/*
 * @project      The CERN Tape Archive (CTA)
 * @copyright    Copyright © 2021-2022 CERN
 * @license      This program is free software, distributed under the terms of the GNU General Public
 *               Licence version 3 (GPL Version 3), copied verbatim in the file "COPYING". You can
 *               redistribute it and/or modify it under the terms of the GPL Version 3, or (at your
 *               option) any later version.
 *
 *               This program is distributed in the hope that it will be useful, but WITHOUT ANY
 *               WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 *               PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 *               In applying this licence, CERN does not waive the privileges and immunities
 *               granted to it by virtue of its status as an Intergovernmental Organization or
 *               submit itself to any jurisdiction.
 */

#pragma once

#include "SubprocessHandler.hpp"
#include "ProcessManager.hpp"
#include "TapedConfiguration.hpp"
#include "common/threading/SocketPair.hpp"

namespace cta::tape::daemon {

/**
 * Handler for garbage collector subprocesses. This long lived process should live
 * as long as the main process, but will be respawned in case of crash.
 */
class MaintenanceHandler: public SubprocessHandler {
public:
  MaintenanceHandler(const TapedConfiguration & tapedConfig, ProcessManager & pm);
  virtual ~MaintenanceHandler();
  SubprocessHandler::ProcessingStatus getInitialStatus() override;
  SubprocessHandler::ProcessingStatus fork() override;
  void postForkCleanup() override;
  int runChild() noexcept override;
  SubprocessHandler::ProcessingStatus shutdown() override;
  void kill() override;
  SubprocessHandler::ProcessingStatus processEvent() override;
  SubprocessHandler::ProcessingStatus processSigChild() override;
  SubprocessHandler::ProcessingStatus processTimeout() override;
private:
  void exceptionThrowingRunChild();
  
  /**
   * Returns true if the RepackRequestManager will be ran on this tapeserver,
   * false otherwise
   */
  bool runRepackRequestManager() const;
  /** Reference to the process manager*/
  cta::tape::daemon::ProcessManager & m_processManager;
  /** The parameters */
  const TapedConfiguration & m_tapedConfig;
  /** The current state we report to process manager */
  SubprocessHandler::ProcessingStatus m_processingStatus;
  /** PID for the subprocess */
  pid_t m_pid=-1;
  /** Keep track of the shutdown state */
  bool m_shutdownInProgress=false;
  /** A socketpair to ask the child process to gracefully shut down */
  std::unique_ptr<cta::server::SocketPair> m_socketPair;
  /** The poll period for the garbage collector */
  static const time_t s_pollInterval = 10;
};

} // namespace cta::tape::daemon