src/android_webview/renderer/print_web_view_helper.cc

   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 // TODO(sgurun) copied from chrome/renderer. Remove after crbug.com/322276
   6
   7 #include "android_webview/renderer/print_web_view_helper.h"
   8
   9 #include <string>
  10
  11 #include "android_webview/common/print_messages.h"
  12 #include "base/auto_reset.h"
  13 #include "base/command_line.h"
  14 #include "base/json/json_writer.h"
  15 #include "base/logging.h"
  16 #include "base/message_loop/message_loop.h"
  17 #include "base/metrics/histogram.h"
  18 #include "base/process/process_handle.h"
  19 #include "base/strings/string_number_conversions.h"
  20 #include "base/strings/stringprintf.h"
  21 #include "base/strings/utf_string_conversions.h"
  22 #include "content/public/common/web_preferences.h"
  23 #include "content/public/renderer/render_thread.h"
  24 #include "content/public/renderer/render_view.h"
  25 #include "net/base/escape.h"
  26 #include "printing/metafile.h"
  27 #include "printing/metafile_impl.h"
  28 #include "printing/units.h"
  29 #include "skia/ext/vector_platform_device_skia.h"
  30 #include "third_party/WebKit/public/platform/WebSize.h"
  31 #include "third_party/WebKit/public/platform/WebURLRequest.h"
  32 #include "third_party/WebKit/public/web/WebConsoleMessage.h"
  33 #include "third_party/WebKit/public/web/WebDocument.h"
  34 #include "third_party/WebKit/public/web/WebElement.h"
  35 #include "third_party/WebKit/public/web/WebFrameClient.h"
  36 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  37 #include "third_party/WebKit/public/web/WebPlugin.h"
  38 #include "third_party/WebKit/public/web/WebPluginDocument.h"
  39 #include "third_party/WebKit/public/web/WebPrintParams.h"
  40 #include "third_party/WebKit/public/web/WebPrintScalingOption.h"
  41 #include "third_party/WebKit/public/web/WebScriptSource.h"
  42 #include "third_party/WebKit/public/web/WebSettings.h"
  43 #include "third_party/WebKit/public/web/WebView.h"
  44 #include "third_party/WebKit/public/web/WebViewClient.h"
  45 #include "ui/base/l10n/l10n_util.h"
  46 #include "ui/base/resource/resource_bundle.h"
  47
  48 // This code is copied from chrome/renderer/printing. Code is slightly
  49 // modified to run it with webview, and the modifications are marked
  50 // using OS_ANDROID.
  51 // TODO(sgurun): remove the code as part of componentization of printing.
  52
  53 using content::WebPreferences;
  54
  55 namespace printing {
  56
  57 namespace {
  58
  59 enum PrintPreviewHelperEvents {
  60   PREVIEW_EVENT_REQUESTED,
  61   PREVIEW_EVENT_CACHE_HIT,  // Unused
  62   PREVIEW_EVENT_CREATE_DOCUMENT,
  63   PREVIEW_EVENT_NEW_SETTINGS,  // Unused
  64   PREVIEW_EVENT_MAX,
  65 };
  66
  67 const double kMinDpi = 1.0;
  68
  69 #if 0
  70 // TODO(sgurun) android_webview hack
  71 const char kPageLoadScriptFormat[] =
  72     "document.open(); document.write(%s); document.close();";
  73
  74 const char kPageSetupScriptFormat[] = "setup(%s);";
  75
  76 void ExecuteScript(blink::WebFrame* frame,
  77                    const char* script_format,
  78                    const base::Value& parameters) {
  79   std::string json;
  80   base::JSONWriter::Write(&parameters, &json);
  81   std::string script = base::StringPrintf(script_format, json.c_str());
  82   frame->executeScript(blink::WebString(base::UTF8ToUTF16(script)));
  83 }
  84 #endif
  85
  86 int GetDPI(const PrintMsg_Print_Params* print_params) {
  87 #if defined(OS_MACOSX)
  88   // On the Mac, the printable area is in points, don't do any scaling based
  89   // on dpi.
  90   return kPointsPerInch;
  91 #else
  92   return static_cast<int>(print_params->dpi);
  93 #endif  // defined(OS_MACOSX)
  94 }
  95
  96 bool PrintMsg_Print_Params_IsValid(const PrintMsg_Print_Params& params) {
  97   return !params.content_size.IsEmpty() && !params.page_size.IsEmpty() &&
  98          !params.printable_area.IsEmpty() && params.document_cookie &&
  99          params.desired_dpi && params.max_shrink && params.min_shrink &&
 100          params.dpi && (params.margin_top >= 0) && (params.margin_left >= 0);
 101 }
 102
 103 PrintMsg_Print_Params GetCssPrintParams(
 104     blink::WebFrame* frame,
 105     int page_index,
 106     const PrintMsg_Print_Params& page_params) {
 107   PrintMsg_Print_Params page_css_params = page_params;
 108   int dpi = GetDPI(&page_params);
 109
 110   blink::WebSize page_size_in_pixels(
 111       ConvertUnit(page_params.page_size.width(), dpi, kPixelsPerInch),
 112       ConvertUnit(page_params.page_size.height(), dpi, kPixelsPerInch));
 113   int margin_top_in_pixels =
 114       ConvertUnit(page_params.margin_top, dpi, kPixelsPerInch);
 115   int margin_right_in_pixels = ConvertUnit(
 116       page_params.page_size.width() -
 117       page_params.content_size.width() - page_params.margin_left,
 118       dpi, kPixelsPerInch);
 119   int margin_bottom_in_pixels = ConvertUnit(
 120       page_params.page_size.height() -
 121       page_params.content_size.height() - page_params.margin_top,
 122       dpi, kPixelsPerInch);
 123   int margin_left_in_pixels = ConvertUnit(
 124       page_params.margin_left,
 125       dpi, kPixelsPerInch);
 126
 127   blink::WebSize original_page_size_in_pixels = page_size_in_pixels;
 128
 129   if (frame) {
 130     frame->pageSizeAndMarginsInPixels(page_index,
 131                                       page_size_in_pixels,
 132                                       margin_top_in_pixels,
 133                                       margin_right_in_pixels,
 134                                       margin_bottom_in_pixels,
 135                                       margin_left_in_pixels);
 136   }
 137
 138   int new_content_width = page_size_in_pixels.width -
 139                           margin_left_in_pixels - margin_right_in_pixels;
 140   int new_content_height = page_size_in_pixels.height -
 141                            margin_top_in_pixels - margin_bottom_in_pixels;
 142
 143   // Invalid page size and/or margins. We just use the default setting.
 144   if (new_content_width < 1 || new_content_height < 1) {
 145     CHECK(frame != NULL);
 146     page_css_params = GetCssPrintParams(NULL, page_index, page_params);
 147     return page_css_params;
 148   }
 149
 150   page_css_params.content_size = gfx::Size(
 151       ConvertUnit(new_content_width, kPixelsPerInch, dpi),
 152       ConvertUnit(new_content_height, kPixelsPerInch, dpi));
 153
 154   if (original_page_size_in_pixels != page_size_in_pixels) {
 155     page_css_params.page_size = gfx::Size(
 156         ConvertUnit(page_size_in_pixels.width, kPixelsPerInch, dpi),
 157         ConvertUnit(page_size_in_pixels.height, kPixelsPerInch, dpi));
 158   } else {
 159     // Printing frame doesn't have any page size css. Pixels to dpi conversion
 160     // causes rounding off errors. Therefore use the default page size values
 161     // directly.
 162     page_css_params.page_size = page_params.page_size;
 163   }
 164
 165   page_css_params.margin_top =
 166       ConvertUnit(margin_top_in_pixels, kPixelsPerInch, dpi);
 167   page_css_params.margin_left =
 168       ConvertUnit(margin_left_in_pixels, kPixelsPerInch, dpi);
 169   return page_css_params;
 170 }
 171
 172 double FitPrintParamsToPage(const PrintMsg_Print_Params& page_params,
 173                             PrintMsg_Print_Params* params_to_fit) {
 174   double content_width =
 175       static_cast<double>(params_to_fit->content_size.width());
 176   double content_height =
 177       static_cast<double>(params_to_fit->content_size.height());
 178   int default_page_size_height = page_params.page_size.height();
 179   int default_page_size_width = page_params.page_size.width();
 180   int css_page_size_height = params_to_fit->page_size.height();
 181   int css_page_size_width = params_to_fit->page_size.width();
 182
 183   double scale_factor = 1.0f;
 184   if (page_params.page_size == params_to_fit->page_size)
 185     return scale_factor;
 186
 187   if (default_page_size_width < css_page_size_width ||
 188       default_page_size_height < css_page_size_height) {
 189     double ratio_width =
 190         static_cast<double>(default_page_size_width) / css_page_size_width;
 191     double ratio_height =
 192         static_cast<double>(default_page_size_height) / css_page_size_height;
 193     scale_factor = ratio_width < ratio_height ? ratio_width : ratio_height;
 194     content_width *= scale_factor;
 195     content_height *= scale_factor;
 196   }
 197   params_to_fit->margin_top = static_cast<int>(
 198       (default_page_size_height - css_page_size_height * scale_factor) / 2 +
 199       (params_to_fit->margin_top * scale_factor));
 200   params_to_fit->margin_left = static_cast<int>(
 201       (default_page_size_width - css_page_size_width * scale_factor) / 2 +
 202       (params_to_fit->margin_left * scale_factor));
 203   params_to_fit->content_size = gfx::Size(
 204       static_cast<int>(content_width), static_cast<int>(content_height));
 205   params_to_fit->page_size = page_params.page_size;
 206   return scale_factor;
 207 }
 208
 209 void CalculatePageLayoutFromPrintParams(
 210     const PrintMsg_Print_Params& params,
 211     PageSizeMargins* page_layout_in_points) {
 212   int dpi = GetDPI(&params);
 213   int content_width = params.content_size.width();
 214   int content_height = params.content_size.height();
 215
 216   int margin_bottom = params.page_size.height() -
 217                       content_height - params.margin_top;
 218   int margin_right = params.page_size.width() -
 219                       content_width - params.margin_left;
 220
 221   page_layout_in_points->content_width =
 222       ConvertUnit(content_width, dpi, kPointsPerInch);
 223   page_layout_in_points->content_height =
 224       ConvertUnit(content_height, dpi, kPointsPerInch);
 225   page_layout_in_points->margin_top =
 226       ConvertUnit(params.margin_top, dpi, kPointsPerInch);
 227   page_layout_in_points->margin_right =
 228       ConvertUnit(margin_right, dpi, kPointsPerInch);
 229   page_layout_in_points->margin_bottom =
 230       ConvertUnit(margin_bottom, dpi, kPointsPerInch);
 231   page_layout_in_points->margin_left =
 232       ConvertUnit(params.margin_left, dpi, kPointsPerInch);
 233 }
 234
 235 void EnsureOrientationMatches(const PrintMsg_Print_Params& css_params,
 236                               PrintMsg_Print_Params* page_params) {
 237   if ((page_params->page_size.width() > page_params->page_size.height()) ==
 238       (css_params.page_size.width() > css_params.page_size.height())) {
 239     return;
 240   }
 241
 242   // Swap the |width| and |height| values.
