src/chrome/browser/ui/webui/downloads_dom_handler.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/ui/webui/downloads_dom_handler.h"
   6
   7 #include <algorithm>
   8 #include <functional>
   9
  10 #include "base/basictypes.h"
  11 #include "base/bind.h"
  12 #include "base/bind_helpers.h"
  13 #include "base/i18n/rtl.h"
  14 #include "base/i18n/time_formatting.h"
  15 #include "base/memory/singleton.h"
  16 #include "base/metrics/field_trial.h"
  17 #include "base/metrics/histogram.h"
  18 #include "base/prefs/pref_service.h"
  19 #include "base/strings/string_piece.h"
  20 #include "base/strings/utf_string_conversions.h"
  21 #include "base/threading/thread.h"
  22 #include "base/value_conversions.h"
  23 #include "base/values.h"
  24 #include "chrome/browser/browser_process.h"
  25 #include "chrome/browser/download/download_crx_util.h"
  26 #include "chrome/browser/download/download_danger_prompt.h"
  27 #include "chrome/browser/download/download_history.h"
  28 #include "chrome/browser/download/download_item_model.h"
  29 #include "chrome/browser/download/download_prefs.h"
  30 #include "chrome/browser/download/download_query.h"
  31 #include "chrome/browser/download/download_service.h"
  32 #include "chrome/browser/download/download_service_factory.h"
  33 #include "chrome/browser/download/drag_download_item.h"
  34 #include "chrome/browser/extensions/api/downloads/downloads_api.h"
  35 #include "chrome/browser/extensions/extension_service.h"
  36 #include "chrome/browser/platform_util.h"
  37 #include "chrome/browser/profiles/profile.h"
  38 #include "chrome/browser/ui/webui/fileicon_source.h"
  39 #include "chrome/common/pref_names.h"
  40 #include "chrome/common/url_constants.h"
  41 #include "content/public/browser/browser_thread.h"
  42 #include "content/public/browser/download_item.h"
  43 #include "content/public/browser/url_data_source.h"
  44 #include "content/public/browser/user_metrics.h"
  45 #include "content/public/browser/web_contents.h"
  46 #include "content/public/browser/web_ui.h"
  47 #include "extensions/browser/extension_system.h"
  48 #include "grit/generated_resources.h"
  49 #include "net/base/filename_util.h"
  50 #include "ui/base/l10n/time_format.h"
  51 #include "ui/gfx/image/image.h"
  52
  53 using base::UserMetricsAction;
  54 using content::BrowserContext;
  55 using content::BrowserThread;
  56
  57 namespace {
  58
  59 // Maximum number of downloads to show. TODO(glen): Remove this and instead
  60 // stuff the downloads down the pipe slowly.
  61 static const size_t kMaxDownloads = 150;
  62
  63 enum DownloadsDOMEvent {
  64   DOWNLOADS_DOM_EVENT_GET_DOWNLOADS = 0,
  65   DOWNLOADS_DOM_EVENT_OPEN_FILE = 1,
  66   DOWNLOADS_DOM_EVENT_DRAG = 2,
  67   DOWNLOADS_DOM_EVENT_SAVE_DANGEROUS = 3,
  68   DOWNLOADS_DOM_EVENT_DISCARD_DANGEROUS = 4,
  69   DOWNLOADS_DOM_EVENT_SHOW = 5,
  70   DOWNLOADS_DOM_EVENT_PAUSE = 6,
  71   DOWNLOADS_DOM_EVENT_REMOVE = 7,
  72   DOWNLOADS_DOM_EVENT_CANCEL = 8,
  73   DOWNLOADS_DOM_EVENT_CLEAR_ALL = 9,
  74   DOWNLOADS_DOM_EVENT_OPEN_FOLDER = 10,
  75   DOWNLOADS_DOM_EVENT_RESUME = 11,
  76   DOWNLOADS_DOM_EVENT_MAX
  77 };
  78
  79 void CountDownloadsDOMEvents(DownloadsDOMEvent event) {
  80   UMA_HISTOGRAM_ENUMERATION("Download.DOMEvent",
  81                             event,
  82                             DOWNLOADS_DOM_EVENT_MAX);
  83 }
  84
  85 // Returns a string constant to be used as the |danger_type| value in
  86 // CreateDownloadItemValue().  Only return strings for DANGEROUS_FILE,
  87 // DANGEROUS_URL, DANGEROUS_CONTENT, and UNCOMMON_CONTENT because the
  88 // |danger_type| value is only defined if the value of |state| is |DANGEROUS|.
