chrome/browser/alternate_nav_url_fetcher.h

   1 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_ALTERNATE_NAV_URL_FETCHER_H_
   6 #define CHROME_BROWSER_ALTERNATE_NAV_URL_FETCHER_H_
   7
   8 #include <string>
   9
  10 #include "chrome/browser/url_fetcher.h"
  11 #include "chrome/common/notification_registrar.h"
  12 #include "chrome/common/notification_service.h"
  13
  14 class NavigationController;
  15
  16 // Attempts to get the HEAD of a host name and displays an info bar if the
  17 // request was successful. This is used for single-word queries where we can't
  18 // tell if the entry was a search or an intranet hostname. The autocomplete bar
  19 // assumes it's a query and issues an AlternateNavURLFetcher to display a "did
  20 // you mean" infobar suggesting a navigation.
  21 //
  22 // The memory management of this object is a bit tricky. The location bar view
  23 // will create us and be responsible for us until we attach as an observer
  24 // after a pending load starts (it will delete us if this doesn't happen).
  25 // Once this pending load starts, we're responsible for deleting ourselves.
  26 // We'll do this when the load commits, or when the navigation controller
  27 // itself is deleted.
  28 class AlternateNavURLFetcher : public NotificationObserver,
  29                                public URLFetcher::Delegate {
  30  public:
  31   enum State {
  32     NOT_STARTED,
  33     IN_PROGRESS,
  34     SUCCEEDED,
  35     FAILED,
  36   };
  37
  38   explicit AlternateNavURLFetcher(const std::wstring& alternate_nav_url);
  39
  40   State state() const { return state_; }
  41
  42   // NotificationObserver
  43   virtual void Observe(NotificationType type,
  44                        const NotificationSource& source,
  45                        const NotificationDetails& details);
  46
  47   // URLFetcher::Delegate
  48   virtual void OnURLFetchComplete(const URLFetcher* source,
  49                                   const GURL& url,
  50                                   const URLRequestStatus& status,
  51                                   int response_code,
  52                                   const ResponseCookies& cookies,
  53                                   const std::string& data);
  54
  55  private:
  56   // Displays the infobar if all conditions are met (the page has loaded and
  57   // the fetch of the alternate URL succeeded). If the infobar is displayed,
  58   // this object is no longer necessary and this function WILL DELETE |this|!.
  59   void ShowInfobarIfPossible();
  60
  61   std::wstring alternate_nav_url_;
  62   scoped_ptr<URLFetcher> fetcher_;
  63   NavigationController* controller_;
  64   State state_;
  65   bool navigated_to_entry_;
  66
  67   NotificationRegistrar registrar_;
  68
  69   DISALLOW_COPY_AND_ASSIGN(AlternateNavURLFetcher);
  70 };
  71
  72 #endif  // CHROME_BROWSER_ALTERNATE_NAV_URL_FETCHER_H_
  73