text: // 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_EXTENSIONS_EXTENSION_BROWSER_EVENT_ROUTER_H_
  #define CHROME_BROWSER_EXTENSIONS_EXTENSION_BROWSER_EVENT_ROUTER_H_
  #pragma once
  
  #include <map>
  #include <string>
  
  #include "base/basictypes.h"
  #include "base/singleton.h"
  #include "chrome/browser/browser_list.h"
  #include "chrome/browser/extensions/extension_tabs_module.h"
  #include "chrome/browser/tabs/tab_strip_model_observer.h"
  #include "chrome/common/notification_registrar.h"
  #if defined(TOOLKIT_VIEWS)
  #include "views/view.h"
  #include "views/focus/focus_manager.h"
  #elif defined(TOOLKIT_GTK)
  #include "app/active_window_watcher_x.h"
  #endif
  
  // The ExtensionBrowserEventRouter listens to Browser window & tab events
  // and routes them to listeners inside extension process renderers.
  // ExtensionBrowserEventRouter listens to *all* events, but will only route
  // events from windows/tabs within a profile to extension processes in the same
  // profile.
  class ExtensionBrowserEventRouter : public TabStripModelObserver,
  #if defined(TOOLKIT_VIEWS)
                                      public views::WidgetFocusChangeListener,
  #elif defined(TOOLKIT_GTK)
                                      public ActiveWindowWatcherX::Observer,
  #endif
                                      public BrowserList::Observer,
                                      public NotificationObserver {
   public:
    // Get Browser-Global instance.
    static ExtensionBrowserEventRouter* GetInstance();
  
    // Must be called once. Subsequent calls have no effect.
    void Init(Profile* profile);
  
    // BrowserList::Observer
    virtual void OnBrowserAdded(const Browser* browser);
    virtual void OnBrowserRemoved(const Browser* browser);
    virtual void OnBrowserSetLastActive(const Browser* browser);
  
  #if defined(TOOLKIT_VIEWS)
    virtual void NativeFocusWillChange(gfx::NativeView focused_before,
                                       gfx::NativeView focused_now);
  #elif defined(TOOLKIT_GTK)
    virtual void ActiveWindowChanged(GdkWindow* active_window);
  #endif
  
    // Called from Observe() on BROWSER_WINDOW_READY (not a part of
    // BrowserList::Observer).
    void OnBrowserWindowReady(const Browser* browser);
  
    // TabStripModelObserver
    virtual void TabInsertedAt(TabContentsWrapper* contents, int index,
                               bool foreground);
    virtual void TabClosingAt(TabStripModel* tab_strip_model,
                              TabContentsWrapper* contents,
                              int index);
    virtual void TabDetachedAt(TabContentsWrapper* contents, int index);
    virtual void TabSelectedAt(TabContentsWrapper* old_contents,
                               TabContentsWrapper* new_contents,
                               int index,
                               bool user_gesture);
    virtual void TabMoved(TabContentsWrapper* contents, int from_index,
                          int to_index);
    virtual void TabChangedAt(TabContentsWrapper* contents, int index,
                              TabChangeType change_type);
    virtual void TabReplacedAt(TabContentsWrapper* old_contents,
                               TabContentsWrapper* new_contents,
                               int index);
    virtual void TabPinnedStateChanged(TabContentsWrapper* contents, int index);
    virtual void TabStripEmpty();
  
    // Page Action execute event.
    void PageActionExecuted(Profile* profile,
                            const std::string& extension_id,
                            const std::string& page_action_id,
                            int tab_id,
                            const std::string& url,
                            int button);
    // Browser Actions execute event.
    void BrowserActionExecuted(Profile* profile,
                               const std::string& extension_id,
                               Browser* browser);
  
    // NotificationObserver.
    virtual void Observe(NotificationType type,
                         const NotificationSource& source,
                         const NotificationDetails& details);
   private:
    // "Synthetic" event. Called from TabInsertedAt if new tab is detected.
    void TabCreatedAt(TabContents* contents, int index, bool foreground);
  
    // Internal processing of tab updated events. Is called by both TabChangedAt
    // and Observe/NAV_ENTRY_COMMITTED.
    void TabUpdated(TabContents* contents, bool did_navigate);
  
    // Packages |changed_properties| as a tab updated event for the tab |contents|
    // and dispatches the event to the extension.
    void DispatchTabUpdatedEvent(TabContents* contents,
                                 DictionaryValue* changed_properties);
  
    // Called to dispatch a deprecated style page action click event that was
    // registered like:
    //   chrome.pageActions["name"].addListener(function(actionId, info){})
    void DispatchOldPageActionEvent(Profile* profile,
      const std::string& extension_id,
      const std::string& page_action_id,
      int tab_id,
      const std::string& url,
      int button);
  
    // Register ourselves to receive the various notifications we are interested
    // in for a browser.
    void RegisterForBrowserNotifications(const Browser* browser);
  
    // Register ourselves to receive the various notifications we are interested
    // in for a tab.
    void RegisterForTabNotifications(TabContents* contents);
  
    // Removes notifications added in RegisterForTabNotifications.
    void UnregisterForTabNotifications(TabContents* contents);
  
    ExtensionBrowserEventRouter();
    ~ExtensionBrowserEventRouter();
    friend struct DefaultSingletonTraits<ExtensionBrowserEventRouter>;
  
    NotificationRegistrar registrar_;
  
    bool initialized_;
  
    // Maintain some information about known tabs, so we can:
    //
    //  - distinguish between tab creation and tab insertion
    //  - not send tab-detached after tab-removed
    //  - reduce the "noise" of TabChangedAt() when sending events to extensions
    class TabEntry {
     public:
      // Create a new tab entry whose initial state is TAB_COMPLETE.  This
      // constructor is required because TabEntry objects placed inside an
      // std::map<> by value.
      TabEntry();
  
      // Update the load state of the tab based on its TabContents.  Returns true
      // if the state changed, false otherwise.  Whether the state has changed or
      // not is used to determine if events needs to be sent to extensions during
      // processing of TabChangedAt(). This method will "hold" a state-change
      // to "loading", until the DidNavigate() method which should always follow
      // it. Returns NULL if no updates should be sent.
      DictionaryValue* UpdateLoadState(const TabContents* contents);
  
      // Indicates that a tab load has resulted in a navigation and the
      // destination url is available for inspection. Returns NULL if no updates
      // should be sent.
      DictionaryValue* DidNavigate(const TabContents* contents);
  
     private:
      // Whether we are waiting to fire the 'complete' status change. This will
      // occur the first time the TabContents stops loading after the
      // NAV_ENTRY_COMMITTED was fired. The tab may go back into and out of the
      // loading state subsequently, but we will ignore those changes.
      bool complete_waiting_on_load_;
  
      GURL url_;
    };
  
    // Gets the TabEntry for the given |contents|. Returns TabEntry* if
    // found, NULL if not.
    TabEntry* GetTabEntry(const TabContents* contents);
  
    std::map<int, TabEntry> tab_entries_;
  
    // The currently focused window. We keep this so as to avoid sending multiple
    // windows.onFocusChanged events with the same windowId.
    int focused_window_id_;
  
    // The main profile (non-OTR) profile which will be used to send events not
    // associated with any browser.
    Profile* profile_;
  
    DISALLOW_COPY_AND_ASSIGN(ExtensionBrowserEventRouter);
  };
  
  #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_BROWSER_EVENT_ROUTER_H_
  