1// Copyright 2013 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#include "chrome/browser/ui/omnibox/omnibox_controller.h"
6
7#include "base/metrics/histogram.h"
8#include "chrome/browser/autocomplete/autocomplete_classifier.h"
9#include "chrome/browser/autocomplete/autocomplete_match.h"
10#include "chrome/browser/autocomplete/search_provider.h"
11#include "chrome/browser/net/predictor.h"
12#include "chrome/browser/predictors/autocomplete_action_predictor.h"
13#include "chrome/browser/prerender/prerender_field_trial.h"
14#include "chrome/browser/prerender/prerender_manager.h"
15#include "chrome/browser/prerender/prerender_manager_factory.h"
16#include "chrome/browser/profiles/profile.h"
17#include "chrome/browser/search/search.h"
18#include "chrome/browser/ui/omnibox/omnibox_edit_controller.h"
19#include "chrome/browser/ui/omnibox/omnibox_edit_model.h"
20#include "chrome/browser/ui/omnibox/omnibox_popup_model.h"
21#include "chrome/browser/ui/omnibox/omnibox_popup_view.h"
22#include "chrome/common/instant_types.h"
23#include "extensions/common/constants.h"
24#include "ui/gfx/rect.h"
25
26namespace {
27
28// Returns the AutocompleteMatch that the InstantController should prefetch, if
29// any.
30//
31// The SearchProvider may mark some suggestions to be prefetched based on
32// instructions from the suggest server. If such a match ranks sufficiently
33// highly or if kAllowPrefetchNonDefaultMatch field trial is enabled, we'll
34// return it.
35//
36// If the kAllowPrefetchNonDefaultMatch field trial is enabled we return the
37// prefetch suggestion even if it is not the default match. Otherwise we only
38// care about matches that are the default or the very first entry in the
39// dropdown (which can happen for non-default matches only if we're hiding a top
40// verbatim match) or the second entry in the dropdown (which can happen for
41// non-default matches when a top verbatim match is shown); for other matches,
42// we think the likelihood of the user selecting them is low enough that
43// prefetching isn't worth doing.
44const AutocompleteMatch* GetMatchToPrefetch(const AutocompleteResult& result) {
45  if (chrome::ShouldAllowPrefetchNonDefaultMatch()) {
46    const AutocompleteResult::const_iterator prefetch_match = std::find_if(
47        result.begin(), result.end(), SearchProvider::ShouldPrefetch);
48    return prefetch_match != result.end() ? &(*prefetch_match) : NULL;
49  }
50
51  // If the default match should be prefetched, do that.
52  const AutocompleteResult::const_iterator default_match(
53      result.default_match());
54  if ((default_match != result.end()) &&
55      SearchProvider::ShouldPrefetch(*default_match))
56    return &(*default_match);
57
58  // Otherwise, if the top match is a verbatim match and the very next match
59  // is prefetchable, fetch that.
60  if ((result.ShouldHideTopMatch() ||
61       result.TopMatchIsStandaloneVerbatimMatch()) &&
62      (result.size() > 1) &&
63      SearchProvider::ShouldPrefetch(result.match_at(1)))
64    return &result.match_at(1);
65
66  return NULL;
67}
68
69}  // namespace
70
71OmniboxController::OmniboxController(OmniboxEditModel* omnibox_edit_model,
72                                     Profile* profile)
73    : omnibox_edit_model_(omnibox_edit_model),
74      profile_(profile),
75      popup_(NULL),
76      autocomplete_controller_(new AutocompleteController(profile, this,
77          AutocompleteClassifier::kDefaultOmniboxProviders)) {
78}
79
80OmniboxController::~OmniboxController() {
81}
82
83void OmniboxController::StartAutocomplete(
84    const AutocompleteInput& input) const {
85  ClearPopupKeywordMode();
86  popup_->SetHoveredLine(OmniboxPopupModel::kNoMatch);
87
88  // We don't explicitly clear OmniboxPopupModel::manually_selected_match, as
89  // Start ends up invoking OmniboxPopupModel::OnResultChanged which clears it.
90  autocomplete_controller_->Start(input);
91}
92
93void OmniboxController::OnResultChanged(bool default_match_changed) {
94  const bool was_open = popup_->IsOpen();
95  if (default_match_changed) {
96    // The default match has changed, we need to let the OmniboxEditModel know
97    // about new inline autocomplete text (blue highlight).
98    const AutocompleteResult::const_iterator match(result().default_match());
99    if (match != result().end()) {
100      current_match_ = *match;
101      if (!prerender::IsOmniboxEnabled(profile_))
102        DoPreconnect(*match);
103      omnibox_edit_model_->OnCurrentMatchChanged();
104    } else {
105      InvalidateCurrentMatch();
106      popup_->OnResultChanged();
107      omnibox_edit_model_->OnPopupDataChanged(base::string16(), NULL,
108                                              base::string16(), false);
109    }
110  } else {
111    popup_->OnResultChanged();
112  }
113
114  if (!popup_->IsOpen() && was_open) {
115    // Accept the temporary text as the user text, because it makes little sense
116    // to have temporary text when the popup is closed.
117    omnibox_edit_model_->AcceptTemporaryTextAsUserText();
118  }
119
120  if (chrome::IsInstantExtendedAPIEnabled() &&
121     ((default_match_changed && result().default_match() != result().end()) ||
122      (chrome::ShouldAllowPrefetchNonDefaultMatch() && !result().empty()))) {
123    InstantSuggestion prefetch_suggestion;
124    const AutocompleteMatch* match_to_prefetch = GetMatchToPrefetch(result());
125    if (match_to_prefetch) {
126      prefetch_suggestion.text = match_to_prefetch->contents;
127      prefetch_suggestion.metadata =
128          SearchProvider::GetSuggestMetadata(*match_to_prefetch);
129    }
130    // Send the prefetch suggestion unconditionally to the InstantPage. If
131    // there is no suggestion to prefetch, we need to send a blank query to
132    // clear the prefetched results.
133    omnibox_edit_model_->SetSuggestionToPrefetch(prefetch_suggestion);
134  }
135}
136
137void OmniboxController::InvalidateCurrentMatch() {
138  current_match_ = AutocompleteMatch();
139}
140
141void OmniboxController::ClearPopupKeywordMode() const {
142  if (popup_->IsOpen() &&
143      popup_->selected_line_state() == OmniboxPopupModel::KEYWORD)
144    popup_->SetSelectedLineState(OmniboxPopupModel::NORMAL);
145}
146
147void OmniboxController::DoPreconnect(const AutocompleteMatch& match) {
148  if (!match.destination_url.SchemeIs(extensions::kExtensionScheme)) {
149    // Warm up DNS Prefetch cache, or preconnect to a search service.
150    UMA_HISTOGRAM_ENUMERATION("Autocomplete.MatchType", match.type,
151                              AutocompleteMatchType::NUM_TYPES);
152    if (profile_->GetNetworkPredictor()) {
153      profile_->GetNetworkPredictor()->AnticipateOmniboxUrl(
154          match.destination_url,
155          predictors::AutocompleteActionPredictor::IsPreconnectable(match));
156    }
157    // We could prefetch the alternate nav URL, if any, but because there
158    // can be many of these as a user types an initial series of characters,
159    // the OS DNS cache could suffer eviction problems for minimal gain.
160  }
161}
162