| // Copyright 2016 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef COMPONENTS_OMNIBOX_BROWSER_MATCH_COMPARE_H_ |
| #define COMPONENTS_OMNIBOX_BROWSER_MATCH_COMPARE_H_ |
| |
| #include "components/omnibox/browser/omnibox_field_trial.h" |
| |
| // This class implements a special version of AutocompleteMatch::MoreRelevant |
| // that allows matches of particular types to be demoted in AutocompleteResult. |
| template <class Match> |
| class CompareWithDemoteByType { |
| public: |
| CompareWithDemoteByType( |
| metrics::OmniboxEventProto::PageClassification page_classification) { |
| OmniboxFieldTrial::GetDemotionsByType(page_classification, &demotions_); |
| } |
| |
| // Returns the relevance score of |match| demoted appropriately by |
| // |demotions_by_type_|. |
| int GetDemotedRelevance(const Match& match) const { |
| OmniboxFieldTrial::DemotionMultipliers::const_iterator demotion_it = |
| demotions_.find(match.type); |
| return (demotion_it == demotions_.end()) |
| ? match.relevance |
| : (match.relevance * demotion_it->second); |
| } |
| |
| // Comparison function. |
| bool operator()(const Match& elem1, const Match& elem2) { |
| // Compute demoted relevance scores for each match. |
| const int demoted_relevance1 = GetDemotedRelevance(elem1); |
| const int demoted_relevance2 = GetDemotedRelevance(elem2); |
| // For equal-relevance matches, we sort alphabetically, so that providers |
| // who return multiple elements at the same priority get a "stable" sort |
| // across multiple updates. |
| return (demoted_relevance1 == demoted_relevance2) |
| ? (elem1.contents < elem2.contents) |
| : (demoted_relevance1 > demoted_relevance2); |
| } |
| |
| private: |
| OmniboxFieldTrial::DemotionMultipliers demotions_; |
| }; |
| |
| template <class Match> |
| class DestinationSort { |
| public: |
| DestinationSort( |
| metrics::OmniboxEventProto::PageClassification page_classification) |
| : demote_by_type_(page_classification) {} |
| bool operator()(const Match& elem1, const Match& elem2) { |
| // Sort identical destination_urls together. |
| // Place the most relevant matches first, so that when we call |
| // std::unique(), these are the ones that get preserved. |
| return (elem1.stripped_destination_url == elem2.stripped_destination_url) |
| ? demote_by_type_(elem1, elem2) |
| : (elem1.stripped_destination_url < |
| elem2.stripped_destination_url); |
| } |
| |
| private: |
| CompareWithDemoteByType<Match> demote_by_type_; |
| }; |
| |
| #endif // COMPONENTS_OMNIBOX_BROWSER_MATCH_COMPARE_H_ |