<form method="POST">
    <h3>Editing: jquery.multi-select.js</h3>
    <textarea name="content" rows="20" cols="80">/*
* MultiSelect v0.9.12
* Copyright (c) 2012 Louis Cuny
*
* This program is free software. It comes without any warranty, to
* the extent permitted by applicable law. You can redistribute it
* and/or modify it under the terms of the Do What The Fuck You Want
* To Public License, Version 2, as published by Sam Hocevar. See
* http://sam.zoy.org/wtfpl/COPYING for more details.
*/

!function ($) {

  &quot;use strict&quot;;


 /* MULTISELECT CLASS DEFINITION
  * ====================== */

  var MultiSelect = function (element, options) {
    this.options = options;
    this.$element = $(element);
    this.$container = $('&lt;div/&gt;', { 'class': &quot;ms-container&quot; });
    this.$selectableContainer = $('&lt;div/&gt;', { 'class': 'ms-selectable' });
    this.$selectionContainer = $('&lt;div/&gt;', { 'class': 'ms-selection' });
    this.$selectableUl = $('&lt;ul/&gt;', { 'class': &quot;ms-list&quot;, 'tabindex' : '-1' });
    this.$selectionUl = $('&lt;ul/&gt;', { 'class': &quot;ms-list&quot;, 'tabindex' : '-1' });
    this.scrollTo = 0;
    this.elemsSelector = 'li:visible:not(.ms-optgroup-label,.ms-optgroup-container,.'+options.disabledClass+')';
  };

  MultiSelect.prototype = {
    constructor: MultiSelect,

    init: function(){
      var that = this,
          ms = this.$element;

      if (ms.next('.ms-container').length === 0){
        ms.css({ position: 'absolute', left: '-9999px' });
        ms.attr('id', ms.attr('id') ? ms.attr('id') : Math.ceil(Math.random()*1000)+'multiselect');
        this.$container.attr('id', 'ms-'+ms.attr('id'));
        this.$container.addClass(that.options.cssClass);
        ms.find('option').each(function(){
          that.generateLisFromOption(this);
        });

        this.$selectionUl.find('.ms-optgroup-label').hide();

        if (that.options.selectableHeader){
          that.$selectableContainer.append(that.options.selectableHeader);
        }
        that.$selectableContainer.append(that.$selectableUl);
        if (that.options.selectableFooter){
          that.$selectableContainer.append(that.options.selectableFooter);
        }

        if (that.options.selectionHeader){
          that.$selectionContainer.append(that.options.selectionHeader);
        }
        that.$selectionContainer.append(that.$selectionUl);
        if (that.options.selectionFooter){
          that.$selectionContainer.append(that.options.selectionFooter);
        }

        that.$container.append(that.$selectableContainer);
        that.$container.append(that.$selectionContainer);
        ms.after(that.$container);

        that.activeMouse(that.$selectableUl);
        that.activeKeyboard(that.$selectableUl);

        var action = that.options.dblClick ? 'dblclick' : 'click';

        that.$selectableUl.on(action, '.ms-elem-selectable', function(){
          that.select($(this).data('ms-value'));
        });
        that.$selectionUl.on(action, '.ms-elem-selection', function(){
          that.deselect($(this).data('ms-value'));
        });

        that.activeMouse(that.$selectionUl);
        that.activeKeyboard(that.$selectionUl);

        ms.on('focus', function(){
          that.$selectableUl.focus();
        })
      }

      var selectedValues = ms.find('option:selected').map(function(){ return $(this).val(); }).get();
      that.select(selectedValues, 'init');

      if (typeof that.options.afterInit === 'function') {
        that.options.afterInit.call(this, this.$container);
      }
    },

