How do you load extra javascript files required for wysiwyg api plugin on node/edit pages? I'm building a plugin using the WYSIWYG API module for Drupal 7 that will add a button to the toolbar of supported editors. 

I'm using the hook_wysiwyg_plugin() hook to create a new button on editor toolbar but I need to load a few other javascript files. The hook_wysiwyg_plugin() hook seems to allow you to specify one JS and CSS file.

How can I load extra required javascript files required for the plugin javascript?

I've implemented hook_library() to define a library i.e. js/css files but am unsure how I hook that up to wysiwyg api so that they load on the node/edit screens?
With drupal_add_js:

function yourmodule_preprocess_page(&amp;$vars)
{
  $node = $vars['node']; 
  if($node-&gt;type == 'yournodetype' AND arg(2) == 'edit')
  {
    drupal_add_js([...]);
  }
}