source: Dev/trunk/src/client/dojox/av/FLAudio.js

define(['dojo', 'dojox/embed/Flash', 'dojox/timing/doLater'],function(dojo, dijit){

dojo.experimental("dojox.av.FLVideo");

return dojo.declare("dojox.av.FLAudio", null, {

        // summary:
        //              Play MP3 files through the Flash SWF built in the
        //              DEFT project.
        // description:
        //              This class is brand new, so there is a lot of
        //              functionality not yet available. The initial
        //              purpose is for playing "event" sounds like button
        //              clicks, and for loading and controlling multiple
        //              sounds at once. As of yet, streaming is not supported
        //              and polling the sounds for events during playback
        //              may still be missing information. Markup is not
        //              supported, as it may not be needed.
        //
        //              TODO:
        //              Streaming, playback events, crossdomain, CDN support,
        //              (alternate SWF location), global volume, ID3 tag,
        //              factor out doLater, onLoadStatus needs work,
        //              play(position) / seek()
        //
        // example:
        //              |       new dojox.av.FLAudio({
        //              |               initialVolume:.7,
        //              |               initialPan:0,
        //              |               autoPlay:false
        //              |       });

        // id: String?
        //              The id of this widget and the id of the SWF movie.
        id:"",

        // initialVolume: Number
        //              From 0-1
        //              Sets volume for all files unless changed with doPlay
        //              or setVolume
        initialVolume: 0.7,

        // initialPan: Number
        //              From -1 to 1 (-1 is left, 1 is right, 0 is middle)
        //              Sets pan for all files unless changed with play
        //              or setPan
        initialPan: 0,

        // autoPlay: Boolean
        //              If true, all files will play upon load. If false,
        //              they load and wait for doPlay() command.

        // isDebug: Boolean?
        //              Setting to true tells the SWF to output log messages to Firebug.
        isDebug: false,

        // statusInterval: Number
        //              How often in milliseconds that the status of the
        //              player is checked - both load and play
        statusInterval:200,

        // _swfPath: Uri
        //              The path to the video player SWF resource
        _swfPath: dojo.moduleUrl("dojox.av", "resources/audio.swf"),

        // allowScriptAccess: String
        //              Whether the SWF can access the container JS
        allowScriptAccess:"always",

        // allowNetworking: String
        //              Whether SWF is restricted to a domain
        allowNetworking: "all",

        constructor: function(/*Object*/options){

                // Provide this function for the SWF to ensure that the it is playing
                // in HTML.
                dojo.global.swfIsInHTML = function(){ return true; }

                dojo.mixin(this, options || {});
                if(!this.id){ this.id = "flaudio_"+new Date().getTime(); }
                this.domNode = dojo.doc.createElement("div");
                dojo.style(this.domNode, {
                        position:"relative",
                        width:"1px",
                        height:"1px",
                        top:"1px",
                        left:"1px"
                });
                dojo.body().appendChild(this.domNode);
                this.init();
        },

        init: function(){
                // summary:
                //              Initialize the media.

                this._subs = [];
                this.initialVolume = this._normalizeVolume(this.initialVolume);

                var args = {
                        path:this._swfPath,
                        width:"1px",
                        height:"1px",
                        minimumVersion:9, // this may need to be 10, not sure
                        expressInstall:true,
                        params:{
                                wmode:"transparent",
                                allowScriptAccess:this.allowScriptAccess,
                                allowNetworking:this.allowNetworking
                        },
                        // only pass in simple variables - no deep objects
                        vars:{
                                id:this.id,
                                autoPlay:this.autoPlay,
                                initialVolume:this.initialVolume,
                                initialPan:this.initialPan,
                                statusInterval:this.statusInterval,
                                isDebug:this.isDebug
                        }
                };

                this._sub("mediaError",    "onError");
                this._sub("filesProgress", "onLoadStatus");
                this._sub("filesAllLoaded", "onAllLoaded");
                this._sub("mediaPosition", "onPlayStatus");
                this._sub("mediaEnd", "onComplete");
                this._sub("mediaMeta",     "onID3");

                this._flashObject = new dojox.embed.Flash(args, this.domNode);
                this._flashObject.onError = function(err){
                        console.warn("Flash Error:", err);
                };
                this._flashObject.onLoad = dojo.hitch(this, function(mov){
                        this.flashMedia = mov;
                        this.isPlaying = this.autoPlay;
                        this.isStopped = !this.autoPlay;
                        this.onLoad(this.flashMedia);
                });
        },

        //  ==============  //
        //  Loading Files   //
        //  ==============  //

        load: function(/*Object*/options){
                // summary:
                //              Adds a media object to the playlist
                //              ***This can be called repeatedly to add multiple items.
                // options: Object
                //              - url: String:
                //                      (required) path to MP3 media
                //                      url must be absolute or relative to SWF,
                //                      not dojo or the html. An effort will be made
                //                      to fix incorrect paths.
                //              - id: String:
                //                      (optional) an identifier to later determine
                //                      which media to control.
                // returns:
                //              The normalized url, which can be used to identify the
                //              audio.

