Implement chrome.brailleDisplayPrivate API

chrome/browser/extensions/api/braille_display_private/braille_controller.h

+// 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.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_API_BRAILLE_DISPLAY_PRIVATE_BRAILLE_CONTROLLER_H_
+
+#define CHROME_BROWSER_EXTENSIONS_API_BRAILLE_DISPLAY_PRIVATE_BRAILLE_CONTROLLER_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/values.h"
+#include "chrome/common/extensions/api/braille_display_private.h"
+
+namespace extensions {
+namespace api {
+namespace braille_display_private {
+class BrailleObserver;
+
+#ifdef USE_BRLAPI
+class BrlapiConnection;
+#endif  // USE_BRLAPI
+
+// Singleton class that controls the braille display.
+class BrailleController {
+ public:
+  static BrailleController* GetInstance();
+
+#ifdef USE_BRLAPI
+  typedef base::Callback<scoped_ptr<BrlapiConnection>()>
+      CreateBrlapiConnectionFunction;
+  // For dependency injection in tests.  Sets the function used to create
+  // brlapi connections.
+  virtual void SetCreateBrlapiConnectionForTesting(
+      const CreateBrlapiConnectionFunction& callback) = 0;
+#endif  // USE_BRLAPI
+
+  virtual scoped_ptr<base::DictionaryValue> GetDisplayState() = 0;
+  virtual void WriteDots(const std::string& cells) = 0;
+  virtual void AddObserver(BrailleObserver* observer) = 0;
+  virtual void RemoveObserver(BrailleObserver* observer) = 0;
+
+ protected:
+  BrailleController();
+  virtual ~BrailleController();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BrailleController);
+};
+
+// Observer for events from the BrailleController
+class BrailleObserver {
+ public:
+  virtual void OnKeyEvent(
+      const extensions::api::braille_display_private::KeyEvent &event) {}
+};
+
+}  // namespace braille_display_private
+}  // namespace api
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_API_BRAILLE_DISPLAY_PRIVATE_BRAILLE_CONTROLLER_H_