  89 const char* GetDangerTypeString(content::DownloadDangerType danger_type) {
  90   switch (danger_type) {
  91     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_FILE:
  92       return "DANGEROUS_FILE";
  93     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_URL:
  94       return "DANGEROUS_URL";
  95     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_CONTENT:
  96       return "DANGEROUS_CONTENT";
  97     case content::DOWNLOAD_DANGER_TYPE_UNCOMMON_CONTENT:
  98       return "UNCOMMON_CONTENT";
  99     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_HOST:
 100       return "DANGEROUS_HOST";
 101     case content::DOWNLOAD_DANGER_TYPE_POTENTIALLY_UNWANTED:
 102       return "POTENTIALLY_UNWANTED";
 103     default:
 104       // Don't return a danger type string if it is NOT_DANGEROUS or
 105       // MAYBE_DANGEROUS_CONTENT.
 106       NOTREACHED();
 107       return "";
 108   }
 109 }
 110
 111 // Returns a JSON dictionary containing some of the attributes of |download|.
 112 // The JSON dictionary will also have a field "id" set to |id|, and a field
 113 // "otr" set to |incognito|.
 114 base::DictionaryValue* CreateDownloadItemValue(
 115     content::DownloadItem* download_item,
 116     bool incognito) {
 117   // TODO(asanka): Move towards using download_model here for getting status and
 118   // progress. The difference currently only matters to Drive downloads and
 119   // those don't show up on the downloads page, but should.
 120   DownloadItemModel download_model(download_item);
 121   base::DictionaryValue* file_value = new base::DictionaryValue();
 122
 123   file_value->SetInteger(
 124       "started", static_cast<int>(download_item->GetStartTime().ToTimeT()));
 125   file_value->SetString(
 126       "since_string", ui::TimeFormat::RelativeDate(
 127           download_item->GetStartTime(), NULL));
 128   file_value->SetString(
 129       "date_string", base::TimeFormatShortDate(download_item->GetStartTime()));
 130   file_value->SetInteger("id", download_item->GetId());
 131
 132   base::FilePath download_path(download_item->GetTargetFilePath());
 133   file_value->Set("file_path", base::CreateFilePathValue(download_path));
 134   file_value->SetString("file_url",
 135                         net::FilePathToFileURL(download_path).spec());
 136
 137   extensions::DownloadedByExtension* by_ext =
 138       extensions::DownloadedByExtension::Get(download_item);
 139   if (by_ext) {
 140     file_value->SetString("by_ext_id", by_ext->id());
 141     file_value->SetString("by_ext_name", by_ext->name());
 142     // Lookup the extension's current name() in case the user changed their
 143     // language. This won't work if the extension was uninstalled, so the name
 144     // might be the wrong language.
 145     bool include_disabled = true;
 146     const extensions::Extension* extension = extensions::ExtensionSystem::Get(
 147         Profile::FromBrowserContext(download_item->GetBrowserContext()))->
 148       extension_service()->GetExtensionById(by_ext->id(), include_disabled);
 149     if (extension)
 150       file_value->SetString("by_ext_name", extension->name());
 151   }
 152
 153   // Keep file names as LTR.
 154   base::string16 file_name =
 155     download_item->GetFileNameToReportUser().LossyDisplayName();
 156   file_name = base::i18n::GetDisplayStringInLTRDirectionality(file_name);
 157   file_value->SetString("file_name", file_name);
 158   file_value->SetString("url", download_item->GetURL().spec());
 159   file_value->SetBoolean("otr", incognito);
 160   file_value->SetInteger("total", static_cast<int>(
 161       download_item->GetTotalBytes()));
 162   file_value->SetBoolean("file_externally_removed",
 163                          download_item->GetFileExternallyRemoved());
 164   file_value->SetBoolean("retry", false); // Overridden below if needed.
