Arkadaşlar Aşağıdaki Kodlarda resim ismini image.jpg olarak wordprese ekleyebiliyor. sorun image.jpg ismi yerine başka bir koymam lazım yardımcı olabilen varmı ???

$image_url="http://www.denemesite.com/image.jpg"

$upload_dir = wp_upload_dir();
$image_data = file_get_contents($image_url);
$filename = basename($image_url);
if(wp_mkdir_p($upload_dir['path']))
$file = $upload_dir['path'] . '/' . $filename;
else
$file = $upload_dir['basedir'] . '/' . $filename;
file_put_contents($file, $image_data);

$wp_filetype = wp_check_filetype($filename, null );
$attachment = array(
'post_mime_type' => $wp_filetype['type'],
'post_title' => sanitize_file_name($filename),
'post_content' => '',
'post_status' => 'inherit'
);
$attach_id = wp_insert_attachment( $attachment, $file, $post_id );
require_once(ABSPATH . 'wp-admin/includes/image.php');
$attach_data = wp_generate_attachment_metadata( $attach_id, $file );
wp_update_attachment_metadata( $attach_id, $attach_data );

set_post_thumbnail( $post_id, $attach_id );