blob: 8c4c3c5af0c8277c7bdcb6fd9740a6d928409c3d [file] [log] [blame]
// Copyright (c) 2013 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.
#include "base/component_export.h"
#include "base/memory/ref_counted.h"
#include "chromeos/audio/audio_pref_observer.h"
namespace chromeos {
struct AudioDevice;
// Interface that handles audio preference related work, reads and writes
// audio preferences, and notifies AudioPrefObserver for audio preference
// changes.
: public base::RefCountedThreadSafe<AudioDevicesPrefHandler> {
// Integer because C++ does not allow static const double in header files.
static const int kDefaultOutputVolumePercent = 75;
static const int kDefaultHdmiOutputVolumePercent = 100;
// Gets the audio output volume value from prefs for a device. Since we can
// only have either a gain or a volume for a device (depending on whether it
// is input or output), we don't really care which value it is.
virtual double GetOutputVolumeValue(const AudioDevice* device) = 0;
virtual double GetInputGainValue(const AudioDevice* device) = 0;
// Sets the audio volume or gain value to prefs for a device.
virtual void SetVolumeGainValue(const AudioDevice& device, double value) = 0;
// Reads the audio mute value from prefs for a device.
virtual bool GetMuteValue(const AudioDevice& device) = 0;
// Sets the audio mute value to prefs for a device.
virtual void SetMuteValue(const AudioDevice& device, bool mute_on) = 0;
// Sets the device active state in prefs.
// Note: |activate_by_user| indicates whether |device| is set to active
// by user or by priority, and it only matters when |active| is true.
virtual void SetDeviceActive(const AudioDevice& device,
bool active,
bool activate_by_user) = 0;
// Returns false if it fails to get device active state from prefs.
// Otherwise, returns true, pass the active state data in |*active|
// and |*activate_by_user|.
// Note: |*activate_by_user| only matters when |*active| is true.
virtual bool GetDeviceActive(const AudioDevice& device,
bool* active,
bool* activate_by_user) = 0;
// Reads the audio output allowed value from prefs.
virtual bool GetAudioOutputAllowedValue() = 0;
// Adds an audio preference observer.
virtual void AddAudioPrefObserver(AudioPrefObserver* observer) = 0;
// Removes an audio preference observer.
virtual void RemoveAudioPrefObserver(AudioPrefObserver* observer) = 0;
virtual ~AudioDevicesPrefHandler() {}
friend class base::RefCountedThreadSafe<AudioDevicesPrefHandler>;
} // namespace chromeos