MPRIS D-Bus interface to control audio player from panel.

ChangeLog

@@ -6,6 +6,7 @@ Fri Dec 23 08:33:40 CET 2016  Urs Fleisch  <ufleisch@users.sourceforge.net>
 	  + If the first command line argument is "--portable", the
 	    configuration is stored in a file kid3.ini in the program folder.
 	  + Image data can be copied to clipboard.
+	  + MPRIS2 D-Bus interface for the audio player.
 
 	* Improved:
 	  + "Import CSV" can import to different files if no matching

src/core/model/Sources.cmake

@@ -32,6 +32,7 @@ set(model_SRCS
   model/frameeditorobject.cpp
   model/frameobjectmodel.cpp
   model/iusercommandprocessor.cpp
+  model/mprisinterface.cpp
 )
 
 set(model_MOC_HDRS
@@ -54,6 +55,7 @@ set(model_MOC_HDRS
   model/genremodel.h
   model/frameeditorobject.h
   model/frameobjectmodel.h
+  model/mprisinterface.h
 )
 
 if (HAVE_QTDBUS)

src/core/model/audioplayer.cpp

@@ -38,13 +38,17 @@
 #include <QMediaPlayer>
 #include <QMediaPlaylist>
 #endif
+#include "kid3application.h"
+#include "taggedfile.h"
+#include "fileproxymodel.h"
 
 /**
  * Constructor.
  *
- * @param parent parent object
+ * @param app parent application
  */
-AudioPlayer::AudioPlayer(QObject* parent) : QObject(parent)
+AudioPlayer::AudioPlayer(Kid3Application* app) : QObject(app),
+  m_app(app)
 #ifdef HAVE_PHONON
 , m_fileNr(-1)
 #endif
@@ -63,6 +67,10 @@ AudioPlayer::AudioPlayer(QObject* parent) : QObject(parent)
           this, SLOT(currentSourceChanged()));
   connect(m_mediaObject, SIGNAL(tick(qint64)),
           this, SIGNAL(positionChanged(qint64)));
+  connect(m_mediaObject, SIGNAL(stateChanged(Phonon::State, Phonon::State)),
+          this, SLOT(onStateChanged()));
+  connect(m_audioOutput, SIGNAL(volumeChanged(qreal)),
+          this, SLOT(onVolumeChanged(qreal)));
 #else
   m_mediaPlayer = new QMediaPlayer(this);
   m_mediaPlaylist = new QMediaPlaylist(m_mediaPlayer);
@@ -71,6 +79,10 @@ AudioPlayer::AudioPlayer(QObject* parent) : QObject(parent)
           this, SLOT(currentIndexChanged(int)));
   connect(m_mediaPlayer, SIGNAL(positionChanged(qint64)),
           this, SIGNAL(positionChanged(qint64)));
+  connect(m_mediaPlayer, SIGNAL(stateChanged(QMediaPlayer::State)),
+          this, SLOT(onStateChanged()));
+  connect(m_mediaPlayer, SIGNAL(volumeChanged(int)),
+          this, SIGNAL(volumeChanged(int)));
 #endif
 }
 
@@ -109,10 +121,24 @@ void AudioPlayer::setFiles(const QStringList& files, int fileNr)
     m_mediaPlaylist->setCurrentIndex(0);
   }
 #endif
+  emit fileCountChanged(getFileCount());
 }
 
 /**
- * Get name of current file.
+ * Get number of files in play list.
+ * @return number of files.
+ */
+int AudioPlayer::getFileCount() const
+{
+#ifdef HAVE_PHONON
+  return m_files.size();
+#else
+  return m_mediaPlaylist->mediaCount();
+#endif
+}
+
+/**
+ * Get path of current file.
  * @return file name.
  */
 QString AudioPlayer::getFileName() const
@@ -127,6 +153,33 @@ QString AudioPlayer::getFileName() const
 #endif
 }
 
