chrome/browser/autocomplete/zero_suggest_provider.h

   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.
   8
   9 #ifndef CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
  10 #define CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
  11
  12 #include "base/basictypes.h"
  13 #include "base/compiler_specific.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "components/history/core/browser/history_types.h"
  16 #include "components/metrics/proto/omnibox_event.pb.h"
  17 #include "components/omnibox/base_search_provider.h"
  18 #include "components/omnibox/search_provider.h"
  19 #include "net/url_request/url_fetcher_delegate.h"
  20
  21 class AutocompleteProviderListener;
  22 class Profile;
  23 class TemplateURLService;
  24
  25 namespace base {
  26 class ListValue;
  27 class Value;
  28 }
  29
  30 namespace net {
  31 class URLFetcher;
  32 }
  33
  34 namespace user_prefs {
  35 class PrefRegistrySyncable;
  36 }
  37
  38 // Autocomplete provider for searches based on the current URL.
  39 //
  40 // The controller will call Start() with |on_focus| set when the user focuses
  41 // the omnibox. After construction, the autocomplete controller repeatedly calls
  42 // Start() with some user input, each time expecting to receive an updated set
  43 // of matches.
  44 //
  45 // TODO(jered): Consider deleting this class and building this functionality
  46 // into SearchProvider after dogfood and after we break the association between
  47 // omnibox text and suggestions.
  48 class ZeroSuggestProvider : public BaseSearchProvider,
  49                             public net::URLFetcherDelegate {
  50  public:
  51   // Creates and returns an instance of this provider.
  52   static ZeroSuggestProvider* Create(AutocompleteProviderListener* listener,
  53                                      TemplateURLService* template_url_service,
  54                                      Profile* profile);
  55
  56   // Registers a preference used to cache zero suggest results.
  57   static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
  58
  59   // AutocompleteProvider:
  60   void Start(const AutocompleteInput& input,
  61              bool minimal_changes,
  62              bool called_due_to_focus) override;
  63   void Stop(bool clear_cached_results,
  64             bool due_to_user_inactivity) override;
  65   void DeleteMatch(const AutocompleteMatch& match) override;
  66   void AddProviderInfo(ProvidersInfo* provider_info) const override;
  67
  68   // Sets |field_trial_triggered_| to false.
  69   void ResetSession() override;
  70
  71  private:
  72   ZeroSuggestProvider(AutocompleteProviderListener* listener,
  73                       TemplateURLService* template_url_service,
  74                       Profile* profile);
  75
  76   ~ZeroSuggestProvider() override;
  77
  78   // BaseSearchProvider:
  79   const TemplateURL* GetTemplateURL(bool is_keyword) const override;
  80   const AutocompleteInput GetInput(bool is_keyword) const override;
  81   bool ShouldAppendExtraParams(
  82       const SearchSuggestionParser::SuggestResult& result) const override;
  83   void RecordDeletionResult(bool success) override;
  84
  85   // net::URLFetcherDelegate:
  86   void OnURLFetchComplete(const net::URLFetcher* source) override;
  87
  88   // Optionally, cache the received |json_data| and return true if we want
  89   // to stop processing results at this point. The |parsed_data| is the parsed
  90   // version of |json_data| used to determine if we received an empty result.
  91   bool StoreSuggestionResponse(const std::string& json_data,
  92                                const base::Value& parsed_data);
  93
  94   // Adds AutocompleteMatches for each of the suggestions in |results| to
  95   // |map|.
  96   void AddSuggestResultsToMap(
  97       const SearchSuggestionParser::SuggestResults& results,
  98       MatchMap* map);
  99
 100   // Returns an AutocompleteMatch for a navigational suggestion |navigation|.
 101   AutocompleteMatch NavigationToMatch(
 102       const SearchSuggestionParser::NavigationResult& navigation);
 103
 104   // Fetches zero-suggest suggestions by sending a request using |suggest_url|.
 105   void Run(const GURL& suggest_url);
 106
 107   // Converts the parsed results to a set of AutocompleteMatches and adds them
 108   // to |matches_|.  Also update the histograms for how many results were
 109   // received.
 110   void ConvertResultsToAutocompleteMatches();
 111
 112   // Returns an AutocompleteMatch for the current URL. The match should be in
 113   // the top position so that pressing enter has the effect of reloading the
 114   // page.
 115   AutocompleteMatch MatchForCurrentURL();
 116
 117   // When the user is in the Most Visited field trial, we ask the TopSites
 118   // service for the most visited URLs during Run().  It calls back to this
 119   // function to return those |urls|.
 120   void OnMostVisitedUrlsAvailable(const history::MostVisitedURLList& urls);
 121
 122   // Returns the relevance score for the verbatim result.
 123   int GetVerbatimRelevance() const;
 124
 125   // Whether we can show zero suggest without sending |current_page_url| to
 126   // |suggest_url| search provider. Also checks that other conditions for
 127   // non-contextual zero suggest are satisfied.
 128   bool ShouldShowNonContextualZeroSuggest(const GURL& suggest_url,
 129                                           const GURL& current_page_url) const;
 130
 131   // Checks whether we have a set of zero suggest results cached, and if so
 132   // populates |matches_| with cached results.
 133   void MaybeUseCachedSuggestions();
 134
 135   AutocompleteProviderListener* listener_;
 136   Profile* profile_;
 137
 138   // The URL for which a suggestion fetch is pending.
 139   std::string current_query_;
 140
 141   // The type of page the user is viewing (a search results page doing search
 142   // term replacement, an arbitrary URL, etc.).
 143   metrics::OmniboxEventProto::PageClassification current_page_classification_;
 144
 145   // Copy of OmniboxEditModel::permanent_text_.
 146   base::string16 permanent_text_;
 147
 148   // Fetcher used to retrieve results.
 149   scoped_ptr<net::URLFetcher> fetcher_;
 150
 151   // Suggestion for the current URL.
 152   AutocompleteMatch current_url_match_;
 153
 154   // Contains suggest and navigation results as well as relevance parsed from
 155   // the response for the most recent zero suggest input URL.
 156   SearchSuggestionParser::Results results_;
 157
 158   // Whether we are currently showing cached zero suggest results.
 159   bool results_from_cache_;
 160
 161   history::MostVisitedURLList most_visited_urls_;
 162
 163   // Whether we are waiting for a most visited visited urls callback to run.
 164   bool waiting_for_most_visited_urls_request_;
 165
 166   // For callbacks that may be run after destruction.
 167   base::WeakPtrFactory<ZeroSuggestProvider> weak_ptr_factory_;
 168
 169   DISALLOW_COPY_AND_ASSIGN(ZeroSuggestProvider);
 170 };
 171
 172 #endif  // CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_