                if(dojox.timing.doLater(this.flashMedia, this)){ return false; }
                if(!options.url){
                        throw new Error("An url is required for loading media");
                }else{
                        options.url = this._normalizeUrl(options.url);
                }
                this.flashMedia.load(options);

                return options.url; // String
        },

        //  =============================  //
        //  Methods to control the sound   //
        //  =============================  //

        doPlay: function(/*Object*/options){
                // summary:
                //              Tell media to play, based on
                //              the options passed.
                // options: Object
                //              - volume: Number:
                //                      Sets the volume
                //              - pan: Number:
                //                      Sets left/right pan
                //              - index:Number OR id:String OR url:String:
                //                      Choose one of the above to identify
                //                      the media you wish to control. id is
                //                      set by you. index is the order in which
                //                      media was added (zero based)
                //                      NOTE: lack of an identifier will default
                //                      to first (or only) item.

                //      NOTE: Can't name this method "play()" as it causes
                //                      an IE error.
                this.flashMedia.doPlay(options);
        },

        pause: function(/*Object*/options){
                // summary:
                //              Tell media to pause, based on identifier in
                //              the options passed.
                // options: Object
                //              index:Number OR id:String OR url:String.
                //              See doPlay().

                this.flashMedia.pause(options);
        },

        stop: function(/*Object*/options){
                // summary:
                //              Tell media to stop, based on identifier in
                //              the options passed.
                // options:
                //              index:Number OR id:String OR url:String.
                //              See doPlay().

                this.flashMedia.doStop(options);
        },

        setVolume: function(/*Object*/options){
                // summary:
                //              Set media volume, based on identifier in
                //              the options passed.
                // options:
                //              volume: Number
                //              0 to 1
                //              index:Number OR id:String OR url:String.
                //              See doPlay().

                this.flashMedia.setVolume(options);
        },

        setPan: function(/*Object*/options){
                // summary:
                //              Set media pan, based on identifier in
                //              the options passed.
                // options:
                //              - pan:Number (from -1 to 1)
                //              - index:Number OR id:String OR url:String (see doPlay())

                this.flashMedia.setPan(options);
        },

        getVolume: function(/*Object*/options){
                // summary:
                //              Get media volume, based on identifier in
                //              the options passed.
                // options:
                //              index:Number OR id:String OR url:String.
                //              See doPlay().

                return this.flashMedia.getVolume(options);
        },

        getPan: function(/*Object*/options){
                // summary:
                //              Set media pan, based on identifier in
                //              the options passed.
                // options:
                //              index:Number OR id:String OR url:String.
                //              See doPlay().

                return this.flashMedia.getPan(options);
        },

        getPosition: function(/*Object*/options){
                // summary:
                //              Get the current time.
                // options:
                //              index:Number OR id:String OR url:String.
                //              See doPlay().

                return this.flashMedia.getPosition(options);
        },

        //  =============  //
        //  Sound Events   //
        //  =============  //
        onError: function(msg){
                // summary:
                //              stub fired when an error occurs
                console.warn("SWF ERROR:", msg)
        },

        onLoadStatus: function(/*Array*/events){
                // summary:
        },

        onAllLoaded: function(){
                // summary:
                //              stub fired
        },

        onPlayStatus: function(/*Array*/events){
                // summary:
        },

        onComplete: function(/*Array*/events){
                // summary:
                //              Fired at the end of a media file.
        },

        onLoad: function(){
                // summary:
                //              stub fired when SWF is ready
        },
        onID3: function(evt){
                // summary:
                //              Fired when the ID3 data is received.
        },



        destroy: function(){
                // summary:
                //              destroys flash
                if(!this.flashMedia){
                        this._cons.push(dojo.connect(this, "onLoad", this, "destroy"));
                        return;
                }
                dojo.forEach(this._subs, function(s){
                        dojo.unsubscribe(s);
                });
                dojo.forEach(this._cons, function(c){
                        dojo.disconnect(c);
                });
                this._flashObject.destroy();
                //dojo._destroyElement(this.flashDiv);
        },



        _sub: function(topic, method){
                // summary:
                //              helper for subscribing to topics
                dojo.subscribe(this.id+"/"+topic, this, method);
        },

        _normalizeVolume: function(vol){
                // summary:
                //              Ensures volume is less than one
                //
                if(vol>1){
                        while(vol>1){
                                vol*=.1
                        }
                }
                return vol;
        },

        _normalizeUrl: function(_url){
                // summary:
                //              Checks that path is relative to HTML file or
                //              converts it to an absolute path.

                if(_url && _url.toLowerCase().indexOf("http")<0){
                        //
                        // Appears to be a relative path. Attempt to  convert it to absolute,
                        // so it will better target the SWF.
                        var loc = window.location.href.split("/");
                        loc.pop();
                        loc = loc.join("/")+"/";

                        _url = loc+_url;
                }
                return _url;
        }

});

});