components/bookmarks/browser/bookmark_index.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 COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_INDEX_H_
   6 #define COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_INDEX_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <string>
  11 #include <vector>
  12
  13 #include "base/basictypes.h"
  14 #include "base/strings/string16.h"
  15 #include "components/query_parser/query_parser.h"
  16
  17 class BookmarkNode;
  18
  19 namespace bookmarks {
  20
  21 class BookmarkClient;
  22 struct BookmarkMatch;
  23
  24 // BookmarkIndex maintains an index of the titles and URLs of bookmarks for
  25 // quick look up. BookmarkIndex is owned and maintained by BookmarkModel, you
  26 // shouldn't need to interact directly with BookmarkIndex.
  27 //
  28 // BookmarkIndex maintains the index (index_) as a map of sets. The map (type
  29 // Index) maps from a lower case string to the set (type NodeSet) of
  30 // BookmarkNodes that contain that string in their title or URL.
  31 class BookmarkIndex {
  32  public:
  33   // |languages| is used to help parse IDNs in URLs for the bookmark index.
  34   BookmarkIndex(BookmarkClient* client,
  35                 const std::string& languages);
  36   ~BookmarkIndex();
  37
  38   // Invoked when a bookmark has been added to the model.
  39   void Add(const BookmarkNode* node);
  40
  41   // Invoked when a bookmark has been removed from the model.
  42   void Remove(const BookmarkNode* node);
  43
  44   // Returns up to |max_count| of bookmarks containing each term from
  45   // the text |query| in either the title or the URL.
  46   void GetBookmarksMatching(
  47       const base::string16& query,
  48       size_t max_count,
  49       std::vector<BookmarkMatch>* results);
  50
  51  private:
  52   typedef std::vector<const BookmarkNode*> Nodes;
  53   typedef std::set<const BookmarkNode*> NodeSet;
  54   typedef std::map<base::string16, NodeSet> Index;
  55
  56   struct Match;
  57   typedef std::vector<Match> Matches;
  58
  59   // Extracts |matches.nodes| into Nodes, sorts the pairs in decreasing order of
  60   // typed count (if supported by the client), and then de-dupes the matches.
  61   void SortMatches(const Matches& matches, Nodes* sorted_nodes) const;
  62
  63   // Add |node| to |results| if the node matches the query.
  64   void AddMatchToResults(
  65       const BookmarkNode* node,
  66       query_parser::QueryParser* parser,
  67       const query_parser::QueryNodeStarVector& query_nodes,
  68       std::vector<BookmarkMatch>* results);
  69
  70   // Populates |matches| for the specified term. If |first_term| is true, this
  71   // is the first term in the query. Returns true if there is at least one node
  72   // matching the term.
  73   bool GetBookmarksMatchingTerm(const base::string16& term,
  74                                 bool first_term,
  75                                 Matches* matches);
  76
  77   // Iterates over |matches| updating each Match's nodes to contain the
  78   // intersection of the Match's current nodes and the nodes at |index_i|.
  79   // If the intersection is empty, the Match is removed.
  80   //
  81   // This is invoked from GetBookmarksMatchingTerm.
  82   void CombineMatchesInPlace(const Index::const_iterator& index_i,
  83                              Matches* matches);
  84
  85   // Iterates over |current_matches| calculating the intersection between the
  86   // Match's nodes and the nodes at |index_i|. If the intersection between the
  87   // two is non-empty, a new match is added to |result|.
  88   //
  89   // This differs from CombineMatchesInPlace in that if the intersection is
  90   // non-empty the result is added to result, not combined in place. This
  91   // variant is used for prefix matching.
  92   //
  93   // This is invoked from GetBookmarksMatchingTerm.
  94   void CombineMatches(const Index::const_iterator& index_i,
  95                       const Matches& current_matches,
  96                       Matches* result);
  97
  98   // Returns the set of query words from |query|.
  99   std::vector<base::string16> ExtractQueryWords(const base::string16& query);
 100
 101   // Adds |node| to |index_|.
 102   void RegisterNode(const base::string16& term, const BookmarkNode* node);
 103
 104   // Removes |node| from |index_|.
 105   void UnregisterNode(const base::string16& term, const BookmarkNode* node);
 106
 107   Index index_;
 108
 109   BookmarkClient* const client_;
 110
 111   // Languages used to help parse IDNs in URLs for the bookmark index.
 112   const std::string languages_;
 113
 114   DISALLOW_COPY_AND_ASSIGN(BookmarkIndex);
 115 };
 116
 117 }  // namespace bookmarks
 118
 119 #endif  // COMPONENTS_BOOKMARKS_BROWSER_BOOKMARK_INDEX_H_