//** jQuery Scroll to Top Control script- (c) Dynamic Drive DHTML code library: http://www.dynamicdrive.com.
//** Available/ usage terms at http://www.dynamicdrive.com (March 30th, 09')

var scrolltotop={
	setting: {startline:200, scrollduration:1000, fadeduration:[500, 100]}, //startline=number of pixels from top of doc scrollbar is at before showing control
	controlHTML: '<img src="http://research.binghamton.edu/images2/icons/Top.gif" style="width:40px; height:14px" />', //HTML for control, which is auto wrapped in DIV w/ ID="topcontrol"
	controlattrs: {offsetx:15, offsety:15}, //offset of control relative to right/ bottom of window corner
	anchorkeyword: '#top', //Enter href value of HTML anchors on the page that should also act as "Scroll Up" links

	state: {isvisible:false, shouldvisible:false},

	scrollup:function(){
		if (!this.cssfixedsupport)
			this.$control.css({opacity:0})
		this.$body.animate({scrollTop: 0}, this.setting.scrollduration);
	},

	keepfixed:function(){
	var $window=jQuery(window)
		//set the x and y co-ordinates for the control
		var controlx=$window.scrollLeft() + $window.width() - this.$control.width() - this.controlattrs.offsetx
		var controly=$window.scrollTop() + $window.height() - this.$control.height() - this.controlattrs.offsety

		this.$control.css({left:controlx+'px', top:controly+'px'})

	},
	
	clear:function(){
		var ele = document.getElementById("topcontrol")
		ele.parentNode.removeChild(ele);
		window.scrollTo(0,0);
	},
	togglecontrol:function(){
	var scrolltop=jQuery(window).scrollTop()
	if (!this.cssfixedsupport)
		this.keepfixed()
		this.state.shouldvisible=(scrolltop>=this.setting.startline)? true : false
		if (this.state.shouldvisible && !this.state.isvisible){
			this.$control.stop().animate({opacity:1}, this.setting.fadeduration[0])
			this.state.isvisible=true
		}
		else if (this.state.shouldvisible==false && this.state.isvisible){
			this.$control.stop().animate({opacity:0}, this.setting.fadeduration[1])
			this.state.isvisible=false
		}
	},
	
	init:function(){
		jQuery(document).ready(function($){
			var mainobj=scrolltotop
			var iebrws=document.all
			
			var $window=jQuery(window)
			
			var w=document.getElementById("content").offsetWidth;

			 var tempval=0;
			 
			 sReso=screen.width;

			 if(window.innerWidth < sReso) {
			 	tempval= window.innerWidth ;

			 }
			 else
     		  tempval = window.innerWidth * 0.25;

			var windowwidth = window.innerWidth?window.innerWidth:document.documentElement.clientWidth;

			  tempval = windowwidth/2+w/2;
			  if(tempval<w)
			  	tempval = w+10;

			 mainobj.controlattrs.offsetx=tempval+25

			
			mainobj.cssfixedsupport=!iebrws || iebrws && document.compatMode=="CSS1Compat" && window.XMLHttpRequest //not IE or IE7+ browsers in standards mode
			mainobj.$body=$('html,body')
			mainobj.$control=$('<div id="topcontrol">'+mainobj.controlHTML+'</div>')
				.css({position:mainobj.cssfixedsupport? 'fixed' : 'absolute', bottom:mainobj.controlattrs.offsety+105, left:mainobj.controlattrs.offsetx, opacity:0, cursor:'pointer'})
				.attr({title:'Scroll Back to Top'})
				.click(function(){mainobj.scrollup(); return false})
				.appendTo('body')
			if (document.all && !window.XMLHttpRequest && mainobj.$control.text()!='') //loose check for IE6 and below, plus whether control contains any text
				mainobj.$control.css({width:mainobj.$control.width()}) //IE6- seems to require an explicit width on a DIV containing text
			mainobj.togglecontrol()
			$('a[href="' + mainobj.anchorkeyword +'"]').click(function(){
				mainobj.scrollup()
				return false
			})
			$(window).bind('scroll resize', function(e){
				mainobj.togglecontrol()
			})
		})
	}
}

scrolltotop.init();