/*
* 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);
  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 : 5,
 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);
}