+/**
+ * Get tagged file for current file.
+ * @return tagged file, 0 if not available.
+ */
+TaggedFile* AudioPlayer::getTaggedFile() const
+{
+  FileProxyModel* model = m_app->getFileProxyModel();
+  QModelIndex index = model->index(getFileName());
+  if (index.isValid()) {
+    return FileProxyModel::getTaggedFileOfIndex(index);
+  }
+  return 0;
+}
+
+/**
+ * Get index of current file in playlist.
+ * @return index of current file.
+ */
+int AudioPlayer::getCurrentIndex() const
+{
+#ifdef HAVE_PHONON
+  return m_fileNr;
+#else
+  return m_mediaPlaylist->currentIndex();
+#endif
+}
+
 /**
  * Get the current playback position in milliseconds.
  * @return time in milliseconds.
@@ -147,9 +200,85 @@ quint64 AudioPlayer::getCurrentPosition() const
 void AudioPlayer::setCurrentPosition(quint64 position)
 {
 #ifdef HAVE_PHONON
-  return m_mediaObject->seek(position);
+  m_mediaObject->seek(position);
+#else
+  m_mediaPlayer->setPosition(position);
+#endif
+  emit currentPositionChanged(position);
+}
+
+/**
+ * Get playing state.
+ * @return state.
+ */
+AudioPlayer::State AudioPlayer::getState() const
+{
+#ifdef HAVE_PHONON
+  switch (m_mediaObject->state()) {
+  case Phonon::PlayingState:
+    return PlayingState;
+  case Phonon::PausedState:
+    return PausedState;
+  default:
+    return StoppedState;
+  }
+#else
+  switch (m_mediaPlayer->state()) {
+  case QMediaPlayer::StoppedState:
+    return StoppedState;
+  case QMediaPlayer::PlayingState:
+    return PlayingState;
+  case QMediaPlayer::PausedState:
+    return PausedState;
+  }
+#endif
+  return StoppedState;
+}
+
+/**
+ * Signal stateChanged() when the playing state is changed.
+ */
+void AudioPlayer::onStateChanged()
+{
+  emit stateChanged(getState());
+}
+
+/**
+ * Get duration of current track in milliseconds.
+ * @return duration.
+ */
+qint64 AudioPlayer::getDuration() const
+{
+#ifdef HAVE_PHONON
+  return m_mediaObject->totalTime();
+#else
+  return m_mediaPlayer->duration();
+#endif
+}
+
+/**
+ * Get volume.
+ * @return volume level between 0 and 100.
+ */
+int AudioPlayer::getVolume() const
+{
+#ifdef HAVE_PHONON
+  return m_audioOutput->volume() * 100;
+#else
+  return m_mediaPlayer->volume();
+#endif
+}
+
+/**
+ * Set volume.
+ * @param volume level between 0 and 100
+ */
+void AudioPlayer::setVolume(int volume)
+{
+#ifdef HAVE_PHONON
+  m_audioOutput->setVolume(static_cast<qreal>(volume) / 100);
 #else
-  return m_mediaPlayer->setPosition(position);
+  m_mediaPlayer->setVolume(volume);
 #endif
 }
 
@@ -223,6 +352,30 @@ void AudioPlayer::playOrPause()
 #endif
 }
 
+/**
+ * Resume playback.
+ */
+void AudioPlayer::play()
+{
+#ifdef HAVE_PHONON
+  m_mediaObject->play();
+#else
+  m_mediaPlayer->play();
+#endif
+}
+
+/**
+ * Pause playback.
+ */
+void AudioPlayer::pause()
+{
+#ifdef HAVE_PHONON
+  m_mediaObject->pause();
+#else
+  m_mediaPlayer->pause();
+#endif
+}
+
 /**
  * Stop playback.
  */
@@ -265,6 +418,15 @@ void AudioPlayer::aboutToFinish()
     }
   }
 }
+
+/**
+ * Signal volumeChanged() when the volume is changed.
+ * @param volume volume
+ */
+void AudioPlayer::onVolumeChanged(qreal volume)
+{
+  emit volumeChanged(volume * 100);
+}
 #else
 /**
  * Update display and button state when the current source is changed.

src/core/model/audioplayer.h

@@ -45,6 +45,9 @@ class QMediaPlayer;
 class QMediaPlaylist;
 #endif
 
+class Kid3Application;
+class TaggedFile;
+
 /**
  * Audio player toolbar.
  */
@@ -52,12 +55,19 @@ class KID3_CORE_EXPORT AudioPlayer : public QObject {
   Q_OBJECT
 
 public:
+  /** Playing state. */
+  enum State {
+    StoppedState, /**< Stopped */
+    PlayingState, /**< Playing */
+    PausedState   /**< Paused */
+  };
+
   /**
    * Constructor.
    *
-   * @param parent parent object
+   * @param app parent application
    */
-  explicit AudioPlayer(QObject* parent);
+  explicit AudioPlayer(Kid3Application* app);
 
   /**
    * Destructor.
@@ -73,11 +83,29 @@ public:
   void setFiles(const QStringList& files, int fileNr = 0);
 
   /**
-   * Get name of current file.
+   * Get number of files in play list.
+   * @return number of files.
+   */
+  int getFileCount() const;
+
+  /**
+   * Get path of current file.
    * @return file name.
    */
   QString getFileName() const;
 
