Effect.Tooltip = Class.create();
Object.extend(Object.extend(Effect.Tooltip.prototype, Effect.Base.prototype), {
  initialize: function(element, content) {
    this.element = $(element);
    if(!this.element) throw(Effect._elementDoesNotExistError);
    var options = Object.extend({
      content: content,
      title: false,
      className: 'tooltip',
      offset: {'x':16, 'y':16}
    }, arguments[2] || {});
    this.start(options);
  },
  setup: function() {
    // create a wrapper
    this.wrapper = document.createElement('div');
    this.wrapper.className = this.options.className;
    Element.setStyle(this.wrapper, {
      position: 'absolute',
      display: 'none'
    });
    // add the title
    if(this.options.title) {
      var title = document.createElement('div');
      title.className = 'title';
      Element.update(title, this.options.title);
      this.wrapper.appendChild(title);
    }
    // create the actual tooltip
    this.tip = document.createElement('div');
    this.tip.className = 'content';
    Element.update(this.tip, this.options.content);
    this.wrapper.appendChild(this.tip);
		
		
		// add the arrow span
		this.arrow = document.createElement('span');
    this.arrow.className = 'arrow';
    Element.update(this.arrow, ' ');
    this.wrapper.appendChild(this.arrow);
		
    // add wrapper to the body
    document.body.appendChild(this.wrapper);

    // add observers
    this.element.observe('mouseover', this.showTip.bind(this));
    //this.element.observe('mousemove', this.showTip.bind(this));
    this.element.observe('mouseout', this.hideTip.bind(this));
  },
  showTip: function(event){
    //this.positionTip(event);
    this.positionTip2();
    this.wrapper.show();
  },
  hideTip: function(){
    this.wrapper.hide();
  },
	
	
	viewportDimensions: function(){
		var de = document.documentElement;
		var w = window.innerWidth || self.innerWidth || (de&&de.clientWidth) || document.body.clientWidth;
		var h = window.innerHeight || self.innerHeight || (de&&de.clientHeight) || document.body.clientHeight;
		return {xWidth: w, yHeight: h};		
	},
	
	positionTip2: function() {
		var arrow = this.arrow;//$(gtip).down('span.gtip-arrow');
		arrow.removeClassName('arrow-left','arrow-right');
		
		var viewport = this.viewportDimensions();
		var eltpos   = Position.cumulativeOffset(this.element);
		var xWidth   = 200;
		if (viewport.xWidth>(eltpos[0]+this.element.getWidth()+xWidth)){
			var left = eltpos[0] + this.element.getWidth() + 15;
			arrow.addClassName('arrow-left');
			arrow.setStyle({left:'-10px'});
		} else {
			var left = eltpos[0] - (xWidth*1+15);
			arrow.addClassName('arrow-right');
			arrow.setStyle({left:xWidth+'px'});
		}
		this.wrapper.setStyle({
			width:xWidth+'px',
			top:(eltpos[1]-10)+'px',
			left:left+'px'});
	},
  positionTip: function(event){
    var offsets = {'x': this.options.offset['x'],'y': this.options.offset['y']};
    var mouse = {'x': Event.pointerX(event), 'y': Event.pointerY(event)};
    var page = {'x':this.viewportSize()['x'], 'y':this.viewportSize()['y']};
    var tip = {'x': mouse['x'] + this.options.offset['x'] + this.wrapper.getWidth(),
    'y' : mouse['y'] + this.options.offset['y'] + this.wrapper.getHeight()};

    // inverse x or y to keep tooltip within viewport
    if(tip['x']>page['x']) { offsets['x'] = 0-(this.wrapper.getWidth() + this.options.offset['x']); }
    if(tip['y']>page['y']) { offsets['y'] = 0-(this.wrapper.getHeight() + this.options.offset['y']); }

    this.wrapper.setStyle({
      left: mouse['x'] + offsets['x'] + 'px',
      top: mouse['y'] + offsets['y'] + 'px'
    });
  },
  viewportSize : function(){
    if (self.innerHeight) return {'x': self.innerWidth, 'y': self.innerHeight};
    else if (document.documentElement && document.documentElement.clientHeight)
    return {'x': document.documentElement.clientWidth, 'y': document.documentElement.clientHeight};
    else if (document.body) return {'x': document.body.clientWidth, 'y': document.body.clientHeight};
  }
});