Implement sidebar support for extension action popups

chrome/browser/extensions/sidebar_manager.h

+// Copyright (c) 2015 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_EXTENSIONS_SIDEBAR_MANAGER_H_
+#define CHROME_BROWSER_EXTENSIONS_SIDEBAR_MANAGER_H_
+
+#include <map>
+#include <string>
+
+#include "base/memory/ref_counted.h"
+#include "base/observer_list.h"
+#include "base/strings/string16.h"
+#include "chrome/browser/extensions/sidebar_container.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+class GURL;
+class SidebarContainer;
+class SidebarManagerObserver;
+
+namespace content {
+class BrowserContext;
+class WebContents;
+}
+
+namespace extensions {
+///////////////////////////////////////////////////////////////////////////////
+// SidebarManager
+//
+//  This class is a singleton that manages SidebarContainer instances and
+//  maintains a connection between tabs and sidebars.
+//
+class SidebarManager : public content::NotificationObserver,
+                       public base::RefCounted<SidebarManager> {

[Devlin, 2015/06/04 18:00:14]

Is there a reason this is refcounted?

+ public:
+  // Returns SidebarManager instance registered with BrowserContext.
+  static SidebarManager* GetFromContext(content::BrowserContext* context);
+
+  SidebarManager();
+
+  // Returns SidebarContainer registered for |tab| and active or NULL if
+  // there is no alive and active SidebarContainer registered for |tab|.
+  SidebarContainer* GetActiveSidebarContainerFor(content::WebContents* tab);
+
+  // Returns SidebarContainer registered for |tab| and |content_id| or NULL if
+  // there is no such SidebarContainer registered.
+  SidebarContainer* GetSidebarContainerFor(content::WebContents* tab,
+                                           const std::string& content_id);
+
+  // Returns sidebar's TabContents registered for |tab| and |content_id|.
+  content::WebContents* GetSidebarTabContents(content::WebContents* tab,
+                                              const std::string& content_id);
+
+  // Sends sidebar state change notification to extensions.
+  void NotifyStateChanges(content::WebContents* was_active_sidebar_contents,
+                          content::WebContents* active_sidebar_contents);
+
+  // Shows sidebar identified by |tab| and |content_id| (only sidebar's
+  // mini tab is visible).
+  void ShowSidebar(content::WebContents* tab,
+                   const std::string& content_id,
+                   const GURL& url,
+                   Browser* browser);
+
+  // Expands sidebar identified by |tab| and |content_id|.
+  void ExpandSidebar(content::WebContents* tab, const std::string& content_id);
+
+  // Collapses sidebar identified by |tab| and |content_id| (has no effect
+  // if sidebar is not expanded).
+  void CollapseSidebar(content::WebContents* tab,
+                       const std::string& content_id);
+
+  SidebarContainer* MigrateSidebarTo(content::WebContents* tab);
+  // Hides sidebar identified by |tab| and |content_id| (removes sidebar's
+  // mini tab).
+  void HideSidebar(content::WebContents* tab, const std::string& content_id);
+
+  // Navigates sidebar identified by |tab| and |content_id| to |url|.
+  void NavigateSidebar(content::WebContents* tab,
+                       const std::string& content_id,
+                       const GURL& url);
+
+  void AddObserver(SidebarManagerObserver* observer);
+  void RemoveObserver(SidebarManagerObserver* observer);
+
+ private:
+  friend class base::RefCounted<SidebarManager>;
+
+  ~SidebarManager() override;
+
+  // Overridden from content::NotificationObserver.
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
+
+  // Hides all sidebars registered for |tab|.
+  void HideAllSidebars(content::WebContents* tab);
+
+  // Returns SidebarContainer corresponding to |sidebar_contents|.
+  SidebarContainer* FindSidebarContainerFor(
+      content::WebContents* sidebar_contents);
+
+  // Registers new SidebarContainer for |tab|. There must be no
+  // other SidebarContainers registered for the RenderViewHost at the moment.
+  void RegisterSidebarContainerFor(content::WebContents* tab,
+                                   SidebarContainer* container);
+
+  // Unregisters SidebarContainer identified by |tab| and |content_id|.
+  void UnregisterSidebarContainerFor(content::WebContents* tab,
+                                     const std::string& content_id);
+
+  // Records the link between |tab| and |container|.
+  void BindSidebarContainer(content::WebContents* tab,
+                            SidebarContainer* container);
+
+  // Forgets the link between |tab| and |container|.
+  void UnbindSidebarContainer(content::WebContents* tab,
+                              SidebarContainer* container);
+
+  content::NotificationRegistrar registrar_;
+
+  // This map stores sidebars linked to a particular tab. Sidebars are
+  // identified by their unique content id (string).
+  typedef std::map<std::string, SidebarContainer*>
+      ContentIdToSidebarContainerMap;
+
+  // These two maps are for tracking dependencies between tabs and
+  // their SidebarContainers.
+  //
+  // SidebarManager start listening to SidebarContainers when they are put
+  // into these maps and removes them when they are closing.
+  struct SidebarStateForTab;
+  typedef std::map<content::WebContents*, SidebarStateForTab>
+      TabToSidebarContainerMap;
+  TabToSidebarContainerMap tab_to_sidebar_container_;
+
+  typedef std::map<SidebarContainer*, content::WebContents*>
+      SidebarContainerToTabMap;
+  SidebarContainerToTabMap sidebar_container_to_tab_;
+
+  ObserverList<SidebarManagerObserver> observer_list_;
+
+  DISALLOW_COPY_AND_ASSIGN(SidebarManager);
+};
+
+} // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_SIDEBAR_MANAGER_H_