/*
* Crossfade
* Version 4.1 30/03/2007
* 
* Copyright (c) 2007 Millstream Web Software http://www.millstream.com.au
* 
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* 
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
* * 
*/

var Crossfade = Class.create();

Crossfade.prototype = {
	loaded : false,
	initialize : function(elm, options) {
		var me = this, next, prev;
		this.elm = $(elm);
		this.counter = 0;
		this.prevSlide = null;
		var t_opt = {};
		for(t in Crossfade.Transition) {
			var trans = Crossfade.Transition[t];
			if(trans.className && this.elm.hasClassName(trans.className)) {
				t_opt = {transition:trans};
				break;
			}
		}
		this.options = Object.extend(Object.clone(Crossfade.defaults),Object.extend(options || {},t_opt));
		this.options.interval = Math.max(2,this.options.interval);
		this.elm.makePositioned();
		this.slides = this.elm.immediateDescendants();
		if(this.options.random || this.elm.hasClassName(this.options.randomClassName)){
			this.slides.sort(function(a,b){
				return me.rndm(-1,1);
			});
		}
		if(this.elm.id) {
			next = $(this.elm.id + '-next');
			prev = $(this.elm.id + '-previous');
			if(next) { Event.observe(next, 'click', this.next.bind(this)); }
			if(prev) { Event.observe(prev, 'click', this.previous.bind(this)); }
		}
		
		this.loadSlide(this.slides[0],function() {
			me.options.transition.prepare(me);
		});
		this.loadSlide(this.slides[1]);
		
		if(this.options.autoStart) { setTimeout(this.start.bind(this),this.rndm((this.options.interval-1)*1000,(this.options.interval+1)*1000)); }
	},
	start : function() {
		this.ready = true;
		this.cycle()
		return this.timer = new PeriodicalExecuter(this.cycle.bind(this), this.options.interval); 
	},
	stop : function() {
		this.options.transition.cancel(this);
		if(this.timer) this.timer.stop(); 
	},
	next : function(){
		this.options.transition.cancel(this);
		this.cycle();
	},
	previous : function() {
		this.options.transition.cancel(this);
		this.cycle(-1);
	},
	cycle : function(dir) {
		if(!this.ready) { return; }
		this.ready = false;
		dir = (dir === -1) ? dir : 1;
		var me = this, prevSlide, nextSlide, opt, fade;
		prevSlide = this.slides[this.counter];
		this.counter = this.loopCount(this.counter + dir);
		if(this.counter == 0){
			this.loaded = true;
		}
		nextSlide = this.slides[this.counter];
		this.loadSlide(nextSlide, me.options.transition.cycle(prevSlide, nextSlide, me));
		if(!this.loaded) {
			this.loadSlide(this.slides[this.loopCount(this.counter+1)]);
		}
	},
	loadSlide : function(slide, onload){
		var loaders = [], me = this, img, pnode, onloadFunction;
		onload = typeof onload === 'function' ? onload : function(){};
		onloadFunction = function() {
				onload();
				me.ready = true;
			};
		slide = $(slide);
		loaders = Selector.findChildElements(slide,[this.options.imageLoadSelector]);
		if(loaders.length && loaders[0].href !== ''){
			img = document.createElement('img');
			img.className = 'loadimage';
			img.onload = onloadFunction;
			img.src = loaders[0].href;
			loaders[0].parentNode.replaceChild(img,loaders[0]);
		} else {
			loaders = [];
			loaders = Selector.findChildElements(slide, [this.options.ajaxLoadSelector]);
			if(loaders.length && loaders[0].href !== ''){
				new Ajax.Updater(slide, loaders[0].href, {method:'get',onComplete:onloadFunction});
			} else {
				onloadFunction();
			}
		}
	},
	loopCount : function(c){
		if(c >= this.slides.length){
			c = 0;
		} else if (c < 0) {
			c = this.slides.length - 1
		}
		return c;
	},
	rndm : function(min, max){
		return Math.floor(Math.random() * (max - min + 1) + min);
	},
	timer : null,effect : null,ready : false
};
Crossfade.Transition = {};
Crossfade.Transition.Switch = {
	className : 'transition-switch',
	cycle : function(prev, next, show) {
		show.slides.without(next).each(function(s){
			$(s).hide();
		})
		$(next).show();
	},
	cancel : function(show){},
	prepare : function(show){
		show.slides.each(function(s,i){
			$(s).setStyle({display:(i === 0 ? 'block' : 'none')});
		});	
	}
};
Crossfade.Transition.Crossfade = {
	className : 'transition-crossfade',
	cycle : function(prev, next, show) {
		var opt = show.options;
		show.effect = new Effect.Parallel([new Effect.Fade(prev ,{sync:true}),
			new Effect.Appear(next,{sync:true})],
			{duration: opt.duration, queue : 'Crossfade', afterFinish:function(){
				show.slides.without(next).each(function(s){
					$(s).setStyle({opacity:0});
				})
			}}
		);
	},
	cancel : function(show){
		if(show.effect) { show.effect.cancel(); }
	},
	prepare : function(show){
		show.slides.each(function(s,i){
			$(s).setStyle({opacity:(i === 0 ? 1 : 0),visibility:'visible'});
		});	
	}
};
Crossfade.Transition.FadeOutFadeIn = {
	className : 'transition-fadeoutfadein',
	cycle : function(prev, next, show) {
		var opt = show.options;
		show.effect = new Effect.Fade(prev ,{
			duration: opt.duration/2,
			afterFinish: function(){
				show.effect = new Effect.Appear(next,{duration: opt.duration/2});
				show.slides.without(next).each(function(s){
					$(s).setStyle({opacity:0});
				})
			}
		});
	},
	cancel : function(show){
		if(show.effect) { show.effect.cancel(); }
	},
	prepare : function(show){
		show.slides.each(function(s,i){
			$(s).setStyle({opacity:(i === 0 ? 1 : 0),visibility:'visible'});
		});	
	}
};

