src/chrome/browser/search/suggestions/thumbnail_manager.h

   1 // Copyright 2014 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_SUGGESTIONS_THUMBNAIL_MANAGER_H_
   6 #define CHROME_BROWSER_SEARCH_SUGGESTIONS_THUMBNAIL_MANAGER_H_
   7
   8 #include <map>
   9 #include <utility>
  10 #include <vector>
  11
  12 #include "base/basictypes.h"
  13 #include "base/callback.h"
  14 #include "chrome/browser/bitmap_fetcher/bitmap_fetcher.h"
  15 #include "ui/gfx/image/image_skia.h"
  16 #include "url/gurl.h"
  17
  18 class Profile;
  19
  20 namespace suggestions {
  21
  22 class SuggestionsProfile;
  23
  24 // A class used to fetch server thumbnails asynchronously.
  25 class ThumbnailManager : public chrome::BitmapFetcherDelegate {
  26  public:
  27   explicit ThumbnailManager(Profile* profile);
  28   virtual ~ThumbnailManager();
  29
  30   // Initializes the |thumbnail_map_| with the proper mapping from website URL
  31   // to thumbnail URL.
  32   void InitializeThumbnailMap(const SuggestionsProfile& suggestions);
  33
  34   // Retrieves stored thumbnail for website |url| asynchronously. Calls
  35   // |callback| with Bitmap pointer if found, and NULL otherwise. Should be
  36   // called from the UI thread.
  37   void GetPageThumbnail(
  38       const GURL& url,
  39       base::Callback<void(const GURL&, const SkBitmap*)> callback);
  40
  41  private:
  42   FRIEND_TEST_ALL_PREFIXES(ThumbnailManagerTest, InitializeThumbnailMapTest);
  43   FRIEND_TEST_ALL_PREFIXES(ThumbnailManagerBrowserTest, FetchThumbnails);
  44   FRIEND_TEST_ALL_PREFIXES(ThumbnailManagerBrowserTest, FetchThumbnailsInvalid);
  45   FRIEND_TEST_ALL_PREFIXES(ThumbnailManagerBrowserTest,
  46                            FetchThumbnailsMultiple);
  47
  48   typedef std::vector<base::Callback<void(const GURL&, const SkBitmap*)> >
  49       CallbackVector;
  50
  51   // State related to a thumbnail fetch (associated website url, fetcher,
  52   // pending callbacks).
  53   struct ThumbnailRequest {
  54     ThumbnailRequest();
  55     explicit ThumbnailRequest(chrome::BitmapFetcher* f);
  56     ~ThumbnailRequest();
  57
  58     void swap(ThumbnailRequest* other) {
  59       std::swap(url, other->url);
  60       std::swap(callbacks, other->callbacks);
  61       std::swap(fetcher, other->fetcher);
  62     }
  63
  64     GURL url;
  65     chrome::BitmapFetcher* fetcher;
  66     // Queue for pending callbacks, which may accumulate while the request is in
  67     // flight.
  68     CallbackVector callbacks;
  69   };
  70
  71   typedef std::map<const GURL, ThumbnailRequest> ThumbnailRequestMap;
  72
  73   // Inherited from BitmapFetcherDelegate. Runs on the UI thread.
  74   virtual void OnFetchComplete(const GURL thumbnail_url,
  75                                const SkBitmap* bitmap) OVERRIDE;
  76
  77   // Looks up thumbnail for |url|. If found, writes the result to
  78   // |thumbnail_url| and returns true. Otherwise just returns false.
  79   bool GetThumbnailURL(const GURL& url, GURL* thumbnail_url);
  80
  81   // Used for substituting the request context during testing.
  82   void set_request_context(net::URLRequestContextGetter* context) {
  83     url_request_context_ = context;
  84   }
  85
  86   // Map from URL to thumbnail URL. Should be kept up to date when a new
  87   // SuggestionsProfile is available.
  88   std::map<GURL, GURL> thumbnail_map_;
  89
  90   // Map from each thumbnail URL to the request information (associated website
  91   // url, fetcher, pending callbacks).
  92   ThumbnailRequestMap pending_requests_;
  93
  94   net::URLRequestContextGetter* url_request_context_;
  95
  96   DISALLOW_COPY_AND_ASSIGN(ThumbnailManager);
  97 };
  98
  99 }  // namespace suggestions
 100
 101 #endif  // CHROME_BROWSER_SEARCH_SUGGESTIONS_THUMBNAIL_MANAGER_H_