qt-everywhere-src-5.15.1/qtwebengine/src/3rdparty/chromium/media/audio/win/audio_session_event_listener_win.h

// Copyright 2019 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_AUDIO_WIN_AUDIO_SESSION_EVENT_LISTENER_WIN_H_
#define MEDIA_AUDIO_WIN_AUDIO_SESSION_EVENT_LISTENER_WIN_H_

#include <audiopolicy.h>
#include <wrl/client.h>

#include "base/callback.h"
#include "media/base/media_export.h"

namespace media {

class MEDIA_EXPORT AudioSessionEventListener : public IAudioSessionEvents {
 public:
  // Calls RegisterAudioSessionNotification() on |client| and calls
  // |device_change_cb| when OnSessionDisconnected() is called.
  //
  // Since the IAudioClient session is dead after the disconnection, we use a
  // OnceCallback. The delivery of this notification is fatal to the |client|.
  AudioSessionEventListener(IAudioClient* client,
                            base::OnceClosure device_change_cb);
  virtual ~AudioSessionEventListener();

 private:
  friend class AudioSessionEventListenerTest;

  STDMETHOD_(ULONG, AddRef)() override;
  STDMETHOD_(ULONG, Release)() override;
  STDMETHOD(QueryInterface)(REFIID iid, void** object) override;

  // IAudioSessionEvents implementation.
  STDMETHOD(OnChannelVolumeChanged)
  (DWORD channel_count,
   float new_channel_volume_array[],
   DWORD changed_channel,
   LPCGUID event_context) override;
  STDMETHOD(OnDisplayNameChanged)
  (LPCWSTR new_display_name, LPCGUID event_context) override;
  STDMETHOD(OnGroupingParamChanged)
  (LPCGUID new_grouping_param, LPCGUID event_context) override;
  STDMETHOD(OnIconPathChanged)
  (LPCWSTR new_icon_path, LPCGUID event_context) override;
  STDMETHOD(OnSessionDisconnected)
  (AudioSessionDisconnectReason disconnect_reason) override;
  STDMETHOD(OnSimpleVolumeChanged)
  (float new_volume, BOOL new_mute, LPCGUID event_context) override;
  STDMETHOD(OnStateChanged)(AudioSessionState new_state) override;

  base::OnceClosure device_change_cb_;
  Microsoft::WRL::ComPtr<IAudioSessionControl> audio_session_control_;
};

}  // namespace media

#endif  // MEDIA_AUDIO_WIN_AUDIO_SESSION_EVENT_LISTENER_WIN_H_