PHP：检测用户语言并能够更改语言

Question

I have a website with ability to choose language. And I wanted to make that when user enters first time to the website, php gets his system language and writes to cookie (So user by default every time when he enters time will have same language). But when user want to change website language, he will press a button with chosen language (For example Russian), then website language will be set for russian, and when he will enter website again, he will have russian language.

So far I have this code, but it's really confusing and it doesnt work properly.

HTML:

<a href="index.php?language=en">
<a href="index.php?language=ru">

PHP:

<?php
ini_set('display_errors',1);
error_reporting(E_ALL);

$language = substr($_SERVER['HTTP_ACCEPT_LANGUAGE'], 0, 2);

if (empty($_COOKIE['language'])){
setcookie('language', $language);
}

if ( !empty($_GET['language']) ) {
    $_COOKIE['language'] = $_GET['language'] === 'en' ? 'en' : 'ru';
} else {
  switch ($language){
  case "ru":
      $language = 'ru';
      break;
  case "en":
      $language = 'en';
      break;
  default:
      $language = 'en';
      break;
}
}

if ( $_COOKIE['language'] == "en") {
   $language = 'en';
} else {
   $language = 'ru';
}

$xml = simplexml_load_file("language.xml") or die("Equestria forgot languages");

$s_nav_main = $xml->s_nav_main->$language;
$s_nav_more = $xml->s_nav_more->$language;
$s_nav_bot = $xml->s_nav_bot->$language;
$s_nav_partners = $xml->s_nav_partners->$language;
$s_nav_developer = $xml->s_nav_developer->$language;
$s_aboutus = $xml->s_aboutus->$language;
$s_title = $xml->s_title->$language;
$s_head_title = $xml->s_head_title->$language;
$s_head_info = $xml->s_head_info->$language;
$s_statistics_people = $xml->s_statistics_people->$language;
$s_statistics_online = $xml->s_statistics_online->$language;
$s_statistics_messages = $xml->s_statistics_messages->$language;
$s_why_we_best = $xml->s_why_we_best->$language;
$s_why_we_best_content_title = $xml->s_why_we_best_content_title->$language;
$s_why_we_best_content_info = $xml->s_why_we_best_content_info->$language;
$s_why_we_best_adm_title = $xml->s_why_we_best_adm_title->$language;
$s_why_we_best_adm_info = $xml->s_why_we_best_adm_info->$language;
$s_why_we_best_comfort_title = $xml->s_why_we_best_comfort_title->$language;
$s_why_we_best_comfort_info = $xml->s_why_we_best_comfort_info->$language;
$s_why_we_best_wtf_title = $xml->s_why_we_best_wtf_title->$language;
$s_why_we_best_wtf_info = $xml->s_why_we_best_wtf_info->$language;
$s_trusted_title = $xml->s_trusted_title->$language;
$s_trusted_info = $xml->s_trusted_info->$language;
$s_people_celestia = $xml->s_people_celestia->$language;
$s_people_celestia_comment = $xml->s_people_celestia_comment->$language;
$s_people_luna = $xml->s_people_luna->$language;
$s_people_luna_comment = $xml->s_people_luna_comment->$language;
$s_people_twilight = $xml->s_people_twilight->$language;
$s_people_twilight_comment = $xml->s_people_twilight_comment->$language;
$s_botinfo_info = $xml->s_botinfo_info->$language;
$s_botinfo_more = $xml->s_botinfo_more->$language;
?>

Answer 1

Found the way how to do this:

$lang = substr($_SERVER['HTTP_ACCEPT_LANGUAGE'], 0, 2);

if ( !empty($_GET['language']) ) {
    $_COOKIE['language'] = $_GET['language'] === 'en' ? 'en' : 'ru';
} elseif (empty($_COOKIE['language'])) {
    $_COOKIE['language'] = $lang;
}
setcookie('language', $_COOKIE['language']);

if ( $_COOKIE['language'] == "en") {
   $language = 'en';
} else {
   $language = 'ru';
}