var MyAjaxAutocompleter = { }
MyAjaxAutocompleter.Base = Class.create({
  baseInitialize: function(element, update, options) {
    element          = $(element)
    this.element     = element;
    this.update      = $(update);  
    this.hasFocus    = false;
    this.changed     = false;
    this.active      = false;
    this.index       = 0;     
    this.entryCount  = 0;
    this.oldElementValue = this.element.value;

    if(this.setOptions)
      this.setOptions(options);
    else
      this.options = options || { };

    this.options.paramName    = this.options.paramName || this.element.name;
    this.options.tokens       = this.options.tokens || [];
    this.options.frequency    = this.options.frequency || 0.4;
    this.options.minChars     = this.options.minChars || 1;
    this.options.onShow       = this.options.onShow ||
      function(element, update){
        if(!update.style.position || update.style.position=='absolute') {
          update.style.position = 'absolute';
          Position.clone(element, update, {
            setHeight: false,
            offsetTop: element.offsetHeight
          });
        }
        Effect.Appear(update,{duration:0.15});
      };
    this.options.onHide = this.options.onHide ||
      function(element, update){ new Effect.Fade(update,{duration:0.15}) };

    if(typeof(this.options.tokens) == 'string')
      this.options.tokens = new Array(this.options.tokens);
   
    // Force carriage returns as token delimiters anyway
    if (!this.options.tokens.include('\n'))
      this.options.tokens.push('\n');
   
    this.observer = null;
   
    this.element.setAttribute('autocomplete','off');

    Element.hide(this.update);

    Event.observe(this.element, 'blur', this.onBlur.bindAsEventListener(this));
    Event.observe(this.element, 'keydown', this.onKeyPress.bindAsEventListener(this));
  },

  show: function() {
    if(Element.getStyle(this.update, 'display')=='none') this.options.onShow(this.element, this.update);
    if(!this.iefix &&
      (Prototype.Browser.IE) &&
      (Element.getStyle(this.update, 'position')=='absolute')) {
      new Insertion.After(this.update,
       '<iframe id="' + this.update.id + '_iefix" '+
       'style="display:none;position:absolute;filter:progid:DXImageTransform.Microsoft.Alpha(opacity=0);" ' +
       'src="javascript:false;" frameborder="0" scrolling="no"></iframe>');
      this.iefix = $(this.update.id+'_iefix');
    }
    if(this.iefix) setTimeout(this.fixIEOverlapping.bind(this), 50);
  },
 
  fixIEOverlapping: function() {
    Position.clone(this.update, this.iefix, {setTop:(!this.update.style.height)});
    this.iefix.style.zIndex = 1;
    this.update.style.zIndex = 2;
    Element.show(this.iefix);
  },

  hide: function() {
    this.stopIndicator();
    if(Element.getStyle(this.update, 'display')!='none') this.options.onHide(this.element, this.update);
    if(this.iefix) Element.hide(this.iefix);
  },

  startIndicator: function() {
    if(this.options.indicator) Element.show(this.options.indicator);
  },

  stopIndicator: function() {
    if(this.options.indicator) Element.hide(this.options.indicator);
  },

  onKeyPress: function(event) {
    if(this.active)
      switch(event.keyCode) {
       case Event.KEY_TAB:
       case Event.KEY_RETURN:
         this.selectEntry();
         Event.stop(event);
       case Event.KEY_ESC:
         this.hide();
         this.active = false;
         Event.stop(event);
         return;
       case Event.KEY_LEFT:
       case Event.KEY_RIGHT:
         return;
       case Event.KEY_UP:
         this.markPrevious();
         this.render();
         if(Prototype.Browser.WebKit) Event.stop(event);
         return;
       case Event.KEY_DOWN:
         this.markNext();
         this.render();
         if(Prototype.Browser.WebKit) Event.stop(event);
         return;
      }
     else
       if(event.keyCode==Event.KEY_TAB || event.keyCode==Event.KEY_RETURN ||
         (Prototype.Browser.WebKit > 0 && event.keyCode == 0)) return;

    this.changed = true;
    this.hasFocus = true;

    if(this.observer) clearTimeout(this.observer);
      this.observer =
        setTimeout(this.onObserverEvent.bind(this), this.options.frequency*1000);
  },

  activate: function() {
    this.changed = false;
    this.hasFocus = true;
    this.getUpdatedChoices();
  },

  onHover: function(event) {
    var element = Event.findElement(event, 'LI');
    if(this.index != element.autocompleteIndex)
    {
        this.index = element.autocompleteIndex;
        this.render();
    }
    Event.stop(event);
  },
 
  onClick: function(event) {
    var element = Event.findElement(event, 'LI');
    this.index = element.autocompleteIndex;
    this.selectEntry();
    this.hide();
  },
 
  onBlur: function(event) {
    // needed to make click events working
    setTimeout(this.hide.bind(this), 250);
    this.hasFocus = false;
    this.active = false;    
  },
 
  render: function() {
    if(this.entryCount > 0) {
      for (var i = 0; i < this.entryCount; i++)
        this.index==i ?
          Element.addClassName(this.getEntry(i),"selected") :
          Element.removeClassName(this.getEntry(i),"selected");
      if(this.hasFocus) {
        this.show();
        this.active = true;
      }
    } else {
      this.active = false;
      this.hide();
    }
  },
 
  markPrevious: function() {
    if(this.index > 0) this.index--
      else this.index = this.entryCount-1;
    this.getEntry(this.index).scrollIntoView(true);
  },
 