 165   file_value->SetBoolean("resume", download_item->CanResume());
 166
 167   switch (download_item->GetState()) {
 168     case content::DownloadItem::IN_PROGRESS:
 169       if (download_item->IsDangerous()) {
 170         file_value->SetString("state", "DANGEROUS");
 171         // These are the only danger states that the UI is equipped to handle.
 172         DCHECK(download_item->GetDangerType() ==
 173                    content::DOWNLOAD_DANGER_TYPE_DANGEROUS_FILE ||
 174                download_item->GetDangerType() ==
 175                    content::DOWNLOAD_DANGER_TYPE_DANGEROUS_URL ||
 176                download_item->GetDangerType() ==
 177                    content::DOWNLOAD_DANGER_TYPE_DANGEROUS_CONTENT ||
 178                download_item->GetDangerType() ==
 179                    content::DOWNLOAD_DANGER_TYPE_UNCOMMON_CONTENT ||
 180                download_item->GetDangerType() ==
 181                    content::DOWNLOAD_DANGER_TYPE_DANGEROUS_HOST ||
 182                download_item->GetDangerType() ==
 183                    content::DOWNLOAD_DANGER_TYPE_POTENTIALLY_UNWANTED);
 184         const char* danger_type_value =
 185             GetDangerTypeString(download_item->GetDangerType());
 186         file_value->SetString("danger_type", danger_type_value);
 187       } else if (download_item->IsPaused()) {
 188         file_value->SetString("state", "PAUSED");
 189       } else {
 190         file_value->SetString("state", "IN_PROGRESS");
 191       }
 192       file_value->SetString("progress_status_text",
 193                             download_model.GetTabProgressStatusText());
 194
 195       file_value->SetInteger("percent",
 196           static_cast<int>(download_item->PercentComplete()));
 197       file_value->SetInteger("received",
 198           static_cast<int>(download_item->GetReceivedBytes()));
 199       break;
 200
 201     case content::DownloadItem::INTERRUPTED:
 202       file_value->SetString("state", "INTERRUPTED");
 203
 204       file_value->SetString("progress_status_text",
 205                             download_model.GetTabProgressStatusText());
 206
 207       file_value->SetInteger("percent",
 208           static_cast<int>(download_item->PercentComplete()));
 209       file_value->SetInteger("received",
 210           static_cast<int>(download_item->GetReceivedBytes()));
 211       file_value->SetString("last_reason_text",
 212                             download_model.GetInterruptReasonText());
 213       if (content::DOWNLOAD_INTERRUPT_REASON_CRASH ==
 214           download_item->GetLastReason() && !download_item->CanResume())
 215         file_value->SetBoolean("retry", true);
 216       break;
 217
 218     case content::DownloadItem::CANCELLED:
 219       file_value->SetString("state", "CANCELLED");
 220       file_value->SetBoolean("retry", true);
 221       break;
 222
 223     case content::DownloadItem::COMPLETE:
 224       DCHECK(!download_item->IsDangerous());
 225       file_value->SetString("state", "COMPLETE");
 226       break;
 227
 228     case content::DownloadItem::MAX_DOWNLOAD_STATE:
 229       NOTREACHED() << "state undefined";
 230   }
 231
 232   return file_value;
 233 }
 234
 235 // Filters out extension downloads and downloads that don't have a filename yet.
 236 bool IsDownloadDisplayable(const content::DownloadItem& item) {
 237   return (!download_crx_util::IsExtensionDownload(item) &&
 238           !item.IsTemporary() &&
 239           !item.GetFileNameToReportUser().empty() &&
 240           !item.GetTargetFilePath().empty());
 241 }
 242
 243 }  // namespace
 244
 245 DownloadsDOMHandler::DownloadsDOMHandler(content::DownloadManager* dlm)
 246     : main_notifier_(dlm, this),
 247       update_scheduled_(false),
 248       weak_ptr_factory_(this) {
 249   // Create our fileicon data source.
