/**
  * @RDE_HEADER@
  * ICommand
  * $Id$
  * $HeadURL$
  * $Author$
  * Created by Christian Fröbel, SLSE, 2017-06-29
  */

#pragma once

#include <AudioVideoManagement/avm_export.h>
#include <QObject>

namespace AudioVideoManagement
{

/**
 * Internal helper class for AvaControl in order to send a command to the
 * AVS system and synchronize with the reponse.
 * This way AvaControl ensures that a new command is only sent when the
 * response of the previous command has been received.
 *
 * The idea is that upon send() the command connects to the signals of interest
 * of AvaComm. When the command is done it calls AvaControl::done(this).
 *
 * @author Christian Fröbel
 */
class AVM_COMMON_EXPORT ICommand : public QObject
{
  Q_OBJECT

public:
  virtual ~ICommand() = default;

  virtual void send() = 0;

  virtual QString debug() const = 0;

  virtual bool canTimeout() const { return false; }

  /**
   * Check whether this command nullifies other.
   * Nullifying means that when this command is sent after other,
   * it would nullify the effect of other.
   * If so, other can be dropped.
   */
  virtual bool nullifies(ICommand *other) const { Q_UNUSED(other); return false; }
};

} // namespace AudioVideoManagement