function preProcess()
 {
     $cid = CRM_Utils_Request::retrieve('cid', 'Positive', $this, FALSE);
     $oid = CRM_Utils_Request::retrieve('oid', 'Positive', $this, FALSE);
     if ($oid) {
         $this->_id = CRM_Utils_Request::retrieve('oid', 'Positive', $this, FALSE);
     } else {
         $this->assign('hide_contact', TRUE);
         $this->_id = $cid;
     }
     if (!CRM_Utils_Rule::positiveInteger($this->_id)) {
         CRM_Core_Error::fatal('We need a valid discount ID for view');
     }
     $this->assign('id', $this->_id);
     $defaults = array();
     $params = array('id' => $this->_id);
     require_once 'CRM/CiviDiscount/BAO/Item.php';
     CRM_CiviDiscount_BAO_Item::retrieve($params, $defaults);
     require_once 'CRM/CiviDiscount/BAO/Track.php';
     if ($cid) {
         $rows = CRM_CiviDiscount_BAO_Track::getUsageByContact($this->_id);
     } else {
         $rows = CRM_CiviDiscount_BAO_Track::getUsageByOrg($this->_id);
     }
     $this->assign('rows', $rows);
     $this->assign('code_details', $defaults);
     $this->ajaxResponse['tabCount'] = count($rows);
     if (!empty($defaults['code'])) {
         CRM_Utils_System::setTitle($defaults['code']);
     }
 }