Move system.* family of APIs to extensions/

chrome/browser/extensions/api/system_info/system_info_api.cc

-// Copyright 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/system_info/system_info_api.h"
-
-#include <set>
-
-#include "base/bind.h"
-#include "base/lazy_instance.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/singleton.h"
-#include "base/strings/string_util.h"
-#include "base/values.h"
-#include "chrome/browser/browser_process.h"
-#include "chrome/browser/extensions/api/system_display/display_info_provider.h"
-#include "chrome/browser/extensions/api/system_storage/storage_info_provider.h"
-#include "chrome/browser/extensions/event_router_forwarder.h"
-#include "chrome/common/extensions/api/system_display.h"
-#include "chrome/common/extensions/api/system_storage.h"
-#include "components/storage_monitor/removable_storage_observer.h"
-#include "components/storage_monitor/storage_info.h"
-#include "components/storage_monitor/storage_monitor.h"
-#include "content/public/browser/browser_thread.h"
-#include "ui/gfx/display_observer.h"
-#include "ui/gfx/screen.h"
-
-namespace extensions {
-
-using api::system_storage::StorageUnitInfo;
-using content::BrowserThread;
-using storage_monitor::StorageMonitor;
-
-namespace system_display = api::system_display;
-namespace system_storage = api::system_storage;
-
-namespace {
-
-bool IsDisplayChangedEvent(const std::string& event_name) {
-  return event_name == system_display::OnDisplayChanged::kEventName;
-}
-
-bool IsSystemStorageEvent(const std::string& event_name) {
-  return (event_name == system_storage::OnAttached::kEventName ||
-          event_name == system_storage::OnDetached::kEventName);
-}
-
-// Event router for systemInfo API. It is a singleton instance shared by
-// multiple profiles.
-class SystemInfoEventRouter : public gfx::DisplayObserver,
-                              public storage_monitor::RemovableStorageObserver {
- public:
-  static SystemInfoEventRouter* GetInstance();
-
-  SystemInfoEventRouter();
-  virtual ~SystemInfoEventRouter();
-
-  // Add/remove event listener for the |event_name| event.
-  void AddEventListener(const std::string& event_name);
-  void RemoveEventListener(const std::string& event_name);
-
- private:
-  // gfx::DisplayObserver:
-  virtual void OnDisplayAdded(const gfx::Display& new_display) OVERRIDE;
-  virtual void OnDisplayRemoved(const gfx::Display& old_display) OVERRIDE;
-  virtual void OnDisplayMetricsChanged(const gfx::Display& display,
-                                       uint32_t metrics) OVERRIDE;
-
-  // RemovableStorageObserver implementation.
-  virtual void OnRemovableStorageAttached(
-      const storage_monitor::StorageInfo& info) OVERRIDE;
-  virtual void OnRemovableStorageDetached(
-      const storage_monitor::StorageInfo& info) OVERRIDE;
-
-  // Called from any thread to dispatch the systemInfo event to all extension
-  // processes cross multiple profiles.
-  void DispatchEvent(const std::string& event_name,
-                     scoped_ptr<base::ListValue> args);
-
-  // Called to dispatch the systemInfo.display.onDisplayChanged event.
-  void OnDisplayChanged();
-
-  // Used to record the event names being watched.
-  std::multiset<std::string> watching_event_set_;
-
-  bool has_storage_monitor_observer_;
-
-  DISALLOW_COPY_AND_ASSIGN(SystemInfoEventRouter);
-};
-
-static base::LazyInstance<SystemInfoEventRouter>::Leaky
-    g_system_info_event_router = LAZY_INSTANCE_INITIALIZER;
-
-// static
-SystemInfoEventRouter* SystemInfoEventRouter::GetInstance() {
-  return g_system_info_event_router.Pointer();
-}
-
-SystemInfoEventRouter::SystemInfoEventRouter()
-    : has_storage_monitor_observer_(false) {
-}
-
-SystemInfoEventRouter::~SystemInfoEventRouter() {
-  if (has_storage_monitor_observer_) {
-    StorageMonitor* storage_monitor = StorageMonitor::GetInstance();
-    if (storage_monitor)
-      storage_monitor->RemoveObserver(this);
-  }
-}
-
-void SystemInfoEventRouter::AddEventListener(const std::string& event_name) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-
-  watching_event_set_.insert(event_name);
-  if (watching_event_set_.count(event_name) > 1)
-    return;
-
-  if (IsDisplayChangedEvent(event_name)) {
-    gfx::Screen* screen = DisplayInfoProvider::Get()->GetActiveScreen();
-    if (screen)
-      screen->AddObserver(this);
-  }
-
-  if (IsSystemStorageEvent(event_name)) {
-    if (!has_storage_monitor_observer_) {
-      has_storage_monitor_observer_ = true;
-      DCHECK(StorageMonitor::GetInstance()->IsInitialized());
-      StorageMonitor::GetInstance()->AddObserver(this);
-    }
-  }
-}
-
-void SystemInfoEventRouter::RemoveEventListener(const std::string& event_name) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-
-  std::multiset<std::string>::iterator it =
-      watching_event_set_.find(event_name);
-  if (it != watching_event_set_.end()) {
-    watching_event_set_.erase(it);
-    if (watching_event_set_.count(event_name) > 0)
-      return;
-  }
-
-  if (IsDisplayChangedEvent(event_name)) {
-    gfx::Screen* screen = DisplayInfoProvider::Get()->GetActiveScreen();
-    if (screen)
-      screen->RemoveObserver(this);
-  }
-
-  if (IsSystemStorageEvent(event_name)) {
-    const std::string& other_event_name =
-        (event_name == system_storage::OnDetached::kEventName) ?
