How to make HTTP_ACCEPT_LANGUAGE redirect correctly?

Question

PHP

Greetings!

Need help!)

There is such a thing, but I would like it to let bots through!

preg_match('/^\w{2}/', $_SERVER['HTTP_ACCEPT_LANGUAGE'], $m);
switch (strtolower($m[0])) {
case 'ru': break;
default: header('Location: /en'); break;
}

Answer 1

add a check for "bot|spider|crawler" to HTTP_USER_AGENT, but instead of $_SERVER it's better to use filter_input(INPUT_SERVER, 'HTTP_USER_AGENT')