/**
* Try to parse a language tag.
*
* @param Language|string|null|mixed $language [optional] A language instance, a language tag, null to return the preferred language tag or any other value.
*
* @return string|null The language tag to parse, or null to return the preferred language tag.
*/
public static function parseLanguageTag($language = null)
{
// Return the default language if the parameter is null
if ($language === null) {
return static::getPreferredLanguage()->getTag();
}
// Parse languages instances
if ($language instanceof Language) {
return $language->getTag();
}
// Return a language tag if it's valid
if (is_string($language) && LanguageManager::isWithTag($language)) {
return $language;
}
// Unable to parse the language tag
return null;
}
