asset.php: when param list is supplied, return list of files

asset.php

@@ -19,16 +19,29 @@ if (!array_key_exists('dir', $_REQUEST)) {
   $_REQUEST['dir'] = '.';
 }
 
-$tmpfile = tempnam('/tmp', 'osb-asset-');
-$contents = $repo->file_get_contents("{$_REQUEST['dir']}/{$_REQUEST['file']}");
+if (array_key_exists('list', $_REQUEST)) {
+  $contents = array();
+  foreach ($repo->scandir($_REQUEST['dir']) as $f) {
+    if (substr($f, 0, 1) !== '.') {
+      $contents[] = array('name' => $f);
+    }
+  }
 
-if ($contents === false) {
-  Header("HTTP/1.1 401 Permission denied");
-  exit(0);
+  $mime_type = 'application/json; charset=utf-8';
+  $contents = json_encode($contents);
 }
+else {
+  $tmpfile = tempnam('/tmp', 'osb-asset-');
+  $contents = $repo->file_get_contents("{$_REQUEST['dir']}/{$_REQUEST['file']}");
+
+  if ($contents === false) {
+    Header("HTTP/1.1 401 Permission denied");
+    exit(0);
+  }
 
-file_put_contents($tmpfile, $contents);
-$mime_type = mime_content_type($tmpfile);
+  file_put_contents($tmpfile, $contents);
+  $mime_type = mime_content_type($tmpfile);
+}
 
 Header("Content-Type: {$mime_type}; charset=utf-8");
 print $contents;