// the following code is a slightly mangled moo.fx (http://moofx.mad4milk.net)
// by valerio proietti (http://mad4milk.net)
// 10/24/2005 v(1.0.2) under mit-style license
var fx = {}
fx.Base = function(){}
fx.Base.prototype = {
	setOptions: function(options) {
		this.options = { duration: 500, onComplete: '' }
		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 = extend(new fx.Base(), {
	initialize: function(el, options) {
		this.el = $id(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()
extend(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()
extend(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 = extend(new fx.Base(), {
	initialize: function(el, options) {
		this.el = $id(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)
	}
})

//composition effect, calls Opacity and (Width and/or Height) alltogether
fx.FadeSize = Class.create()
fx.FadeSize.prototype = {
	initialize: function(el, options) {
		this.el = $id(el)
		this.el.o = new fx.Opacity(el, options)
		if (options) options.onComplete = null
		this.el.h = new fx.Height(el, options)
		this.el.w = new fx.Width(el, options)
	},
	toggle: function() {
		this.el.o.toggle()
		for (var i = 0; i < arguments.length; i++) {
			if (arguments[i] == 'height') this.el.h.toggle()
			if (arguments[i] == 'width') this.el.w.toggle()
		}
	},
	hide: function(){
		this.el.o.hide()
		for (var i = 0; i < arguments.length; i++) {
			if (arguments[i] == 'height') this.el.h.hide()
			if (arguments[i] == 'width') this.el.w.hide()
}}}