var Scroll = Class.create();



Effect.Transitions.easeOutExpo = function(pos) {
	return(pos==1) ? 1 : 1.001 *(-Math.pow(2, -10 * pos) + 1);
	//return -pos*(pos-2)+pos*+2*pos;
	//return -c *(t/=d)*(t-2) + b;
}


Scroll.prototype = {
    initialize: function(_scrollClassName,parentElement) {
		var ScrollObj = document.getElementsByClassName(_scrollClassName, parentElement);
		//alert(parentElement);
        for (var i = 0, len = ScrollObj.length; i < len; i++) {
			//alert(ScrollObj[i]);
        	Event.observe(ScrollObj[i], 'click', this.addScrollEvent.bindAsEventListener(this));
        	Event.observe(ScrollObj[i], 'keypress', this.addScrollEvent.bindAsEventListener(this));
		}
    },
    addScrollEvent: function(event) {
        var ScrollElement = Event.element(event);
		new Effect.ScrollTo(ScrollElement.hash.substr(1),{offset:0, duration:0.8,transition: Effect.Transitions.easeOutExpo});
        Event.stop(event);
    }
}


Event.observe(window, 'load', function () {
    new Scroll('pageTop','wrapper');
})