 250   Profile* profile = Profile::FromBrowserContext(dlm->GetBrowserContext());
 251   content::URLDataSource::Add(profile, new FileIconSource());
 252
 253   if (profile->IsOffTheRecord()) {
 254     original_notifier_.reset(new AllDownloadItemNotifier(
 255         BrowserContext::GetDownloadManager(profile->GetOriginalProfile()),
 256         this));
 257   }
 258 }
 259
 260 DownloadsDOMHandler::~DownloadsDOMHandler() {
 261 }
 262
 263 // DownloadsDOMHandler, public: -----------------------------------------------
 264
 265 void DownloadsDOMHandler::OnPageLoaded(const base::ListValue* args) {
 266   SendCurrentDownloads();
 267 }
 268
 269 void DownloadsDOMHandler::RegisterMessages() {
 270   web_ui()->RegisterMessageCallback("onPageLoaded",
 271       base::Bind(&DownloadsDOMHandler::OnPageLoaded,
 272                  weak_ptr_factory_.GetWeakPtr()));
 273   web_ui()->RegisterMessageCallback("getDownloads",
 274       base::Bind(&DownloadsDOMHandler::HandleGetDownloads,
 275                  weak_ptr_factory_.GetWeakPtr()));
 276   web_ui()->RegisterMessageCallback("openFile",
 277       base::Bind(&DownloadsDOMHandler::HandleOpenFile,
 278                  weak_ptr_factory_.GetWeakPtr()));
 279   web_ui()->RegisterMessageCallback("drag",
 280       base::Bind(&DownloadsDOMHandler::HandleDrag,
 281                  weak_ptr_factory_.GetWeakPtr()));
 282   web_ui()->RegisterMessageCallback("saveDangerous",
 283       base::Bind(&DownloadsDOMHandler::HandleSaveDangerous,
 284                  weak_ptr_factory_.GetWeakPtr()));
 285   web_ui()->RegisterMessageCallback("discardDangerous",
 286       base::Bind(&DownloadsDOMHandler::HandleDiscardDangerous,
 287                  weak_ptr_factory_.GetWeakPtr()));
 288   web_ui()->RegisterMessageCallback("show",
 289       base::Bind(&DownloadsDOMHandler::HandleShow,
 290                  weak_ptr_factory_.GetWeakPtr()));
 291   web_ui()->RegisterMessageCallback("pause",
 292       base::Bind(&DownloadsDOMHandler::HandlePause,
 293                  weak_ptr_factory_.GetWeakPtr()));
 294   web_ui()->RegisterMessageCallback("resume",
 295       base::Bind(&DownloadsDOMHandler::HandleResume,
 296                  weak_ptr_factory_.GetWeakPtr()));
 297   web_ui()->RegisterMessageCallback("remove",
 298       base::Bind(&DownloadsDOMHandler::HandleRemove,
 299                  weak_ptr_factory_.GetWeakPtr()));
 300   web_ui()->RegisterMessageCallback("cancel",
 301       base::Bind(&DownloadsDOMHandler::HandleCancel,
 302                  weak_ptr_factory_.GetWeakPtr()));
 303   web_ui()->RegisterMessageCallback("clearAll",
 304       base::Bind(&DownloadsDOMHandler::HandleClearAll,
 305                  weak_ptr_factory_.GetWeakPtr()));
 306   web_ui()->RegisterMessageCallback("openDownloadsFolder",
 307       base::Bind(&DownloadsDOMHandler::HandleOpenDownloadsFolder,
 308                  weak_ptr_factory_.GetWeakPtr()));
 309 }
 310
 311 void DownloadsDOMHandler::OnDownloadCreated(
 312     content::DownloadManager* manager, content::DownloadItem* download_item) {
 313   if (IsDownloadDisplayable(*download_item))
 314     ScheduleSendCurrentDownloads();
 315 }
 316
 317 void DownloadsDOMHandler::OnDownloadUpdated(
 318     content::DownloadManager* manager,
 319     content::DownloadItem* download_item) {
 320   if (IsDownloadDisplayable(*download_item)) {
 321     if (search_terms_ && !search_terms_->empty()) {
 322       // Don't CallDownloadUpdated() if download_item doesn't match
 323       // search_terms_.
