strawberry-audio-player-windows-mac-linux/src/moodbar/moodbarpipeline.h

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

   Strawberry 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.

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

#ifndef MOODBARPIPELINE_H
#define MOODBARPIPELINE_H

#include <QObject>
#include <QByteArray>
#include <QString>
#include <QUrl>

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

#include <memory>

class MoodbarBuilder;

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

 public:
  explicit MoodbarPipeline(const QUrl &local_filename, QObject *parent = nullptr);
  ~MoodbarPipeline() override;

  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 *msg);
  void Stop(const 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 const int kBands;

  QUrl local_filename_;
  GstElement *pipeline_;
  GstElement *convert_element_;

  std::unique_ptr<MoodbarBuilder> builder_;

  bool success_;
  bool running_;
  QByteArray data_;
};

#endif  // MOODBARPIPELINE_H