var coolScroll = {
	
	init: function() {
		var scrollLinks = YAHOO.util.Dom.getElementsByClassName('subNav');
		YAHOO.util.Event.addListener(scrollLinks, 'click', coolScroll.doScroll);
		YAHOO.util.Event.addListener(window, 'scroll', coolScroll.proxyScroll);
		YAHOO.util.Event.addListener('proxyEl', 'click', coolScroll.scrollToTop);

		coolScroll.proxyEl = document.getElementById('proxyEl');
		YAHOO.util.Dom.setStyle(coolScroll.proxyEl, 'opacity' ,0);
	},
	
	scrollToTop: function(e) {
		YAHOO.util.Event.preventDefault(e);
		var attr = { top: { to: 0 } };
		anim = new YAHOO.util.Anim(coolScroll.proxyEl, attr, 1, YAHOO.util.Easing.easeOut);
		anim.onTween.subscribe(coolScroll.getProxyCoord);
		anim.animate();	
	},
	
	doScroll: function(e) {
		YAHOO.util.Event.preventDefault(e);
		var targetAnchor = this.id.split('-')[1];
		//targetAnchor += '_' + this.id.split('_')[2];
		
		var newY = YAHOO.util.Dom.getY(targetAnchor);
		var startY = coolScroll.yScrollAmount();
		
		var attr = {
			top: { from: startY, to: newY }
		};
		
		anim = new YAHOO.util.Anim(coolScroll.proxyEl, attr, 1, YAHOO.util.Easing.easeOut);
		anim.onTween.subscribe(coolScroll.getProxyCoord);
		anim.animate();
	},
	
	proxyScroll: function() {
		var scAmount = coolScroll.yScrollAmount();
		YAHOO.util.Dom.setY(coolScroll.proxyEl, scAmount);
		
		if ( scAmount < 200 ) YAHOO.util.Dom.setStyle(coolScroll.proxyEl, 'opacity' ,0);
		else YAHOO.util.Dom.setStyle(coolScroll.proxyEl, 'opacity' ,100);
		
	},
	
	getProxyCoord: function() {
		var coord = YAHOO.util.Dom.getY(coolScroll.proxyEl);
		coolScroll.scrollPage(0, coord); 
	},
	
	yScrollAmount: function() {
		var yScroll = (window.pageYOffset)?(window.pageYOffset):(document.documentElement)?document.documentElement.scrollTop:document.body.scrollTop;
		return yScroll
	},
	
	scrollPage: function(x, y) {
		window.scroll(x, y);
	},
	
	trace: function(str) {
		document.getElementById('trace').innerHTML = str;		
	},
	
	traceScroll: function() {
		var y_scroll_amount = (window.pageYOffset)?(window.pageYOffset):(document.documentElement)?document.documentElement.scrollTop:document.body.scrollTop;
		var x_scroll_amount = (window.pageXOffset)?(window.pageXOffset):(document.documentElement)?document.documentElement.scrollLeft:document.body.scrollLeft;	
	}
	
	
};


YAHOO.util.Event.addListener(window, 'load', coolScroll.init);