+  /**
+   * Get tagged file for current file.
+   * @return tagged file, 0 if not available.
+   */
+  TaggedFile* getTaggedFile() const;
+
+  /**
+   * Get index of current file in playlist.
+   * @return index of current file.
+   */
+  int getCurrentIndex() const;
+
   /**
    * Get the current playback position in milliseconds.
    * @return time in milliseconds.
@@ -90,6 +118,30 @@ public:
    */
   void setCurrentPosition(quint64 position);
 
+  /**
+   * Get playing state.
+   * @return state.
+   */
+  State getState() const;
+
+  /**
+   * Get duration of current track in milliseconds.
+   * @return duration.
+   */
+  qint64 getDuration() const;
+
+  /**
+   * Get volume.
+   * @return volume level between 0 and 100.
+   */
+  int getVolume() const;
+
+  /**
+   * Set volume.
+   * @param volume level between 0 and 100
+   */
+  void setVolume(int volume);
+
 #ifdef HAVE_PHONON
   /**
    * Play a track from the files.
@@ -136,7 +188,31 @@ signals:
    * Emitted when the current track position changed.
    * @param position time in milliseconds
    */
-  void 	positionChanged(qint64 position);
+  void positionChanged(qint64 position);
+
+  /**
+   * Emitted when the current position is changed using setCurrentPosition().
+   * @param position time in milliseconds
+   */
+  void currentPositionChanged(qint64 position);
+
+  /**
+   * Emitted when the playing state is changed.
+   * @param state playing state
+   */
+  void stateChanged(AudioPlayer::State state);
+
+  /**
+   * Emitted when the volume is changed.
+   * @param volume level between 0 and 100
+   */
+  void volumeChanged(int volume);
+
+  /**
+   * Emitted when the file count changed.
+   * @param count number of files in play list
+   */
+  void fileCountChanged(int count);
 
 public slots:
   /**
@@ -144,6 +220,16 @@ public slots:
    */
   void playOrPause();
 
+  /**
+   * Resume playback.
+   */
+  void play();
+
+  /**
+   * Pause playback.
+   */
+  void pause();
+
   /**
    * Stop playback.
    */
@@ -170,6 +256,12 @@ private slots:
    * Queue next track when the current track is about to finish.
    */
   void aboutToFinish();
+
+  /**
+   * Signal volumeChanged() when the volume is changed.
+   * @param volume volume
+   */
+  void onVolumeChanged(qreal volume);
 #else
   /**
    * Update display and button state when the current source is changed.
@@ -177,8 +269,13 @@ private slots:
    */
   void currentIndexChanged(int position);
 #endif
+  /**
+   * Signal stateChanged() when the playing state is changed.
+   */
+  void onStateChanged();
 
 private:
+  Kid3Application* m_app;
 #ifdef HAVE_PHONON
   /**
    * Select a track from the files and optionally start playing it.

src/core/model/kid3application.cpp

@@ -86,6 +86,9 @@
 #include "iusercommandprocessor.h"
 #if defined HAVE_PHONON || QT_VERSION >= 0x050000
 #include "audioplayer.h"
+#ifdef HAVE_QTDBUS
+#include "mprisinterface.h"
+#endif
 #endif
 
 #include "importplugins.h"
@@ -516,7 +519,14 @@ AudioPlayer* Kid3Application::getAudioPlayer()
 {
   if (!m_player) {
     m_player = new AudioPlayer(this);
+#ifdef HAVE_QTDBUS
+    new MprisInterface(m_player);
+    new MprisPlayerInterface(m_player);
+#endif
   }
+#ifdef HAVE_QTDBUS
+  activateMprisInterface();
+#endif
   return m_player;
 }
 
