zero_suggest_provider.h revision 6d86b77056ed63eb6871182f42a9fd5f07550f90 
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.
4//
5// This file contains the zero-suggest autocomplete provider. This experimental
6// provider is invoked when the user focuses in the omnibox prior to editing,
7// and generates search query suggestions based on the current URL. To enable
8// this provider, point --experimental-zero-suggest-url-prefix at an
9// appropriate suggestion service.
10//
11// HUGE DISCLAIMER: This is just here for experimenting and will probably be
12// deleted entirely as we revise how suggestions work with the omnibox.
13
14#ifndef CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
15#define CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
16
17#include "base/basictypes.h"
18#include "base/compiler_specific.h"
19#include "base/memory/scoped_ptr.h"
20#include "chrome/browser/autocomplete/base_search_provider.h"
21#include "chrome/browser/autocomplete/search_provider.h"
22#include "components/metrics/proto/omnibox_event.pb.h"
23
24class TemplateURLService;
25
26namespace base {
27class ListValue;
28class Value;
29}
30
31namespace net {
32class URLFetcher;
33}
34
35namespace user_prefs {
36class PrefRegistrySyncable;
37}
38
39// Autocomplete provider for searches based on the current URL.
40//
41// The controller will call StartZeroSuggest when the user focuses in the
42// omnibox. After construction, the autocomplete controller repeatedly calls
43// Start() with some user input, each time expecting to receive an updated
44// set of matches.
45//
46// TODO(jered): Consider deleting this class and building this functionality
47// into SearchProvider after dogfood and after we break the association between
48// omnibox text and suggestions.
49class ZeroSuggestProvider : public BaseSearchProvider {
50 public:
51  // Creates and returns an instance of this provider.
52  static ZeroSuggestProvider* Create(AutocompleteProviderListener* listener,
53                                     Profile* profile);
54
55  // Registers a preference used to cache zero suggest results.
56  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
57
58  // AutocompleteProvider:
59  virtual void Start(const AutocompleteInput& input,
60                     bool minimal_changes) OVERRIDE;
61  virtual void DeleteMatch(const AutocompleteMatch& match) OVERRIDE;
62
63  // Sets |field_trial_triggered_| to false.
64  virtual void ResetSession() OVERRIDE;
65
66 protected:
67  // BaseSearchProvider:
68  virtual void ModifyProviderInfo(
69      metrics::OmniboxEventProto_ProviderInfo* provider_info) const OVERRIDE;
70
71 private:
72  ZeroSuggestProvider(AutocompleteProviderListener* listener,
73                      Profile* profile);
74
75  virtual ~ZeroSuggestProvider();
76
77  // BaseSearchProvider:
78  virtual bool StoreSuggestionResponse(const std::string& json_data,
79                                       const base::Value& parsed_data) OVERRIDE;
80  virtual const TemplateURL* GetTemplateURL(bool is_keyword) const OVERRIDE;
81  virtual const AutocompleteInput GetInput(bool is_keyword) const OVERRIDE;
82  virtual Results* GetResultsToFill(bool is_keyword) OVERRIDE;
83  virtual bool ShouldAppendExtraParams(
84      const SuggestResult& result) const OVERRIDE;
85  virtual void StopSuggest() OVERRIDE;
86  virtual void ClearAllResults() OVERRIDE;
87  virtual int GetDefaultResultRelevance() const OVERRIDE;
88  virtual void RecordDeletionResult(bool success) OVERRIDE;
89  virtual void LogFetchComplete(bool success, bool is_keyword) OVERRIDE;
90  virtual bool IsKeywordFetcher(const net::URLFetcher* fetcher) const OVERRIDE;
91  virtual void UpdateMatches() OVERRIDE;
92
93  // Adds AutocompleteMatches for each of the suggestions in |results| to
94  // |map|.
95  void AddSuggestResultsToMap(const SuggestResults& results, MatchMap* map);
96
97  // Returns an AutocompleteMatch for a navigational suggestion |navigation|.
98  AutocompleteMatch NavigationToMatch(const NavigationResult& navigation);
99
100  // Fetches zero-suggest suggestions by sending a request using |suggest_url|.
101  void Run(const GURL& suggest_url);
102
103  // Converts the parsed results to a set of AutocompleteMatches and adds them
104  // to |matches_|.  Also update the histograms for how many results were
105  // received.
106  void ConvertResultsToAutocompleteMatches();
107
108  // Returns an AutocompleteMatch for the current URL. The match should be in
109  // the top position so that pressing enter has the effect of reloading the
110  // page.
111  AutocompleteMatch MatchForCurrentURL();
112
113  // When the user is in the Most Visited field trial, we ask the TopSites
114  // service for the most visited URLs during Run().  It calls back to this
115  // function to return those |urls|.
116  void OnMostVisitedUrlsAvailable(const history::MostVisitedURLList& urls);
117
118  // Returns the relevance score for the verbatim result.
119  int GetVerbatimRelevance() const;
120
121  // Whether we can show zero suggest on |current_page_url| without
122  // sending |current_page_url| as a parameter to the server at |suggest_url|.
123  bool CanShowZeroSuggestWithoutSendingURL(const GURL& suggest_url,
124                                           const GURL& current_page_url) const;
125
126  // Checks whether we have a set of zero suggest results cached, and if so
127  // populates |matches_| with cached results.
128  void MaybeUseCachedSuggestions();
129
130  // Used to build default search engine URLs for suggested queries.
131  TemplateURLService* template_url_service_;
132
133  // The URL for which a suggestion fetch is pending.
134  std::string current_query_;
135
136  // The type of page the user is viewing (a search results page doing search
137  // term replacement, an arbitrary URL, etc.).
138  metrics::OmniboxEventProto::PageClassification current_page_classification_;
139
140  // Copy of OmniboxEditModel::permanent_text_.
141  base::string16 permanent_text_;
142
143  // Fetcher used to retrieve results.
144  scoped_ptr<net::URLFetcher> fetcher_;
145
146  // Suggestion for the current URL.
147  AutocompleteMatch current_url_match_;
148
149  // Contains suggest and navigation results as well as relevance parsed from
150  // the response for the most recent zero suggest input URL.
151  Results results_;
152
153  // Whether we are currently showing cached zero suggest results.
154  bool results_from_cache_;
155
156  history::MostVisitedURLList most_visited_urls_;
157
158  // For callbacks that may be run after destruction.
159  base::WeakPtrFactory<ZeroSuggestProvider> weak_ptr_factory_;
160
161  DISALLOW_COPY_AND_ASSIGN(ZeroSuggestProvider);
162};
163
164#endif  // CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
165