Blimp Settings framework on the c++ side

blimp/client/core/settings/settings.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 BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_H_
+#define BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_H_
+
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "components/prefs/command_line_pref_store.h"
+#include "components/prefs/pref_change_registrar.h"
+#include "components/prefs/pref_observer.h"
+#include "components/prefs/pref_service.h"
+
+class CommandLinePrefStore;
+class PrefRegistrySimple;
+
+namespace blimp {
+namespace client {
+
+class SettingsObserver;
+
+class Settings : public PrefObserver {
+ public:
+  explicit Settings(PrefService* local_state);
+  virtual ~Settings();
+
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+  static void ApplyBlimpSwitches(CommandLinePrefStore* store);
+
+  void AddObserver(SettingsObserver* observer);
+  void RemoveObserver(SettingsObserver* observer);
+
+  // Set whether or not Blimp mode is enabled.
+  void SetEnableBlimpMode(bool enable);
+
+  // Set record_whole_document_, and save it to the persistent storage.
+  void SetRecordWholeDocument(bool enable);
+
+  // Set show_network_stats_.
+  void SetShowNetworkStats(bool enable);
+
+  // PrefObserver implementation.
+  void OnPreferenceChanged(PrefService* service,
+                           const std::string& pref_name) override;
+
+  // Whether or not Blimp mode is enabled.
+  // Can be changed via: command line --enable-blimp, setting dialog.
+  // Persisted across restarts: Yes.
+  bool IsBlimpEnabled();
+
+  // Whether or not the engine sends the whole webpage at once or pieces of it
+  // based on the current viewport.
+  // Can be changed via: command line --download-whole-document, setting dialog.
+  // Persisted across restarts: Yes.
+  bool IsRecordWholeDocument();
+
+  // Whether or not to show the network stats.
+  // Can be changed via: setting dialog.
+  // Persisted across restarts: No.
+  bool show_network_stats() { return show_network_stats_; }
+
+ private:
+  // The pref service used to store the persistent settings.
+  PrefService* local_state_;
+
+  PrefChangeRegistrar pref_change_registrar_;
+
+  // A list of all the observers of the Blimp Settings.
+  base::ObserverList<SettingsObserver> observers_;
+
+  bool show_network_stats_;
+
+  DISALLOW_COPY_AND_ASSIGN(Settings);
+};
+
+}  // namespace client
+}  // namespace blimp
+
+#endif  // BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_H_