PHP to create Java array (tinymce image list)

I'm using tinymce do do some wysiwyg editing on my site.  To insert images it displays a drop down list of images which I need to propagate with all the images in a given image directory.

Here's the code in the main script:
"external_image_list_url : tinymce/lists/link_list.js"

And here's link_list.js:

var tinyMCEImageList = new Array(
      // Name, URL
      ["Logo 1", "media/logo.jpg"],
      ["Logo 2 Over", "media/logo_over.jpg"]
);

Now I need that array to show all the files in the images/dogs directory.  Here's the PHP code I'd want to run there:

function getfiles($dirname=".") {
$pattern="(\.jpg$)|(\.png$)|(\.jpeg$)|(\.gif$)"; //valid image extensions
$files = array();
if($handle = opendir($dirname)) {
   while(false !== ($file = readdir($handle))){
      if(eregi($pattern, $file)) //if this file is a valid image
         echo "$file <br />";
   }
 closedir($handle);
}
return($files);
}

How do I get the two to work together?

Hope the question makes sense