private function buildCurtain(PhabricatorCalendarExport $export)
 {
     $viewer = $this->getRequest()->getUser();
     $id = $export->getID();
     $curtain = $this->newCurtainView($export);
     $can_edit = PhabricatorPolicyFilter::hasCapability($viewer, $export, PhabricatorPolicyCapability::CAN_EDIT);
     $ics_uri = $export->getICSURI();
     $edit_uri = "export/edit/{$id}/";
     $edit_uri = $this->getApplicationURI($edit_uri);
     $curtain->addAction(id(new PhabricatorActionView())->setName(pht('Edit Export'))->setIcon('fa-pencil')->setDisabled(!$can_edit)->setWorkflow(!$can_edit)->setHref($edit_uri));
     $curtain->addAction(id(new PhabricatorActionView())->setName(pht('Export as .ics'))->setIcon('fa-download')->setHref($ics_uri));
     $disable_uri = "export/disable/{$id}/";
     $disable_uri = $this->getApplicationURI($disable_uri);
     if ($export->getIsDisabled()) {
         $disable_name = pht('Enable Export');
         $disable_icon = 'fa-check';
     } else {
         $disable_name = pht('Disable Export');
         $disable_icon = 'fa-ban';
     }
     $curtain->addAction(id(new PhabricatorActionView())->setName($disable_name)->setIcon($disable_icon)->setDisabled(!$can_edit)->setWorkflow(true)->setHref($disable_uri));
     return $curtain;
 }