateselector.cancel_any_timeout();
          // If the current owner is set, then the pop-up is currently being displayed, so hide it.
          if (M.form.dateselector.currentowner === this) {
              this.release_calendar();
          } else if ((this.enablecheckbox === null)
              || (this.enablecheckbox.get('checked'))) { // Must be hidden. If the field is enabled display the pop-up.
              this.claim_calendar();
          }
          // Stop the input image field from submitting the form.
          e.preventDefault();
      },
      handle_select_change: function() {
          // It may seem as if the following variable is not used, however any call to set_date_from_selects will trigger a
          // call to set_selects_from_date if the calendar is open as the date has changed. Whenever the calendar is displayed
          // the set_selects_from_date function is set to trigger on any date change (see function connect_handlers).
          this.closepopup = false;
          this.set_date_from_selects();
          this.closepopup = true;
      },
      claim_calendar: function() {
          M.form.dateselector.cancel_any_timeout();
          if (M.form.dateselector.currentowner === this) {
              return;
          }
          if (M.form.dateselector.currentowner) {
              M.form.dateselector.currentowner.release_calendar();
          }
          if (M.form.dateselector.currentowner !== this) {
              this.connect_handlers();
              this.set_date_from_selects();
          }
          M.form.dateselector.currentowner = this;
          M.form.dateselector.calendar.set('mindate', new Date(this.yearselect.firstOptionValue(), 0, 1));
          M.form.dateselector.calendar.set('maxdate', new Date(this.yearselect.lastOptionValue(), 11, 31));
          M.form.dateselector.panel.show();
          M.form.dateselector.calendar.show();
          M.form.dateselector.fix_position();
          setTimeout(function() {
              M.form.dateselector.cancel_any_timeout();
          }, 100);
  
          // Focus on the calendar.
          M.form.dateselector.calendar.focus();
  
          // When the user tab out the calendar, close it.
          Y.one(document.body).on('keyup', function(e) {
              // hide the calendar if we press a key and the calendar is not focussed, or if we press ESC in the calendar.
              if ((M.form.dateselector.currentowner === this && !M.form.dateselector.calendar.get('focused')) ||
                  ((e.keyCode === 27) && M.form.dateselector.calendar.get('focused'))) {
                  // Focus back on the calendar button.
                  this.calendarimage.focus();
                  this.release_calendar();
              }
          }, this);
  
      },
      set_date_from_selects: function() {
          var year = parseInt(this.yearselect.get('value'), 10);
          var month = parseInt(this.monthselect.get('value'), 10) - 1;
          var day = parseInt(this.dayselect.get('value'), 10);
          var date = new Date(year, month, day);
          M.form.dateselector.calendar.deselectDates();
          M.form.dateselector.calendar.selectDates([date]);
          M.form.dateselector.calendar.set("date", date);
          M.form.dateselector.calendar.render();
          if (date.getDate() !== day) {
              // Must've selected the 29 to 31st of a month that doesn't have such dates.
              this.dayselect.set('value', date.getDate());
              this.monthselect.set('value', date.getMonth() + 1);
          }
      },
      set_selects_from_date: function(ev) {
          var date = ev.newSelection[0];
          var newyear = Y.DataType.Date.format(date, {format: "%Y"});
          var newindex = newyear - this.yearselect.firstOptionValue();
          this.yearselect.set('selectedIndex', newindex);
          this.monthselect.set('selectedIndex', Y.DataType.Date.format(date, {format: "%m"}) - this.monthselect.firstOptionValue());
          this.dayselect.set('selectedIndex', Y.DataType.Date.format(date, {format: "%d"}) - this.dayselect.firstOptionValue());
          if (M.form.dateselector.currentowner && this.closepopup) {
              this.release_calendar();
          }
      },
      connect_handlers: function() {
          M.form.dateselector.calendar.on('selectionChange', this.set_selects_from_date, this, true);
      },
      release_calendar: function(e) {
          var wasOwner = M.form.dateselector.currentowner === this;
          M.form.dateselector.panel.hide();
          M.form.dateselector.calendar.detach('selectionChange', this.set_selects_from_date);
          M.form.dateselector.calendar.hide();
          M.form.dateselector.currentowner = null;
  
          // Put the focus back to the image calendar that we clicked, only if it was visible.
          if (wasOwner && (e === null || typeof e === "undefined" || e.type !== "click")) {
              this.calendarimage.focus();
          }
      },
      toggle_calendar_image: function() {
          // If the enable checkbox is det checked, disable the image.
          if (!this.enablecheckbox.get('checked')) {
              this.calendarimage.set('disabled', 'disabled');
              this.calendarimage.setStyle('cursor', 'default');
              this.release_calendar();
          } else {
              this.calendarimage.set('disabled', false);
              this.calendarimage.setStyle('cursor', null);
          }
      }
  };
  Y.extend(CALENDAR, Y.Base, CALENDAR.prototype, {
      NAME: 'Date Selector',
      ATTRS: {
          firstdayofweek: {
              validator: Y.Lang.isString
          },
          node: {
              setter: function(node) {
                  return Y.one(node);
              }
          }
      }
  });
  