 324       // TODO(benjhayden): Consider splitting MatchesQuery() out to a function.
 325       content::DownloadManager::DownloadVector all_items, filtered_items;
 326       all_items.push_back(download_item);
 327       DownloadQuery query;
 328       query.AddFilter(DownloadQuery::FILTER_QUERY, *search_terms_.get());
 329       query.Search(all_items.begin(), all_items.end(), &filtered_items);
 330       if (filtered_items.empty())
 331         return;
 332     }
 333     base::ListValue results_value;
 334     results_value.Append(CreateDownloadItemValue(
 335         download_item,
 336         (original_notifier_.get() &&
 337           (manager == main_notifier_.GetManager()))));
 338     CallDownloadUpdated(results_value);
 339   }
 340 }
 341
 342 void DownloadsDOMHandler::OnDownloadRemoved(
 343     content::DownloadManager* manager,
 344     content::DownloadItem* download_item) {
 345   // This relies on |download_item| being removed from DownloadManager in this
 346   // MessageLoop iteration. |download_item| may not have been removed from
 347   // DownloadManager when OnDownloadRemoved() is fired, so bounce off the
 348   // MessageLoop to give it a chance to be removed. SendCurrentDownloads() looks
 349   // at all downloads, and we do not tell it that |download_item| is being
 350   // removed. If DownloadManager is ever changed to not immediately remove
 351   // |download_item| from its map when OnDownloadRemoved is sent, then
 352   // DownloadsDOMHandler::OnDownloadRemoved() will need to explicitly tell
 353   // SendCurrentDownloads() that |download_item| was removed. A
 354   // SupportsUserData::Data would be the correct way to do this.
 355   ScheduleSendCurrentDownloads();
 356 }
 357
 358 void DownloadsDOMHandler::HandleGetDownloads(const base::ListValue* args) {
 359   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_GET_DOWNLOADS);
 360   search_terms_.reset((args && !args->empty()) ? args->DeepCopy() : NULL);
 361   SendCurrentDownloads();
 362 }
 363
 364 void DownloadsDOMHandler::HandleOpenFile(const base::ListValue* args) {
 365   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_OPEN_FILE);
 366   content::DownloadItem* file = GetDownloadByValue(args);
 367   if (file)
 368     file->OpenDownload();
 369 }
 370
 371 void DownloadsDOMHandler::HandleDrag(const base::ListValue* args) {
 372   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_DRAG);
 373   content::DownloadItem* file = GetDownloadByValue(args);
 374   if (!file)
 375     return;
 376
 377   content::WebContents* web_contents = GetWebUIWebContents();
 378   // |web_contents| is only NULL in the test.
 379   if (!web_contents)
 380     return;
 381
 382   if (file->GetState() != content::DownloadItem::COMPLETE)
 383     return;
 384
 385   gfx::Image* icon = g_browser_process->icon_manager()->LookupIconFromFilepath(
 386       file->GetTargetFilePath(), IconLoader::NORMAL);
 387   gfx::NativeView view = web_contents->GetNativeView();
 388   {
 389     // Enable nested tasks during DnD, while |DragDownload()| blocks.