 243   page_params->page_size.SetSize(page_params->page_size.height(),
 244                                  page_params->page_size.width());
 245   page_params->content_size.SetSize(page_params->content_size.height(),
 246                                     page_params->content_size.width());
 247   page_params->printable_area.set_size(
 248       gfx::Size(page_params->printable_area.height(),
 249                 page_params->printable_area.width()));
 250 }
 251
 252 void ComputeWebKitPrintParamsInDesiredDpi(
 253     const PrintMsg_Print_Params& print_params,
 254     blink::WebPrintParams* webkit_print_params) {
 255   int dpi = GetDPI(&print_params);
 256   webkit_print_params->printerDPI = dpi;
 257   webkit_print_params->printScalingOption = print_params.print_scaling_option;
 258
 259   webkit_print_params->printContentArea.width =
 260       ConvertUnit(print_params.content_size.width(), dpi,
 261                   print_params.desired_dpi);
 262   webkit_print_params->printContentArea.height =
 263       ConvertUnit(print_params.content_size.height(), dpi,
 264                   print_params.desired_dpi);
 265
 266   webkit_print_params->printableArea.x =
 267       ConvertUnit(print_params.printable_area.x(), dpi,
 268                   print_params.desired_dpi);
 269   webkit_print_params->printableArea.y =
 270       ConvertUnit(print_params.printable_area.y(), dpi,
 271                   print_params.desired_dpi);
 272   webkit_print_params->printableArea.width =
 273       ConvertUnit(print_params.printable_area.width(), dpi,
 274                   print_params.desired_dpi);
 275   webkit_print_params->printableArea.height =
 276       ConvertUnit(print_params.printable_area.height(),
 277                   dpi, print_params.desired_dpi);
 278
 279   webkit_print_params->paperSize.width =
 280       ConvertUnit(print_params.page_size.width(), dpi,
 281                   print_params.desired_dpi);
 282   webkit_print_params->paperSize.height =
 283       ConvertUnit(print_params.page_size.height(), dpi,
 284                   print_params.desired_dpi);
 285 }
 286
 287 blink::WebPlugin* GetPlugin(const blink::WebFrame* frame) {
 288   return frame->document().isPluginDocument() ?
 289          frame->document().to<blink::WebPluginDocument>().plugin() : NULL;
 290 }
 291
 292 bool PrintingNodeOrPdfFrame(const blink::WebFrame* frame,
 293                             const blink::WebNode& node) {
 294   if (!node.isNull())
 295     return true;
 296   blink::WebPlugin* plugin = GetPlugin(frame);
 297   return plugin && plugin->supportsPaginatedPrint();
 298 }
 299
 300 bool PrintingFrameHasPageSizeStyle(blink::WebFrame* frame,
 301                                    int total_page_count) {
 302   if (!frame)
 303     return false;
 304   bool frame_has_custom_page_size_style = false;
 305   for (int i = 0; i < total_page_count; ++i) {
 306     if (frame->hasCustomPageSizeStyle(i)) {
 307       frame_has_custom_page_size_style = true;
 308       break;
 309     }
 310   }
 311   return frame_has_custom_page_size_style;
 312 }
 313
 314 MarginType GetMarginsForPdf(blink::WebFrame* frame,
 315                             const blink::WebNode& node) {
 316   if (frame->isPrintScalingDisabledForPlugin(node))
 317     return NO_MARGINS;
 318   else
 319     return PRINTABLE_AREA_MARGINS;
 320 }
 321
 322 bool FitToPageEnabled(const base::DictionaryValue& job_settings) {
 323   bool fit_to_paper_size = false;
 324   if (!job_settings.GetBoolean(kSettingFitToPageEnabled, &fit_to_paper_size)) {
 325     NOTREACHED();
 326   }
 327   return fit_to_paper_size;
 328 }
 329
 330 PrintMsg_Print_Params CalculatePrintParamsForCss(
 331     blink::WebFrame* frame,
 332     int page_index,
 333     const PrintMsg_Print_Params& page_params,
 334     bool ignore_css_margins,
 335     bool fit_to_page,
 336     double* scale_factor) {
 337   PrintMsg_Print_Params css_params = GetCssPrintParams(frame, page_index,
 338                                                        page_params);
 339
 340   PrintMsg_Print_Params params = page_params;
 341   EnsureOrientationMatches(css_params, &params);
 342
 343   if (ignore_css_margins && fit_to_page)
 344     return params;
 345
 346   PrintMsg_Print_Params result_params = css_params;
 347   if (ignore_css_margins) {
 348     result_params.margin_top = params.margin_top;
 349     result_params.margin_left = params.margin_left;
 350
 351     DCHECK(!fit_to_page);
 352     // Since we are ignoring the margins, the css page size is no longer
 353     // valid.
 354     int default_margin_right = params.page_size.width() -
 355         params.content_size.width() - params.margin_left;
 356     int default_margin_bottom = params.page_size.height() -
 357         params.content_size.height() - params.margin_top;
 358     result_params.content_size = gfx::Size(
 359         result_params.page_size.width() - result_params.margin_left -
 360             default_margin_right,
 361         result_params.page_size.height() - result_params.margin_top -
 362             default_margin_bottom);
 363   }
 364
 365   if (fit_to_page) {
 366     double factor = FitPrintParamsToPage(params, &result_params);
 367     if (scale_factor)
 368       *scale_factor = factor;
 369   }
 370   return result_params;
 371 }
 372
 373 bool IsPrintPreviewEnabled() {
 374   return false;
 375 }
 376
 377 bool IsPrintThrottlingDisabled() {
 378   return true;
 379 }
 380
 381 }  // namespace
 382
 383 FrameReference::FrameReference(blink::WebLocalFrame* frame) {
 384   Reset(frame);
 385 }
 386
 387 FrameReference::FrameReference() {
 388   Reset(NULL);
 389 }
 390
 391 FrameReference::~FrameReference() {
 392 }
 393
 394 void FrameReference::Reset(blink::WebLocalFrame* frame) {
 395   if (frame) {
 396     view_ = frame->view();
 397     frame_ = frame;
 398   } else {
 399     view_ = NULL;
 400     frame_ = NULL;
 401   }
 402 }
 403
 404 blink::WebLocalFrame* FrameReference::GetFrame() {
 405   if (view_ == NULL || frame_ == NULL)
 406     return NULL;
 407   for (blink::WebFrame* frame = view_->mainFrame(); frame != NULL;
 408            frame = frame->traverseNext(false)) {
 409     if (frame == frame_)
 410       return frame_;
 411   }
 412   return NULL;
 413 }
 414
 415 blink::WebView* FrameReference::view() {
 416   return view_;
 417 }
 418
 419 // static - Not anonymous so that platform implementations can use it.
 420 void PrintWebViewHelper::PrintHeaderAndFooter(
 421     blink::WebCanvas* canvas,
 422     int page_number,
 423     int total_pages,
 424     float webkit_scale_factor,
 425     const PageSizeMargins& page_layout,
 426     const base::DictionaryValue& header_footer_info,
 427     const PrintMsg_Print_Params& params) {
 428 #if 0
 429   // TODO(sgurun) android_webview hack
 430   skia::VectorPlatformDeviceSkia* device =
 431       static_cast<skia::VectorPlatformDeviceSkia*>(canvas->getTopDevice());
 432   device->setDrawingArea(SkPDFDevice::kMargin_DrawingArea);
 433
 434   SkAutoCanvasRestore auto_restore(canvas, true);
 435   canvas->scale(1 / webkit_scale_factor, 1 / webkit_scale_factor);
 436
 437   blink::WebSize page_size(page_layout.margin_left + page_layout.margin_right +
 438                             page_layout.content_width,
 439                             page_layout.margin_top + page_layout.margin_bottom +
 440                             page_layout.content_height);
 441
 442   blink::WebView* web_view = blink::WebView::create(NULL);
 443   web_view->settings()->setJavaScriptEnabled(true);
 444   blink::WebFrame* frame = blink::WebLocalFrame::create(NULL)
 445   web_view->setMainFrame(web_frame);
 446
 447   base::StringValue html(
 448       ResourceBundle::GetSharedInstance().GetLocalizedString(
 449           IDR_PRINT_PREVIEW_PAGE));
 450   // Load page with script to avoid async operations.
