jsx photoshop to save every png file in subfolders as jpg

PS jsx script

var traverseFolder = function(path)  
{  
     // Create new folder object based on path string  
     var folder = new Folder(path);  
  
     // Get all files in the current folder  
     var files = folder.getFiles();  
  
     // Loop over the files in the files object  
     for (var i = 0; i < files.length; i++)  
     {  
          // Check if the file is an instance of a file  
          // else call the traverse folder recursively with the current folder as an argument  
          if (files[i] instanceof File)  
          {   
               // Convert the file object to a string for matching purposes (match only works on String objects)  
               var fileString = String(files[i]); 
  
               // Check if the file contains the right extension  
               if (fileString.match(/.(png)$/))
               {  
                    // Do something if the file matches 

                    var fileRef = new File(fileString);
                    var docRef = app.open (fileRef);
                    var Name = fileString.replace(/\.png$/, '.jpg');
                    var saveFile = File(Name);
                    SaveForWeb(saveFile,60);
                    app.activeDocument.close(SaveOptions.DONOTSAVECHANGES);

                    
               }  
               else  
               {  
                    // Do something if the file doesn't match  
                    alert(fileString + ' bad file');
               }  
          }  
          else  
          {  
               alert('passing folder: ' + files[i]);  
  
               // Call method recursively with the current folder as an argument  
               traverseFolder(files[i]);
          }  
     }  
}  
  
traverseFolder('~/desktop/ggg');

function SaveForWeb(saveFile,jpegQuality) {  
var sfwOptions = new ExportOptionsSaveForWeb();   
   sfwOptions.format = SaveDocumentType.JPEG;   
   sfwOptions.includeProfile = false;   
   sfwOptions.interlaced = 0;   
   sfwOptions.optimized = true;   
   sfwOptions.quality = jpegQuality;
activeDocument.exportDocument(saveFile, ExportType.SAVEFORWEB, sfwOptions);
}