chrome/browser/autocomplete/autocomplete_controller.cc

   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 #include "chrome/browser/autocomplete/autocomplete_controller.h"
   6
   7 #include <set>
   8 #include <string>
   9
  10 #include "base/format_macros.h"
  11 #include "base/logging.h"
  12 #include "base/metrics/histogram.h"
  13 #include "base/strings/string_number_conversions.h"
  14 #include "base/strings/stringprintf.h"
  15 #include "base/time/time.h"
  16 #include "chrome/browser/autocomplete/autocomplete_controller_delegate.h"
  17 #include "chrome/browser/autocomplete/bookmark_provider.h"
  18 #include "chrome/browser/autocomplete/builtin_provider.h"
  19 #include "chrome/browser/autocomplete/chrome_autocomplete_provider_client.h"
  20 #include "chrome/browser/autocomplete/history_quick_provider.h"
  21 #include "chrome/browser/autocomplete/history_url_provider.h"
  22 #include "chrome/browser/autocomplete/shortcuts_provider.h"
  23 #include "chrome/browser/autocomplete/zero_suggest_provider.h"
  24 #include "chrome/browser/chrome_notification_types.h"
  25 #include "components/omnibox/keyword_provider.h"
  26 #include "components/omnibox/omnibox_field_trial.h"
  27 #include "components/omnibox/search_provider.h"
  28 #include "components/search_engines/template_url.h"
  29 #include "components/search_engines/template_url_service.h"
  30 #include "content/public/browser/notification_service.h"
  31 #include "grit/components_strings.h"
  32 #include "ui/base/l10n/l10n_util.h"
  33
  34 #if defined(ENABLE_EXTENSIONS)
  35 #include "chrome/browser/autocomplete/keyword_extensions_delegate_impl.h"
  36 #endif
  37
  38 namespace {
  39
  40 // Converts the given match to a type (and possibly subtype) based on the AQS
  41 // specification. For more details, see
  42 // http://goto.google.com/binary-clients-logging.
  43 void AutocompleteMatchToAssistedQuery(
  44     const AutocompleteMatch::Type& match,
  45     const AutocompleteProvider* provider,
  46     size_t* type,
  47     size_t* subtype) {
  48   // This type indicates a native chrome suggestion.
  49   *type = 69;
  50   // Default value, indicating no subtype.
  51   *subtype = base::string16::npos;
  52
  53   // If provider is TYPE_ZERO_SUGGEST, set the subtype accordingly.
  54   // Type will be set in the switch statement below where we'll enter one of
  55   // SEARCH_SUGGEST or NAVSUGGEST. This subtype indicates context-aware zero
  56   // suggest.
  57   if (provider &&
  58       (provider->type() == AutocompleteProvider::TYPE_ZERO_SUGGEST) &&
  59       (match != AutocompleteMatchType::SEARCH_SUGGEST_PERSONALIZED)) {
  60     DCHECK((match == AutocompleteMatchType::SEARCH_SUGGEST) ||
  61            (match == AutocompleteMatchType::NAVSUGGEST));
  62     *subtype = 66;
  63   }
  64
  65   switch (match) {
  66     case AutocompleteMatchType::SEARCH_SUGGEST: {
  67       // Do not set subtype here; subtype may have been set above.
  68       *type = 0;
  69       return;
  70     }
  71     case AutocompleteMatchType::SEARCH_SUGGEST_ENTITY: {
  72       *subtype = 46;
  73       return;
  74     }
  75     case AutocompleteMatchType::SEARCH_SUGGEST_INFINITE: {
  76       *subtype = 33;
  77       return;
  78     }
  79     case AutocompleteMatchType::SEARCH_SUGGEST_PERSONALIZED: {
  80       *subtype = 39;
  81       return;
  82     }
  83     case AutocompleteMatchType::SEARCH_SUGGEST_PROFILE: {
  84       *subtype = 44;
  85       return;
  86     }
  87     case AutocompleteMatchType::SEARCH_SUGGEST_ANSWER: {
  88       *subtype = 70;
  89       return;
  90     }
  91     case AutocompleteMatchType::NAVSUGGEST: {
  92       // Do not set subtype here; subtype may have been set above.
