//base

var fx = new Object();

fx.Base = function(){};

fx.Base.prototype = {

	setOptions: function(options) {

	this.options = {

		duration: 500,
		onComplete: ''

	}

	Object.extend(this.options, options || {});

	},



	go: function() {

		this.duration = this.options.duration;

		this.startTime = (new Date).getTime();

		this.timer = setInterval (this.step.bind(this), 13);

	},



	step: function() {

		var time  = (new Date).getTime();

		var Tpos   = (time - this.startTime) / (this.duration);

		if (time >= this.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 {

			this.now = ((-Math.cos(Tpos*Math.PI)/2) + 0.5) * (this.to-this.from) + this.from;

			//this time-position, sinoidal transition thing is from script.aculo.us

		}

		this.increase();

	},



	custom: function(from, to) {

		if (this.timer != null) return;

		this.from = from;

		this.to = to;

		this.go();

	},



	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.el.iniWidth = this.el.offsetWidth;

		this.el.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.el.iniWidth);

	}

});



//fader

fx.Opacity = Class.create();

fx.Opacity.prototype = Object.extend(new fx.Base(), {

	initialize: function(el, options) {

		this.el = $(el);

		this.now = 1;

		this.increase();

		this.setOptions(options);

	},



	increase: function() {

		if (this.now == 1) this.now = 0.9999;

		if (this.now > 0 && this.el.style.visibility == "hidden") this.el.style.visibility = "visible";

		if (this.now == 0) this.el.style.visibility = "hidden";

		if (window.ActiveXObject) this.el.style.filter = "alpha(opacity=" + this.now*100 + ")";

		this.el.style.opacity = this.now;

	},



	toggle: function() {

		if (this.now > 0) this.custom(1, 0);

		else this.custom(0, 1);

	}

});