protected function prep_props(array $props)
{
// Skip tree fields and primary keys
$skip_fields = \Arr::merge(Model_Menu::primary_key(), Model_Menu::tree_config(), array('children'));
\Arr::delete($skip_fields, array('read-only', 'title_field'));
// Model properties
$properties = \Arr::filter_keys($props, array_keys(Model_Menu::properties()));
$properties = \Arr::filter_keys($properties, $skip_fields, true);
//Model 'fields' property fields
$fields = \Arr::filter_keys($props, array_keys($properties), true);
$fields = \Arr::filter_keys($fields, $skip_fields, true);
is_array($properties['fields']) or $properties['fields'] = array();
$properties['fields'] = \Arr::merge($properties['fields'], $fields);
return $properties;
}