/****************************************************************************
 * moo.fx, simple effects library built with prototype.js (http://prototype.conio.net).
 * by Valerio Proietti (http://mad4milk.net) MIT-style LICENSE.
 * for more info (http://moofx.mad4milk.net).
 * Sunday, March 05, 2006
 * v 1.2.3
 ****************************************************************************
 * edited by Simone Cingano
 ****************************************************************************
 * @version         SVN: $Id: moo.fx.js 8 2008-05-22 00:26:46Z imente $
 ****************************************************************************/

var fx = new Object();
//base
fx.Base = function(){};
fx.Base.prototype = {
	setOptions: function(options) {
	this.options = {
		duration: 500,
		onComplete: '',
		transition: fx.sinoidal
	}
	Object.extend(this.options, options || {});
	},

	step: function() {
		var time  = (new Date).getTime();
		if (time >= this.options.duration+this.startTime) {
			this.now = this.to;
			clearInterval (this.timer);
			this.timer = null;
			if (this.options.onComplete) setTimeout(this.options.onComplete.bind(this), 10);
		}
		else {
			var Tpos = (time - this.startTime) / (this.options.duration);
			this.now = this.options.transition(Tpos) * (this.to-this.from) + this.from;
		}
		this.increase();
	},

	custom: function(from, to) {
		if (this.timer != null) return;
		this.from = from;
		this.to = to;
		this.startTime = (new Date).getTime();
		this.timer = setInterval (this.step.bind(this), 13);
	},

	hide: function() {
		this.now = 0;
		this.increase();
	},

	clearTimer: function() {
		clearInterval(this.timer);
		this.timer = null;
	}
}

//stretchers
fx.Layout = Class.create();
fx.Layout.prototype = Object.extend(new fx.Base(), {
	initialize: function(el, options) {
		this.el = $(el);
		this.el.style.overflow = "hidden";
		this.iniWidth = this.el.offsetWidth;
		this.iniHeight = this.el.offsetHeight;
		this.setOptions(options);
	}
});

fx.Height = Class.create();
Object.extend(Object.extend(fx.Height.prototype, fx.Layout.prototype), {	
	increase: function() {
		this.el.style.height = this.now + "px";
	},

	toggle: function() {
		if (this.el.offsetHeight > 0) this.custom(this.el.offsetHeight, 0);
		else this.custom(0, this.el.scrollHeight);
	}
});

fx.Width = Class.create();
Object.extend(Object.extend(fx.Width.prototype, fx.Layout.prototype), {	
	increase: function() {
		this.el.style.width = this.now + "px";
	},

	toggle: function(){
		if (this.el.offsetWidth > 0) this.custom(this.el.offsetWidth, 0);
		else this.custom(0, this.iniWidth);
	}
});

//fader
fx.Opacity = Class.create();
fx.Opacity.prototype = Object.extend(new fx.Base(), {
	//START added by Simone Cingano
	initialize: function(el, options, start) {
		this.el = $(el);
		this.now = start;
		this.increase();
		this.setOptions(options);
	},

	increase: function() {
		if (this.now == 1 && (/Firefox/.test(navigator.userAgent))) this.now = 0.9999;
		this.setOpacity(this.now);
	},
	
	setOpacity: function(opacity) {
		if (opacity == 0 && this.el.style.visibility != "hidden") this.el.style.visibility = "hidden";
		else if (this.el.style.visibility != "visible") this.el.style.visibility = "visible";
		if (window.ActiveXObject) this.el.style.filter = "alpha(opacity=" + opacity*100 + ")";
		this.el.style.opacity = opacity;
	},

	toggle: function() {
		if (this.now > 0) this.custom(1, 0);
		else this.custom(0, 1);
	}
});

//transitions
fx.sinoidal = function(pos){ return ((-Math.cos(pos*Math.PI)/2) + 0.5); }
fx.linear = function(pos){ return pos; }
fx.cubic = function(pos){ return Math.pow(pos, 3); }
fx.circ = function(pos){ return Math.sqrt(pos); }
fx.expoIn = function(pos){return Math.pow(2, 10 * (pos - 1))};
fx.expoOut = function(pos){return (-Math.pow(2, -10 * pos) + 1)};
fx.quadIn = function(pos){return Math.pow(pos, 2)};
fx.quadOut = function(pos){return -(pos)*(pos-2)};
fx.circOut = function(pos){return Math.sqrt(1 - Math.pow(pos-1,2))};
fx.circIn = function(pos){return -(Math.sqrt(1 - Math.pow(pos, 2)) - 1)};
fx.backIn = function(pos){return (pos)*pos*((2.7)*pos - 1.7)};
fx.backOut = function(pos){return ((pos-1)*(pos-1)*((2.7)*(pos-1) + 1.7) + 1)};
fx.sineOut = function(pos){return Math.sin(pos * (Math.PI/2))};
fx.sineIn = function(pos){return -Math.cos(pos * (Math.PI/2)) + 1};
fx.sineInOut = function(pos){return -(Math.cos(Math.PI*pos) - 1)/2};