 451   ExecuteScript(frame, kPageLoadScriptFormat, html);
 452
 453   scoped_ptr<base::DictionaryValue> options(header_footer_info.DeepCopy());
 454   options->SetDouble("width", page_size.width);
 455   options->SetDouble("height", page_size.height);
 456   options->SetDouble("topMargin", page_layout.margin_top);
 457   options->SetDouble("bottomMargin", page_layout.margin_bottom);
 458   options->SetString("pageNumber",
 459                      base::StringPrintf("%d/%d", page_number, total_pages));
 460
 461   ExecuteScript(frame, kPageSetupScriptFormat, *options);
 462
 463   blink::WebPrintParams webkit_params(page_size);
 464   webkit_params.printerDPI = GetDPI(&params);
 465
 466   frame->printBegin(webkit_params, WebKit::WebNode(), NULL);
 467   frame->printPage(0, canvas);
 468   frame->printEnd();
 469
 470   web_view->close();
 471   frame->close();
 472
 473   device->setDrawingArea(SkPDFDevice::kContent_DrawingArea);
 474 #endif
 475 }
 476
 477 // static - Not anonymous so that platform implementations can use it.
 478 float PrintWebViewHelper::RenderPageContent(blink::WebFrame* frame,
 479                                             int page_number,
 480                                             const gfx::Rect& canvas_area,
 481                                             const gfx::Rect& content_area,
 482                                             double scale_factor,
 483                                             blink::WebCanvas* canvas) {
 484   SkAutoCanvasRestore auto_restore(canvas, true);
 485   if (content_area != canvas_area) {
 486     canvas->translate((content_area.x() - canvas_area.x()) / scale_factor,
 487                       (content_area.y() - canvas_area.y()) / scale_factor);
 488     SkRect clip_rect(
 489         SkRect::MakeXYWH(content_area.origin().x() / scale_factor,
 490                          content_area.origin().y() / scale_factor,
 491                          content_area.size().width() / scale_factor,
 492                          content_area.size().height() / scale_factor));
 493     SkIRect clip_int_rect;
 494     clip_rect.roundOut(&clip_int_rect);
 495     SkRegion clip_region(clip_int_rect);
 496     canvas->setClipRegion(clip_region);
 497   }
 498   return frame->printPage(page_number, canvas);
 499 }
 500
 501 // Class that calls the Begin and End print functions on the frame and changes
 502 // the size of the view temporarily to support full page printing..
 503 class PrepareFrameAndViewForPrint : public blink::WebViewClient,
 504                                     public blink::WebFrameClient {
 505  public:
 506   PrepareFrameAndViewForPrint(const PrintMsg_Print_Params& params,
 507                               blink::WebLocalFrame* frame,
 508                               const blink::WebNode& node,
 509                               bool ignore_css_margins);
 510   virtual ~PrepareFrameAndViewForPrint();
 511
 512   // Optional. Replaces |frame_| with selection if needed. Will call |on_ready|
 513   // when completed.
 514   void CopySelectionIfNeeded(const WebPreferences& preferences,
 515                              const base::Closure& on_ready);
 516
 517   // Prepares frame for printing.
 518   void StartPrinting();
 519
 520   blink::WebLocalFrame* frame() {
 521     return frame_.GetFrame();
 522   }
 523
 524   const blink::WebNode& node() const {
 525     return node_to_print_;
 526   }
 527
 528   int GetExpectedPageCount() const {
 529     return expected_pages_count_;
 530   }
 531
 532   gfx::Size GetPrintCanvasSize() const;
 533
 534   void FinishPrinting();
 535
 536   bool IsLoadingSelection() {
 537     // It's not selection if not |owns_web_view_|.
 538     return owns_web_view_ && frame() && frame()->isLoading();
 539   }
 540
 541   // TODO(ojan): Remove this override and have this class use a non-null
 542   // layerTreeView.
 543   // blink::WebViewClient override:
 544   virtual bool allowsBrokenNullLayerTreeView() const;
 545
 546  protected:
 547   // blink::WebViewClient override:
 548   virtual void didStopLoading();
 549
 550   // blink::WebFrameClient override:
 551   virtual blink::WebFrame* createChildFrame(blink::WebLocalFrame* parent,
 552                                             const blink::WebString& name);
 553   virtual void frameDetached(blink::WebFrame* frame);
 554
 555  private:
 556   void CallOnReady();
 557   void ResizeForPrinting();
 558   void RestoreSize();
 559   void CopySelection(const WebPreferences& preferences);
 560
 561   base::WeakPtrFactory<PrepareFrameAndViewForPrint> weak_ptr_factory_;
 562
 563   FrameReference frame_;
 564   blink::WebNode node_to_print_;
 565   bool owns_web_view_;
 566   blink::WebPrintParams web_print_params_;
 567   gfx::Size prev_view_size_;
 568   gfx::Size prev_scroll_offset_;
 569   int expected_pages_count_;
 570   base::Closure on_ready_;
 571   bool should_print_backgrounds_;
 572   bool should_print_selection_only_;
 573   bool is_printing_started_;
 574
 575   DISALLOW_COPY_AND_ASSIGN(PrepareFrameAndViewForPrint);
 576 };
 577
 578 PrepareFrameAndViewForPrint::PrepareFrameAndViewForPrint(
 579     const PrintMsg_Print_Params& params,
 580     blink::WebLocalFrame* frame,
 581     const blink::WebNode& node,
 582     bool ignore_css_margins)
 583     : weak_ptr_factory_(this),
 584       frame_(frame),
 585       node_to_print_(node),
 586       owns_web_view_(false),
 587       expected_pages_count_(0),
 588       should_print_backgrounds_(params.should_print_backgrounds),
 589       should_print_selection_only_(params.selection_only),
 590       is_printing_started_(false) {
 591   PrintMsg_Print_Params print_params = params;
 592   if (!should_print_selection_only_ ||
 593       !PrintingNodeOrPdfFrame(frame, node_to_print_)) {
 594     bool fit_to_page = ignore_css_margins &&
 595                        print_params.print_scaling_option ==
 596                             blink::WebPrintScalingOptionFitToPrintableArea;
 597     ComputeWebKitPrintParamsInDesiredDpi(params, &web_print_params_);
 598     frame->printBegin(web_print_params_, node_to_print_);
 599     print_params = CalculatePrintParamsForCss(frame, 0, print_params,
 600                                               ignore_css_margins, fit_to_page,
 601                                               NULL);
 602     frame->printEnd();
 603   }
 604   ComputeWebKitPrintParamsInDesiredDpi(print_params, &web_print_params_);
 605 }
 606
 607 PrepareFrameAndViewForPrint::~PrepareFrameAndViewForPrint() {
 608   FinishPrinting();
 609 }
 610
 611 void PrepareFrameAndViewForPrint::ResizeForPrinting() {
 612   // Layout page according to printer page size. Since WebKit shrinks the
 613   // size of the page automatically (from 125% to 200%) we trick it to
 614   // think the page is 125% larger so the size of the page is correct for
 615   // minimum (default) scaling.
 616   // This is important for sites that try to fill the page.
 617   gfx::Size print_layout_size(web_print_params_.printContentArea.width,
 618                               web_print_params_.printContentArea.height);
 619   print_layout_size.set_height(
 620       static_cast<int>(static_cast<double>(print_layout_size.height()) * 1.25));
 621
 622   if (!frame())
 623     return;
 624   blink::WebView* web_view = frame_.view();
 625   // Backup size and offset.
 626   if (blink::WebFrame* web_frame = web_view->mainFrame())
 627     prev_scroll_offset_ = web_frame->scrollOffset();
 628   prev_view_size_ = web_view->size();
 629
 630   web_view->resize(print_layout_size);
 631 }
 632
 633
 634 void PrepareFrameAndViewForPrint::StartPrinting() {
 635   ResizeForPrinting();
 636   blink::WebView* web_view = frame_.view();
 637   web_view->settings()->setShouldPrintBackgrounds(should_print_backgrounds_);
 638   expected_pages_count_ =
 639       frame()->printBegin(web_print_params_, node_to_print_);
 640   is_printing_started_ = true;
 641 }
 642
 643 void PrepareFrameAndViewForPrint::CopySelectionIfNeeded(
 644     const WebPreferences& preferences,
 645     const base::Closure& on_ready) {
 646   on_ready_ = on_ready;
 647   if (should_print_selection_only_)
 648     CopySelection(preferences);
 649   else
 650     didStopLoading();
 651 }
 652
 653 void PrepareFrameAndViewForPrint::CopySelection(
 654     const WebPreferences& preferences) {
 655   ResizeForPrinting();
 656   std::string url_str = "data:text/html;charset=utf-8,";
 657   url_str.append(
 658       net::EscapeQueryParamValue(frame()->selectionAsMarkup().utf8(), false));
 659   RestoreSize();
 660   // Create a new WebView with the same settings as the current display one.
 661   // Except that we disable javascript (don't want any active content running
 662   // on the page).
 663   WebPreferences prefs = preferences;
 664   prefs.javascript_enabled = false;
 665   prefs.java_enabled = false;
 666
 667   blink::WebView* web_view = blink::WebView::create(this);
 668   owns_web_view_ = true;
 669   content::RenderView::ApplyWebPreferences(prefs, web_view);
 670   web_view->setMainFrame(blink::WebLocalFrame::create(this));
 671   frame_.Reset(web_view->mainFrame()->toWebLocalFrame());
 672   node_to_print_.reset();
 673
 674   // When loading is done this will call didStopLoading() and that will do the
 675   // actual printing.
