Move PW message handler logic to components

components/physical_web/webui/physical_web_base_message_handler.h

+// Copyright 2016 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_PHYSICAL_WEB_WEBUI_PHYSICAL_WEB_BASE_MESSAGE_HANDLER_H_
+#define COMPONENTS_PHYSICAL_WEB_WEBUI_PHYSICAL_WEB_BASE_MESSAGE_HANDLER_H_
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/values.h"
+
+namespace physical_web {
+
+class PhysicalWebDataSource;
+
+}  // namespace physical_web
+
+namespace physical_web_ui {
+
+// This is the equivalent of content::WebUI::MessageCallback.
+typedef base::Callback<void(const base::ListValue*)> MessageCallback;
+
+// The base handler for Javascript messages for the chrome://physical-web page.
+// This does not implement WebUIMessageHandler or register its methods.
+class PhysicalWebBaseMessageHandler {
+ public:
+  PhysicalWebBaseMessageHandler();
+  virtual ~PhysicalWebBaseMessageHandler();
+
+  // Handles the RequestNearbyURLs message, returning URLs that are currently
+  // being broadcasted by Physical Web transports.
+  void HandleRequestNearbyURLs(const base::ListValue* args);
+
+  // Handles a click on a Physical Web URL, recording the click and
+  // directing the user appropriately.
+  void HandlePhysicalWebItemClicked(const base::ListValue* args);
+
+  // Registers the messages that this MessageHandler can handle.
+  void RegisterMessages();
+
+ protected:
+  // Subclasses should implement these protected methods as a pass through to
+  // the similarly named methods of the appropriate WebUI object (the exact
+  // WebUI class differs per platform).
+  virtual void RegisterMessageCallback(
+      const std::string& message,
+      const MessageCallback& callback) = 0;
+  virtual void CallJavaScriptFunction(const std::string& function,
+                                      const base::Value& arg) = 0;
+  virtual physical_web::PhysicalWebDataSource* GetPhysicalWebDataSource() = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(PhysicalWebBaseMessageHandler);
+};
+
+}  // namespace physical_web_ui
+
+#endif  // COMPONENTS_PHYSICAL_WEB_WEBUI_PHYSICAL_WEB_BASE_MESSAGE_HANDLER_H_