Componentize ScoredHistoryMatch

chrome/browser/autocomplete/scored_history_match_builder_impl.h

Index: chrome/browser/autocomplete/scored_history_match_builder_impl.h
diff --git a/chrome/browser/history/scored_history_match.h b/chrome/browser/autocomplete/scored_history_match_builder_impl.h
similarity index 20%
copy from chrome/browser/history/scored_history_match.h
copy to chrome/browser/autocomplete/scored_history_match_builder_impl.h
index 15a37e7bd73673dc4efe2ca93a5e29a06d3e8d59..b1728f2b28aefd0703a18de64480760e2ac965dd 100644
--- a/chrome/browser/history/scored_history_match.h
+++ b/chrome/browser/autocomplete/scored_history_match_builder_impl.h
@@ -2,121 +2,92 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_HISTORY_SCORED_HISTORY_MATCH_H_
-#define CHROME_BROWSER_HISTORY_SCORED_HISTORY_MATCH_H_
-
-#include <map>
-#include <set>
-#include <vector>
+#ifndef CHROME_BROWSER_AUTOCOMPLETE_SCORED_HISTORY_MATCH_BUILDER_IMPL_H_
+#define CHROME_BROWSER_AUTOCOMPLETE_SCORED_HISTORY_MATCH_BUILDER_IMPL_H_
 
+#include "base/callback.h"
 #include "base/strings/string16.h"
-#include "components/history/core/browser/history_match.h"
 #include "components/history/core/browser/history_types.h"
 #include "components/history/core/browser/in_memory_url_index_types.h"
+#include "components/history/core/browser/scored_history_match.h"
 #include "testing/gtest/include/gtest/gtest_prod.h"
 
-namespace history {
-
-class HistoryClient;
-class ScoredHistoryMatchTest;
-
-// An HistoryMatch that has a score as well as metrics defining where in the
-// history item's URL and/or page title matches have occurred.
-class ScoredHistoryMatch : public history::HistoryMatch {
+class ScoredHistoryMatchBuilderImplTest;
+
+// ScoredHistoryMatchBuilderImpl's Build method creates new history matches with
+// a raw score calculated for the history item given in |row| with recent visits
+// as indicated in |visits|. It first determines if the row qualifies by seeing
+// if all of the terms in |terms_vector| occur in |row|.  If so, calculates a
+// raw score.  This raw score is in part determined by whether the matches occur
+// at word boundaries, the locations of which are stored in |word_starts|.  For
+// some terms, it's appropriate to look for the word boundary within the term.
+// For instance, the term ".net" should look for a word boundary at the "n".
+// These offsets (".net" should have an offset of 1) come from
+// |terms_to_word_starts_offsets|. |is_bookmarked| is used to determine if the
+// match's URL is referenced by any bookmarks, which can also affect the raw
+// score.  The raw score allows the matches to be ordered and can be/ used to
+// influence the final score calculated by the client of this index.  If the row
+// does not qualify the raw score will be 0.  |languages| is used to help
+// parse/format the URL before looking for the terms.
+class ScoredHistoryMatchBuilderImpl
+    : public history::ScoredHistoryMatch::Builder {
  public:
-  // The maximum number of recent visits to examine in GetFrequency().
-  // Public so url_index_private_data.cc knows how many visits it is
-  // expected to deliver (at minimum) to this class.
-  static const size_t kMaxVisitsToScore;
-
-  ScoredHistoryMatch();  // Required by STL.
-
-  // Creates a new match with a raw score calculated for the history item
-  // given in |row| with recent visits as indicated in |visits|.  First
-  // determines if the row qualifies by seeing if all of the terms in
-  // |terms_vector| occur in |row|.  If so, calculates a raw score.  This raw
-  // score is in part determined by whether the matches occur at word
-  // boundaries, the locations of which are stored in |word_starts|.  For some
-  // terms, it's appropriate to look for the word boundary within the term.
-  // For instance, the term ".net" should look for a word boundary at the "n".
-  // These offsets (".net" should have an offset of 1) come from
-  // |terms_to_word_starts_offsets|.  |history_client| is used to determine
-  // if the match's URL is referenced by any bookmarks, which can also affect
-  // the raw score.  The raw score allows the matches to be ordered and can be
-  // used to influence the final score calculated by the client of this index.
-  // If the row does not qualify the raw score will be 0.  |languages| is used
-  // to help parse/format the URL before looking for the terms.
-  ScoredHistoryMatch(const URLRow& row,
-                     const VisitInfoVector& visits,
-                     const std::string& languages,
-                     const base::string16& lower_string,
-                     const String16Vector& terms_vector,
-                     const WordStarts& terms_to_word_starts_offsets,
-                     const RowWordStarts& word_starts,
-                     const base::Time now,
-                     HistoryClient* history_client);
-  ~ScoredHistoryMatch();
-
-  // Compares two matches by score.  Functor supporting URLIndexPrivateData's
-  // HistoryItemsForTerms function.  Looks at particular fields within
-  // with url_info to make tie-breaking a bit smarter.
-  static bool MatchScoreGreater(const ScoredHistoryMatch& m1,
-                                const ScoredHistoryMatch& m2);
-
-  // Accessors:
-  int raw_score() const { return raw_score_; }
-  const TermMatches& url_matches() const { return url_matches_; }
-  const TermMatches& title_matches() const { return title_matches_; }
-  bool can_inline() const { return can_inline_; }
+  // Returns whether |url| is bookmarked which is used to affect the score. Must
+  // support being called multiple times.
+  typedef base::Callback<bool(const GURL& url)> IsBookmarkedCallback;
+
+  explicit ScoredHistoryMatchBuilderImpl(
+      const IsBookmarkedCallback& is_bookmarked);
+  ~ScoredHistoryMatchBuilderImpl() override;
+
+  // history::ScoredHistoryMatch implementation.
+  history::ScoredHistoryMatch Build(
+      const history::URLRow& row,
+      const history::VisitInfoVector& visits,
+      const std::string& languages,
+      const base::string16& lower_string,
+      const history::String16Vector& terms_vector,
+      const history::WordStarts& terms_to_word_starts_offsets,
+      const history::RowWordStarts& word_starts,
+      const base::Time now) const override;
 
