/*
 * @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 "catalogue/ArchiveFileBuilder.hpp"
#include "catalogue/Catalogue.hpp"
#include "catalogue/TapeFileSearchCriteria.hpp"
#include "common/dataStructures/ArchiveFile.hpp"
#include "common/log/Logger.hpp"
#include "rdbms/ConnPool.hpp"
#include "rdbms/Stmt.hpp"
#include "rdbms/Rset.hpp"

namespace cta::catalogue {

/**
 * Iteratess across the tape files that make up the contents of a given tape.
 */
class RdbmsCatalogueTapeContentsItor: public ArchiveFileItor::Impl {
public:
  /**
   * Constructor.
   *
   * @param log Object representing the API to the CTA logging system.
   * @param connPool The database connection pool.
   * @param vid The volume identifier of the tape.
   */
  RdbmsCatalogueTapeContentsItor(
    log::Logger &log,
    rdbms::ConnPool &connPool,
    const std::string &vid);

  /**
   * Destructor.
   */
  ~RdbmsCatalogueTapeContentsItor() override;

  /**
   * Returns true if a call to next would return another archive file.
   */
  bool hasMore() override;

  /**
   * Returns the next archive or throws an exception if there isn't one.
   */
  common::dataStructures::ArchiveFile next() override;

private:

  /**
   * Object representing the API to the CTA logging system.
   */
  log::Logger &m_log;

  /**
   * The volume identifier of the tape.
   */
  std::string m_vid;

  /**
   * True if the result set is empty.
   */
  bool m_rsetIsEmpty;

  /**
   * True if hasMore() has been called and the corresponding call to next() has
   * not.
   *
   * This member-variable is used to prevent next() being called before
   * hasMore().
   */
  bool m_hasMoreHasBeenCalled;

  /**
   * The database connection.
   */
  rdbms::Conn m_conn;

  /**
   * The database statement.
   */
  rdbms::Stmt m_stmt;

  /**
   * The result set of archive files that is to be iterated over.
   */
  rdbms::Rset m_rset;

  /**
   * Releases the database resources.
   *
   * This method is idempotent.
   */
  void releaseDbResources() noexcept;

}; // class RdbmsCatalogueTapeContentsItor

} // namespace cta::catalogue