Show offline interstitial page when offline and reload when reconnected to network.

chrome/browser/chromeos/offline/offline_load_service.h

+// Copyright (c) 2010 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_CHROMEOS_OFFLINE_OFFLINE_LOAD_SERVICE_H_
+#define CHROME_BROWSER_CHROMEOS_OFFLINE_OFFLINE_LOAD_SERVICE_H_
+
+#include <tr1/unordered_set>
+
+#include "base/ref_counted.h"
+#include "chrome/common/notification_observer.h"
+#include "chrome/common/notification_type.h"
+#include "chrome/common/notification_registrar.h"
+
+class GURL;
+class NavigationController;
+class TabContents;
+template<class A> class scoped_ptr;
+
+namespace chromeos {
+
+// OfflineLoadService decides whether or not the given url in the tab
+// should be loaded when the network is not available. The current
+// implementation simply memorize the tab that loads offline page.
+// TODO(oshima): Improve the logic so that we can automatically load
+// if there is valid cache content and/or it supports offline mode.
+class OfflineLoadService
+    : public NotificationObserver,
+      public base::RefCountedThreadSafe<OfflineLoadService> {
+ public:
+  // Returns the singleton instance of the offline load service.
+  static OfflineLoadService* Get();
+
+  // Returns true if the tab should proceed with loading the page even if
+  // it's offline.
+  bool ShouldProceed(int process_id, int render_view_id,
+                     const GURL& url) const;
+
+  // Record that the user pressed "procced" button for
+  // the tab_contents.
+  void Proceeded(int proceed_id, int render_view_id, const GURL& url);
+
+  // NotificationObserver implementation.
+  virtual void Observe(NotificationType type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details);
+
+ private:
+  friend class base::RefCountedThreadSafe<OfflineLoadService>;
+  friend class scoped_ptr<OfflineLoadService>;
+  friend class OfflineLoadServiceSingleton;
+
+  OfflineLoadService() {}
+  virtual ~OfflineLoadService() {}
+
+  // A method invoked in UI thread to remove |tab_contents| from |tabs_|.
+  void RemoveTabContents(TabContents* tab_contents);
+
+  // A method invoked in UI thread to register TAB_CLOSED
+  // notification.
+  void RegisterNotification(
+      NavigationController* navigation_controller);
+
+  NotificationRegistrar registrar_;
+
+  // Set of tabs that should proceed
+  std::tr1::unordered_set<const TabContents*> tabs_;
+
+  DISALLOW_COPY_AND_ASSIGN(OfflineLoadService);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_OFFLINE_OFFLINE_LOAD_SERVICE_H_