Improve Performance of check on published content langs.

Fixees joomla#7130. References joomla#6904

plugins/system/languagefilter/languagefilter.php

@@ -33,14 +33,6 @@ class PlgSystemLanguageFilter extends JPlugin
 
 	private $user_lang_code;
 
-	/**
-	 * JDatabaseDriver instance
-	 *
-	 * @var    JDatabaseDriver
-	 * @since  3.4.2
-	 */
-	protected $db = null;
-
 	/**
 	 * Application object.
 	 *
@@ -522,24 +514,17 @@ public function onUserLogin($user, $options = array())
 			$assoc = JLanguageAssociations::isEnabled();
 			$lang_code = $user['language'];
 
+			// If no language is specified for this user, we set it to the site default language
 			if (empty($lang_code))
 			{
 				$lang_code = $this->default_lang;
 			}
 
-			// Get a 1-dimensional array of published language codes
-			$query = $this->db->getQuery(true)
-				->select($this->db->quoteName('a.lang_code'))
-				->from($this->db->quoteName('#__languages', 'a'))
-				->where($this->db->quoteName('published') . ' = 1');
-			$this->db->setQuery($query);
-			$lang_codes = $this->db->loadColumn();
-
-			// The user language has been deleted/disabled or the related content language does not exist/has been unpublished
+			// The language has been deleted/disabled or the related content language does not exist/has been unpublished
 			// or the related home page does not exist/has been unpublished
-			if (!array_key_exists($lang_code, MultilangstatusHelper::getSitelangs())
-				|| !in_array($lang_code, $lang_codes)
-				|| !array_key_exists($lang_code, MultilangstatusHelper::getHomepages()))
+			if (!array_key_exists($lang_code, $this->lang_codes)
+				|| !array_key_exists($lang_code, MultilangstatusHelper::getHomepages())
+				|| !JFolder::exists(JPATH_SITE . '/language/' . $lang_code))
 			{
 				$lang_code = $this->current_lang;
 			}