Blimp Settings framework on the c++ side

blimp/client/core/settings/settings.cc

Index: blimp/client/core/settings/settings.cc
diff --git a/blimp/client/core/settings/settings.cc b/blimp/client/core/settings/settings.cc
new file mode 100644
index 0000000000000000000000000000000000000000..00cfe884885bcb5ed655f1f1fa07ea75d97937f0
--- /dev/null
+++ b/blimp/client/core/settings/settings.cc
@@ -0,0 +1,94 @@
+// 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.
+
+#include "blimp/client/core/settings/settings.h"
+
+#include "base/bind.h"
+#include "base/command_line.h"
+#include "blimp/client/core/settings/settings_observer.h"
+#include "blimp/client/core/switches/blimp_client_switches.h"
+#include "components/prefs/pref_registry_simple.h"
+
+namespace blimp {
+namespace client {
+
+const CommandLinePrefStore::BooleanSwitchToPreferenceMapEntry
+    Settings::boolean_switch_map_[] = {
+        {blimp::switches::kEnableBlimp, prefs::kBlimpEnabled, true},
+        {blimp::switches::kDownloadWholeDocument,
+         prefs::kRecordWholeDocument, true},
+};
+
+Settings::Settings(PrefService* local_state)
+    : local_state_(local_state),
+      show_network_stats_(false) {
+  pref_change_registrar_.Init(local_state);
+  pref_change_registrar_.Add(
+      prefs::kBlimpEnabled,
+      base::Bind(&Settings::OnPreferenceChanged, base::Unretained(this),
+                 local_state, prefs::kBlimpEnabled));
+  pref_change_registrar_.Add(
+      prefs::kRecordWholeDocument,
+      base::Bind(&Settings::OnPreferenceChanged, base::Unretained(this),
+                 local_state, prefs::kRecordWholeDocument));
+}
+
+Settings::~Settings() = default;
+
+void Settings::AddObserver(SettingsObserver* observer) {
+  observers_.AddObserver(observer);
+}
+
+void Settings::RemoveObserver(SettingsObserver* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+void Settings::SetShowNetworkStats(bool enable) {
+  if (show_network_stats_ == enable)
+    return;
+
+  show_network_stats_ = enable;
+  for (auto& observer : observers_) {
+    observer.OnShowNetworkStatsChanged(show_network_stats_);

[Bernhard Bauer, 2016/10/25 14:30:50]

Nit: For the if-statement above, you leave out braces for the body. I'm not sure
if Blimp code has a particular preference one way or another, but staying
consistent would be good.

[Menglin, 2016/10/25 18:32:52]

Done.

+  }
+}
+
+void Settings::SetEnableBlimpMode(bool enable) {
+  local_state_->SetBoolean(prefs::kBlimpEnabled, enable);
+}
+
+void Settings::SetRecordWholeDocument(bool enable) {
+  local_state_->SetBoolean(prefs::kRecordWholeDocument, enable);
+}
+
+void Settings::OnPreferenceChanged(
+    PrefService* service, const std::string& pref_name) {
+  if (pref_name == prefs::kBlimpEnabled) {
+    for (auto& observer : observers_) {
+      observer.OnBlimpModeEnabled(service->GetBoolean(pref_name));
+    }
+    for (auto& observer : observers_) {

[Bernhard Bauer, 2016/10/25 14:30:50]

Is it intentional that this will iterate over all observers twice rather than
doing it once and calling both methods?

[Menglin, 2016/10/25 18:32:52]

should do it once and call both methods. I was just mechanically switching from
FOR_EACH_OBSERVER to the for (auto& observer : observers_) format :(

+      observer.OnRestartRequired();
+    }
+  } else if (pref_name == prefs::kRecordWholeDocument) {
+    for (auto& observer : observers_) {
+      observer.OnRecordWholeDocumentChanged(service->GetBoolean(pref_name));
+    }
+  }
+}
+
+// static
+void Settings::RegisterPrefs(PrefRegistrySimple* registry) {
+  registry->RegisterBooleanPref(prefs::kBlimpEnabled, false);
+  registry->RegisterBooleanPref(prefs::kRecordWholeDocument, false);
+}
+
+// static
+void Settings::ApplyBlimpSwitches(CommandLinePrefStore* store) {
+  store->ApplyBooleanSwitches(boolean_switch_map_,
+                              arraysize(boolean_switch_map_));
+}
+
+}  // namespace client
+}  // namespace blimp