Language swtich in WP

language-wp.php

<?php

function lang_support() {
	return array('en','fr'); 
	// Add your support lang-code (1st place is a default)
}
 
function rewrite_lang(){
	$langs = lang_support();
	foreach($langs as $lang) {
		add_rewrite_endpoint($lang,EP_PERMALINK|EP_PAGES|		EP_ROOT|EP_CATEGORIES);
	}
}
add_action('init','rewrite_lang');
 
function lang(){
	global $wp_query;
	$langs = lang_support();
	$lang_r = "";
	foreach($langs as $lang) {
		if(isset($wp_query->query_vars[$lang])) {
			$lang_r = $lang;
			$_SESSION['lang'] = $lang_r;
		}
	}
	if(in_array($lang_r,$langs)) {
		return $lang_r;
	} else {
		return $langs[0];
	}
}
 
function init_session(){
	session_start();
}
add_action('init','init_session',1);
 
function lang_session() { // Redirect by JS if session is set
	$url_lang= basename($_SERVER['REQUEST_URI']);
	if(!in_array($url_lang,lang_support()) && 		isset($_SESSION['lang'])) {
	if(!is_404()) {
		wp_redirect(currentURL().$_SESSION['lang'],301);
		exit;
	}
}
}
add_action('wp_head','lang_session');
 
function output_buffer() {
	ob_start();
}
add_action('init','output_buffer');
 
function currentURL() {
	$pageURL=(@$_SERVER["HTTPS"]=="on")?"https://":"http://";
	if($_SERVER["SERVER_PORT"]!="80"){
		$pageURL.=$_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
	}else{
		$pageURL.=$_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];
	}
return $pageURL;
}
?>