Add the copresence component.

components/copresence/public/whispernet_client.h

+// Copyright 2014 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 COMPONENTS_COPRESENCE_INTERFACE_WHISPERNET_CLIENT_H_
+#define COMPONENTS_COPRESENCE_INTERFACE_WHISPERNET_CLIENT_H_
+
+#include <string>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace media {
+class AudioBusRefCounted;
+}
+
+namespace copresence {
+
+// The interface that the whispernet client needs to implement. These methods
+// provide us the ability to use the audio medium in copresence. Currently since
+// the only medium that copresence uses is audio, the implementation of this
+// interface is required.
+class WhispernetClient {
+ public:
+  // Generic callback to indicate a boolean success or failure.
+  typedef base::Callback<void(bool)> SuccessCallback;
+  // Callback that returns detected tokens.
+  typedef base::Callback<void(const std::vector<std::string>&)> TokensCallback;
+  // Callback that returns encoded samples for a given token.
+  typedef base::Callback<
+      void(const std::string&, const scoped_refptr<media::AudioBusRefCounted>&)>
+      SamplesCallback;
+
+  // Initialize the whispernet client and call the callback when done. The
+  // parameter indicates whether we succeeded or failed.
+  virtual void Initialize(const SuccessCallback& init_callback) = 0;
+  // Copresence will call this before making any calls to its destructors.
+  virtual void Shutdown() = 0;
+
+  // Fires an event to request a token encode.
+  virtual void EncodeToken(const std::string& token) = 0;
+  // Fires an event to request a decode for the given samples.
+  virtual void DecodeSamples(const std::string& samples) = 0;
+  // Fires an event to request detection of a whispernet broadcast.
+  virtual void DetectBroadcast() = 0;
+
+  // Callback registreation methods. These are the callbacks that will be
+  // registered by Copresence to receive data.
+  virtual void RegisterTokensCallback(
+      const TokensCallback& tokens_callback) = 0;
+  virtual void RegisterSamplesCallback(
+      const SamplesCallback& samples_callback) = 0;
+  virtual void RegisterDetectBroadcastCallback(
+      const SuccessCallback& db_callback) = 0;
+
+  // Don't cache these callbacks, as they may become invalid at any time.
+  // Always invoke callbacks directly through these accessors.
+  virtual TokensCallback GetTokensCallback() = 0;
+  virtual SamplesCallback GetSamplesCallback() = 0;
+  virtual SuccessCallback GetDetectBroadcastCallback() = 0;
+  virtual SuccessCallback GetInitializedCallback() = 0;
+
+  virtual ~WhispernetClient() {};
+};
+
+}  // namespace copresence
+
+#endif  // COMPONENTS_COPRESENCE_INTERFACE_WHISPERNET_CLIENT_H_