1 // Copyright (c) 2012 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.
5 #ifndef CHROME_BROWSER_HISTORY_IN_MEMORY_URL_INDEX_TYPES_H_
6 #define CHROME_BROWSER_HISTORY_IN_MEMORY_URL_INDEX_TYPES_H_
12 #include "base/strings/string16.h"
13 #include "components/history/core/browser/history_types.h"
18 // The maximum number of characters to consider from an URL and page title
19 // while matching user-typed terms.
20 const size_t kMaxSignificantChars = 200;
22 // Matches within URL and Title Strings ----------------------------------------
24 // Specifies where an omnibox term occurs within a string. Used for specifying
25 // highlights in AutocompleteMatches (ACMatchClassifications) and to assist in
28 TermMatch() : term_num(0), offset(0), length(0) {}
29 TermMatch(int term_num, size_t offset, size_t length)
34 int term_num; // The index of the term in the original search string.
35 size_t offset; // The starting offset of the substring match.
36 size_t length; // The length of the substring match.
38 typedef std::vector<TermMatch> TermMatches;
40 // Returns a TermMatches which has an entry for each occurrence of the
41 // string |term| found in the string |cleaned_string|. Use
42 // CleanUpUrlForMatching() or CleanUpUrlTitleMatching() before passing
43 // |cleaned_string| to this function. The function marks each match
44 // with |term_num| so that the resulting TermMatches can be merged
45 // with other TermMatches for other terms. Note that only the first
46 // 2,048 characters of |string| are considered during the match
48 TermMatches MatchTermInString(const base::string16& term,
49 const base::string16& cleaned_string,
52 // Sorts and removes overlapping substring matches from |matches| and
53 // returns the cleaned up matches.
54 TermMatches SortAndDeoverlapMatches(const TermMatches& matches);
56 // Extracts and returns the offsets from |matches|. This includes both
57 // the offsets corresponding to the beginning of a match and the offsets
58 // corresponding to the end of a match (i.e., offset+length for that match).
59 std::vector<size_t> OffsetsFromTermMatches(const TermMatches& matches);
61 // Replaces the offsets and lengths in |matches| with those given in |offsets|.
62 // |offsets| gives beginning and ending offsets for each match; this function
63 // translates (beginning, ending) offset into (beginning offset, length of
64 // match). It deletes any matches for which an endpoint is npos and returns
65 // the updated list of matches.
66 TermMatches ReplaceOffsetsInTermMatches(const TermMatches& matches,
67 const std::vector<size_t>& offsets);
69 // Convenience Types -----------------------------------------------------------
71 typedef std::vector<base::string16> String16Vector;
72 typedef std::set<base::string16> String16Set;
73 typedef std::set<base::char16> Char16Set;
74 typedef std::vector<base::char16> Char16Vector;
76 // A vector that contains the offsets at which each word starts within a string.
77 typedef std::vector<size_t> WordStarts;
79 // Utility Functions -----------------------------------------------------------
81 // Breaks the string |cleaned_uni_string| down into individual words.
82 // Use CleanUpUrlForMatching() or CleanUpUrlTitleMatching() before
83 // passing |cleaned_uni_string| to this function. If |word_starts| is
84 // not NULL then clears and pushes the offsets within
85 // |cleaned_uni_string| at which each word starts onto
86 // |word_starts|. These offsets are collected only up to the first
87 // kMaxSignificantChars of |cleaned_uni_string|.
88 String16Set String16SetFromString16(const base::string16& cleaned_uni_string,
89 WordStarts* word_starts);
91 // Breaks the |cleaned_uni_string| string down into individual words
92 // and return a vector with the individual words in their original
93 // order. Use CleanUpUrlForMatching() or CleanUpUrlTitleMatching()
94 // before passing |cleaned_uni_string| to this function. If
95 // |break_on_space| is false then the resulting list will contain only
96 // words containing alpha-numeric characters. If |break_on_space| is
97 // true then the resulting list will contain strings broken at
98 // whitespace. (|break_on_space| indicates that the
99 // BreakIterator::BREAK_SPACE (equivalent to BREAK_LINE) approach is
100 // to be used. For a complete description of this algorithm refer to
101 // the comments in base/i18n/break_iterator.h.) If |word_starts| is
102 // not NULL then clears and pushes the word starts onto |word_starts|.
105 // Given: |cleaned_uni_string|: "http://www.google.com/ harry the rabbit."
106 // With |break_on_space| false the returned list will contain:
107 // "http", "www", "google", "com", "harry", "the", "rabbit"
108 // With |break_on_space| true the returned list will contain:
109 // "http://", "www.google.com/", "harry", "the", "rabbit."
110 String16Vector String16VectorFromString16(
111 const base::string16& cleaned_uni_string,
113 WordStarts* word_starts);
115 // Breaks the |uni_word| string down into its individual characters.
116 // Note that this is temporarily intended to work on a single word, but
117 // _will_ work on a string of words, perhaps with unexpected results.
118 // TODO(mrossetti): Lots of optimizations possible here for not restarting
119 // a search if the user is just typing along. Also, change this to uniString
120 // and properly handle substring matches, scoring and sorting the results
121 // by score. Also, provide the metrics for where the matches occur so that
122 // the UI can highlight the matched sections.
123 Char16Set Char16SetFromString16(const base::string16& uni_word);
125 // Support for InMemoryURLIndex Private Data -----------------------------------
127 // An index into a list of all of the words we have indexed.
128 typedef size_t WordID;
130 // A map allowing a WordID to be determined given a word.
131 typedef std::map<base::string16, WordID> WordMap;
133 // A map from character to the word_ids of words containing that character.
134 typedef std::set<WordID> WordIDSet; // An index into the WordList.
135 typedef std::map<base::char16, WordIDSet> CharWordIDMap;
137 // A map from word (by word_id) to history items containing that word.
138 typedef history::URLID HistoryID;
139 typedef std::set<HistoryID> HistoryIDSet;
140 typedef std::vector<HistoryID> HistoryIDVector;
141 typedef std::map<WordID, HistoryIDSet> WordIDHistoryMap;
142 typedef std::map<HistoryID, WordIDSet> HistoryIDWordMap;
145 // Information used in scoring a particular URL.
146 typedef std::vector<VisitInfo> VisitInfoVector;
147 struct HistoryInfoMapValue {
148 HistoryInfoMapValue();
149 ~HistoryInfoMapValue();
151 // This field is always populated.
154 // This field gets filled in asynchronously after a visit. As such,
155 // it's almost always correct. If it's wrong, it's likely to either
156 // be empty (if this URL was recently added to the index) or
157 // slightly out-of-date (one visit behind).
158 VisitInfoVector visits;
161 // A map from history_id to the history's URL and title.
162 typedef std::map<HistoryID, HistoryInfoMapValue> HistoryInfoMap;
164 // A map from history_id to URL and page title word start metrics.
165 struct RowWordStarts {
169 // Clears both url_word_starts_ and title_word_starts_.
172 WordStarts url_word_starts_;
173 WordStarts title_word_starts_;
175 typedef std::map<HistoryID, RowWordStarts> WordStartsMap;
177 } // namespace history
179 #endif // CHROME_BROWSER_HISTORY_IN_MEMORY_URL_INDEX_TYPES_H_