Clementine-audio-player-Mac-Linux-Windows/src/moodbar/moodbarpipeline.h

/* This file is part of Clementine.
   Copyright 2012, David Sansome <me@davidsansome.com>

   Clementine 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 3 of the License, or
   (at your option) any later version.

   Clementine 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 Clementine.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef MOODBARPIPELINE_H
#define MOODBARPIPELINE_H

#include <QObject>
#include <QUrl>

#include <gst/gst.h>
#include <gst/app/gstappsink.h>

// Creates moodbar data for a single local music file.
class MoodbarPipeline : public QObject {
  Q_OBJECT

public:
  MoodbarPipeline(const QUrl& local_filename);
  ~MoodbarPipeline();

  static bool IsAvailable();

  bool success() const { return success_; }
  const QByteArray& data() const { return data_; }

public slots:
  void Start();

signals:
  void Finished(bool success);

private:
  GstElement* CreateElement(const QString& factory_name);

  void ReportError(GstMessage* message);
  void Stop(bool success);
  void Cleanup();

  static void NewPadCallback(GstElement*, GstPad* pad, gpointer data);
  static GstFlowReturn NewBufferCallback(GstAppSink* app_sink, gpointer self);
  static gboolean BusCallback(GstBus*, GstMessage* msg, gpointer data);
  static GstBusSyncReply BusCallbackSync(GstBus*, GstMessage* msg, gpointer data);

private:
  static bool sIsAvailable;

  QUrl local_filename_;
  GstElement* pipeline_;
  GstElement* convert_element_;

  bool success_;
  QByteArray data_;
};

#endif // MOODBARPIPELINE_H