1 // Copyright (c) 2011 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_HISTORY_TOP_SITES_CACHE_H_ 6 #define CHROME_BROWSER_HISTORY_TOP_SITES_CACHE_H_ 7 #pragma once 8 9 #include <algorithm> 10 #include <map> 11 #include <string> 12 13 #include "base/memory/ref_counted.h" 14 #include "chrome/browser/history/history_types.h" 15 16 class RefCountedBytes; 17 18 namespace history { 19 20 // TopSitesCache caches the top sites and thumbnails for TopSites. 21 class TopSitesCache { 22 public: 23 TopSitesCache(); 24 ~TopSitesCache(); 25 26 // The top sites. 27 void SetTopSites(const MostVisitedURLList& top_sites); 28 const MostVisitedURLList& top_sites() const { return top_sites_; } 29 30 // The thumbnails. 31 void SetThumbnails(const URLToImagesMap& images); 32 const URLToImagesMap& images() const { return images_; } 33 34 // Set a thumbnail. 35 void SetPageThumbnail(const GURL& url, 36 RefCountedBytes* thumbnail, 37 const ThumbnailScore& score); 38 39 // Returns the thumbnail as an Image for the specified url. This adds an entry 40 // for |url| if one has not yet been added. 41 Images* GetImage(const GURL& url); 42 43 // Fetches the thumbnail for the specified url. Returns true if there is a 44 // thumbnail for the specified url. 45 bool GetPageThumbnail(const GURL& url, 46 scoped_refptr<RefCountedBytes>* bytes); 47 48 // Fetches the thumbnail score for the specified url. Returns true if 49 // there is a thumbnail score for the specified url. 50 bool GetPageThumbnailScore(const GURL& url, ThumbnailScore* score); 51 52 // Returns the canonical URL for |url|. 53 GURL GetCanonicalURL(const GURL& url); 54 55 // Returns true if |url| is known. 56 bool IsKnownURL(const GURL& url); 57 58 // Returns the index into |top_sites_| for |url|. 59 size_t GetURLIndex(const GURL& url); 60 61 // Removes any thumbnails that are no longer referenced by the top sites. 62 void RemoveUnreferencedThumbnails(); 63 64 private: 65 // The entries in CanonicalURLs, see CanonicalURLs for details. The second 66 // argument gives the index of the URL into MostVisitedURLs redirects. 67 typedef std::pair<MostVisitedURL*, size_t> CanonicalURLEntry; 68 69 // Comparator used for CanonicalURLs. 70 class CanonicalURLComparator { 71 public: 72 bool operator()(const CanonicalURLEntry& e1, 73 const CanonicalURLEntry& e2) const { 74 return e1.first->redirects[e1.second] < e2.first->redirects[e2.second]; 75 } 76 }; 77 78 // This is used to map from redirect url to the MostVisitedURL the redirect is 79 // from. Ideally this would be map<GURL, size_t> (second param indexing into 80 // top_sites_), but this results in duplicating all redirect urls. As some 81 // sites have a lot of redirects, we instead use the MostVisitedURL* and the 82 // index of the redirect as the key, and the index into top_sites_ as the 83 // value. This way we aren't duplicating GURLs. CanonicalURLComparator 84 // enforces the ordering as if we were using GURLs. 85 typedef std::map<CanonicalURLEntry, size_t, 86 CanonicalURLComparator> CanonicalURLs; 87 88 // Generates the set of canonical urls from |top_sites_|. 89 void GenerateCanonicalURLs(); 90 91 // Stores a set of redirects. This is used by GenerateCanonicalURLs. 92 void StoreRedirectChain(const RedirectList& redirects, size_t destination); 93 94 // Returns the iterator into canconical_urls_ for the specified url. 95 CanonicalURLs::iterator GetCanonicalURLsIterator(const GURL& url); 96 97 // The top sites. 98 MostVisitedURLList top_sites_; 99 100 // The images. These map from canonical url to image. 101 URLToImagesMap images_; 102 103 // Generated from the redirects to and from the most visited pages. See 104 // description above typedef for details. 105 CanonicalURLs canonical_urls_; 106 107 DISALLOW_COPY_AND_ASSIGN(TopSitesCache); 108 }; 109 110 } // namespace history 111 112 #endif // CHROME_BROWSER_HISTORY_TOP_SITES_CACHE_H_ 113
