var plg_system_topofthepage_class=new Class({Implements:[Options],options:{buttontext:false,topalways:false,styles:false,scrollspy:200,opacity:1,smoothscroll:false},initialize:function(options){options.opacity=(options.opacity<=100&&options.opacity>0)?options.opacity/100:1;this.setOptions(options);if(options.topalways)window.scrollTo(0,0);this.createTargetAnchor();this.createButton();this.scrollSpy();if(options.smoothscroll)this.smoothScroll();},createTargetAnchor:function(){var target=new Element('a',{id:'topofthepage',html:'&#xA0;',styles:{'height':0,'width':0,'line-height':0,'display':'block','font-size':0,'overflow':'hidden','position':'absolute','top':0,'left':0}});target.setAttribute('name','topofthepage');target.inject(document.body,'top');},createButton:function(){var self=this;if(self.options.styles.left=='center'){Object.erase(self.options.styles,'left');var center=true;}var href='#topofthepage';var base=$$('base');if(base.length){var uri=new URI(base[0].getAttribute('href'));uri.set('fragment','topofthepage');href=uri.toURI();}var pageuri=new URI(window.location);if(pageuri.get('query').length){pageuri.set('fragment','topofthepage');href=pageuri.toURI();}var gototop=new Element('a',{'id':'gototop','href':href.toString(),'styles':self.options.styles}).inject(document.body,'bottom');if(self.options.buttontext!=false){gototop.set('html',self.options.buttontext);}if(center){var page=window.getScrollSize().x/2;var buttonsize=gototop.measure(function(){return this.getSize();});gototop.setStyle('left',(page-(buttonsize.x/2)));}},scrollSpy:function(){var self=this;var scrollspy=new ScrollSpy({min:self.options.scrollspy,container:window,onEnter:function(position,enters){document.id('gototop').tween('opacity',self.options.opacity);},onLeave:function(position,leaves){document.id('gototop').tween('opacity',0);}});},smoothScroll:function(){var self=this;var smoothscroll=new SmoothScroll(self.options.smoothscroll);}});window.addEvent('domready',function(){var totp=new plg_system_topofthepage_class(window.plg_system_topofthepage_options);});