/**
* Collect the alerts and group them together
*/
public static function collect_alerts()
{
$notification_center = Yoast_Notification_Center::get();
$notifications = $notification_center->get_sorted_notifications();
self::$notification_count = count($notifications);
self::$errors = array_filter($notifications, array(__CLASS__, 'filter_error_alerts'));
self::$dismissed_errors = array_filter(self::$errors, array(__CLASS__, 'filter_dismissed_alerts'));
self::$active_errors = array_diff(self::$errors, self::$dismissed_errors);
self::$warnings = array_filter($notifications, array(__CLASS__, 'filter_warning_alerts'));
self::$dismissed_warnings = array_filter(self::$warnings, array(__CLASS__, 'filter_dismissed_alerts'));
self::$active_warnings = array_diff(self::$warnings, self::$dismissed_warnings);
}