 676   frame()->loadRequest(blink::WebURLRequest(GURL(url_str)));
 677 }
 678
 679 bool PrepareFrameAndViewForPrint::allowsBrokenNullLayerTreeView() const {
 680   return true;
 681 }
 682
 683 void PrepareFrameAndViewForPrint::didStopLoading() {
 684   DCHECK(!on_ready_.is_null());
 685   // Don't call callback here, because it can delete |this| and WebView that is
 686   // called didStopLoading.
 687   base::MessageLoop::current()->PostTask(
 688       FROM_HERE,
 689       base::Bind(&PrepareFrameAndViewForPrint::CallOnReady,
 690                  weak_ptr_factory_.GetWeakPtr()));
 691 }
 692
 693 blink::WebFrame* PrepareFrameAndViewForPrint::createChildFrame(
 694     blink::WebLocalFrame* parent,
 695     const blink::WebString& name) {
 696   blink::WebFrame* frame = blink::WebLocalFrame::create(this);
 697   parent->appendChild(frame);
 698   return frame;
 699 }
 700
 701 void PrepareFrameAndViewForPrint::frameDetached(blink::WebFrame* frame) {
 702   if (frame->parent())
 703     frame->parent()->removeChild(frame);
 704   frame->close();
 705 }
 706
 707 void PrepareFrameAndViewForPrint::CallOnReady() {
 708   return on_ready_.Run();  // Can delete |this|.
 709 }
 710
 711 gfx::Size PrepareFrameAndViewForPrint::GetPrintCanvasSize() const {
 712   DCHECK(is_printing_started_);
 713   return gfx::Size(web_print_params_.printContentArea.width,
 714                    web_print_params_.printContentArea.height);
 715 }
 716
 717 void PrepareFrameAndViewForPrint::RestoreSize() {
 718   if (frame()) {
 719     blink::WebView* web_view = frame_.GetFrame()->view();
 720     web_view->resize(prev_view_size_);
 721     if (blink::WebFrame* web_frame = web_view->mainFrame())
 722       web_frame->setScrollOffset(prev_scroll_offset_);
 723   }
 724 }
 725
 726 void PrepareFrameAndViewForPrint::FinishPrinting() {
 727   blink::WebFrame* frame = frame_.GetFrame();
 728   if (frame) {
 729     blink::WebView* web_view = frame->view();
 730     if (is_printing_started_) {
 731       is_printing_started_ = false;
 732       frame->printEnd();
 733       if (!owns_web_view_) {
 734         web_view->settings()->setShouldPrintBackgrounds(false);
 735         RestoreSize();
 736       }
 737     }
 738     if (owns_web_view_) {
 739       DCHECK(!frame->isLoading());
 740       owns_web_view_ = false;
 741       web_view->close();
 742     }
 743   }
 744   frame_.Reset(NULL);
 745   on_ready_.Reset();
 746 }
 747
 748 PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
 749     : content::RenderViewObserver(render_view),
 750       content::RenderViewObserverTracker<PrintWebViewHelper>(render_view),
 751       reset_prep_frame_view_(false),
 752       is_preview_enabled_(IsPrintPreviewEnabled()),
 753       is_scripted_print_throttling_disabled_(IsPrintThrottlingDisabled()),
 754       is_print_ready_metafile_sent_(false),
 755       ignore_css_margins_(false),
 756       user_cancelled_scripted_print_count_(0),
 757       is_scripted_printing_blocked_(false),
 758       notify_browser_of_print_failure_(true),
 759       print_for_preview_(false),
 760       print_node_in_progress_(false),
 761       is_loading_(false),
 762       is_scripted_preview_delayed_(false),
 763       weak_ptr_factory_(this) {
 764   // TODO(sgurun) enable window.print() for webview crbug.com/322303
 765   SetScriptedPrintBlocked(true);
 766 }
 767
 768 PrintWebViewHelper::~PrintWebViewHelper() {}
 769
 770 bool PrintWebViewHelper::IsScriptInitiatedPrintAllowed(
 771     blink::WebFrame* frame, bool user_initiated) {
 772 #if defined(OS_ANDROID)
 773   return false;
 774 #endif  // defined(OS_ANDROID)
 775   if (is_scripted_printing_blocked_)
 776     return false;
 777   // If preview is enabled, then the print dialog is tab modal, and the user
 778   // can always close the tab on a mis-behaving page (the system print dialog
 779   // is app modal). If the print was initiated through user action, don't
 780   // throttle. Or, if the command line flag to skip throttling has been set.
 781   if (!is_scripted_print_throttling_disabled_ &&
 782       !is_preview_enabled_ &&
 783       !user_initiated)
 784     return !IsScriptInitiatedPrintTooFrequent(frame);
 785   return true;
 786 }
 787
 788 void PrintWebViewHelper::DidStartLoading() {
 789   is_loading_ = true;
 790 }
 791
 792 void PrintWebViewHelper::DidStopLoading() {
 793   is_loading_ = false;
 794   ShowScriptedPrintPreview();
 795 }
 796
 797 // Prints |frame| which called window.print().
 798 void PrintWebViewHelper::PrintPage(blink::WebLocalFrame* frame,
 799                                    bool user_initiated) {
 800   DCHECK(frame);
 801
 802 #if !defined(OS_ANDROID)
 803   // TODO(sgurun) android_webview hack
 804   // Allow Prerendering to cancel this print request if necessary.
 805   if (prerender::PrerenderHelper::IsPrerendering(render_view())) {
 806     Send(new ChromeViewHostMsg_CancelPrerenderForPrinting(routing_id()));
 807     return;
 808   }
 809 #endif  // !defined(OS_ANDROID)
 810
 811   if (!IsScriptInitiatedPrintAllowed(frame, user_initiated))
 812     return;
 813   IncrementScriptedPrintCount();
 814
 815   if (is_preview_enabled_) {
 816     print_preview_context_.InitWithFrame(frame);
 817     RequestPrintPreview(PRINT_PREVIEW_SCRIPTED);
 818   } else {
 819     Print(frame, blink::WebNode());
 820   }
 821 }
 822
 823 bool PrintWebViewHelper::OnMessageReceived(const IPC::Message& message) {
 824   bool handled = true;
 825   IPC_BEGIN_MESSAGE_MAP(PrintWebViewHelper, message)
 826     IPC_MESSAGE_HANDLER(PrintMsg_PrintPages, OnPrintPages)
 827     IPC_MESSAGE_HANDLER(PrintMsg_PrintForSystemDialog, OnPrintForSystemDialog)
 828     IPC_MESSAGE_HANDLER(PrintMsg_InitiatePrintPreview, OnInitiatePrintPreview)
 829     IPC_MESSAGE_HANDLER(PrintMsg_PrintPreview, OnPrintPreview)
 830     IPC_MESSAGE_HANDLER(PrintMsg_PrintForPrintPreview, OnPrintForPrintPreview)
 831     IPC_MESSAGE_HANDLER(PrintMsg_PrintingDone, OnPrintingDone)
 832     IPC_MESSAGE_HANDLER(PrintMsg_ResetScriptedPrintCount,
 833                         ResetScriptedPrintCount)
 834     IPC_MESSAGE_HANDLER(PrintMsg_SetScriptedPrintingBlocked,
 835                         SetScriptedPrintBlocked)
 836     IPC_MESSAGE_UNHANDLED(handled = false)
 837     IPC_END_MESSAGE_MAP()
 838   return handled;
 839 }
 840
 841 void PrintWebViewHelper::OnPrintForPrintPreview(
 842     const base::DictionaryValue& job_settings) {
 843   DCHECK(is_preview_enabled_);
 844   // If still not finished with earlier print request simply ignore.
 845   if (prep_frame_view_)
 846     return;
 847
 848   if (!render_view()->GetWebView())
 849     return;
 850   blink::WebFrame* main_frame = render_view()->GetWebView()->mainFrame();
 851   if (!main_frame)
 852     return;
 853
 854   blink::WebDocument document = main_frame->document();
 855   // <object> with id="pdf-viewer" is created in
 856   // chrome/browser/resources/print_preview/print_preview.js
 857   blink::WebElement pdf_element = document.getElementById("pdf-viewer");
 858   if (pdf_element.isNull()) {
 859     NOTREACHED();
 860     return;
 861   }
 862
 863   // Set |print_for_preview_| flag and autoreset it to back to original
 864   // on return.
 865   base::AutoReset<bool> set_printing_flag(&print_for_preview_, true);
 866
 867   blink::WebLocalFrame* pdf_frame = pdf_element.document().frame();
 868   if (!UpdatePrintSettings(pdf_frame, pdf_element, job_settings)) {
 869     LOG(ERROR) << "UpdatePrintSettings failed";
 870     DidFinishPrinting(FAIL_PRINT);
 871     return;
 872   }
 873
 874   // Print page onto entire page not just printable area. Preview PDF already
 875   // has content in correct position taking into account page size and printable
 876   // area.
 877   // TODO(vitalybuka) : Make this consistent on all platform. This change
 878   // affects Windows only. On Linux and OSX RenderPagesForPrint does not use
 879   // printable_area. Also we can't change printable_area deeper inside
 880   // RenderPagesForPrint for Windows, because it's used also by native
 881   // printing and it expects real printable_area value.
 882   // See http://crbug.com/123408
 883   PrintMsg_Print_Params& print_params = print_pages_params_->params;
 884   print_params.printable_area = gfx::Rect(print_params.page_size);
 885
 886   // Render Pages for printing.
