update main.js to create navButton

lib/main.js

@@ -1,43 +1,76 @@
+//Initialize everything we need
 var tabs = require("tabs");
 var windows = require("windows").browserWindows;
 var widgets = require("widget");
 var self = require("self");
 data = self.data;  
 var { MatchPattern } = require("match-pattern");
+var {Cc, Ci} = require("chrome");
+var mediator = Cc['@mozilla.org/appshell/window-mediator;1'].getService(Ci.nsIWindowMediator);
 
+//variable to store the script (string) to run when a button or widget is clicked
+var myScript;
 
 exports.main = function() {
+
+  //call the function down below to add a button to the navigation bar
+  addToolbarButton();
 
- var myScript;    
-
+  //when the tab is ready check the URL and store the proper value to myScript 
     tabs.on('ready', function(tab) {
        var tabURL = tab.url;
 
         var pattern = new MatchPattern(/.*youtube\.com\/watch.*/);
 
         var pattern2 = new MatchPattern(/.*&html5=1*/); 
 
+        //if URL is correct create myScript
         if ((pattern.test(tab.url)) && !(pattern2.test(tab.url)))  {        
             var stringarray = ["window.location.href=\"", tabURL, "&html5=1\"" ]
             myScript = stringarray.join('') ;       
-        }else{     
+        }else{
+        //if URL not correct do nothing
            myScript = null;
         }
     });
 
-
+//create a clickable widget that runs myScript
     var widget = widgets.Widget({
 
       id: "switch",
       label: "Switch player",
       contentURL: data.url("icon.html"),
-
-
+
           onClick: function() {
             tabs.activeTab.attach({
               contentScript: myScript
-            });
+            });                    
           }
 
     });
 };
+
+
+//function to create the button on the navigation bar
+function addToolbarButton() {
+    var document = mediator.getMostRecentWindow("navigator:browser").document;      
+    var navBar = document.getElementById("nav-bar");
+    if (!navBar) {
+        return;
+    }
+    var navButton = document.createElement("toolbarbutton");  
+
+    navButton.setAttribute('type', 'button');
+    navButton.setAttribute('class', 'toolbarbutton-1');
+    navButton.setAttribute('image', data.url('yhs.ico'));
+    navButton.setAttribute('orient', 'horizontal');
+    navButton.setAttribute('label', 'YouTube HTML Switch');
+    navButton.addEventListener('click', function() {
+     tabs.activeTab.attach({
+              contentScript: myScript
+            });      
+    }, false)
+    navBar.appendChild(btn);
+}
+
+