 390     base::MessageLoop::ScopedNestableTaskAllower allow(
 391         base::MessageLoop::current());
 392     DragDownloadItem(file, icon, view);
 393   }
 394 }
 395
 396 void DownloadsDOMHandler::HandleSaveDangerous(const base::ListValue* args) {
 397   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_SAVE_DANGEROUS);
 398   content::DownloadItem* file = GetDownloadByValue(args);
 399   if (file)
 400     ShowDangerPrompt(file);
 401 }
 402
 403 void DownloadsDOMHandler::HandleDiscardDangerous(const base::ListValue* args) {
 404   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_DISCARD_DANGEROUS);
 405   content::DownloadItem* file = GetDownloadByValue(args);
 406   if (file)
 407     file->Remove();
 408 }
 409
 410 void DownloadsDOMHandler::HandleShow(const base::ListValue* args) {
 411   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_SHOW);
 412   content::DownloadItem* file = GetDownloadByValue(args);
 413   if (file)
 414     file->ShowDownloadInShell();
 415 }
 416
 417 void DownloadsDOMHandler::HandlePause(const base::ListValue* args) {
 418   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_PAUSE);
 419   content::DownloadItem* file = GetDownloadByValue(args);
 420   if (file)
 421     file->Pause();
 422 }
 423
 424 void DownloadsDOMHandler::HandleResume(const base::ListValue* args) {
 425   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_RESUME);
 426   content::DownloadItem* file = GetDownloadByValue(args);
 427   if (file)
 428     file->Resume();
 429 }
 430
 431 void DownloadsDOMHandler::HandleRemove(const base::ListValue* args) {
 432   if (!IsDeletingHistoryAllowed())
 433     return;
 434
 435   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_REMOVE);
 436   content::DownloadItem* file = GetDownloadByValue(args);
 437   if (file)
 438     file->Remove();
 439 }
 440
 441 void DownloadsDOMHandler::HandleCancel(const base::ListValue* args) {
 442   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_CANCEL);
 443   content::DownloadItem* file = GetDownloadByValue(args);
 444   if (file)
 445     file->Cancel(true);
 446 }
 447
 448 void DownloadsDOMHandler::HandleClearAll(const base::ListValue* args) {
 449   if (IsDeletingHistoryAllowed()) {
 450     CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_CLEAR_ALL);
 451     // IsDeletingHistoryAllowed already checked for the existence of the
 452     // manager.
 453     main_notifier_.GetManager()->RemoveAllDownloads();
 454
 455     // If this is an incognito downloads page, clear All should clear main
 456     // download manager as well.
 457     if (original_notifier_.get() && original_notifier_->GetManager())
 458       original_notifier_->GetManager()->RemoveAllDownloads();
 459   }
 460
 461   // downloads.js always clears the display and relies on HandleClearAll to
 462   // ScheduleSendCurrentDownloads(). If any downloads are removed, then
 463   // OnDownloadRemoved() will call it, but if no downloads are actually removed,
 464   // then HandleClearAll needs to call it manually.
 465   ScheduleSendCurrentDownloads();
 466 }
 467
 468 void DownloadsDOMHandler::HandleOpenDownloadsFolder(
 469     const base::ListValue* args) {
 470   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_OPEN_FOLDER);
 471   content::DownloadManager* manager = main_notifier_.GetManager();
 472   if (manager) {
 473     platform_util::OpenItem(
 474         Profile::FromBrowserContext(manager->GetBrowserContext()),
 475         DownloadPrefs::FromDownloadManager(manager)->DownloadPath());
 476   }
 477 }
 478
 479 // DownloadsDOMHandler, private: ----------------------------------------------
 480
 481 void DownloadsDOMHandler::ScheduleSendCurrentDownloads() {
 482   // Don't call SendCurrentDownloads() every time anything changes. Batch them
 483   // together instead. This may handle hundreds of OnDownloadDestroyed() calls
 484   // in a single UI message loop iteration when the user Clears All downloads.