 887   if (!RenderPagesForPrint(pdf_frame, pdf_element)) {
 888     LOG(ERROR) << "RenderPagesForPrint failed";
 889     DidFinishPrinting(FAIL_PRINT);
 890   }
 891 }
 892
 893 bool PrintWebViewHelper::GetPrintFrame(blink::WebLocalFrame** frame) {
 894   DCHECK(frame);
 895   blink::WebView* webView = render_view()->GetWebView();
 896   DCHECK(webView);
 897   if (!webView)
 898     return false;
 899
 900   // If the user has selected text in the currently focused frame we print
 901   // only that frame (this makes print selection work for multiple frames).
 902   blink::WebLocalFrame* focusedFrame =
 903       webView->focusedFrame()->toWebLocalFrame();
 904   *frame = focusedFrame->hasSelection()
 905                ? focusedFrame
 906                : webView->mainFrame()->toWebLocalFrame();
 907   return true;
 908 }
 909
 910 void PrintWebViewHelper::OnPrintPages() {
 911   blink::WebLocalFrame* frame;
 912   if (GetPrintFrame(&frame))
 913     Print(frame, blink::WebNode());
 914 }
 915
 916 void PrintWebViewHelper::OnPrintForSystemDialog() {
 917   blink::WebLocalFrame* frame = print_preview_context_.source_frame();
 918   if (!frame) {
 919     NOTREACHED();
 920     return;
 921   }
 922
 923   Print(frame, print_preview_context_.source_node());
 924 }
 925
 926 void PrintWebViewHelper::GetPageSizeAndContentAreaFromPageLayout(
 927     const PageSizeMargins& page_layout_in_points,
 928     gfx::Size* page_size,
 929     gfx::Rect* content_area) {
 930   *page_size = gfx::Size(
 931       page_layout_in_points.content_width +
 932           page_layout_in_points.margin_right +
 933           page_layout_in_points.margin_left,
 934       page_layout_in_points.content_height +
 935           page_layout_in_points.margin_top +
 936           page_layout_in_points.margin_bottom);
 937   *content_area = gfx::Rect(page_layout_in_points.margin_left,
 938                             page_layout_in_points.margin_top,
 939                             page_layout_in_points.content_width,
 940                             page_layout_in_points.content_height);
 941 }
 942
 943 void PrintWebViewHelper::UpdateFrameMarginsCssInfo(
 944     const base::DictionaryValue& settings) {
 945   int margins_type = 0;
 946   if (!settings.GetInteger(kSettingMarginsType, &margins_type))
 947     margins_type = DEFAULT_MARGINS;
 948   ignore_css_margins_ = (margins_type != DEFAULT_MARGINS);
 949 }
 950
 951 bool PrintWebViewHelper::IsPrintToPdfRequested(
 952     const base::DictionaryValue& job_settings) {
 953   bool print_to_pdf = false;
 954   if (!job_settings.GetBoolean(kSettingPrintToPDF, &print_to_pdf))
 955     NOTREACHED();
 956   return print_to_pdf;
 957 }
 958
 959 blink::WebPrintScalingOption PrintWebViewHelper::GetPrintScalingOption(
 960     bool source_is_html, const base::DictionaryValue& job_settings,
 961     const PrintMsg_Print_Params& params) {
 962   DCHECK(!print_for_preview_);
 963
 964   if (params.print_to_pdf)
 965     return blink::WebPrintScalingOptionSourceSize;
 966
 967   if (!source_is_html) {
 968     if (!FitToPageEnabled(job_settings))
 969       return blink::WebPrintScalingOptionNone;
 970
 971     bool no_plugin_scaling =
 972         print_preview_context_.source_frame()->isPrintScalingDisabledForPlugin(
 973             print_preview_context_.source_node());
 974
 975     if (params.is_first_request && no_plugin_scaling)
 976       return blink::WebPrintScalingOptionNone;
 977   }
 978   return blink::WebPrintScalingOptionFitToPrintableArea;
 979 }
 980
 981 void PrintWebViewHelper::OnPrintPreview(const base::DictionaryValue& settings) {
 982   DCHECK(is_preview_enabled_);
 983   print_preview_context_.OnPrintPreview();
 984
 985   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
 986                             PREVIEW_EVENT_REQUESTED, PREVIEW_EVENT_MAX);
 987
 988   if (!UpdatePrintSettings(print_preview_context_.source_frame(),
 989                            print_preview_context_.source_node(), settings)) {
 990     if (print_preview_context_.last_error() != PREVIEW_ERROR_BAD_SETTING) {
 991       Send(new PrintHostMsg_PrintPreviewInvalidPrinterSettings(
 992           routing_id(), print_pages_params_->params.document_cookie));
 993       notify_browser_of_print_failure_ = false;  // Already sent.
 994     }
 995     DidFinishPrinting(FAIL_PREVIEW);
 996     return;
 997   }
 998
 999   // If we are previewing a pdf and the print scaling is disabled, send a
1000   // message to browser.
1001   if (print_pages_params_->params.is_first_request &&
1002       !print_preview_context_.IsModifiable() &&
1003       print_preview_context_.source_frame()->isPrintScalingDisabledForPlugin(
1004           print_preview_context_.source_node())) {
1005     Send(new PrintHostMsg_PrintPreviewScalingDisabled(routing_id()));
1006   }
1007
1008   is_print_ready_metafile_sent_ = false;
1009
1010   // PDF printer device supports alpha blending.
1011   print_pages_params_->params.supports_alpha_blend = true;
1012
1013   bool generate_draft_pages = false;
1014   if (!settings.GetBoolean(kSettingGenerateDraftData,
1015                            &generate_draft_pages)) {
1016     NOTREACHED();
1017   }
1018   print_preview_context_.set_generate_draft_pages(generate_draft_pages);
1019
1020   PrepareFrameForPreviewDocument();
1021 }
1022
1023 void PrintWebViewHelper::PrepareFrameForPreviewDocument() {
1024   reset_prep_frame_view_ = false;
1025
1026   if (!print_pages_params_ || CheckForCancel()) {
1027     DidFinishPrinting(FAIL_PREVIEW);
1028     return;
1029   }
1030
1031   // Don't reset loading frame or WebKit will fail assert. Just retry when
1032   // current selection is loaded.
1033   if (prep_frame_view_ && prep_frame_view_->IsLoadingSelection()) {
1034     reset_prep_frame_view_ = true;
1035     return;
1036   }
1037
1038   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1039   prep_frame_view_.reset(
1040       new PrepareFrameAndViewForPrint(print_params,
1041                                       print_preview_context_.source_frame(),
1042                                       print_preview_context_.source_node(),
1043                                       ignore_css_margins_));
1044   prep_frame_view_->CopySelectionIfNeeded(
1045       render_view()->GetWebkitPreferences(),
1046       base::Bind(&PrintWebViewHelper::OnFramePreparedForPreviewDocument,
1047                  base::Unretained(this)));
1048 }
1049
1050 void PrintWebViewHelper::OnFramePreparedForPreviewDocument() {
1051   if (reset_prep_frame_view_) {
1052     PrepareFrameForPreviewDocument();
1053     return;
1054   }
1055   DidFinishPrinting(CreatePreviewDocument() ? OK : FAIL_PREVIEW);
1056 }
1057
1058 bool PrintWebViewHelper::CreatePreviewDocument() {
1059   if (!print_pages_params_ || CheckForCancel())
1060     return false;
1061
1062   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
1063                             PREVIEW_EVENT_CREATE_DOCUMENT, PREVIEW_EVENT_MAX);
1064
1065   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1066   const std::vector<int>& pages = print_pages_params_->pages;
1067
1068   if (!print_preview_context_.CreatePreviewDocument(prep_frame_view_.release(),
1069                                                     pages)) {
1070     return false;
1071   }
1072
1073   PageSizeMargins default_page_layout;
1074   ComputePageLayoutInPointsForCss(print_preview_context_.prepared_frame(), 0,
1075                                   print_params, ignore_css_margins_, NULL,
1076                                   &default_page_layout);
1077
1078   bool has_page_size_style = PrintingFrameHasPageSizeStyle(
1079       print_preview_context_.prepared_frame(),
1080       print_preview_context_.total_page_count());
1081   int dpi = GetDPI(&print_params);
1082
1083   gfx::Rect printable_area_in_points(
1084       ConvertUnit(print_params.printable_area.x(), dpi, kPointsPerInch),
1085       ConvertUnit(print_params.printable_area.y(), dpi, kPointsPerInch),
1086       ConvertUnit(print_params.printable_area.width(), dpi, kPointsPerInch),
1087       ConvertUnit(print_params.printable_area.height(), dpi, kPointsPerInch));
1088
1089   // Margins: Send default page layout to browser process.
1090   Send(new PrintHostMsg_DidGetDefaultPageLayout(routing_id(),
1091                                                 default_page_layout,
1092                                                 printable_area_in_points,
1093                                                 has_page_size_style));
1094
1095   PrintHostMsg_DidGetPreviewPageCount_Params params;
1096   params.page_count = print_preview_context_.total_page_count();
1097   params.is_modifiable = print_preview_context_.IsModifiable();
1098   params.document_cookie = print_params.document_cookie;
1099   params.preview_request_id = print_params.preview_request_id;
1100   params.clear_preview_data = print_preview_context_.generate_draft_pages();
1101   Send(new PrintHostMsg_DidGetPreviewPageCount(routing_id(), params));
1102   if (CheckForCancel())
1103     return false;
1104
1105   while (!print_preview_context_.IsFinalPageRendered()) {
1106     int page_number = print_preview_context_.GetNextPageNumber();
1107     DCHECK_GE(page_number, 0);
1108     if (!RenderPreviewPage(page_number, print_params))
1109       return false;
1110
1111     if (CheckForCancel())
1112       return false;
1113
1114     // We must call PrepareFrameAndViewForPrint::FinishPrinting() (by way of
1115     // print_preview_context_.AllPagesRendered()) before calling
1116     // FinalizePrintReadyDocument() when printing a PDF because the plugin
1117     // code does not generate output until we call FinishPrinting().  We do not
1118     // generate draft pages for PDFs, so IsFinalPageRendered() and
1119     // IsLastPageOfPrintReadyMetafile() will be true in the same iteration of
1120     // the loop.
