// Copyright (c) 2012 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.
//
// A fake implementation of AudioInputStream, useful for testing purpose.

#ifndef MEDIA_AUDIO_FAKE_AUDIO_INPUT_STREAM_H_
#define MEDIA_AUDIO_FAKE_AUDIO_INPUT_STREAM_H_

#include <vector>

#include "base/callback_forward.h"
#include "base/memory/scoped_ptr.h"
#include "media/audio/audio_io.h"
#include "media/audio/audio_parameters.h"
#include "media/audio/fake_audio_worker.h"


namespace media {

class AudioBus;
class AudioManagerBase;
class SimpleSource;

// This class acts as a fake audio input stream. The default is to generate a
// beeping sound unless --use-file-for-fake-audio-capture=<file> is specified,
// in which case the indicated .wav file will be read and played into the
// stream.
class MEDIA_EXPORT FakeAudioInputStream
    : public AudioInputStream {
 public:
  static AudioInputStream* MakeFakeStream(
      AudioManagerBase* manager, const AudioParameters& params);

  bool Open() override;
  void Start(AudioInputCallback* callback) override;
  void Stop() override;
  void Close() override;
  double GetMaxVolume() override;
  void SetVolume(double volume) override;
  double GetVolume() override;
  bool IsMuted() override;
  bool SetAutomaticGainControl(bool enabled) override;
  bool GetAutomaticGainControl() override;

  // Generate one beep sound. This method is called by FakeVideoCaptureDevice to
  // test audio/video synchronization. This is a static method because
  // FakeVideoCaptureDevice is disconnected from an audio device. This means
  // only one instance of this class gets to respond, which is okay because we
  // assume there's only one stream for this testing purpose. Furthermore this
  // method will do nothing if --use-file-for-fake-audio-capture is specified
  // since the input stream will be playing from a file instead of beeping.
  // TODO(hclam): Make this non-static. To do this we'll need to fix
  // crbug.com/159053 such that video capture device is aware of audio
  // input stream.
  static void BeepOnce();

 private:
  FakeAudioInputStream(AudioManagerBase* manager,
                       const AudioParameters& params);
  ~FakeAudioInputStream() override;

  scoped_ptr<AudioOutputStream::AudioSourceCallback> ChooseSource();
  void ReadAudioFromSource();

  AudioManagerBase* audio_manager_;
  AudioInputCallback* callback_;
  FakeAudioWorker fake_audio_worker_;
  AudioParameters params_;

  scoped_ptr<AudioOutputStream::AudioSourceCallback> audio_source_;
  scoped_ptr<media::AudioBus> audio_bus_;

  DISALLOW_COPY_AND_ASSIGN(FakeAudioInputStream);
};

}  // namespace media

#endif  // MEDIA_AUDIO_FAKE_AUDIO_INPUT_STREAM_H_