Effect.DoNothing = Class.create();
Object.extend(Object.extend(Effect.DoNothing.prototype, Effect.Base.prototype), {
	initialize: function() {
		this.start({duration: 0});
	},
	update: Prototype.emptyFunction
});
Crossfade.Transition.FadeOutResizeFadeIn = {
	className : 'transition-fadeoutresizefadein',
	cycle : function(prev, next, show) {
		var opt = show.options;
		show.effect = new Effect.Fade(prev ,{
			duration: (opt.duration-1)/2,
			afterFinish: function(){
				show.slides.without(next).each(function(s){
					$(s).setStyle({opacity:0});
				})
				var slideDims = [next.getWidth(),next.getHeight()];
				var loadimg = Selector.findChildElements(next,['img.loadimage']);
				if(loadimg.length && loadimg[0].offsetWidth && loadimg[0].offsetHeight){
					slideDims[0] += slideDims[0] < loadimg[0].offsetWidth ? loadimg[0].offsetWidth : 0;
					slideDims[1] += slideDims[1] < loadimg[0].offsetHeight ? loadimg[0].offsetHeight : 0;
				}
				var showDims = [show.elm.getWidth(),show.elm.getHeight()];
				var scale = [(showDims[0] > 0 && slideDims[0] > 0 ? slideDims[0]/showDims[0] : 1)*100,(showDims[1] > 0 && slideDims[1] > 0 ? slideDims[1]/showDims[1] : 1)*100];
				show.effect = new Effect.Parallel([
						(scale[0] === 100 ? new Effect.DoNothing() : new Effect.Scale(show.elm,scale[0],{sync:true,scaleY:false,scaleContent:false})),
						(scale[1] === 100 ? new Effect.DoNothing() : new Effect.Scale(show.elm,scale[1],{sync:true,scaleX:false,scaleContent:false}))
					],
					{
						duration: 1,
						queue : 'FadeOutResizeFadeIn',
						afterFinish: function(){
							show.effect = new Effect.Appear(next,{duration: (opt.duration-1)/2});
						}
					}
				);
			}
		});
	},
	cancel : function(show){
		if(show.effect) { show.effect.cancel(); }
	},
	prepare : function(show){
		var slideDims = [$(show.slides[0]).getWidth(),$(show.slides[0]).getHeight()];
		show.elm.setStyle({width:slideDims[0]+'px', height:slideDims[1]+'px'});
		show.slides.each(function(s,i){
			$(s).setStyle({opacity:(i === 0 ? 1 : 0),visibility:'visible'});
		});	
	}
};
Crossfade.defaults = {
	autoLoad : true,
	autoStart : true,
	random : false,
	randomClassName : 'random',
	selectors : ['.crossfade'],
	imageLoadSelector : 'a.loadimage',
	ajaxLoadSelector : 'a.load',
	interval : 3,
	duration : 2,
	transition : Crossfade.Transition.Crossfade
};
Crossfade.setup = function(options) {
	Object.extend(Crossfade.defaults,options);
};
Crossfade.load = function() {
	if(Crossfade.defaults.autoLoad) {
		Crossfade.defaults.selectors.each(function(s){
			$$(s).each(function(c){
				return new Crossfade(c);
			});
		});
	}
};

if(window.FastInit) {
	FastInit.addOnLoad(Crossfade.load);
} else {
	Event.observe(window, 'load', Crossfade.load);
}