  93       *type = 5;
  94       return;
  95     }
  96     case AutocompleteMatchType::SEARCH_WHAT_YOU_TYPED: {
  97       *subtype = 57;
  98       return;
  99     }
 100     case AutocompleteMatchType::URL_WHAT_YOU_TYPED: {
 101       *subtype = 58;
 102       return;
 103     }
 104     case AutocompleteMatchType::SEARCH_HISTORY: {
 105       *subtype = 59;
 106       return;
 107     }
 108     case AutocompleteMatchType::HISTORY_URL: {
 109       *subtype = 60;
 110       return;
 111     }
 112     case AutocompleteMatchType::HISTORY_TITLE: {
 113       *subtype = 61;
 114       return;
 115     }
 116     case AutocompleteMatchType::HISTORY_BODY: {
 117       *subtype = 62;
 118       return;
 119     }
 120     case AutocompleteMatchType::HISTORY_KEYWORD: {
 121       *subtype = 63;
 122       return;
 123     }
 124     case AutocompleteMatchType::BOOKMARK_TITLE: {
 125       *subtype = 65;
 126       return;
 127     }
 128     case AutocompleteMatchType::NAVSUGGEST_PERSONALIZED: {
 129       *subtype = 39;
 130       return;
 131     }
 132     default: {
 133       // This value indicates a native chrome suggestion with no named subtype
 134       // (yet).
 135       *subtype = 64;
 136     }
 137   }
 138 }
 139
 140 // Appends available autocompletion of the given type, subtype, and number to
 141 // the existing available autocompletions string, encoding according to the
 142 // spec.
 143 void AppendAvailableAutocompletion(size_t type,
 144                                    size_t subtype,
 145                                    int count,
 146                                    std::string* autocompletions) {
 147   if (!autocompletions->empty())
 148     autocompletions->append("j");
 149   base::StringAppendF(autocompletions, "%" PRIuS, type);
 150   // Subtype is optional - base::string16::npos indicates no subtype.
 151   if (subtype != base::string16::npos)
 152     base::StringAppendF(autocompletions, "i%" PRIuS, subtype);
 153   if (count > 1)
 154     base::StringAppendF(autocompletions, "l%d", count);
 155 }
 156
 157 // Returns whether the autocompletion is trivial enough that we consider it
 158 // an autocompletion for which the omnibox autocompletion code did not add
 159 // any value.
 160 bool IsTrivialAutocompletion(const AutocompleteMatch& match) {
 161   return match.type == AutocompleteMatchType::SEARCH_WHAT_YOU_TYPED ||
 162       match.type == AutocompleteMatchType::URL_WHAT_YOU_TYPED ||
 163       match.type == AutocompleteMatchType::SEARCH_OTHER_ENGINE;
 164 }
 165
 166 // Whether this autocomplete match type supports custom descriptions.
 167 bool AutocompleteMatchHasCustomDescription(const AutocompleteMatch& match) {
 168   return match.type == AutocompleteMatchType::SEARCH_SUGGEST_ENTITY ||
 169       match.type == AutocompleteMatchType::SEARCH_SUGGEST_PROFILE;
 170 }
 171
 172 }  // namespace
 173
 174 AutocompleteController::AutocompleteController(
 175     Profile* profile,
 176     TemplateURLService* template_url_service,
 177     AutocompleteControllerDelegate* delegate,
 178     int provider_types)
 179     : delegate_(delegate),
 180       history_url_provider_(NULL),
 181       keyword_provider_(NULL),
 182       search_provider_(NULL),
 183       zero_suggest_provider_(NULL),
 184       stop_timer_duration_(OmniboxFieldTrial::StopTimerFieldTrialDuration()),
 185       done_(true),
 186       in_start_(false),
 187       template_url_service_(template_url_service) {
 188   provider_types &= ~OmniboxFieldTrial::GetDisabledProviderTypes();
 189   if (provider_types & AutocompleteProvider::TYPE_BOOKMARK)
 190     providers_.push_back(new BookmarkProvider(profile));
 191   if (provider_types & AutocompleteProvider::TYPE_BUILTIN)
 192     providers_.push_back(new BuiltinProvider());
 193   if (provider_types & AutocompleteProvider::TYPE_HISTORY_QUICK)
 194     providers_.push_back(new HistoryQuickProvider(profile));
 195   if (provider_types & AutocompleteProvider::TYPE_HISTORY_URL) {
 196     history_url_provider_ = new HistoryURLProvider(this, profile);
 197     providers_.push_back(history_url_provider_);
 198   }
 199   // "Tab to search" can be used on all platforms other than Android.
