File indexing completed on 2024-06-16 04:50:11

 /*
     SPDX-FileCopyrightText: 2007 Volker Krause <vkrause@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
 #pragma once
 
 #include "akonadicore_export.h"
 #include "monitor.h"
 
 class QSettings;
 
 namespace Akonadi
 {
 class ChangeRecorderPrivate;
 
 /**
  * @short Records and replays change notification.
  *
  * This class is responsible for recording change notifications while
  * an agent is not online and replaying the notifications when the agent
  * is online again. Therefore the agent doesn't have to care about
  * online/offline mode in its synchronization algorithm.
  *
  * Unlike Akonadi::Monitor this class only emits one change signal at a
  * time. To receive the next one you need to explicitly call replayNext().
  * If a signal is emitted that has no receivers, it's automatically skipped,
  * which means you only need to connect to signals you are actually interested
  * in.
  *
  * @author Volker Krause <vkrause@kde.org>
  */
 class AKONADICORE_EXPORT ChangeRecorder : public Monitor
 {
     Q_OBJECT
 public:
     /**
      * Creates a new change recorder.
      */
     explicit ChangeRecorder(QObject *parent = nullptr);
 
     /**
      * Destroys the change recorder.
      * All not yet processed changes are written back to the config file.
      */
     ~ChangeRecorder() override;
 
     /**
      * Sets the QSettings object used for persistent recorded changes.
      */
     void setConfig(QSettings *settings);
 
     /**
      * Returns whether there are recorded changes.
      */
     [[nodiscard]] bool isEmpty() const;
 
     /**
      * Removes the previously emitted change from the records.
      */
     void changeProcessed();
 
     /**
      * Enables change recording. If change recording is disabled, this class
      * behaves exactly like Akonadi::Monitor.
      * Change recording is enabled by default.
      * @param enable @c false to disable change recording. @c true by default
      */
     void setChangeRecordingEnabled(bool enable);
 
     /**
      * Debugging: dump current list of notifications, as saved on disk.
      */
     [[nodiscard]] QString dumpNotificationListToString() const;
 
 public Q_SLOTS:
     /**
      * Replay the next change notification and erase the previous one from the record.
      */
     void replayNext();
 
 Q_SIGNALS:
     /**
      * Emitted when new changes are recorded.
      */
     void changesAdded();
 
     /**
      * Emitted when replayNext() was called, but there was no valid change to replay.
      * This can happen when all pending changes have been filtered out, for example.
      * You only need to connect to this signal if you rely on one signal being emitted
      * as a result of calling replayNext().
      */
     void nothingToReplay();
 
 protected:
     /// @cond PRIVATE
     explicit ChangeRecorder(ChangeRecorderPrivate *d, QObject *parent = nullptr);
     /// @endcond
 
 private:
     /// @cond PRIVATE
     Q_DECLARE_PRIVATE(ChangeRecorder)
     /// @endcond
 };
 
 }