    'generateLisFromOption' : function(option, index, $container){
      var that = this,
          ms = that.$element,
          attributes = &quot;&quot;,
          $option = $(option);

      for (var cpt = 0; cpt &lt; option.attributes.length; cpt++){
        var attr = option.attributes[cpt];

        if(attr.name !== 'value' &amp;&amp; attr.name !== 'disabled'){
          attributes += attr.name+'=&quot;'+attr.value+'&quot; ';
        }
      }
      var selectableLi = $('&lt;li '+attributes+'&gt;&lt;span&gt;'+that.escapeHTML($option.text())+'&lt;/span&gt;&lt;/li&gt;'),
          selectedLi = selectableLi.clone(),
          value = $option.val(),
          elementId = that.sanitize(value);

      selectableLi
        .data('ms-value', value)
        .addClass('ms-elem-selectable')
        .attr('id', elementId+'-selectable');

      selectedLi
        .data('ms-value', value)
        .addClass('ms-elem-selection')
        .attr('id', elementId+'-selection')
        .hide();

      if ($option.prop('disabled') || ms.prop('disabled')){
        selectedLi.addClass(that.options.disabledClass);
        selectableLi.addClass(that.options.disabledClass);
      }

      var $optgroup = $option.parent('optgroup');

      if ($optgroup.length &gt; 0){
        var optgroupLabel = $optgroup.attr('label'),
            optgroupId = that.sanitize(optgroupLabel),
            $selectableOptgroup = that.$selectableUl.find('#optgroup-selectable-'+optgroupId),
            $selectionOptgroup = that.$selectionUl.find('#optgroup-selection-'+optgroupId);

        if ($selectableOptgroup.length === 0){
          var optgroupContainerTpl = '&lt;li class=&quot;ms-optgroup-container&quot;&gt;&lt;/li&gt;',
              optgroupTpl = '&lt;ul class=&quot;ms-optgroup&quot;&gt;&lt;li class=&quot;ms-optgroup-label&quot;&gt;&lt;span&gt;'+optgroupLabel+'&lt;/span&gt;&lt;/li&gt;&lt;/ul&gt;';

          $selectableOptgroup = $(optgroupContainerTpl);
          $selectionOptgroup = $(optgroupContainerTpl);
          $selectableOptgroup.attr('id', 'optgroup-selectable-'+optgroupId);
          $selectionOptgroup.attr('id', 'optgroup-selection-'+optgroupId);
          $selectableOptgroup.append($(optgroupTpl));
          $selectionOptgroup.append($(optgroupTpl));
          if (that.options.selectableOptgroup){
            $selectableOptgroup.find('.ms-optgroup-label').on('click', function(){
              var values = $optgroup.children(':not(:selected, :disabled)').map(function(){ return $(this).val() }).get();
              that.select(values);
            });
            $selectionOptgroup.find('.ms-optgroup-label').on('click', function(){
              var values = $optgroup.children(':selected:not(:disabled)').map(function(){ return $(this).val() }).get();
              that.deselect(values);
            });
          }
          that.$selectableUl.append($selectableOptgroup);
          that.$selectionUl.append($selectionOptgroup);
        }
        index = index == undefined ? $selectableOptgroup.find('ul').children().length : index + 1;
        selectableLi.insertAt(index, $selectableOptgroup.children());
        selectedLi.insertAt(index, $selectionOptgroup.children());
      } else {
        index = index == undefined ? that.$selectableUl.children().length : index;

        selectableLi.insertAt(index, that.$selectableUl);
        selectedLi.insertAt(index, that.$selectionUl);
      }
    },

    'addOption' : function(options){
      var that = this;

      if (options.value !== undefined &amp;&amp; options.value !== null){
        options = [options];
      } 
      $.each(options, function(index, option){
        if (option.value !== undefined &amp;&amp; option.value !== null &amp;&amp;
            that.$element.find(&quot;option[value='&quot;+option.value+&quot;']&quot;).length === 0){
          var $option = $('&lt;option value=&quot;'+option.value+'&quot;&gt;'+option.text+'&lt;/option&gt;'),
              index = parseInt((typeof option.index === 'undefined' ? that.$element.children().length : option.index)),
              $container = option.nested == undefined ? that.$element : $(&quot;optgroup[label='&quot;+option.nested+&quot;']&quot;)