 200 #if !defined(OS_ANDROID)
 201   if (provider_types & AutocompleteProvider::TYPE_KEYWORD) {
 202     keyword_provider_ = new KeywordProvider(this, template_url_service);
 203 #if defined(ENABLE_EXTENSIONS)
 204     keyword_provider_->set_extensions_delegate(
 205         scoped_ptr<KeywordExtensionsDelegate>(
 206             new KeywordExtensionsDelegateImpl(profile, keyword_provider_)));
 207 #endif
 208     providers_.push_back(keyword_provider_);
 209   }
 210 #endif
 211   if (provider_types & AutocompleteProvider::TYPE_SEARCH) {
 212     search_provider_ = new SearchProvider(
 213         this, template_url_service, scoped_ptr<AutocompleteProviderClient>(
 214             new ChromeAutocompleteProviderClient(profile)));
 215     providers_.push_back(search_provider_);
 216   }
 217   if (provider_types & AutocompleteProvider::TYPE_SHORTCUTS)
 218     providers_.push_back(new ShortcutsProvider(profile));
 219   if (provider_types & AutocompleteProvider::TYPE_ZERO_SUGGEST) {
 220     zero_suggest_provider_ = ZeroSuggestProvider::Create(
 221         this, template_url_service, profile);
 222     if (zero_suggest_provider_)
 223       providers_.push_back(zero_suggest_provider_);
 224   }
 225 }
 226
 227 AutocompleteController::~AutocompleteController() {
 228   // The providers may have tasks outstanding that hold refs to them.  We need
 229   // to ensure they won't call us back if they outlive us.  (Practically,
 230   // calling Stop() should also cancel those tasks and make it so that we hold
 231   // the only refs.)  We also don't want to bother notifying anyone of our
 232   // result changes here, because the notification observer is in the midst of
 233   // shutdown too, so we don't ask Stop() to clear |result_| (and notify).
 234   result_.Reset();  // Not really necessary.
 235   Stop(false);
 236 }
 237
 238 void AutocompleteController::Start(const AutocompleteInput& input) {
 239   const base::string16 old_input_text(input_.text());
 240   const bool old_want_asynchronous_matches = input_.want_asynchronous_matches();
 241   input_ = input;
 242
 243   // See if we can avoid rerunning autocomplete when the query hasn't changed
 244   // much.  When the user presses or releases the ctrl key, the desired_tld
 245   // changes, and when the user finishes an IME composition, inline autocomplete
 246   // may no longer be prevented.  In both these cases the text itself hasn't
 247   // changed since the last query, and some providers can do much less work (and
 248   // get matches back more quickly).  Taking advantage of this reduces flicker.
 249   //
 250   // NOTE: This comes after constructing |input_| above since that construction
 251   // can change the text string (e.g. by stripping off a leading '?').
 252   const bool minimal_changes = (input_.text() == old_input_text) &&
 253       (input_.want_asynchronous_matches() == old_want_asynchronous_matches);
 254
 255   expire_timer_.Stop();
 256   stop_timer_.Stop();
 257
 258   // Start the new query.
 259   in_start_ = true;
 260   base::TimeTicks start_time = base::TimeTicks::Now();
 261   for (Providers::iterator i(providers_.begin()); i != providers_.end(); ++i) {
 262     // TODO(mpearson): Remove timing code once bugs 178705 / 237703 / 168933
 263     // are resolved.
 264     base::TimeTicks provider_start_time = base::TimeTicks::Now();
 265
 266     // Call Start() on ZeroSuggestProvider with an INVALID AutocompleteInput
 267     // to clear out zero-suggest |matches_|.
