blob: 38fc76686bc627a8608e29d262719d0598731cc3 [file] [log] [blame]
// Copyright 2017 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 <memory>
#include "base/callback.h"
#include "base/files/file_path.h"
#include "base/memory/scoped_refptr.h"
#include "base/threading/thread.h"
#include "base/values.h"
namespace base {
class FilePathWatcher;
class SequencedTaskRunner;
} // namespace base
namespace chromecast {
namespace media {
class CastAudioJson {
// Returns GetFilePathForTuning() if a file exists at that path, otherwise
// returns GetReadOnlyFilePath().
static base::FilePath GetFilePath();
static base::FilePath GetReadOnlyFilePath();
static base::FilePath GetFilePathForTuning();
// Provides an interface for reading CastAudioJson and registering for file
// updates.
class CastAudioJsonProvider {
using TuningChangedCallback =
base::RepeatingCallback<void(std::unique_ptr<base::Value> contents)>;
virtual ~CastAudioJsonProvider() = default;
// Returns the contents of cast_audio.json.
// If a file exists at CastAudioJson::GetFilePathForTuning() and is valid
// JSON, its contents will be returned. Otherwise, the contents of the file
// at CastAudioJson::GetReadOnlyFilePath() will be returned.
// This function will run on the thread on which it is called, and may
// perform blocking I/O.
virtual std::unique_ptr<base::Value> GetCastAudioConfig() = 0;
// |callback| will be called when a new cast_audio config is available.
// |callback| will always be called from the same thread, but not the same
// thread on which |SetTuningChangedCallback| is called.
// |callback| will never be called after ~CastAudioJsonProvider() is called.
virtual void SetTuningChangedCallback(TuningChangedCallback callback) = 0;
class CastAudioJsonProviderImpl : public CastAudioJsonProvider {
~CastAudioJsonProviderImpl() override;
// CastAudioJsonProvider implementation:
std::unique_ptr<base::Value> GetCastAudioConfig() override;
void SetTuningChangedCallback(TuningChangedCallback callback) override;
void StopWatchingFileOnThread();
void OnTuningFileChanged(const base::FilePath& path, bool error);
TuningChangedCallback callback_;
base::Thread thread_;
scoped_refptr<base::SequencedTaskRunner> task_runner_;
std::unique_ptr<base::FilePathWatcher> cast_audio_watcher_;
} // namespace media
} // namespace chromecast