/*
 Copyright (c) 2010, Yahoo! Inc. All rights reserved.
 Code licensed under the BSD License:
 http://developer.yahoo.com/yui/license.html
 version: 3.3.0
 build: 3167
 */
YUI.add('async-queue',function(Y){Y.AsyncQueue=function(){this._init();this.add.apply(this,arguments);};var Queue=Y.AsyncQueue,EXECUTE='execute',SHIFT='shift',PROMOTE='promote',REMOVE='remove',isObject=Y.Lang.isObject,isFunction=Y.Lang.isFunction;Queue.defaults=Y.mix({autoContinue:true,iterations:1,timeout:10,until:function(){this.iterations|=0;return this.iterations<=0;}},Y.config.queueDefaults||{});Y.extend(Queue,Y.EventTarget,{_running:false,_init:function(){Y.EventTarget.call(this,{emitFacade:true});this._q=[];this.defaults={};this._initEvents();},_initEvents:function(){this.publish({'execute':{defaultFn:this._defExecFn,emitFacade:true},'shift':{defaultFn:this._defShiftFn,emitFacade:true},'add':{defaultFn:this._defAddFn,emitFacade:true},'promote':{defaultFn:this._defPromoteFn,emitFacade:true},'remove':{defaultFn:this._defRemoveFn,emitFacade:true}});},next:function(){var callback;while(this._q.length){callback=this._q[0]=this._prepare(this._q[0]);if(callback&&callback.until()){this.fire(SHIFT,{callback:callback});callback=null;}else{break;}}
return callback||null;},_defShiftFn:function(e){if(this.indexOf(e.callback)===0){this._q.shift();}},_prepare:function(callback){if(isFunction(callback)&&callback._prepared){return callback;}
var config=Y.merge(Queue.defaults,{context:this,args:[],_prepared:true},this.defaults,(isFunction(callback)?{fn:callback}:callback)),wrapper=Y.bind(function(){if(!wrapper._running){wrapper.iterations--;}
if(isFunction(wrapper.fn)){wrapper.fn.apply(wrapper.context||Y,Y.Array(wrapper.args));}},this);return Y.mix(wrapper,config);},run:function(){var callback,cont=true;for(callback=this.next();cont&&callback&&!this.isRunning();callback=this.next())
{cont=(callback.timeout<0)?this._execute(callback):this._schedule(callback);}
if(!callback){this.fire('complete');}
return this;},_execute:function(callback){this._running=callback._running=true;callback.iterations--;this.fire(EXECUTE,{callback:callback});var cont=this._running&&callback.autoContinue;this._running=callback._running=false;return cont;},_schedule:function(callback){this._running=Y.later(callback.timeout,this,function(){if(this._execute(callback)){this.run();}});return false;},isRunning:function(){return!!this._running;},_defExecFn:function(e){e.callback();},add:function(){this.fire('add',{callbacks:Y.Array(arguments,0,true)});return this;},_defAddFn:function(e){var _q=this._q,added=[];Y.Array.each(e.callbacks,function(c){if(isObject(c)){_q.push(c);added.push(c);}});e.added=added;},pause:function(){if(isObject(this._running)){this._running.cancel();}
this._running=false;return this;},stop:function(){this._q=[];return this.pause();},indexOf:function(callback){var i=0,len=this._q.length,c;for(;i<len;++i){c=this._q[i];if(c===callback||c.id===callback){return i;}}
return-1;},getCallback:function(id){var i=this.indexOf(id);return(i>-1)?this._q[i]:null;},promote:function(callback){var payload={callback:callback},e;if(this.isRunning()){e=this.after(SHIFT,function(){this.fire(PROMOTE,payload);e.detach();},this);}else{this.fire(PROMOTE,payload);}
return this;},_defPromoteFn:function(e){var i=this.indexOf(e.callback),promoted=(i>-1)?this._q.splice(i,1)[0]:null;e.promoted=promoted;if(promoted){this._q.unshift(promoted);}},remove:function(callback){var payload={callback:callback},e;if(this.isRunning()){e=this.after(SHIFT,function(){this.fire(REMOVE,payload);e.detach();},this);}else{this.fire(REMOVE,payload);}
return this;},_defRemoveFn:function(e){var i=this.indexOf(e.callback);e.removed=(i>-1)?this._q.splice(i,1)[0]:null;},size:function(){if(!this.isRunning()){this.next();}
return this._q.length;}});},'3.3.0',{requires:['event-custom']});