 268     if (i->get() == zero_suggest_provider_)
 269       (*i)->Start(AutocompleteInput(), minimal_changes);
 270     else
 271       (*i)->Start(input_, minimal_changes);
 272
 273     if (!input.want_asynchronous_matches())
 274       DCHECK((*i)->done());
 275     base::TimeTicks provider_end_time = base::TimeTicks::Now();
 276     std::string name = std::string("Omnibox.ProviderTime.") + (*i)->GetName();
 277     base::HistogramBase* counter = base::Histogram::FactoryGet(
 278         name, 1, 5000, 20, base::Histogram::kUmaTargetedHistogramFlag);
 279     counter->Add(static_cast<int>(
 280         (provider_end_time - provider_start_time).InMilliseconds()));
 281   }
 282   if (input.want_asynchronous_matches() && (input.text().length() < 6)) {
 283     base::TimeTicks end_time = base::TimeTicks::Now();
 284     std::string name = "Omnibox.QueryTime." + base::IntToString(
 285         input.text().length());
 286     base::HistogramBase* counter = base::Histogram::FactoryGet(
 287         name, 1, 1000, 50, base::Histogram::kUmaTargetedHistogramFlag);
 288     counter->Add(static_cast<int>((end_time - start_time).InMilliseconds()));
 289   }
 290   in_start_ = false;
 291   CheckIfDone();
 292   // The second true forces saying the default match has changed.
 293   // This triggers the edit model to update things such as the inline
 294   // autocomplete state.  In particular, if the user has typed a key
 295   // since the last notification, and we're now re-running
 296   // autocomplete, then we need to update the inline autocompletion
 297   // even if the current match is for the same URL as the last run's
 298   // default match.  Likewise, the controller doesn't know what's
 299   // happened in the edit since the last time it ran autocomplete.
 300   // The user might have selected all the text and hit delete, then
 301   // typed a new character.  The selection and delete won't send any
 302   // signals to the controller so it doesn't realize that anything was
 303   // cleared or changed.  Even if the default match hasn't changed, we
 304   // need the edit model to update the display.
 305   UpdateResult(false, true);
 306
 307   if (!done_) {
 308     StartExpireTimer();
 309     StartStopTimer();
 310   }
 311 }
 312
 313 void AutocompleteController::Stop(bool clear_result) {
 314   for (Providers::const_iterator i(providers_.begin()); i != providers_.end();
 315        ++i) {
 316     (*i)->Stop(clear_result);
 317   }
 318
 319   expire_timer_.Stop();
 320   stop_timer_.Stop();
 321   done_ = true;
 322   if (clear_result && !result_.empty()) {
 323     result_.Reset();
 324     // NOTE: We pass in false since we're trying to only clear the popup, not
 325     // touch the edit... this is all a mess and should be cleaned up :(
 326     NotifyChanged(false);
 327   }
 328 }
 329
 330 void AutocompleteController::OnOmniboxFocused(const AutocompleteInput& input) {
 331   DCHECK(!in_start_);  // We should not be already running a query.
 332
 333   // Call Start() on all prefix-based providers with an INVALID
 334   // AutocompleteInput to clear out cached |matches_|, which ensures that
 335   // they aren't used with zero suggest.
 336   for (Providers::iterator i(providers_.begin()); i != providers_.end(); ++i) {
 337     if ((*i)->ProvidesMatchesOnOmniboxFocus())
 338       (*i)->Start(input, false);
 339     else
 340       (*i)->Start(AutocompleteInput(), false);
 341   }
 342
 343   UpdateResult(false, false);
 344 }
 345
 346 void AutocompleteController::DeleteMatch(const AutocompleteMatch& match) {
 347   DCHECK(match.SupportsDeletion());
 348
 349   // Delete duplicate matches attached to the main match first.
 350   for (ACMatches::const_iterator it(match.duplicate_matches.begin());
 351        it != match.duplicate_matches.end(); ++it) {
 352     if (it->deletable)
 353       it->provider->DeleteMatch(*it);
 354   }
 355
 356   if (match.deletable)
 357     match.provider->DeleteMatch(match);
 358
 359   OnProviderUpdate(true);
 360
 361   // If we're not done, we might attempt to redisplay the deleted match. Make
 362   // sure we aren't displaying it by removing any old entries.
 363   ExpireCopiedEntries();
 364 }
 365
 366 void AutocompleteController::ExpireCopiedEntries() {
 367   // The first true makes UpdateResult() clear out the results and
 368   // regenerate them, thus ensuring that no results from the previous
 369   // result set remain.
 370   UpdateResult(true, false);
 371 }
 372
 373 void AutocompleteController::OnProviderUpdate(bool updated_matches) {
 374   CheckIfDone();
 375   // Multiple providers may provide synchronous results, so we only update the
 376   // results if we're not in Start().
