/**
  * @RDE_HEADER@
  * PlaybackApp
  * $Id$
  * $HeadURL$
  * $Author$
  * Created by Christian Fröbel, NLSE, 2018-04-18
  */

#pragma once

#include <Plugins/AudioVideoManagement/Shared/avmshared_export.h>
#include <QString>
#include <QObject>
#include <memory>
#include <functional>

class QRect;

namespace AudioVideoManagement
{

class AvsApp;
class AvaControl;

// PlaybackApp cannot be a QObject, so we need a wrapper that takes signals, etc.
class AVMSHARED_EXPORT ObjectWrapper : public QObject
{
  Q_OBJECT
public:
  ObjectWrapper(QObject *parent) : QObject(parent) {}

signals:
  void signalVisible();
  void signalPause();
  void signalResume();
};


/**
 * Represents a playback application -- either for video or for audio.
 * Audio does not require the AVS dialog to be visible and we don't need
 * a separate application in the Excon-sense for that. Use AppType::AlwaysHidden
 * for audio.
 *
 * The Video PlaybackApp will cover a whole screen as all the other Excon apps do
 * and will be placed in the same way (see AvsApp).
 *
 * PlaybackApp is a resource and can only be used by one client at the same time.
 *
 * @author Christian Fröbel
 */
class AVMSHARED_EXPORT PlaybackApp
{
public:

  enum class AppType
  {
    Normal = 1,   //!< Visible AVS-dialog, no auto-hide on release()
    AutoHide,     //!< Visible AVS-dialog, auto-hide on release()
    AlwaysHidden  //!< No visible AVS-dialog (for audio playback)
  };

  /**
   * Use AppType::AlwaysHidden for Audio.
   */
  PlaybackApp(const QString &dialogId, AvaControl *avaControl, AppType);
  virtual ~PlaybackApp();

  ObjectWrapper *objectWrapper() { return m_objectWrapper; }
  const QString &dialogId() const { return m_dialogId; }

  /** @return true if someone is using this App. */
  bool inUse() const { return m_inUse; }

  /**
   * Resource acquisition.
   * Don't use directly; use PlaybackAppHandle instead.
   */
  ///@{
  /**
   * May only be called when inUse() == false.
   * Will implicitly show the underlying AvsApp.
   */
  void acquire();
  void acquire(const QRect &geometry);
  void setGeometry(const QRect &geometry);
  /**
   * Will implicitly hide the underlying AvsApp when appType == AppType::AutoHide.
   */
  void release();

  void hide(bool andClose);

  ///@}

private:
  const QString             m_dialogId;
  bool                      m_inUse{false};
  bool                      m_autoHide;
  std::unique_ptr<AvsApp>   m_app; //!< only set when appType != AppType::AlwaysHidden
  ObjectWrapper *m_objectWrapper { nullptr };
};


/**
 * @author Christian Fröbel
 */
class AVMSHARED_EXPORT PlaybackAppHandle
{
public:
  PlaybackAppHandle() = default;
  explicit PlaybackAppHandle(PlaybackApp *app);
  PlaybackAppHandle(PlaybackApp *app, const QRect &geometry);

  operator bool() const { return m_app.get() != nullptr; }

  const QString &dialogId() const { return m_app->dialogId(); }
  void hide(bool andClose = false) { m_app->hide(andClose); }
  ObjectWrapper *objectWrapper() { return m_app->objectWrapper(); }

private:
  using Releaser = std::function<void (PlaybackApp *)>;
  std::unique_ptr<PlaybackApp, Releaser>   m_app;
};

} // namespace AudioVideoManagement