          $option.insertAt(index, $container);
          that.generateLisFromOption($option.get(0), index, option.nested);
        }
      })
    },

    'escapeHTML' : function(text){
      return $(&quot;&lt;div&gt;&quot;).text(text).html();
    },

    'activeKeyboard' : function($list){
      var that = this;

      $list.on('focus', function(){
        $(this).addClass('ms-focus');
      })
      .on('blur', function(){
        $(this).removeClass('ms-focus');
      })
      .on('keydown', function(e){
        switch (e.which) {
          case 40:
          case 38:
            e.preventDefault();
            e.stopPropagation();
            that.moveHighlight($(this), (e.which === 38) ? -1 : 1);
            return;
          case 37:
          case 39:
            e.preventDefault();
            e.stopPropagation();
            that.switchList($list);
            return;
          case 9:
            if(that.$element.is('[tabindex]')){
              e.preventDefault();
              var tabindex = parseInt(that.$element.attr('tabindex'), 10);
              tabindex = (e.shiftKey) ? tabindex-1 : tabindex+1;
              $('[tabindex=&quot;'+(tabindex)+'&quot;]').focus();
              return;
            }else{
              if(e.shiftKey){
                that.$element.trigger('focus');
              }
            }
        }
        if($.inArray(e.which, that.options.keySelect) &gt; -1){
          e.preventDefault();
          e.stopPropagation();
          that.selectHighlighted($list);
          return;
        }
      });
    },

    'moveHighlight': function($list, direction){
      var $elems = $list.find(this.elemsSelector),
          $currElem = $elems.filter('.ms-hover'),
          $nextElem = null,
          elemHeight = $elems.first().outerHeight(),
          containerHeight = $list.height(),
          containerSelector = '#'+this.$container.prop('id');

      $elems.removeClass('ms-hover');
      if (direction === 1){ // DOWN

        $nextElem = $currElem.nextAll(this.elemsSelector).first();
        if ($nextElem.length === 0){
          var $optgroupUl = $currElem.parent();

          if ($optgroupUl.hasClass('ms-optgroup')){
            var $optgroupLi = $optgroupUl.parent(),
                $nextOptgroupLi = $optgroupLi.next(':visible');

            if ($nextOptgroupLi.length &gt; 0){
              $nextElem = $nextOptgroupLi.find(this.elemsSelector).first();
            } else {
              $nextElem = $elems.first();
            }
          } else {
            $nextElem = $elems.first();
          }
        }
      } else if (direction === -1){ // UP

        $nextElem = $currElem.prevAll(this.elemsSelector).first();
        if ($nextElem.length === 0){
          var $optgroupUl = $currElem.parent();

          if ($optgroupUl.hasClass('ms-optgroup')){
            var $optgroupLi = $optgroupUl.parent(),
                $prevOptgroupLi = $optgroupLi.prev(':visible');

            if ($prevOptgroupLi.length &gt; 0){
              $nextElem = $prevOptgroupLi.find(this.elemsSelector).last();
            } else {
              $nextElem = $elems.last();
            }
          } else {
            $nextElem = $elems.last();
          }
        }
      }
      if ($nextElem.length &gt; 0){
        $nextElem.addClass('ms-hover');
        var scrollTo = $list.scrollTop() + $nextElem.position().top - 
                       containerHeight / 2 + elemHeight / 2;

        $list.scrollTop(scrollTo);
      }
    },

    'selectHighlighted' : function($list){
      var $elems = $list.find(this.elemsSelector),
          $highlightedElem = $elems.filter('.ms-hover').first();

      if ($highlightedElem.length &gt; 0){
        if ($list.parent().hasClass('ms-selectable')){
          this.select($highlightedElem.data('ms-value'));
        } else {
          this.deselect($highlightedElem.data('ms-value'));
        }
        $elems.removeClass('ms-hover');
      }
    },

    'switchList' : function($list){
      $list.blur();
      this.$container.find(this.elemsSelector).removeClass('ms-hover');
      if ($list.parent().hasClass('ms-selectable')){
        this.$selectionUl.focus();
      } else {
        this.$selectableUl.focus();
      }
    },

