chrome/browser/search/search_terms_tracker.h

   1 // Copyright 2013 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_SEARCH_SEARCH_TERMS_TRACKER_H_
   6 #define CHROME_BROWSER_SEARCH_SEARCH_TERMS_TRACKER_H_
   7
   8 #include <map>
   9
  10 #include "base/strings/string16.h"
  11 #include "content/public/browser/notification_observer.h"
  12 #include "content/public/browser/notification_registrar.h"
  13
  14 namespace content {
  15 class NavigationController;
  16 class WebContents;
  17 }
  18
  19 namespace chrome {
  20
  21 // Observes navigation events (and WebContents destructions) to keep track of
  22 // search terms associated with a WebContents. Essentially, as long as there are
  23 // only web-triggerable navigations following a search results page, this class
  24 // will consider the search terms from that SRP as the "current" search terms.
  25 // Any other type of navigation will invalidate the search terms. The search
  26 // terms are being tracked so they can be displayed in the location bar for
  27 // related navigations that occur after a search.
  28 class SearchTermsTracker : public content::NotificationObserver {
  29  public:
  30   SearchTermsTracker();
  31   ~SearchTermsTracker() override;
  32
  33   // Returns the current search terms and navigation index of the corresponding
  34   // search results page for the specified WebContents. This function will
  35   // return true if there are valid search terms for |contents|. |search_terms|
  36   // and/or |navigation_index| can be NULL if not needed.
  37   bool GetSearchTerms(const content::WebContents* contents,
  38                       base::string16* search_terms,
  39                       int* navigation_index) const;
  40
  41   // content::NotificationObserver
  42   void Observe(int type,
  43                const content::NotificationSource& source,
  44                const content::NotificationDetails& details) override;
  45
  46  private:
  47   struct TabData {
  48     TabData() : srp_navigation_index(-1) {}
  49     base::string16 search_terms;
  50     int srp_navigation_index;
  51   };
  52
  53   // Keeps information about the specified WebContents.
  54   typedef std::map<const content::WebContents*, TabData> TabState;
  55
  56   // Searches for the most recent search and, if found, fills |tab_data| with
  57   // information about that search and returns true.
  58   bool FindMostRecentSearch(const content::NavigationController* controller,
  59                             TabData* tab_data);
  60
  61   // Removes the TabData entry associated to the specified |contents|.
  62   void RemoveTabData(const content::WebContents* contents);
  63
  64   content::NotificationRegistrar registrar_;
  65   TabState tabs_;
  66
  67   DISALLOW_COPY_AND_ASSIGN(SearchTermsTracker);
  68 };
  69
  70 }  // namespace chrome
  71
  72 #endif  // CHROME_BROWSER_SEARCH_SEARCH_TERMS_TRACKER_H_