fix #728 check if thumbExtractor is supported

remove fileReader its not needed

fix unit tests

fix typo

remove unecessary message

www/prod/ThumbExtractor.js

@@ -1,30 +1,30 @@
 ;
 (function(document){
-  
+
   /*****************
    * Canva Object
    *****************/
   var Canva = function(domCanva){
     this.domCanva = domCanva;
   }
-  
+
   Canva.prototype = {
     resize : function(elementDomNode){
       var h = elementDomNode.getHeight();
       var w = elementDomNode.getWidth();
-      
+
       this.domCanva.setAttribute("width", w);
       this.domCanva.setAttribute("height", h);
-      
+
       return this;
     },
     getContext2d : function(){
 
-      if (this.domCanva.getContext == undefined) 
+      if (this.domCanva.getContext == undefined)
       {
         return G_vmlCanvasManager
         .initElement(this.domCanva)
-        .getContext("2d"); 
+        .getContext("2d");
       }
 
       return this.domCanva.getContext('2d');
@@ -36,17 +36,17 @@
       var context = this.getContext2d();
       var w = this.getWidth();
       var h =  this.getHeight();
-      
+
       context.save();
       context.setTransform(1, 0, 0, 1, 0, 0);
       context.clearRect(0, 0, w, h);
       context.restore();
-        
+
       return this;
     },
     copy : function(elementDomNode){
       var context = this.getContext2d();
-      
+
       context.drawImage(
         elementDomNode.getDomElement()
         , 0
@@ -54,7 +54,7 @@
         , this.getWidth()
         , this.getHeight()
         );
-            
+
       return this;
     },
     getDomElement : function(){
@@ -67,15 +67,15 @@
       return this.domCanva.offsetWidth;
     }
   };
-  
-      
+
+
   /******************
  *  Image Object
  ******************/
   var Image = function(domElement){
     this.domElement = domElement;
   };
-  
+
   Image.prototype = {
     getDomElement : function(){
       return this.domElement;
@@ -87,28 +87,28 @@
       return this.domElement.offsetWidth;
     }
   };
-  
+
   /******************
  *  Video Object inherits from Image object
  ******************/
-  
+
   var Video = function(domElement){
     Image.call(this, domElement);
   };
-  
+
   Video.prototype = new Image();
   Video.prototype.constructor = Video;
   Video.prototype.getCurrentTime = function(){
     return Math.floor(this.domElement.currentTime);
   };
-  
+
   /******************
  *  Cache Object
  ******************/
   var Store = function(){
     this.datas = {};
   };
-  
+
   Store.prototype = {
     set : function(id, item){
       this.datas[id] = item;
@@ -133,23 +133,23 @@
       return count;
     }
   };
-  
+
   /******************
  *  Screenshot Object
  ******************/
   var ScreenShot = function(id, canva, video){
-    
+
     var date = new Date();
-    
+
     canva.resize(video);
     canva.copy(video);
-    
+
     this.id = id;
     this.timestamp = date.getTime();
     this.dataURI = canva.extractImage();
     this.videoTime = video.getCurrentTime();
   }
-  
+
   ScreenShot.prototype = {
     getId:function(){
       return this.id;
@@ -164,29 +164,34 @@
       return this.videoTime;
     }
   };
-    
+
   /**
  * THUMB EDITOR
  */
   var ThumbEditor = function(videoId, canvaId){
-    
+
     var editorVideo = new Video(document.getElementById(videoId));
     var store = new Store();
-    
+
     function getCanva(){
       return document.getElementById(canvaId);
     }
-    
+
     return {
+      isSupported : function () {
+          var elem = document.createElement('canvas');
+
+          return !! elem.getContext && !! elem.getContext('2d');
+      },
       screenshot : function(){
         var screenshot = new ScreenShot(
           store.getLength() + 1,
           new Canva(getCanva()),
           editorVideo
           );
-        
+
         store.set(screenshot.getId(), screenshot);
-        
+
         return screenshot;
       },
       store : store,
@@ -213,6 +218,6 @@
   };
 
   document.THUMB_EDITOR = ThumbEditor;
-  
+
 })(document);