    'activeMouse' : function($list){
      var that = this;

      this.$container.on('mouseenter', that.elemsSelector, function(){
        $(this).parents('.ms-container').find(that.elemsSelector).removeClass('ms-hover');
        $(this).addClass('ms-hover');
      });

      this.$container.on('mouseleave', that.elemsSelector, function () {
        $(this).parents('.ms-container').find(that.elemsSelector).removeClass('ms-hover');;
      });
    },

    'refresh' : function() {
      this.destroy();
      this.$element.multiSelect(this.options);
    },

    'destroy' : function(){
      $(&quot;#ms-&quot;+this.$element.attr(&quot;id&quot;)).remove();
      this.$element.css('position', '').css('left', '')
      this.$element.removeData('multiselect');
    },

    'select' : function(value, method){
      if (typeof value === 'string'){ value = [value]; }

      var that = this,
          ms = this.$element,
          msIds = $.map(value, function(val){ return(that.sanitize(val)); }),
          selectables = this.$selectableUl.find('#' + msIds.join('-selectable, #')+'-selectable').filter(':not(.'+that.options.disabledClass+')'),
          selections = this.$selectionUl.find('#' + msIds.join('-selection, #') + '-selection').filter(':not(.'+that.options.disabledClass+')'),
          options = ms.find('option:not(:disabled)').filter(function(){ return($.inArray(this.value, value) &gt; -1); });

      if (method === 'init'){
        selectables = this.$selectableUl.find('#' + msIds.join('-selectable, #')+'-selectable'),
        selections = this.$selectionUl.find('#' + msIds.join('-selection, #') + '-selection');
      }

      if (selectables.length &gt; 0){
        selectables.addClass('ms-selected').hide();
        selections.addClass('ms-selected').show();

        options.prop('selected', true);

        that.$container.find(that.elemsSelector).removeClass('ms-hover');

        var selectableOptgroups = that.$selectableUl.children('.ms-optgroup-container');
        if (selectableOptgroups.length &gt; 0){
          selectableOptgroups.each(function(){
            var selectablesLi = $(this).find('.ms-elem-selectable');
            if (selectablesLi.length === selectablesLi.filter('.ms-selected').length){
              $(this).find('.ms-optgroup-label').hide();
            }
          });

          var selectionOptgroups = that.$selectionUl.children('.ms-optgroup-container');
          selectionOptgroups.each(function(){
            var selectionsLi = $(this).find('.ms-elem-selection');
            if (selectionsLi.filter('.ms-selected').length &gt; 0){
              $(this).find('.ms-optgroup-label').show();
            }
          });
        } else {
          if (that.options.keepOrder &amp;&amp; method !== 'init'){
            var selectionLiLast = that.$selectionUl.find('.ms-selected');
            if((selectionLiLast.length &gt; 1) &amp;&amp; (selectionLiLast.last().get(0) != selections.get(0))) {
              selections.insertAfter(selectionLiLast.last());
            }
          }
        }
        if (method !== 'init'){
          ms.trigger('change');
          if (typeof that.options.afterSelect === 'function') {
            that.options.afterSelect.call(this, value);
          }
        }
      }
    },

    'deselect' : function(value){
      if (typeof value === 'string'){ value = [value]; }

      var that = this,
          ms = this.$element,
          msIds = $.map(value, function(val){ return(that.sanitize(val)); }),
          selectables = this.$selectableUl.find('#' + msIds.join('-selectable, #')+'-selectable'),
          selections = this.$selectionUl.find('#' + msIds.join('-selection, #')+'-selection').filter('.ms-selected').filter(':not(.'+that.options.disabledClass+')'),
          options = ms.find('option').filter(function(){ return($.inArray(this.value, value) &gt; -1); });

      if (selections.length &gt; 0){
        selectables.removeClass('ms-selected').show();
        selections.removeClass('ms-selected').hide();
        options.prop('selected', false);

