Gallery attach to post not working

OK,
just have a look to an abstract of the code:

switch ($site_url) {
            case $site_url === TRUE:
            case 'site':
                $retval = site_url();
                break;
            case $site_url === FALSE:
            case 'home':
                $retval = home_url();
                break;
            case 'plugins':
            case 'plugin':
                $retval = plugins_url();
                $add_index_dot_php = FALSE;
                break;
             ......
             ......
             default:
                $retval = site_url();
         }

Looking to this code, we may expect that the goal of the developer was: “if $site_url is equal to FALSE the result should be home_url()”.
Unfortunately, this will never happens. Why ? because if $site_url is set to FALSE, the case $site_url === FALSE will be evaluated as TRUE and so does not fit with the searched value. The switch statement will fall back to the default case, whose result is not the one expected.

To overcome this issue, and if you want to follow the same structure, the switch statement need to be written like:

switch (TRUE) {
            case $site_url === TRUE:
            case $site_url === 'site':
                $retval = site_url();
                break;
            case $site_url === FALSE:
            case $site_url === 'home':
                $retval = home_url();
                break;
            case $site_url === 'plugins':
            case $site_url === 'plugin':
                $retval = plugins_url();
                $add_index_dot_php = FALSE;
                break;
            case $site_url === 'plugins_mu':
            case $site_url === 'plugin_mu':
                $retval = WPMU_PLUGIN_URL;
                $retval = set_url_scheme($retval);
                $retval = apply_filters( 'plugins_url', $retval, '', '');
                $add_index_dot_php = FALSE;
                break;
            case $site_url === 'templates':
            case $site_url === 'template':
            case $site_url === 'themes':
            case $site_url === 'theme':
                $retval = get_template_directory_uri();
                $add_index_dot_php = FALSE;
                break;
            case $site_url === 'styles':
            case $site_url === 'style':
            case $site_url === 'stylesheets':
            case $site_url === 'stylesheet':
                $retval = get_stylesheet_directory_uri();
                $add_index_dot_php = FALSE;
                break;
            case $site_url === 'content':
                $retval = content_url();
                $add_index_dot_php = FALSE;
                break;
            case $site_url === 'root':
                $retval = get_option('home');
                if (is_ssl())
                    $scheme = 'https';
                else
                    $scheme = parse_url($retval, PHP_URL_SCHEME);
                $retval = set_url_scheme($retval, $scheme);
                break;
            case $site_url === 'gallery':
            case $site_url === 'galleries':
                $root_type = defined('NGG_GALLERY_ROOT_TYPE') ? NGG_GALLERY_ROOT_TYPE : 'site';
                $add_index_dot_php = FALSE;
                if ($root_type === 'content')
                    $retval = content_url();
                else
                    $retval = site_url();
                break;
            default:
                $retval = site_url();
        }