1121     if (print_preview_context_.IsFinalPageRendered())
1122       print_preview_context_.AllPagesRendered();
1123
1124     if (print_preview_context_.IsLastPageOfPrintReadyMetafile()) {
1125       DCHECK(print_preview_context_.IsModifiable() ||
1126              print_preview_context_.IsFinalPageRendered());
1127       if (!FinalizePrintReadyDocument())
1128         return false;
1129     }
1130   }
1131   print_preview_context_.Finished();
1132   return true;
1133 }
1134
1135 bool PrintWebViewHelper::FinalizePrintReadyDocument() {
1136   DCHECK(!is_print_ready_metafile_sent_);
1137   print_preview_context_.FinalizePrintReadyDocument();
1138
1139   // Get the size of the resulting metafile.
1140   PreviewMetafile* metafile = print_preview_context_.metafile();
1141   uint32 buf_size = metafile->GetDataSize();
1142   DCHECK_GT(buf_size, 0u);
1143
1144   PrintHostMsg_DidPreviewDocument_Params preview_params;
1145   preview_params.reuse_existing_data = false;
1146   preview_params.data_size = buf_size;
1147   preview_params.document_cookie = print_pages_params_->params.document_cookie;
1148   preview_params.expected_pages_count =
1149       print_preview_context_.total_page_count();
1150   preview_params.modifiable = print_preview_context_.IsModifiable();
1151   preview_params.preview_request_id =
1152       print_pages_params_->params.preview_request_id;
1153
1154   // Ask the browser to create the shared memory for us.
1155   if (!CopyMetafileDataToSharedMem(metafile,
1156                                    &(preview_params.metafile_data_handle))) {
1157     LOG(ERROR) << "CopyMetafileDataToSharedMem failed";
1158     print_preview_context_.set_error(PREVIEW_ERROR_METAFILE_COPY_FAILED);
1159     return false;
1160   }
1161   is_print_ready_metafile_sent_ = true;
1162
1163   Send(new PrintHostMsg_MetafileReadyForPrinting(routing_id(), preview_params));
1164   return true;
1165 }
1166
1167 void PrintWebViewHelper::OnPrintingDone(bool success) {
1168   notify_browser_of_print_failure_ = false;
1169   if (!success)
1170     LOG(ERROR) << "Failure in OnPrintingDone";
1171   DidFinishPrinting(success ? OK : FAIL_PRINT);
1172 }
1173
1174 void PrintWebViewHelper::SetScriptedPrintBlocked(bool blocked) {
1175   is_scripted_printing_blocked_ = blocked;
1176 }
1177
1178 void PrintWebViewHelper::OnInitiatePrintPreview(bool selection_only) {
1179   DCHECK(is_preview_enabled_);
1180   blink::WebLocalFrame* frame = NULL;
1181   GetPrintFrame(&frame);
1182   DCHECK(frame);
1183   print_preview_context_.InitWithFrame(frame);
1184   RequestPrintPreview(selection_only ?
1185                       PRINT_PREVIEW_USER_INITIATED_SELECTION :
1186                       PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME);
1187 }
1188
1189 bool PrintWebViewHelper::IsPrintingEnabled() {
1190   bool result = false;
1191   Send(new PrintHostMsg_IsPrintingEnabled(routing_id(), &result));
1192   return result;
1193 }
1194
1195 void PrintWebViewHelper::PrintNode(const blink::WebNode& node) {
1196   if (node.isNull() || !node.document().frame()) {
1197     // This can occur when the context menu refers to an invalid WebNode.
1198     // See http://crbug.com/100890#c17 for a repro case.
1199     return;
1200   }
1201
1202   if (print_node_in_progress_) {
1203     // This can happen as a result of processing sync messages when printing
1204     // from ppapi plugins. It's a rare case, so its OK to just fail here.
1205     // See http://crbug.com/159165.
1206     return;
1207   }
1208
1209   print_node_in_progress_ = true;
1210
1211   // Make a copy of the node, in case RenderView::OnContextMenuClosed resets
1212   // its |context_menu_node_|.
1213   if (is_preview_enabled_) {
1214     print_preview_context_.InitWithNode(node);
1215     RequestPrintPreview(PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE);
1216   } else {
1217     blink::WebNode duplicate_node(node);
1218     Print(duplicate_node.document().frame(), duplicate_node);
1219   }
1220
1221   print_node_in_progress_ = false;
1222 }
1223
1224 void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
1225                                const blink::WebNode& node) {
1226   // If still not finished with earlier print request simply ignore.
1227   if (prep_frame_view_)
1228     return;
1229
1230   FrameReference frame_ref(frame);
1231
1232   int expected_page_count = 0;
1233   if (!CalculateNumberOfPages(frame, node, &expected_page_count)) {
1234     DidFinishPrinting(FAIL_PRINT_INIT);
1235     return;  // Failed to init print page settings.
1236   }
1237
1238   // Some full screen plugins can say they don't want to print.
1239   if (!expected_page_count) {
1240     DidFinishPrinting(FAIL_PRINT);
1241     return;
1242   }
1243
1244 #if !defined(OS_ANDROID)
1245   // TODO(sgurun) android_webview hack
1246   // Ask the browser to show UI to retrieve the final print settings.
1247   if (!GetPrintSettingsFromUser(frame_ref.GetFrame(), node,
1248                                 expected_page_count)) {
1249     DidFinishPrinting(OK);  // Release resources and fail silently.
1250     return;
1251   }
1252 #endif  // !defined(OS_ANDROID)
1253
1254   // Render Pages for printing.
1255   if (!RenderPagesForPrint(frame_ref.GetFrame(), node)) {
1256     LOG(ERROR) << "RenderPagesForPrint failed";
1257     DidFinishPrinting(FAIL_PRINT);
1258   }
1259   ResetScriptedPrintCount();
1260 }
1261
1262 void PrintWebViewHelper::DidFinishPrinting(PrintingResult result) {
1263   switch (result) {
1264     case OK:
1265       break;
1266
1267     case FAIL_PRINT_INIT:
1268       DCHECK(!notify_browser_of_print_failure_);
1269       break;
1270
1271     case FAIL_PRINT:
1272       if (notify_browser_of_print_failure_ && print_pages_params_.get()) {
1273         int cookie = print_pages_params_->params.document_cookie;
1274         Send(new PrintHostMsg_PrintingFailed(routing_id(), cookie));
1275       }
1276       break;
1277
1278     case FAIL_PREVIEW:
1279       DCHECK(is_preview_enabled_);
1280       int cookie = print_pages_params_.get() ?
1281           print_pages_params_->params.document_cookie : 0;
1282       if (notify_browser_of_print_failure_) {
1283         LOG(ERROR) << "CreatePreviewDocument failed";
1284         Send(new PrintHostMsg_PrintPreviewFailed(routing_id(), cookie));
1285       } else {
1286         Send(new PrintHostMsg_PrintPreviewCancelled(routing_id(), cookie));
1287       }
1288       print_preview_context_.Failed(notify_browser_of_print_failure_);
1289       break;
1290   }
1291
1292   prep_frame_view_.reset();
1293   print_pages_params_.reset();
1294   notify_browser_of_print_failure_ = true;
1295 }
1296
1297 void PrintWebViewHelper::OnFramePreparedForPrintPages() {
1298   PrintPages();
1299   FinishFramePrinting();
1300 }
1301
1302 void PrintWebViewHelper::PrintPages() {
1303   if (!prep_frame_view_)  // Printing is already canceled or failed.
1304     return;
1305   prep_frame_view_->StartPrinting();
1306
1307   int page_count = prep_frame_view_->GetExpectedPageCount();
1308   if (!page_count) {
1309     LOG(ERROR) << "Can't print 0 pages.";
1310     return DidFinishPrinting(FAIL_PRINT);
1311   }
1312
1313   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1314   const PrintMsg_Print_Params& print_params = params.params;
1315
1316 #if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
1317   // TODO(vitalybuka): should be page_count or valid pages from params.pages.
1318   // See http://crbug.com/161576
1319   Send(new PrintHostMsg_DidGetPrintedPagesCount(routing_id(),
1320                                                 print_params.document_cookie,
1321                                                 page_count));
1322 #endif  // !defined(OS_CHROMEOS)
1323
1324   if (print_params.preview_ui_id < 0) {
1325     // Printing for system dialog.
