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