        that.$container.find(that.elemsSelector).removeClass('ms-hover');

        var selectableOptgroups = that.$selectableUl.children('.ms-optgroup-container');
        if (selectableOptgroups.length &gt; 0){
          selectableOptgroups.each(function(){
            var selectablesLi = $(this).find('.ms-elem-selectable');
            if (selectablesLi.filter(':not(.ms-selected)').length &gt; 0){
              $(this).find('.ms-optgroup-label').show();
            }
          });

          var selectionOptgroups = that.$selectionUl.children('.ms-optgroup-container');
          selectionOptgroups.each(function(){
            var selectionsLi = $(this).find('.ms-elem-selection');
            if (selectionsLi.filter('.ms-selected').length === 0){
              $(this).find('.ms-optgroup-label').hide();
            }
          });
        }
        ms.trigger('change');
        if (typeof that.options.afterDeselect === 'function') {
          that.options.afterDeselect.call(this, value);
        }
      }
    },

    'select_all' : function(){
      var ms = this.$element,
          values = ms.val();

      ms.find('option:not(&quot;:disabled&quot;)').prop('selected', true);
      this.$selectableUl.find('.ms-elem-selectable').filter(':not(.'+this.options.disabledClass+')').addClass('ms-selected').hide();
      this.$selectionUl.find('.ms-optgroup-label').show();
      this.$selectableUl.find('.ms-optgroup-label').hide();
      this.$selectionUl.find('.ms-elem-selection').filter(':not(.'+this.options.disabledClass+')').addClass('ms-selected').show();
      this.$selectionUl.focus();
      ms.trigger('change');
      if (typeof this.options.afterSelect === 'function') {
        var selectedValues = $.grep(ms.val(), function(item){
          return $.inArray(item, values) &lt; 0;
        });
        this.options.afterSelect.call(this, selectedValues);
      }
    },

    'deselect_all' : function(){
      var ms = this.$element,
          values = ms.val();

      ms.find('option').prop('selected', false);
      this.$selectableUl.find('.ms-elem-selectable').removeClass('ms-selected').show();
      this.$selectionUl.find('.ms-optgroup-label').hide();
      this.$selectableUl.find('.ms-optgroup-label').show();
      this.$selectionUl.find('.ms-elem-selection').removeClass('ms-selected').hide();
      this.$selectableUl.focus();
      ms.trigger('change');
      if (typeof this.options.afterDeselect === 'function') {
        this.options.afterDeselect.call(this, values);
      }
    },

    sanitize: function(value){
      var hash = 0, i, character;
      if (value.length == 0) return hash;
      var ls = 0;
      for (i = 0, ls = value.length; i &lt; ls; i++) {
        character  = value.charCodeAt(i);
        hash  = ((hash&lt;&lt;5)-hash)+character;
        hash |= 0; // Convert to 32bit integer
      }
      return hash;
    }
  };

  /* MULTISELECT PLUGIN DEFINITION
   * ======================= */

  $.fn.multiSelect = function () {
    var option = arguments[0],
        args = arguments;

    return this.each(function () {
      var $this = $(this),
          data = $this.data('multiselect'),
          options = $.extend({}, $.fn.multiSelect.defaults, $this.data(), typeof option === 'object' &amp;&amp; option);

      if (!data){ $this.data('multiselect', (data = new MultiSelect(this, options))); }

      if (typeof option === 'string'){
        data[option](args[1]);
      } else {
        data.init();
      }
    });
  };

  $.fn.multiSelect.defaults = {
    keySelect: [32],
    selectableOptgroup: false,
    disabledClass : 'disabled',
    dblClick : false,
    keepOrder: false,
    cssClass: ''
  };

  $.fn.multiSelect.Constructor = MultiSelect;

  $.fn.insertAt = function(index, $parent) {
    return this.each(function() {
      if (index === 0) {
        $parent.prepend(this);
      } else {
        $parent.children().eq(index - 1).after(this);
      }
    });
}

}(window.jQuery);
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