-            system_storage::OnAttached::kEventName :
-            system_storage::OnDetached::kEventName;
-    if (watching_event_set_.count(other_event_name) == 0) {
-      StorageMonitor::GetInstance()->RemoveObserver(this);
-      has_storage_monitor_observer_ = false;
-    }
-  }
-}
-
-void SystemInfoEventRouter::OnRemovableStorageAttached(
-    const storage_monitor::StorageInfo& info) {
-  StorageUnitInfo unit;
-  systeminfo::BuildStorageUnitInfo(info, &unit);
-  scoped_ptr<base::ListValue> args(new base::ListValue);
-  args->Append(unit.ToValue().release());
-  DispatchEvent(system_storage::OnAttached::kEventName, args.Pass());
-}
-
-void SystemInfoEventRouter::OnRemovableStorageDetached(
-    const storage_monitor::StorageInfo& info) {
-  scoped_ptr<base::ListValue> args(new base::ListValue);
-  std::string transient_id =
-      StorageMonitor::GetInstance()->GetTransientIdForDeviceId(
-          info.device_id());
-  args->AppendString(transient_id);
-
-  DispatchEvent(system_storage::OnDetached::kEventName, args.Pass());
-}
-
-void SystemInfoEventRouter::OnDisplayAdded(const gfx::Display& new_display) {
-  OnDisplayChanged();
-}
-
-void SystemInfoEventRouter::OnDisplayRemoved(const gfx::Display& old_display) {
-  OnDisplayChanged();
-}
-
-void SystemInfoEventRouter::OnDisplayMetricsChanged(const gfx::Display& display,
-                                                    uint32_t metrics) {
-  OnDisplayChanged();
-}
-
-void SystemInfoEventRouter::OnDisplayChanged() {
-  scoped_ptr<base::ListValue> args(new base::ListValue());
-  DispatchEvent(system_display::OnDisplayChanged::kEventName, args.Pass());
-}
-
-void SystemInfoEventRouter::DispatchEvent(const std::string& event_name,
-                                          scoped_ptr<base::ListValue> args) {
-  g_browser_process->extension_event_router_forwarder()->
-      BroadcastEventToRenderers(event_name, args.Pass(), GURL());
-}
-
-void AddEventListener(const std::string& event_name) {
-  SystemInfoEventRouter::GetInstance()->AddEventListener(event_name);
-}
-
-void RemoveEventListener(const std::string& event_name) {
-  SystemInfoEventRouter::GetInstance()->RemoveEventListener(event_name);
-}
-
-}  // namespace
-
-static base::LazyInstance<BrowserContextKeyedAPIFactory<SystemInfoAPI> >
-    g_factory = LAZY_INSTANCE_INITIALIZER;
-
-// static
-BrowserContextKeyedAPIFactory<SystemInfoAPI>*
-SystemInfoAPI::GetFactoryInstance() {
-  return g_factory.Pointer();
-}
-
-SystemInfoAPI::SystemInfoAPI(content::BrowserContext* context)
-    : browser_context_(context) {
-  EventRouter* router = EventRouter::Get(browser_context_);
-  router->RegisterObserver(this, system_storage::OnAttached::kEventName);
-  router->RegisterObserver(this, system_storage::OnDetached::kEventName);
-  router->RegisterObserver(this, system_display::OnDisplayChanged::kEventName);
-}
-
-SystemInfoAPI::~SystemInfoAPI() {
-}
-
-void SystemInfoAPI::Shutdown() {
-  EventRouter::Get(browser_context_)->UnregisterObserver(this);
-}
-
-void SystemInfoAPI::OnListenerAdded(const EventListenerInfo& details) {
-  if (IsSystemStorageEvent(details.event_name)) {
-    StorageMonitor::GetInstance()->EnsureInitialized(
-        base::Bind(&AddEventListener, details.event_name));
-  } else {
-    AddEventListener(details.event_name);
-  }
-}
-
-void SystemInfoAPI::OnListenerRemoved(const EventListenerInfo& details) {
-  if (IsSystemStorageEvent(details.event_name)) {
-    StorageMonitor::GetInstance()->EnsureInitialized(
-        base::Bind(&RemoveEventListener, details.event_name));
-  } else {
-    RemoveEventListener(details.event_name);
-  }
-}
-
-}  // namespace extensions