Custom Editor based on Page Template

Hey everyone, I’m trying to test something out based off of what I found on Smashing Magazine

They have enlightened me on a way to create multi-column layouts within the editor based on content types (post/page/custom). What I am trying to do is create a way for the columns to load in when the TEMPLATE (2-col/3-col) is selected.

I do NOT care about keeping content within the editor at this point, but it would obviously be a plus. This is what I have, and it works aside from being able to change the content on save with a template (“test.php”) being selected.

Any help would be appreciated:

add_filter( 'default_content', 'custom_editor_content');
// Testing the stuff for custom post type changing shit around

     function custom_editor_content($content){
          global $current_screen;
          // This is where the conditional check for new templates will go
          if ( $current_screen->post_type == 'page'){
               $content = 'This is the test page type';
          } elseif ($current_screen->post_type == 'post' ){
               $content = 'This is a post';
          }
          else {
               $content = '
               <div class="content-col-main">This is your main page content </div>
               <div class="content-col-side">This is your sidebar content </div>';
          }
     return $content;
     }
add_editor_style( 'editor-styles.css' );

I also tried looking at this, but it was only useful for adding custom meta boxes on template change (save), instead of adjusting the editor content.