Implemented types.private.ChromeDirectSetting.onChange

chrome/browser/extensions/api/preference/chrome_direct_setting_api.cc

+// 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.
+
+#include "chrome/browser/extensions/api/preference/chrome_direct_setting_api.h"
+
+#include "base/bind.h"
+#include "base/containers/hash_tables.h"
+#include "base/lazy_instance.h"
+#include "base/prefs/pref_change_registrar.h"
+#include "base/prefs/pref_service.h"
+#include "base/strings/stringprintf.h"
+#include "chrome/browser/extensions/api/preference/preference_api_constants.h"
+#include "chrome/browser/extensions/extension_service.h"
+#include "chrome/browser/profiles/profile.h"
+
+namespace extensions {
+namespace chromedirectsetting {
+
+const char kOnPrefChangeFormat[] =
+    "types.private.ChromeDirectSetting.%s.onChange";
+
+class PreferenceWhitelist {
+ public:
+  PreferenceWhitelist() {
+    whitelist_.insert("googlegeolocationaccess.enabled");
+  }
+
+  ~PreferenceWhitelist() {}
+
+  bool IsPreferenceOnWhitelist(const std::string& pref_key){
+    return whitelist_.find(pref_key) != whitelist_.end();
+  }
+
+  void RegisterEventListeners(
+      Profile* profile,
+      EventRouter::Observer* observer) {
+    for (base::hash_set<std::string>::iterator iter = whitelist_.begin();
+         iter != whitelist_.end();
+         iter++) {
+      std::string event_name = base::StringPrintf(
+          kOnPrefChangeFormat,
+          (*iter).c_str());
+      ExtensionSystem::Get(profile)->event_router()->RegisterObserver(
+          observer,
+          event_name);
+    }
+  }
+
+  void RegisterPropertyListeners(
+      Profile* profile,
+      PrefChangeRegistrar* registrar,
+      const base::Callback<void(const std::string&)>& callback) {
+    for (base::hash_set<std::string>::iterator iter = whitelist_.begin();
+         iter != whitelist_.end();
+         iter++) {
+      const char* pref_key = (*iter).c_str();
+      std::string event_name = base::StringPrintf(
+          kOnPrefChangeFormat,
+          pref_key);
+      registrar->Add(pref_key, callback);
+    }
+  }
+
+ private:
+  base::hash_set<std::string> whitelist_;
+
+  DISALLOW_COPY_AND_ASSIGN(PreferenceWhitelist);
+};
+
+base::LazyInstance<PreferenceWhitelist> preference_whitelist =
+    LAZY_INSTANCE_INITIALIZER;
+
+static base::LazyInstance<ProfileKeyedAPIFactory<ChromeDirectSettingAPI> >
+    g_factory = LAZY_INSTANCE_INITIALIZER;
+
+ChromeDirectSettingAPI::ChromeDirectSettingAPI(Profile* profile)
+    : profile_(profile) {
+  preference_whitelist.Get().RegisterEventListeners(profile, this);
+}
+
+ChromeDirectSettingAPI::~ChromeDirectSettingAPI() {}
+
+// BrowserContextKeyedService implementation.
+void ChromeDirectSettingAPI::Shutdown() {}
+
+// ProfileKeyedAPI implementation.
+ProfileKeyedAPIFactory<ChromeDirectSettingAPI>*
+    ChromeDirectSettingAPI::GetFactoryInstance() {
+  return &g_factory.Get();
+}
+
+// EventRouter::Observer implementation.
+void ChromeDirectSettingAPI::OnListenerAdded(const EventListenerInfo& details) {
+  ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
+  registrar_.Init(profile_->GetPrefs());
+  preference_whitelist.Get().RegisterPropertyListeners(
+      profile_,
+      &registrar_,
+      base::Bind(&ChromeDirectSettingAPI::OnPrefChanged,
+                 base::Unretained(this),
+                 registrar_.prefs()));
+}
+
+bool ChromeDirectSettingAPI::IsPreferenceOnWhitelist(
+    const std::string& pref_key) {
+  return preference_whitelist.Get().IsPreferenceOnWhitelist(pref_key);
+}
+
+ChromeDirectSettingAPI* ChromeDirectSettingAPI::Get(Profile* profile) {
+  return
+      ProfileKeyedAPIFactory<ChromeDirectSettingAPI>::GetForProfile(profile);
+}
+
+// ProfileKeyedAPI implementation.
+const char* ChromeDirectSettingAPI::service_name() {
+  return "ChromeDirectSettingAPI";
+}
+
+void ChromeDirectSettingAPI::OnPrefChanged(
+    PrefService* pref_service, const std::string& pref_key) {
+  std::string event_name = base::StringPrintf(kOnPrefChangeFormat,
+                                              pref_key.c_str());
+  EventRouter* router = ExtensionSystem::Get(profile_)->event_router();
+  if (router && router->HasEventListener(event_name)) {
+    const PrefService::Preference* preference =
+        profile_->GetPrefs()->FindPreference(pref_key.c_str());
+    const base::Value* value = preference->GetValue();
+
+    scoped_ptr<DictionaryValue> result(new DictionaryValue);
+    result->Set(preference_api_constants::kValue, value->DeepCopy());
+    base::ListValue args;
+    args.Append(result.release());
+
+    ExtensionService* extension_service =
+        ExtensionSystem::Get(profile_)->extension_service();
+    const ExtensionSet* extensions = extension_service->extensions();
+    for (ExtensionSet::const_iterator it = extensions->begin();
+         it != extensions->end(); ++it) {
+      if ((*it)->location() == Manifest::COMPONENT) {
+        std::string extension_id = (*it)->id();
+        if (router->ExtensionHasEventListener(extension_id, event_name)) {
+          scoped_ptr<base::ListValue> args_copy(args.DeepCopy());
+          scoped_ptr<Event> event(new Event(event_name, args_copy.Pass()));
+          router->DispatchEventToExtension(extension_id, event.Pass());
+        }
+      }
+    }
+  }
+}
+
+}  // namespace chromedirectsetting
+}  // namespace extensions
+