 485   if (update_scheduled_)
 486     return;
 487   update_scheduled_ = true;
 488   BrowserThread::PostTask(
 489       BrowserThread::UI, FROM_HERE,
 490       base::Bind(&DownloadsDOMHandler::SendCurrentDownloads,
 491                  weak_ptr_factory_.GetWeakPtr()));
 492 }
 493
 494 void DownloadsDOMHandler::SendCurrentDownloads() {
 495   update_scheduled_ = false;
 496   content::DownloadManager::DownloadVector all_items, filtered_items;
 497   if (main_notifier_.GetManager()) {
 498     main_notifier_.GetManager()->GetAllDownloads(&all_items);
 499     main_notifier_.GetManager()->CheckForHistoryFilesRemoval();
 500   }
 501   if (original_notifier_.get() && original_notifier_->GetManager()) {
 502     original_notifier_->GetManager()->GetAllDownloads(&all_items);
 503     original_notifier_->GetManager()->CheckForHistoryFilesRemoval();
 504   }
 505   DownloadQuery query;
 506   if (search_terms_ && !search_terms_->empty()) {
 507     query.AddFilter(DownloadQuery::FILTER_QUERY, *search_terms_.get());
 508   }
 509   query.AddFilter(base::Bind(&IsDownloadDisplayable));
 510   query.AddSorter(DownloadQuery::SORT_START_TIME, DownloadQuery::DESCENDING);
 511   query.Limit(kMaxDownloads);
 512   query.Search(all_items.begin(), all_items.end(), &filtered_items);
 513   base::ListValue results_value;
 514   for (content::DownloadManager::DownloadVector::const_iterator
 515        iter = filtered_items.begin(); iter != filtered_items.end(); ++iter) {
 516     results_value.Append(CreateDownloadItemValue(
 517         *iter,
 518         (original_notifier_.get() &&
 519           main_notifier_.GetManager() &&
 520           (main_notifier_.GetManager()->GetDownload((*iter)->GetId()) ==
 521           *iter))));
 522   }
 523   CallDownloadsList(results_value);
 524 }
 525
 526 void DownloadsDOMHandler::ShowDangerPrompt(
 527     content::DownloadItem* dangerous_item) {
 528   DownloadDangerPrompt* danger_prompt = DownloadDangerPrompt::Create(
 529       dangerous_item,
 530       GetWebUIWebContents(),
 531       false,
 532       base::Bind(&DownloadsDOMHandler::DangerPromptDone,
 533                  weak_ptr_factory_.GetWeakPtr(), dangerous_item->GetId()));
 534   // danger_prompt will delete itself.
 535   DCHECK(danger_prompt);
 536 }
 537
 538 void DownloadsDOMHandler::DangerPromptDone(
 539     int download_id, DownloadDangerPrompt::Action action) {
 540   if (action != DownloadDangerPrompt::ACCEPT)
 541     return;
 542   content::DownloadItem* item = NULL;
 543   if (main_notifier_.GetManager())
 544     item = main_notifier_.GetManager()->GetDownload(download_id);
 545   if (!item && original_notifier_.get() && original_notifier_->GetManager())
 546     item = original_notifier_->GetManager()->GetDownload(download_id);
 547   if (!item || item->IsDone())
 548     return;
 549   CountDownloadsDOMEvents(DOWNLOADS_DOM_EVENT_SAVE_DANGEROUS);
 550   item->ValidateDangerousDownload();
 551 }
 552
 553 bool DownloadsDOMHandler::IsDeletingHistoryAllowed() {
 554   content::DownloadManager* manager = main_notifier_.GetManager();
 555   return (manager &&
 556           Profile::FromBrowserContext(manager->GetBrowserContext())->
 557               GetPrefs()->GetBoolean(prefs::kAllowDeletingBrowserHistory));
 558 }
 559
 560 content::DownloadItem* DownloadsDOMHandler::GetDownloadByValue(
 561     const base::ListValue* args) {
 562   int download_id = -1;
 563   if (!ExtractIntegerValue(args, &download_id))
 564     return NULL;
 565   content::DownloadItem* item = NULL;
 566   if (main_notifier_.GetManager())
 567     item = main_notifier_.GetManager()->GetDownload(download_id);
 568   if (!item && original_notifier_.get() && original_notifier_->GetManager())
 569     item = original_notifier_->GetManager()->GetDownload(download_id);
 570   return item;
 571 }
 572
 573 content::WebContents* DownloadsDOMHandler::GetWebUIWebContents() {
 574   return web_ui()->GetWebContents();
 575 }
 576
 577 void DownloadsDOMHandler::CallDownloadsList(const base::ListValue& downloads) {
 578   web_ui()->CallJavascriptFunction("downloadsList", downloads);
 579 }
 580
 581 void DownloadsDOMHandler::CallDownloadUpdated(
 582     const base::ListValue& download_item) {
 583   web_ui()->CallJavascriptFunction("downloadUpdated", download_item);
 584 }