Componentize AutocompleteController and its supporting cast

chrome/browser/autocomplete/zero_suggest_provider.h

-// Copyright (c) 2012 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.
-//
-// This file contains the zero-suggest autocomplete provider. This experimental
-// provider is invoked when the user focuses in the omnibox prior to editing,
-// and generates search query suggestions based on the current URL.
-
-#ifndef CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
-#define CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "base/memory/scoped_ptr.h"
-#include "components/history/core/browser/history_types.h"
-#include "components/metrics/proto/omnibox_event.pb.h"
-#include "components/omnibox/base_search_provider.h"
-#include "components/omnibox/search_provider.h"
-#include "net/url_request/url_fetcher_delegate.h"
-
-class AutocompleteProviderListener;
-
-namespace base {
-class ListValue;
-class Value;
-}
-
-namespace net {
-class URLFetcher;
-}
-
-namespace user_prefs {
-class PrefRegistrySyncable;
-}
-
-// Autocomplete provider for searches based on the current URL.
-//
-// The controller will call Start() with |on_focus| set when the user focuses
-// the omnibox. After construction, the autocomplete controller repeatedly calls
-// Start() with some user input, each time expecting to receive an updated set
-// of matches.
-//
-// TODO(jered): Consider deleting this class and building this functionality
-// into SearchProvider after dogfood and after we break the association between
-// omnibox text and suggestions.
-class ZeroSuggestProvider : public BaseSearchProvider,
-                            public net::URLFetcherDelegate {
- public:
-  // Creates and returns an instance of this provider.
-  static ZeroSuggestProvider* Create(AutocompleteProviderClient* client,
-                                     AutocompleteProviderListener* listener);
-
-  // Registers a preference used to cache zero suggest results.
-  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
-
-  // AutocompleteProvider:
-  void Start(const AutocompleteInput& input, bool minimal_changes) override;
-  void Stop(bool clear_cached_results,
-            bool due_to_user_inactivity) override;
-  void DeleteMatch(const AutocompleteMatch& match) override;
-  void AddProviderInfo(ProvidersInfo* provider_info) const override;
-
-  // Sets |field_trial_triggered_| to false.
-  void ResetSession() override;
-
- private:
-  ZeroSuggestProvider(AutocompleteProviderClient* client,
-                      AutocompleteProviderListener* listener);
-
-  ~ZeroSuggestProvider() override;
-
-  // BaseSearchProvider:
-  const TemplateURL* GetTemplateURL(bool is_keyword) const override;
-  const AutocompleteInput GetInput(bool is_keyword) const override;
-  bool ShouldAppendExtraParams(
-      const SearchSuggestionParser::SuggestResult& result) const override;
-  void RecordDeletionResult(bool success) override;
-
-  // net::URLFetcherDelegate:
-  void OnURLFetchComplete(const net::URLFetcher* source) override;
-
-  // Optionally, cache the received |json_data| and return true if we want
-  // to stop processing results at this point. The |parsed_data| is the parsed
-  // version of |json_data| used to determine if we received an empty result.
-  bool StoreSuggestionResponse(const std::string& json_data,
-                               const base::Value& parsed_data);
-
-  // Adds AutocompleteMatches for each of the suggestions in |results| to
-  // |map|.
-  void AddSuggestResultsToMap(
-      const SearchSuggestionParser::SuggestResults& results,
-      MatchMap* map);
-
-  // Returns an AutocompleteMatch for a navigational suggestion |navigation|.
-  AutocompleteMatch NavigationToMatch(
-      const SearchSuggestionParser::NavigationResult& navigation);
-
-  // Fetches zero-suggest suggestions by sending a request using |suggest_url|.
-  void Run(const GURL& suggest_url);
-
-  // Converts the parsed results to a set of AutocompleteMatches and adds them
-  // to |matches_|.  Also update the histograms for how many results were
-  // received.
-  void ConvertResultsToAutocompleteMatches();
-
-  // Returns an AutocompleteMatch for the current URL. The match should be in
-  // the top position so that pressing enter has the effect of reloading the
-  // page.
-  AutocompleteMatch MatchForCurrentURL();
-
-  // When the user is in the Most Visited field trial, we ask the TopSites
-  // service for the most visited URLs during Run().  It calls back to this
-  // function to return those |urls|.
-  void OnMostVisitedUrlsAvailable(const history::MostVisitedURLList& urls);
-
-  // Returns the relevance score for the verbatim result.
-  int GetVerbatimRelevance() const;
-
-  // Whether we can show zero suggest without sending |current_page_url| to
-  // |suggest_url| search provider. Also checks that other conditions for
-  // non-contextual zero suggest are satisfied.
-  bool ShouldShowNonContextualZeroSuggest(const GURL& suggest_url,
-                                          const GURL& current_page_url) const;
-
-  // Checks whether we have a set of zero suggest results cached, and if so
-  // populates |matches_| with cached results.
-  void MaybeUseCachedSuggestions();
-
-  AutocompleteProviderListener* listener_;
-
-  // The URL for which a suggestion fetch is pending.
-  std::string current_query_;
-
-  // The type of page the user is viewing (a search results page doing search
-  // term replacement, an arbitrary URL, etc.).
-  metrics::OmniboxEventProto::PageClassification current_page_classification_;
-
-  // Copy of OmniboxEditModel::permanent_text_.
-  base::string16 permanent_text_;
-
-  // Fetcher used to retrieve results.
-  scoped_ptr<net::URLFetcher> fetcher_;
-
-  // Suggestion for the current URL.
-  AutocompleteMatch current_url_match_;
-
-  // Contains suggest and navigation results as well as relevance parsed from
-  // the response for the most recent zero suggest input URL.
-  SearchSuggestionParser::Results results_;
-
-  // Whether we are currently showing cached zero suggest results.
-  bool results_from_cache_;
-
-  history::MostVisitedURLList most_visited_urls_;
-
-  // Whether we are waiting for a most visited visited urls callback to run.
-  bool waiting_for_most_visited_urls_request_;
-
-  // For callbacks that may be run after destruction.
-  base::WeakPtrFactory<ZeroSuggestProvider> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(ZeroSuggestProvider);
-};
-
-#endif  // CHROME_BROWSER_AUTOCOMPLETE_ZERO_SUGGEST_PROVIDER_H_