Subfolders/Folders Issue

So I am trying to get a handle on getFiles and folder structure.

Currently I have a script that works fine, except it runs repetitively due to how I have my folder call setup. I'm uncertain how to get past it, because it has some functionality I need and frankly I'm new at using .js on folder structures.

So I have a target folder, tFolder, and within this, subfolders to run through the script. Within these folders are .psd files that have a count of 3-5 files.

Currently the script iterates through each file, however many files are in the subfolder, which of course isn't ideal. Could someone help with a modification of the script below? .pop seemed to be the right direction but I couldn't get it to work in this case.

try{
       var tFolder = Folder.selectDialog("Select the folder with PSDs to process");
        var mainFldr = tFolder.path;

}
catch(error){
    alert("User Cancelled Folder Selection")
    }   

try {
           if (tFolder != null)  processFolder(tFolder);

            function processFolder(folder) {
                var fileList = folder.getFiles()
                 for (var i = 0; i < fileList.length; i++) {

                        if (fileList instanceof File && fileList.name.match(/\.(psd)$/i)) {
                            fileOpen(fileList, i);
                                                }

////// This is the area  I know I need to rewrite, but I cannot figure out a way to modify this correctly//////////

                    else if (fileList instanceof Folder) {                       
                       
                   processFolder(fileList);


                        }
                    }
                }
  
   }
    catch(error){
        alert(String("Error in parent process \n"+error))
  
}