check_language function - language settings are ignored about postfixadmin HOT 3 CLOSED

--- a/functions.inc.php
+++ b/functions.inc.php
@@ -139,16 +139,22 @@ function _flash_string($type, $string) {
 function check_language ($use_post = 1) {
     global $supported_languages; # from languages/languages.php
 
+    if ( $use_post && safepost('lang')) {
+        if(array_key_exists(safepost('lang'), $supported_languages)) {
+            return safepost('lang'); # first preference: $_POST['lang']
+        }
+    }
+
+    if (safecookie('lang')) {
+        if(array_key_exists(safecookie('lang'), $supported_languages)) {
+            return safecookie('lang'); # second-best: $_COOKIE['lang']
+        }
+    }
+
     $lang = Config::read('default_language');
 
     if(isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
         $lang_array = preg_split ('/(\s*,\s*)/', $_SERVER['HTTP_ACCEPT_LANGUAGE']);
-        if (safecookie('lang')) {
-            array_unshift($lang_array, safecookie('lang')); # prefer language from cookie
-        }
-        if ( $use_post && safepost('lang')) {
-            array_unshift($lang_array, safepost('lang')); # but prefer $_POST['lang'] even more
-        }
 
         for($i = 0; $i < count($lang_array); $i++) {
             $lang_next = $lang_array[$i];

if ( $use_post && safepost('lang')) {
    $lang_array[strtolower(safepost('lang'))] = 1;
}
if (safecookie('lang')) {
    $lang_array[strtolower(safecookie('lang')] = 1;
}
if(!empty($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
    $langtags = explode(',',strtolower($_SERVER['HTTP_ACCEPT_LANGUAGE']));
    for($i = 0; $i < count($langtags); $i++ )  {
    	$langcode = NULL;
        $langpriority = NULL;
		$langdef = explode(';',$langtags[$i]);
		if (isset($langdef[0])) {
			$langcode = trim($langdef[0]);
		}
        if (isset($langdef[1])) {
			$langpriority = trim($langdef[1]);
		}
		if (!empty($langcode)) {
			$langcode = substr($langcode,0,2);
			if (ctype_alpha($langcode)) {
				$xpriority = 1;
				if (!empty($langpriority) && strpos($langpriority,'q=') === 0) {
					$q = (float)trim(substr($langpriority,2));
					if (is_numeric($q) && $q >= 0 && $q <= 1) {
                    	$xpriority = $q;
					}
				}
				if (!isset($lang_array[$langcode])) {
					$lang_array[$langcode] = $xpriority;
				}
				elseif ($lang_array[$langcode] < $xpriority) {
                	$lang_array[$langcode] = $xpriority;
				}
			}
		}
	}
}

if (count($lang_array) > 0) {
    $bestpriority  = -1;
    foreach ($lang_array as $langcode => $langpriority) {
		if (array_key_exists($langcode, $supported_languages)) {
			if ($bestpriority < $langpriority) {
				$lang = $langcode;
    			$bestpriority = $langpriority;
			}
		}
	}
}

return $lang;