\d{2})?(?=\d)(?=\d{4})(?=\d{4})/', $phone); $output = []; if (array_key_exists('country', $parts)) { $output [] = "+{$parts[0]}"; } $output [] = $parts[1] ?? ''; $output [] = $parts[2] ?? ''; $output [] = $parts[3] ?? ''; return implode(' ', $output); } }