  markNext: function() {
    if(this.index < this.entryCount-1) this.index++
      else this.index = 0;
    this.getEntry(this.index).scrollIntoView(false);
  },
 
  getEntry: function(index) {
    return this.update.firstChild.childNodes[index];
  },
 
  getCurrentEntry: function() {
    return this.getEntry(this.index);
  },
 
  selectEntry: function() {
    this.active = false;
    this.updateElement(this.getCurrentEntry());
  },

  updateElement: function(selectedElement) {
    if (this.options.updateElement) {
      this.options.updateElement(selectedElement);
      return;
    }
    var value = '';
    if (this.options.select) {
      var nodes = $(selectedElement).select('.' + this.options.select) || [];
      if(nodes.length>0) value = Element.collectTextNodes(nodes[0], this.options.select);
    } else
      value = Element.collectTextNodesIgnoreClass(selectedElement, 'informal');
   
    var bounds = this.getTokenBounds();
    if (bounds[0] != -1) {
      var newValue = this.element.value.substr(0, bounds[0]);
      var whitespace = this.element.value.substr(bounds[0]).match(/^\s+/);
      if (whitespace)
        newValue += whitespace[0];
      this.element.value = newValue + value + this.element.value.substr(bounds[1]);
    } else {
      this.element.value = value;
    }
    this.oldElementValue = this.element.value;
    this.element.focus();
   
    if (this.options.afterUpdateElement)
      this.options.afterUpdateElement(this.element, selectedElement);
  },

  updateChoices: function(choices) {
 
   if(!this.changed && this.hasFocus) {
   //JML: customization: JSON -> HTML
    var out = this.choicesToHtml(eval('(' + choices + ')'));
      this.update.innerHTML = out; // choices;
   
     
      Element.cleanWhitespace(this.update);
      Element.cleanWhitespace(this.update.down());

      if(this.update.firstChild && this.update.down().childNodes) {
        this.entryCount =
          this.update.down().childNodes.length;
        for (var i = 0; i < this.entryCount; i++) {
          var entry = this.getEntry(i);
          entry.autocompleteIndex = i;
          this.addObservers(entry);
        }
      } else {
        this.entryCount = 0;
      }

      this.stopIndicator();
      this.index = 0;
     
      if(this.entryCount==1 && this.options.autoSelect) {
        this.selectEntry();
        this.hide();
      } else {
        this.render();
      }
    }
  },

  addObservers: function(element) {
    Event.observe(element, "mouseover", this.onHover.bindAsEventListener(this));
    Event.observe(element, "click", this.onClick.bindAsEventListener(this));
  },

  onObserverEvent: function() {
    this.changed = false;  
    this.tokenBounds = null;
    if(this.getToken().length>=this.options.minChars) {
      this.getUpdatedChoices();
    } else {
      this.active = false;
      this.hide();
    }
    this.oldElementValue = this.element.value;
  },

  getToken: function() {
    var bounds = this.getTokenBounds();
    return this.element.value.substring(bounds[0], bounds[1]).strip();
  },

  getTokenBounds: function() {
    if (null != this.tokenBounds) return this.tokenBounds;
    var value = this.element.value;
    if (value.strip().empty()) return [-1, 0];
    var diff = arguments.callee.getFirstDifferencePos(value, this.oldElementValue);
    var offset = (diff == this.oldElementValue.length ? 1 : 0);
    var prevTokenPos = -1, nextTokenPos = value.length;
    var tp;
    for (var index = 0, l = this.options.tokens.length; index < l; ++index) {
      tp = value.lastIndexOf(this.options.tokens[index], diff + offset - 1);
      if (tp > prevTokenPos) prevTokenPos = tp;
      tp = value.indexOf(this.options.tokens[index], diff + offset);
      if (-1 != tp && tp < nextTokenPos) nextTokenPos = tp;
    }
    return (this.tokenBounds = [prevTokenPos + 1, nextTokenPos]);
  },
  //JML: render the choices into the div
  choicesToHtml : function(choices)
  {
    var output = "<ul>";
        for (i=0; i< choices.length; i++)
            output = output + "<li>" + choices[i] + "</li>";
       
    return output + "</ul>";      
  }
});

MyAjaxAutocompleter.Base.prototype.getTokenBounds.getFirstDifferencePos = function(newS, oldS) {
  var boundary = Math.min(newS.length, oldS.length);
  for (var index = 0; index < boundary; ++index)
    if (newS[index] != oldS[index])
      return index;
  return boundary;
};

MyAjaxAutocompleter = Class.create(MyAjaxAutocompleter.Base, {
  initialize: function(element, update, url, options) {
    this.baseInitialize(element, update, options);
   
    this.options.asynchronous  = true;
    this.options.onComplete    = this.onComplete.bind(this);
    //added a default contentType of json:
    //this.options.contentType = "application/json; charset=utf-8";
   
    this.options.defaultParams = null;
    this.url                   = url;
   
  },

  getUpdatedChoices: function() {
    this.startIndicator();
   
    var entry = encodeURIComponent(this.options.paramName) + '=' +
      encodeURIComponent(this.getToken());

    this.options.parameters = this.options.callback ?
      this.options.callback(this.element, entry) : entry;

    if(this.options.defaultParams)
      this.options.parameters += '&' + this.options.defaultParams;
   
    //JML: added for support of the autocomplete widget. This gets passed to the webservice:
    this.options.parameters   += "&search="+this.element.value;

    new Ajax.Request(this.url, this.options);



  },
  
  onComplete: function(request) {
    this.updateChoices(request.responseText);
  }
});