 377   if (!in_start_ && (updated_matches || done_))
 378     UpdateResult(false, false);
 379 }
 380
 381 void AutocompleteController::AddProvidersInfo(
 382     ProvidersInfo* provider_info) const {
 383   provider_info->clear();
 384   for (Providers::const_iterator i(providers_.begin()); i != providers_.end();
 385        ++i) {
 386     // Add per-provider info, if any.
 387     (*i)->AddProviderInfo(provider_info);
 388
 389     // This is also a good place to put code to add info that you want to
 390     // add for every provider.
 391   }
 392 }
 393
 394 void AutocompleteController::ResetSession() {
 395   for (Providers::const_iterator i(providers_.begin()); i != providers_.end();
 396        ++i)
 397     (*i)->ResetSession();
 398 }
 399
 400 void AutocompleteController::UpdateMatchDestinationURLWithQueryFormulationTime(
 401     base::TimeDelta query_formulation_time,
 402     AutocompleteMatch* match) const {
 403   if (!match->search_terms_args.get() ||
 404       match->search_terms_args->assisted_query_stats.empty())
 405     return;
 406
 407   // Append the query formulation time (time from when the user first typed a
 408   // character into the omnibox to when the user selected a query) and whether
 409   // a field trial has triggered to the AQS parameter.
 410   TemplateURLRef::SearchTermsArgs search_terms_args(*match->search_terms_args);
 411   search_terms_args.assisted_query_stats += base::StringPrintf(
 412       ".%" PRId64 "j%dj%d",
 413       query_formulation_time.InMilliseconds(),
 414       (search_provider_ &&
 415        search_provider_->field_trial_triggered_in_session()) ||
 416       (zero_suggest_provider_ &&
 417        zero_suggest_provider_->field_trial_triggered_in_session()),
 418       input_.current_page_classification());
 419   UpdateMatchDestinationURL(search_terms_args, match);
 420 }
 421
 422 void AutocompleteController::UpdateMatchDestinationURL(
 423     const TemplateURLRef::SearchTermsArgs& search_terms_args,
 424     AutocompleteMatch* match) const {
 425   TemplateURL* template_url = match->GetTemplateURL(
 426       template_url_service_, false);
 427   if (!template_url)
 428     return;
 429
 430   match->destination_url = GURL(template_url->url_ref().ReplaceSearchTerms(
 431       search_terms_args, template_url_service_->search_terms_data()));
 432 }
 433
 434 void AutocompleteController::UpdateResult(
 435     bool regenerate_result,
 436     bool force_notify_default_match_changed) {
 437   const bool last_default_was_valid = result_.default_match() != result_.end();
 438   // The following three variables are only set and used if
 439   // |last_default_was_valid|.
 440   base::string16 last_default_fill_into_edit, last_default_keyword,
 441       last_default_associated_keyword;
 442   if (last_default_was_valid) {
 443     last_default_fill_into_edit = result_.default_match()->fill_into_edit;
 444     last_default_keyword = result_.default_match()->keyword;
 445     if (result_.default_match()->associated_keyword != NULL)
 446       last_default_associated_keyword =
 447           result_.default_match()->associated_keyword->keyword;
 448   }
 449
 450   if (regenerate_result)
 451     result_.Reset();
 452
 453   AutocompleteResult last_result;
 454   last_result.Swap(&result_);
 455
 456   for (Providers::const_iterator i(providers_.begin());
 457        i != providers_.end(); ++i)
 458     result_.AppendMatches((*i)->matches());
 459
 460   // Sort the matches and trim to a small number of "best" matches.
 461   result_.SortAndCull(input_, template_url_service_);
 462
 463   // Need to validate before invoking CopyOldMatches as the old matches are not
 464   // valid against the current input.
 465 #ifndef NDEBUG
 466   result_.Validate();
 467 #endif
 468
 469   if (!done_) {
 470     // This conditional needs to match the conditional in Start that invokes
 471     // StartExpireTimer.
 472     result_.CopyOldMatches(input_, last_result, template_url_service_);
 473   }
 474
 475   UpdateKeywordDescriptions(&result_);
 476   UpdateAssociatedKeywords(&result_);
 477   UpdateAssistedQueryStats(&result_);
 478   if (search_provider_)
 479     search_provider_->RegisterDisplayedAnswers(result_);
 480
 481   const bool default_is_valid = result_.default_match() != result_.end();
 482   base::string16 default_associated_keyword;
 483   if (default_is_valid &&
 484       (result_.default_match()->associated_keyword != NULL)) {
 485     default_associated_keyword =
 486         result_.default_match()->associated_keyword->keyword;
 487   }
 488   // We've gotten async results. Send notification that the default match
 489   // updated if fill_into_edit, associated_keyword, or keyword differ.  (The
 490   // second can change if we've just started Chrome and the keyword database
 491   // finishes loading while processing this request.  The third can change
 492   // if we swapped from interpreting the input as a search--which gets
 493   // labeled with the default search provider's keyword--to a URL.)
