/**
  * Get the opposition teams available for filtering, and if the opposition parameter is in the query string apply opposition filter
  * @param StatisticsManager $statistics_manager
  * @return Array containing teams, current team id, and text for filter description
  */
 public static function SupportOppositionFilter(StatisticsManager $statistics_manager)
 {
     $filter_data = array(array(), null, "");
     $filter_data[0] = $statistics_manager->ReadOppositionTeamsForFilter();
     if (isset($_GET['opposition']) and is_numeric($_GET['opposition'])) {
         if (array_key_exists($_GET['opposition'], $filter_data[0])) {
             $statistics_manager->FilterByOpposition(array($filter_data[0][$_GET['opposition']]->GetId()));
             $filter_data[1] = $filter_data[0][$_GET['opposition']]->GetId();
             $filter_data[2] = "against " . $filter_data[0][$_GET['opposition']]->GetName() . " ";
         }
     }
     return $filter_data;
 }