   // Returns |term_matches| after removing all matches that are not at a
   // word break that are in the range [|start_pos|, |end_pos|).
   // start_pos == string::npos is treated as start_pos = length of string.
   // (In other words, no matches will be filtered.)
   // end_pos == string::npos is treated as end_pos = length of string.
-  static TermMatches FilterTermMatchesByWordStarts(
-      const TermMatches& term_matches,
-      const WordStarts& terms_to_word_starts_offsets,
-      const WordStarts& word_starts,
+  static history::TermMatches FilterTermMatchesByWordStarts(
+      const history::TermMatches& term_matches,
+      const history::WordStarts& terms_to_word_starts_offsets,
+      const history::WordStarts& word_starts,
       size_t start_pos,
       size_t end_pos);
 
  private:
-  friend class ScoredHistoryMatchTest;
-  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringBookmarks);
-  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringDiscountFrecency);
-  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringScheme);
-  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringTLD);
-
-  // The number of days of recency scores to precompute.
-  static const int kDaysToPrecomputeRecencyScoresFor;
-
-  // The number of raw term score buckets use; raw term scores
-  // greater this are capped at the score of the largest bucket.
-  static const int kMaxRawTermScore;
-
-  // Return a topicality score based on how many matches appear in the
-  // url and the page's title and where they are (e.g., at word
-  // boundaries).  Revises |url_matches_| and |title_matches_| in the
-  // process so they only reflect matches used for scoring.  (For
-  // instance, some mid-word matches are not given credit in scoring.)
-  float GetTopicalityScore(const int num_terms,
-                           const base::string16& cleaned_up_url,
-                           const WordStarts& terms_to_word_starts_offsets,
-                           const RowWordStarts& word_starts);
-
-  // Precalculates raw_term_score_to_topicality_score_, used in
-  // GetTopicalityScore().
-  static void FillInTermScoreToTopicalityScoreArray();
+  friend class ScoredHistoryMatchBuilderImplTest;
+  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchBuilderImplTest, ScoringBookmarks);
+  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchBuilderImplTest, ScoringScheme);
+  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchBuilderImplTest, ScoringTLD);
+
+  // Initialize ScoredHistoryMatchBuilderImpl statics.
+  void Init();
+
+  // Return a topicality score based on how many matches appear in the url and
+  // the page's title and where they are (e.g., at word boundaries).  Revises
+  // url_matches and title_matches of |scored_history_match| in the process so
+  // they only reflect matches used for scoring.  (For instance, some mid-word
+  // matches are not given credit in scoring.)
+  static float GetTopicalityScore(
+      const int num_terms,
+      const base::string16& cleaned_up_url,
+      const history::WordStarts& terms_to_word_starts_offsets,
+      const history::RowWordStarts& word_starts,
+      history::ScoredHistoryMatch* scored_history_match);
 
   // Returns a recency score based on |last_visit_days_ago|, which is
   // how many days ago the page was last visited.
   static float GetRecencyScore(int last_visit_days_ago);
 