 494   // We don't check the URL as that may change for the default match
 495   // even though the fill into edit hasn't changed (see SearchProvider
 496   // for one case of this).
 497   const bool notify_default_match =
 498       (last_default_was_valid != default_is_valid) ||
 499       (last_default_was_valid &&
 500        ((result_.default_match()->fill_into_edit !=
 501           last_default_fill_into_edit) ||
 502         (default_associated_keyword != last_default_associated_keyword) ||
 503         (result_.default_match()->keyword != last_default_keyword)));
 504   if (notify_default_match)
 505     last_time_default_match_changed_ = base::TimeTicks::Now();
 506
 507   NotifyChanged(force_notify_default_match_changed || notify_default_match);
 508 }
 509
 510 void AutocompleteController::UpdateAssociatedKeywords(
 511     AutocompleteResult* result) {
 512   if (!keyword_provider_)
 513     return;
 514
 515   // Determine if the user's input is an exact keyword match.
 516   base::string16 exact_keyword = keyword_provider_->GetKeywordForText(
 517       TemplateURLService::CleanUserInputKeyword(input_.text()));
 518
 519   std::set<base::string16> keywords;
 520   for (ACMatches::iterator match(result->begin()); match != result->end();
 521        ++match) {
 522     base::string16 keyword(
 523         match->GetSubstitutingExplicitlyInvokedKeyword(template_url_service_));
 524     if (!keyword.empty()) {
 525       keywords.insert(keyword);
 526       continue;
 527     }
 528
 529     // When the user has typed an exact keyword, we want tab-to-search on the
 530     // default match to select that keyword, even if the match
 531     // inline-autocompletes to a different keyword.  (This prevents inline
 532     // autocompletions from blocking a user's attempts to use an explicitly-set
 533     // keyword of their own creation.)  So use |exact_keyword| if it's
 534     // available.
 535     if (!exact_keyword.empty() && !keywords.count(exact_keyword)) {
 536       keywords.insert(exact_keyword);
 537       match->associated_keyword.reset(new AutocompleteMatch(
 538           keyword_provider_->CreateVerbatimMatch(exact_keyword,
 539                                                  exact_keyword, input_)));
 540       continue;
 541     }
 542
 543     // Otherwise, set a match's associated keyword based on the match's
 544     // fill_into_edit, which should take inline autocompletions into account.
 545     keyword = keyword_provider_->GetKeywordForText(match->fill_into_edit);
 546
 547     // Only add the keyword if the match does not have a duplicate keyword with
 548     // a more relevant match.
 549     if (!keyword.empty() && !keywords.count(keyword)) {
 550       keywords.insert(keyword);
 551       match->associated_keyword.reset(new AutocompleteMatch(
 552           keyword_provider_->CreateVerbatimMatch(match->fill_into_edit,
 553                                                  keyword, input_)));
 554     } else {
 555       match->associated_keyword.reset();
 556     }
 557   }
 558 }
 559
 560 void AutocompleteController::UpdateKeywordDescriptions(
 561     AutocompleteResult* result) {
 562   base::string16 last_keyword;
 563   for (AutocompleteResult::iterator i(result->begin()); i != result->end();
 564        ++i) {
 565     if (AutocompleteMatch::IsSearchType(i->type)) {
 566       if (AutocompleteMatchHasCustomDescription(*i))
 567         continue;
 568       i->description.clear();
 569       i->description_class.clear();
 570       DCHECK(!i->keyword.empty());
 571       if (i->keyword != last_keyword) {
 572         const TemplateURL* template_url =
 573             i->GetTemplateURL(template_url_service_, false);
 574         if (template_url) {
 575           // For extension keywords, just make the description the extension
 576           // name -- don't assume that the normal search keyword description is
 577           // applicable.