1326     int printed_count = params.pages.empty() ? page_count : params.pages.size();
1327 #if !defined(OS_CHROMEOS)
1328     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.SystemDialog", printed_count);
1329 #else
1330     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.PrintToCloudPrintWebDialog",
1331                          printed_count);
1332 #endif  // !defined(OS_CHROMEOS)
1333   }
1334
1335
1336   if (!PrintPagesNative(prep_frame_view_->frame(), page_count,
1337                         prep_frame_view_->GetPrintCanvasSize())) {
1338     LOG(ERROR) << "Printing failed.";
1339     return DidFinishPrinting(FAIL_PRINT);
1340   }
1341 }
1342
1343 void PrintWebViewHelper::FinishFramePrinting() {
1344   prep_frame_view_.reset();
1345 }
1346
1347 #if defined(OS_MACOSX) || defined(OS_WIN)
1348 bool PrintWebViewHelper::PrintPagesNative(blink::WebFrame* frame,
1349                                           int page_count,
1350                                           const gfx::Size& canvas_size) {
1351   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1352   const PrintMsg_Print_Params& print_params = params.params;
1353
1354   PrintMsg_PrintPage_Params page_params;
1355   page_params.params = print_params;
1356   if (params.pages.empty()) {
1357     for (int i = 0; i < page_count; ++i) {
1358       page_params.page_number = i;
1359       PrintPageInternal(page_params, canvas_size, frame);
1360     }
1361   } else {
1362     for (size_t i = 0; i < params.pages.size(); ++i) {
1363       if (params.pages[i] >= page_count)
1364         break;
1365       page_params.page_number = params.pages[i];
1366       PrintPageInternal(page_params, canvas_size, frame);
1367     }
1368   }
1369   return true;
1370 }
1371
1372 #endif  // OS_MACOSX || OS_WIN
1373
1374 // static - Not anonymous so that platform implementations can use it.
1375 void PrintWebViewHelper::ComputePageLayoutInPointsForCss(
1376     blink::WebFrame* frame,
1377     int page_index,
1378     const PrintMsg_Print_Params& page_params,
1379     bool ignore_css_margins,
1380     double* scale_factor,
1381     PageSizeMargins* page_layout_in_points) {
1382   PrintMsg_Print_Params params = CalculatePrintParamsForCss(
1383       frame, page_index, page_params, ignore_css_margins,
1384       page_params.print_scaling_option ==
1385           blink::WebPrintScalingOptionFitToPrintableArea,
1386       scale_factor);
1387   CalculatePageLayoutFromPrintParams(params, page_layout_in_points);
1388 }
1389
1390 bool PrintWebViewHelper::InitPrintSettings(bool fit_to_paper_size) {
1391   PrintMsg_PrintPages_Params settings;
1392   Send(new PrintHostMsg_GetDefaultPrintSettings(routing_id(),
1393                                                 &settings.params));
1394   // Check if the printer returned any settings, if the settings is empty, we
1395   // can safely assume there are no printer drivers configured. So we safely
1396   // terminate.
1397   bool result = true;
1398   if (!PrintMsg_Print_Params_IsValid(settings.params))
1399     result = false;
1400
1401   if (result &&
1402       (settings.params.dpi < kMinDpi || settings.params.document_cookie == 0)) {
1403     // Invalid print page settings.
1404     NOTREACHED();
1405     result = false;
1406   }
1407
1408   // Reset to default values.
1409   ignore_css_margins_ = false;
1410   settings.pages.clear();
1411
1412   settings.params.print_scaling_option =
1413       blink::WebPrintScalingOptionSourceSize;
1414   if (fit_to_paper_size) {
1415     settings.params.print_scaling_option =
1416         blink::WebPrintScalingOptionFitToPrintableArea;
1417   }
1418
1419   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1420   return result;
1421 }
1422
1423 bool PrintWebViewHelper::CalculateNumberOfPages(blink::WebLocalFrame* frame,
1424                                                 const blink::WebNode& node,
1425                                                 int* number_of_pages) {
1426   DCHECK(frame);
1427   bool fit_to_paper_size = !(PrintingNodeOrPdfFrame(frame, node));
1428   if (!InitPrintSettings(fit_to_paper_size)) {
1429     notify_browser_of_print_failure_ = false;
1430 #if !defined(OS_ANDROID)
1431     // TODO(sgurun) android_webview hack
1432     render_view()->RunModalAlertDialog(
1433         frame,
1434         l10n_util::GetStringUTF16(IDS_PRINT_INVALID_PRINTER_SETTINGS));
1435 #endif  //  !defined(OS_ANDROID)
1436     return false;
1437   }
1438
1439   const PrintMsg_Print_Params& params = print_pages_params_->params;
1440   PrepareFrameAndViewForPrint prepare(params, frame, node, ignore_css_margins_);
1441   prepare.StartPrinting();
1442
1443   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
1444                                              params.document_cookie));
1445   *number_of_pages = prepare.GetExpectedPageCount();
1446   return true;
1447 }
1448
1449 bool PrintWebViewHelper::UpdatePrintSettings(
1450     blink::WebLocalFrame* frame,
1451     const blink::WebNode& node,
1452     const base::DictionaryValue& passed_job_settings) {
1453   DCHECK(is_preview_enabled_);
1454   const base::DictionaryValue* job_settings = &passed_job_settings;
1455   base::DictionaryValue modified_job_settings;
1456   if (job_settings->empty()) {
1457     if (!print_for_preview_)
1458       print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1459     return false;
1460   }
1461
1462   bool source_is_html = true;
1463   if (print_for_preview_) {
1464     if (!job_settings->GetBoolean(kSettingPreviewModifiable, &source_is_html)) {
1465       NOTREACHED();
1466     }
1467   } else {
1468     source_is_html = !PrintingNodeOrPdfFrame(frame, node);
1469   }
1470
1471   if (print_for_preview_ || !source_is_html) {
1472     modified_job_settings.MergeDictionary(job_settings);
1473     modified_job_settings.SetBoolean(kSettingHeaderFooterEnabled, false);
1474     modified_job_settings.SetInteger(kSettingMarginsType, NO_MARGINS);
1475     job_settings = &modified_job_settings;
1476   }
1477
1478   // Send the cookie so that UpdatePrintSettings can reuse PrinterQuery when
1479   // possible.
1480   int cookie = print_pages_params_.get() ?
1481       print_pages_params_->params.document_cookie : 0;
1482   PrintMsg_PrintPages_Params settings;
1483   Send(new PrintHostMsg_UpdatePrintSettings(routing_id(), cookie, *job_settings,
1484                                             &settings));
1485   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1486
1487   if (!PrintMsg_Print_Params_IsValid(settings.params)) {
1488     if (!print_for_preview_) {
1489       print_preview_context_.set_error(PREVIEW_ERROR_INVALID_PRINTER_SETTINGS);
1490     } else {
1491 #if !defined(OS_ANDROID)
1492       // TODO(sgurun) android_webview hack
1493       // PrintForPrintPreview
1494       blink::WebFrame* print_frame = NULL;
1495       // This may not be the right frame, but the alert will be modal,
1496       // therefore it works well enough.
1497       GetPrintFrame(&print_frame);
1498       if (print_frame) {
1499         render_view()->RunModalAlertDialog(
1500             print_frame,
1501             l10n_util::GetStringUTF16(
1502                 IDS_PRINT_INVALID_PRINTER_SETTINGS));
1503       }
1504 #endif  // !defined(OS_ANDROID)
1505     }
1506     return false;
1507   }
1508
1509   if (settings.params.dpi < kMinDpi || !settings.params.document_cookie) {
1510     print_preview_context_.set_error(PREVIEW_ERROR_UPDATING_PRINT_SETTINGS);
1511     return false;
1512   }
1513
1514   if (!job_settings->GetInteger(kPreviewUIID, &settings.params.preview_ui_id)) {
1515     NOTREACHED();
1516     print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1517     return false;
1518   }
1519
1520   if (!print_for_preview_) {
1521     // Validate expected print preview settings.
1522     if (!job_settings->GetInteger(kPreviewRequestID,
1523                                   &settings.params.preview_request_id) ||
1524         !job_settings->GetBoolean(kIsFirstRequest,
1525                                   &settings.params.is_first_request)) {
1526       NOTREACHED();
1527       print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1528       return false;
1529     }
1530
1531     settings.params.print_to_pdf = IsPrintToPdfRequested(*job_settings);
1532     UpdateFrameMarginsCssInfo(*job_settings);
1533     settings.params.print_scaling_option = GetPrintScalingOption(
1534         source_is_html, *job_settings, settings.params);
1535
1536     // Header/Footer: Set |header_footer_info_|.
1537     if (settings.params.display_header_footer) {
1538       header_footer_info_.reset(new base::DictionaryValue());
1539       header_footer_info_->SetDouble(kSettingHeaderFooterDate,
1540                                      base::Time::Now().ToJsTime());
1541       header_footer_info_->SetString(kSettingHeaderFooterURL,
1542                                      settings.params.url);
1543       header_footer_info_->SetString(kSettingHeaderFooterTitle,
1544                                      settings.params.title);
1545     }
1546   }
1547
1548   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1549   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
1550                                              settings.params.document_cookie));
1551
1552   return true;
1553 }
1554
1555 bool PrintWebViewHelper::GetPrintSettingsFromUser(blink::WebFrame* frame,
1556                                                   const blink::WebNode& node,
1557                                                   int expected_pages_count) {
1558   PrintHostMsg_ScriptedPrint_Params params;
1559   PrintMsg_PrintPages_Params print_settings;
1560
1561   params.cookie = print_pages_params_->params.document_cookie;
1562   params.has_selection = frame->hasSelection();
1563   params.expected_pages_count = expected_pages_count;
1564   MarginType margin_type = DEFAULT_MARGINS;
1565   if (PrintingNodeOrPdfFrame(frame, node))
1566     margin_type = GetMarginsForPdf(frame, node);
1567   params.margin_type = margin_type;
1568
1569   Send(new PrintHostMsg_DidShowPrintDialog(routing_id()));
1570
1571   // PrintHostMsg_ScriptedPrint will reset print_scaling_option, so we save the
1572   // value before and restore it afterwards.