-  // Pre-calculates days_ago_to_recency_numerator_, used in
-  // GetRecencyScore().
-  static void FillInDaysAgoToRecencyScoreArray();
-
   // Examines the first kMaxVisitsToScore and return a score (higher is
   // better) based the rate of visits, whether the page is bookmarked, and
   // how often those visits are typed navigations (i.e., explicitly
@@ -124,58 +95,12 @@ class ScoredHistoryMatch : public history::HistoryMatch {
   // recomputing it frequently.
   static float GetFrequency(const base::Time& now,
                             const bool bookmarked,
-                            const VisitInfoVector& visits);
+                            const history::VisitInfoVector& visits);
 
   // Combines the two component scores into a final score that's
   // an appropriate value to use as a relevancy score.
-  static float GetFinalRelevancyScore(
-      float topicality_score,
-      float frequency_score);
-
-  // Sets |also_do_hup_like_scoring_|,
-  // |max_assigned_score_for_non_inlineable_matches_|, |bookmark_value_|,
-  // |allow_tld_matches_|, and |allow_scheme_matches_| based on the field
-  // trial state.
-  static void Init();
-
-  // An interim score taking into consideration location and completeness
-  // of the match.
-  int raw_score_;
-
-  // Both these TermMatches contain the set of matches that are considered
-  // important.  At this time, that means they exclude mid-word matches
-  // except in the hostname of the URL.  (Technically, during early
-  // construction of ScoredHistoryMatch, they may contain all matches, but
-  // unimportant matches are eliminated by GetTopicalityScore(), called
-  // during construction.)
-  // Term matches within the URL.
-  TermMatches url_matches_;
-  // Term matches within the page title.
-  TermMatches title_matches_;
-
-  // True if this is a candidate for in-line autocompletion.
-  bool can_inline_;
-
-  // Pre-computed information to speed up calculating recency scores.
-  // |days_ago_to_recency_score_| is a simple array mapping how long
-  // ago a page was visited (in days) to the recency score we should
-  // assign it.  This allows easy lookups of scores without requiring
-  // math.  This is initialized upon first use of GetRecencyScore(),
-  // which calls FillInDaysAgoToRecencyScoreArray(),
-  static float* days_ago_to_recency_score_;
-
-  // Pre-computed information to speed up calculating topicality
-  // scores.  |raw_term_score_to_topicality_score_| is a simple array
-  // mapping how raw terms scores (a weighted sum of the number of
-  // hits for the term, weighted by how important the hit is:
-  // hostname, path, etc.) to the topicality score we should assign
-  // it.  This allows easy lookups of scores without requiring math.
-  // This is initialized upon first use of GetTopicalityScore(),
-  // which calls FillInTermScoreToTopicalityScoreArray().
-  static float* raw_term_score_to_topicality_score_;
-
-  // Used so we initialize static variables only once (on first use).
-  static bool initialized_;
+  static float GetFinalRelevancyScore(float topicality_score,
+                                      float frequency_score);
 
   // Untyped visits to bookmarked pages score this, compared to 1 for
   // untyped visits to non-bookmarked pages and 20 for typed visits.
@@ -187,22 +112,11 @@ class ScoredHistoryMatch : public history::HistoryMatch {
   // If true, we allow input terms to match in the scheme (e.g., http://).
   static bool allow_scheme_matches_;
 
-  // If true, assign raw scores to be max(whatever it normally would be,
-  // a score that's similar to the score HistoryURL provider would assign).
-  // This variable is set in the constructor by examining the field trial
-  // state.
-  static bool also_do_hup_like_scoring_;
-
-  // The maximum score that can be assigned to non-inlineable matches.
-  // This is useful because often we want inlineable matches to come
-  // first (even if they don't sometimes score as well as non-inlineable
-  // matches) because if a non-inlineable match comes first than all matches
-  // will get demoted later in HistoryQuickProvider to non-inlineable scores.
-  // Set to -1 to indicate no maximum score.
-  static int max_assigned_score_for_non_inlineable_matches_;
-};
-typedef std::vector<ScoredHistoryMatch> ScoredHistoryMatches;
+  // The IsBookmarkedCallback to use to check whether an URL is bookmarked. May
+  // be unset during testing.
+  IsBookmarkedCallback is_bookmarked_;
 
-}  // namespace history
+  DISALLOW_COPY_AND_ASSIGN(ScoredHistoryMatchBuilderImpl);
+};
 
-#endif  // CHROME_BROWSER_HISTORY_SCORED_HISTORY_MATCH_H_
+#endif  // CHROME_BROWSER_AUTOCOMPLETE_SCORED_HISTORY_MATCH_BUILDER_IMPL_H_