 578           i->description = template_url->AdjustedShortNameForLocaleDirection();
 579           if (template_url->GetType() != TemplateURL::OMNIBOX_API_EXTENSION) {
 580             i->description = l10n_util::GetStringFUTF16(
 581                 IDS_AUTOCOMPLETE_SEARCH_DESCRIPTION, i->description);
 582           }
 583           i->description_class.push_back(
 584               ACMatchClassification(0, ACMatchClassification::DIM));
 585         }
 586         last_keyword = i->keyword;
 587       }
 588     } else {
 589       last_keyword.clear();
 590     }
 591   }
 592 }
 593
 594 void AutocompleteController::UpdateAssistedQueryStats(
 595     AutocompleteResult* result) {
 596   if (result->empty())
 597     return;
 598
 599   // Build the impressions string (the AQS part after ".").
 600   std::string autocompletions;
 601   int count = 0;
 602   size_t last_type = base::string16::npos;
 603   size_t last_subtype = base::string16::npos;
 604   for (ACMatches::iterator match(result->begin()); match != result->end();
 605        ++match) {
 606     size_t type = base::string16::npos;
 607     size_t subtype = base::string16::npos;
 608     AutocompleteMatchToAssistedQuery(
 609         match->type, match->provider, &type, &subtype);
 610     if (last_type != base::string16::npos &&
 611         (type != last_type || subtype != last_subtype)) {
 612       AppendAvailableAutocompletion(
 613           last_type, last_subtype, count, &autocompletions);
 614       count = 1;
 615     } else {
 616       count++;
 617     }
 618     last_type = type;
 619     last_subtype = subtype;
 620   }
 621   AppendAvailableAutocompletion(
 622       last_type, last_subtype, count, &autocompletions);
 623   // Go over all matches and set AQS if the match supports it.
 624   for (size_t index = 0; index < result->size(); ++index) {
 625     AutocompleteMatch* match = result->match_at(index);
 626     const TemplateURL* template_url =
 627         match->GetTemplateURL(template_url_service_, false);
 628     if (!template_url || !match->search_terms_args.get())
 629       continue;
 630     std::string selected_index;
 631     // Prevent trivial suggestions from getting credit for being selected.
 632     if (!IsTrivialAutocompletion(*match))
 633       selected_index = base::StringPrintf("%" PRIuS, index);
 634     match->search_terms_args->assisted_query_stats =
 635         base::StringPrintf("chrome.%s.%s",
 636                            selected_index.c_str(),
 637                            autocompletions.c_str());
 638     match->destination_url = GURL(template_url->url_ref().ReplaceSearchTerms(
 639         *match->search_terms_args, template_url_service_->search_terms_data()));
 640   }
 641 }
 642
 643 void AutocompleteController::NotifyChanged(bool notify_default_match) {
 644   if (delegate_)
 645     delegate_->OnResultChanged(notify_default_match);
 646   if (done_) {
 647     content::NotificationService::current()->Notify(
 648         chrome::NOTIFICATION_AUTOCOMPLETE_CONTROLLER_RESULT_READY,
 649         content::Source<AutocompleteController>(this),
 650         content::NotificationService::NoDetails());
 651   }
 652 }
 653
 654 void AutocompleteController::CheckIfDone() {
 655   for (Providers::const_iterator i(providers_.begin()); i != providers_.end();
 656        ++i) {
 657     if (!(*i)->done()) {
 658       done_ = false;
 659       return;
 660     }
 661   }
 662   done_ = true;
 663 }
 664
 665 void AutocompleteController::StartExpireTimer() {
 666   // Amount of time (in ms) between when the user stops typing and
 667   // when we remove any copied entries. We do this from the time the
 668   // user stopped typing as some providers (such as SearchProvider)
 669   // wait for the user to stop typing before they initiate a query.
 670   const int kExpireTimeMS = 500;
 671
 672   if (result_.HasCopiedMatches())
 673     expire_timer_.Start(FROM_HERE,
 674                         base::TimeDelta::FromMilliseconds(kExpireTimeMS),
 675                         this, &AutocompleteController::ExpireCopiedEntries);
 676 }
 677
 678 void AutocompleteController::StartStopTimer() {
 679   stop_timer_.Start(FROM_HERE,
 680                     stop_timer_duration_,
 681                     base::Bind(&AutocompleteController::Stop,
 682                                base::Unretained(this),
 683                                false));
 684 }