@@ -526,10 +536,69 @@ AudioPlayer* Kid3Application::getAudioPlayer()
 void Kid3Application::deleteAudioPlayer() {
   if (m_player) {
     m_player->stop();
+#ifdef HAVE_QTDBUS
+    deactivateMprisInterface();
+#endif
     delete m_player;
     m_player = 0;
   }
 }
+
+#ifdef HAVE_QTDBUS
+/**
+ * Activate the MPRIS D-Bus Interface if not already active.
+ */
+void Kid3Application::activateMprisInterface()
+{
+  if (!m_mprisServiceName.isEmpty() || !m_player)
+    return;
+
+  if (QDBusConnection::sessionBus().isConnected()) {
+    m_mprisServiceName = QLatin1String("org.mpris.MediaPlayer2.kid3");
+    bool ok = QDBusConnection::sessionBus().registerService(m_mprisServiceName);
+    if (!ok) {
+      // If another instance of Kid3 is already running register a service
+      // with ".instancePID" appended, see
+      // https://specifications.freedesktop.org/mpris-spec/latest/
+      m_mprisServiceName += QLatin1String(".instance");
+      m_mprisServiceName += QString::number(::getpid());
+      ok = QDBusConnection::sessionBus().registerService(m_mprisServiceName);
+    }
+    if (ok) {
+      if (!QDBusConnection::sessionBus().registerObject(
+            QLatin1String("/org/mpris/MediaPlayer2"), m_player)) {
+        qWarning("Registering D-Bus MPRIS object failed");
+      }
+    } else {
+      m_mprisServiceName.clear();
+      qWarning("Registering D-Bus MPRIS service failed");
+    }
+  } else {
+    qWarning("Cannot connect to the D-BUS session bus.");
+  }
+}
+
+/**
+ * Deactivate the MPRIS D-Bus Interface if it is active.
+ */
+void Kid3Application::deactivateMprisInterface()
+{
+  if (m_mprisServiceName.isEmpty())
+    return;
+
+  if (QDBusConnection::sessionBus().isConnected()) {
+    QDBusConnection::sessionBus().unregisterObject(
+          QLatin1String("/org/mpris/MediaPlayer2"));
+    if (QDBusConnection::sessionBus().unregisterService(m_mprisServiceName)) {
+      m_mprisServiceName.clear();
+    } else {
+      qWarning("Unregistering D-Bus MPRIS service failed");
+    }
+  } else {
+    qWarning("Cannot connect to the D-BUS session bus.");
+  }
+}
+#endif
 #endif
 
 /**

src/core/model/kid3application.h

@@ -1060,6 +1060,18 @@ public slots:
    * Show play tool bar.
    */
   void showAudioPlayer();
+
+#ifdef HAVE_QTDBUS
+  /**
+   * Activate the MPRIS D-Bus Interface if not already active.
+   */
+  void activateMprisInterface();
+
+  /**
+   * Deactivate the MPRIS D-Bus Interface if it is active.
+   */
+  void deactivateMprisInterface();
+#endif
 #endif
 
   /**
@@ -1322,6 +1334,9 @@ private:
 #if defined HAVE_PHONON || QT_VERSION >= 0x050000
   /** Audio player */
   AudioPlayer* m_player;
+#ifdef HAVE_QTDBUS
+  QString m_mprisServiceName;
+#endif
 #endif
   FileFilter* m_expressionFileFilter;
   /** Information about selected tagged files */

src/core/model/mprisinterface.cpp

+/**
+ * \file mprisinterface.cpp
+ * MPRIS D-Bus interface for audio player.
+ *
+ * \b Project: Kid3
+ * \author Urs Fleisch
+ * \date 09-Dec-2016
+ *
+ * Copyright (C) 2016  Urs Fleisch
+ *
+ * This file is part of Kid3.
+ *
+ * Kid3 is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Kid3 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "mprisinterface.h"
+
+#if (defined HAVE_PHONON || QT_VERSION >= 0x050000) && defined HAVE_QTDBUS
+
+#include <QDBusMessage>
+#include <QDBusConnection>
+#include <QDBusObjectPath>
+#include <QUrl>
+#include <QDir>
+#include <QTemporaryFile>
+#include <QApplication>
+#include "audioplayer.h"
+#include "taggedfile.h"
+#include "trackdata.h"
+#include "pictureframe.h"
+
+MprisInterface::MprisInterface(AudioPlayer* player)
+  : QDBusAbstractAdaptor(player), m_audioPlayer(player)
+{
+}
+
+MprisInterface::~MprisInterface()
+{
+}
+
+QString MprisInterface::identity() const
+{
+  return QLatin1String("Kid3");
+}
+
+QString MprisInterface::desktopEntry() const
+{
+  // Organization domain is only set in the KDE application.
+  return QApplication::organizationDomain().isEmpty()
+      ? QLatin1String("kid3-qt") : QLatin1String("kid3");
+}
+
+QStringList MprisInterface::supportedUriSchemes() const
+{
+  return QStringList() << QLatin1String("file");
+}
+
+QStringList MprisInterface::supportedMimeTypes() const
+{
+  return QStringList()
+      << QLatin1String("audio/mpeg")
+      << QLatin1String("audio/ogg")
+      << QLatin1String("application/ogg")
+      << QLatin1String("audio/x-flac")
+      << QLatin1String("audio/x-flac+ogg")
+      << QLatin1String("audio/x-vorbis+ogg")
+      << QLatin1String("audio/x-speex+ogg")
+      << QLatin1String("audio/x-oggflac")
+      << QLatin1String("audio/x-musepack")
+      << QLatin1String("audio/aac")
+      << QLatin1String("audio/mp4")
+      << QLatin1String("audio/x-speex")
+      << QLatin1String("audio/x-tta")
+      << QLatin1String("audio/x-wavpack")
+      << QLatin1String("audio/x-aiff")
+      << QLatin1String("audio/x-it")