Piwik\Plugins\LanguagesManager\LanguagesManager::getLanguageForSession PHP Method

    public static function getLanguageForSession()
    {
        $cookieName = Config::getInstance()->General['language_cookie_name'];
        $cookie = new Cookie($cookieName);
        if ($cookie->isCookieFound()) {
            return $cookie->get('language');
        }
        return null;
    }

 /**
  * Assigns variables to {@link Piwik\View} instances that display an entire page.
  * 
  * The following variables assigned:
  * 
  * **date** - The value of the **date** query parameter.
  * **idSite** - The value of the **idSite** query parameter.
  * **rawDate** - The value of the **date** query parameter.
  * **prettyDate** - A pretty string description of the current period.
  * **siteName** - The current site's name.
  * **siteMainUrl** - The URL of the current site.
  * **startDate** - The start date of the current period. A {@link Piwik\Date} instance.
  * **endDate** - The end date of the current period. A {@link Piwik\Date} instance.
  * **language** - The current language's language code.
  * **config_action_url_category_delimiter** - The value of the `[General] action_url_category_delimiter`
  *                                            INI config option.
  * **topMenu** - The result of `MenuTop::getInstance()->getMenu()`.
  * 
  * As well as the variables set by {@link setPeriodVariablesView()}.
  * 
  * Will exit on error.
  * 
  * @param View $view
  * @return void
  * @api
  */
 protected function setGeneralVariablesView($view)
 {
     $view->date = $this->strDate;
     try {
         $view->idSite = $this->idSite;
         if (empty($this->site) || empty($this->idSite)) {
             throw new Exception("The requested website idSite is not found in the request, or is invalid.\n\t\t\t\tPlease check that you are logged in Piwik and have permission to access the specified website.");
         }
         $this->setPeriodVariablesView($view);
         $rawDate = Common::getRequestVar('date');
         $periodStr = Common::getRequestVar('period');
         if ($periodStr != 'range') {
             $date = Date::factory($this->strDate);
             $period = Period\Factory::build($periodStr, $date);
         } else {
             $period = new Range($periodStr, $rawDate, $this->site->getTimezone());
         }
         $view->rawDate = $rawDate;
         $view->prettyDate = self::getCalendarPrettyDate($period);
         $view->siteName = $this->site->getName();
         $view->siteMainUrl = $this->site->getMainUrl();
         $datetimeMinDate = $this->site->getCreationDate()->getDatetime();
         $minDate = Date::factory($datetimeMinDate, $this->site->getTimezone());
         $this->setMinDateView($minDate, $view);
         $maxDate = Date::factory('now', $this->site->getTimezone());
         $this->setMaxDateView($maxDate, $view);
         // Setting current period start & end dates, for pre-setting the calendar when "Date Range" is selected
         $dateStart = $period->getDateStart();
         if ($dateStart->isEarlier($minDate)) {
             $dateStart = $minDate;
         }
         $dateEnd = $period->getDateEnd();
         if ($dateEnd->isLater($maxDate)) {
             $dateEnd = $maxDate;
         }
         $view->startDate = $dateStart;
         $view->endDate = $dateEnd;
         $language = LanguagesManager::getLanguageForSession();
         $view->language = !empty($language) ? $language : LanguagesManager::getLanguageCodeForCurrentUser();
         $this->setBasicVariablesView($view);
         $view->topMenu = MenuTop::getInstance()->getMenu();
         $view->userMenu = MenuUser::getInstance()->getMenu();
         $notifications = $view->notifications;
         if (empty($notifications)) {
             $view->notifications = NotificationManager::getAllNotificationsToDisplay();
             NotificationManager::cancelAllNonPersistent();
         }
     } catch (Exception $e) {
         Piwik_ExitWithMessage($e->getMessage(), $e->getTraceAsString());
     }
 }