1573   blink::WebPrintScalingOption scaling_option =
1574       print_pages_params_->params.print_scaling_option;
1575
1576   print_pages_params_.reset();
1577   IPC::SyncMessage* msg =
1578       new PrintHostMsg_ScriptedPrint(routing_id(), params, &print_settings);
1579   msg->EnableMessagePumping();
1580   Send(msg);
1581   print_pages_params_.reset(new PrintMsg_PrintPages_Params(print_settings));
1582
1583   print_pages_params_->params.print_scaling_option = scaling_option;
1584   return (print_settings.params.dpi && print_settings.params.document_cookie);
1585 }
1586
1587 bool PrintWebViewHelper::RenderPagesForPrint(blink::WebLocalFrame* frame,
1588                                              const blink::WebNode& node) {
1589   if (!frame || prep_frame_view_)
1590     return false;
1591   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1592   const PrintMsg_Print_Params& print_params = params.params;
1593   prep_frame_view_.reset(new PrepareFrameAndViewForPrint(
1594       print_params, frame, node, ignore_css_margins_));
1595   DCHECK(!print_pages_params_->params.selection_only ||
1596          print_pages_params_->pages.empty());
1597   prep_frame_view_->CopySelectionIfNeeded(
1598       render_view()->GetWebkitPreferences(),
1599       base::Bind(&PrintWebViewHelper::OnFramePreparedForPrintPages,
1600                  base::Unretained(this)));
1601   return true;
1602 }
1603
1604 #if defined(OS_POSIX)
1605 bool PrintWebViewHelper::CopyMetafileDataToSharedMem(
1606     Metafile* metafile,
1607     base::SharedMemoryHandle* shared_mem_handle) {
1608   uint32 buf_size = metafile->GetDataSize();
1609   scoped_ptr<base::SharedMemory> shared_buf(
1610       content::RenderThread::Get()->HostAllocateSharedMemoryBuffer(
1611           buf_size).release());
1612
1613   if (shared_buf.get()) {
1614     if (shared_buf->Map(buf_size)) {
1615       metafile->GetData(shared_buf->memory(), buf_size);
1616       shared_buf->GiveToProcess(base::GetCurrentProcessHandle(),
1617                                 shared_mem_handle);
1618       return true;
1619     }
1620   }
1621   NOTREACHED();
1622   return false;
1623 }
1624 #endif  // defined(OS_POSIX)
1625
1626 bool PrintWebViewHelper::IsScriptInitiatedPrintTooFrequent(
1627     blink::WebFrame* frame) {
1628   const int kMinSecondsToIgnoreJavascriptInitiatedPrint = 2;
1629   const int kMaxSecondsToIgnoreJavascriptInitiatedPrint = 32;
1630   bool too_frequent = false;
1631
1632   // Check if there is script repeatedly trying to print and ignore it if too
1633   // frequent.  The first 3 times, we use a constant wait time, but if this
1634   // gets excessive, we switch to exponential wait time. So for a page that
1635   // calls print() in a loop the user will need to cancel the print dialog
1636   // after: [2, 2, 2, 4, 8, 16, 32, 32, ...] seconds.
1637   // This gives the user time to navigate from the page.
1638   if (user_cancelled_scripted_print_count_ > 0) {
1639     base::TimeDelta diff = base::Time::Now() - last_cancelled_script_print_;
1640     int min_wait_seconds = kMinSecondsToIgnoreJavascriptInitiatedPrint;
1641     if (user_cancelled_scripted_print_count_ > 3) {
1642       min_wait_seconds = std::min(
1643           kMinSecondsToIgnoreJavascriptInitiatedPrint <<
1644               (user_cancelled_scripted_print_count_ - 3),
1645           kMaxSecondsToIgnoreJavascriptInitiatedPrint);
1646     }
1647     if (diff.InSeconds() < min_wait_seconds) {
1648       too_frequent = true;
1649     }
1650   }
1651
1652   if (!too_frequent)
1653     return false;
1654
1655   blink::WebString message(
1656       blink::WebString::fromUTF8("Ignoring too frequent calls to print()."));
1657   frame->addMessageToConsole(
1658       blink::WebConsoleMessage(
1659           blink::WebConsoleMessage::LevelWarning, message));
1660   return true;
1661 }
1662
1663 void PrintWebViewHelper::ResetScriptedPrintCount() {
1664   // Reset cancel counter on successful print.
1665   user_cancelled_scripted_print_count_ = 0;
1666 }
1667
1668 void PrintWebViewHelper::IncrementScriptedPrintCount() {
1669   ++user_cancelled_scripted_print_count_;
1670   last_cancelled_script_print_ = base::Time::Now();
1671 }
1672
1673 void PrintWebViewHelper::ShowScriptedPrintPreview() {
1674   if (is_scripted_preview_delayed_) {
1675     is_scripted_preview_delayed_ = false;
1676     Send(new PrintHostMsg_ShowScriptedPrintPreview(routing_id(),
1677             print_preview_context_.IsModifiable()));
1678   }
1679 }
1680
1681 void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
1682   const bool is_modifiable = print_preview_context_.IsModifiable();
1683   const bool has_selection = print_preview_context_.HasSelection();
1684   PrintHostMsg_RequestPrintPreview_Params params;
1685   params.is_modifiable = is_modifiable;
1686   params.has_selection = has_selection;
1687   switch (type) {
1688     case PRINT_PREVIEW_SCRIPTED: {
1689       // Shows scripted print preview in two stages.
1690       // 1. PrintHostMsg_SetupScriptedPrintPreview blocks this call and JS by
1691       //    pumping messages here.
1692       // 2. PrintHostMsg_ShowScriptedPrintPreview shows preview once the
1693       //    document has been loaded.
1694       is_scripted_preview_delayed_ = true;
1695       if (is_loading_ && GetPlugin(print_preview_context_.source_frame())) {
1696         // Wait for DidStopLoading. Plugins may not know the correct
1697         // |is_modifiable| value until they are fully loaded, which occurs when
1698         // DidStopLoading() is called. Defer showing the preview until then.
1699       } else {
1700         base::MessageLoop::current()->PostTask(
1701             FROM_HERE,
1702             base::Bind(&PrintWebViewHelper::ShowScriptedPrintPreview,
1703                        weak_ptr_factory_.GetWeakPtr()));
1704       }
1705       IPC::SyncMessage* msg =
1706           new PrintHostMsg_SetupScriptedPrintPreview(routing_id());
1707       msg->EnableMessagePumping();
1708       Send(msg);
1709       is_scripted_preview_delayed_ = false;
1710       return;
1711     }
1712     case PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME: {
1713       break;
1714     }
1715     case PRINT_PREVIEW_USER_INITIATED_SELECTION: {
1716       DCHECK(has_selection);
1717       params.selection_only = has_selection;
1718       break;
1719     }
1720     case PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE: {
1721       params.webnode_only = true;
1722       break;
1723     }
1724     default: {
1725       NOTREACHED();
1726       return;
1727     }
1728   }
1729   Send(new PrintHostMsg_RequestPrintPreview(routing_id(), params));
1730 }
1731
1732 bool PrintWebViewHelper::CheckForCancel() {
1733   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1734   bool cancel = false;
1735   Send(new PrintHostMsg_CheckForCancel(routing_id(),
1736                                        print_params.preview_ui_id,
1737                                        print_params.preview_request_id,
1738                                        &cancel));
1739   if (cancel)
1740     notify_browser_of_print_failure_ = false;
1741   return cancel;
1742 }
1743
1744 bool PrintWebViewHelper::PreviewPageRendered(int page_number,
1745                                              Metafile* metafile) {
1746   DCHECK_GE(page_number, FIRST_PAGE_INDEX);
1747
1748   // For non-modifiable files, |metafile| should be NULL, so do not bother
1749   // sending a message. If we don't generate draft metafiles, |metafile| is
1750   // NULL.
1751   if (!print_preview_context_.IsModifiable() ||
1752       !print_preview_context_.generate_draft_pages()) {
1753     DCHECK(!metafile);
1754     return true;
1755   }
1756
1757   if (!metafile) {
1758     NOTREACHED();
1759     print_preview_context_.set_error(
1760         PREVIEW_ERROR_PAGE_RENDERED_WITHOUT_METAFILE);
1761     return false;
1762   }
1763
1764   PrintHostMsg_DidPreviewPage_Params preview_page_params;
1765   // Get the size of the resulting metafile.
1766   uint32 buf_size = metafile->GetDataSize();
1767   DCHECK_GT(buf_size, 0u);
1768   if (!CopyMetafileDataToSharedMem(
1769       metafile, &(preview_page_params.metafile_data_handle))) {
1770     LOG(ERROR) << "CopyMetafileDataToSharedMem failed";
1771     print_preview_context_.set_error(PREVIEW_ERROR_METAFILE_COPY_FAILED);
1772     return false;
1773   }
1774   preview_page_params.data_size = buf_size;
1775   preview_page_params.page_number = page_number;
1776   preview_page_params.preview_request_id =
1777       print_pages_params_->params.preview_request_id;
1778
1779   Send(new PrintHostMsg_DidPreviewPage(routing_id(), preview_page_params));
1780   return true;
1781 }
1782
1783 PrintWebViewHelper::PrintPreviewContext::PrintPreviewContext()
1784     : total_page_count_(0),
1785       current_page_index_(0),
1786       generate_draft_pages_(true),
1787       print_ready_metafile_page_count_(0),
1788       error_(PREVIEW_ERROR_NONE),
1789       state_(UNINITIALIZED) {
1790 }
1791
1792 PrintWebViewHelper::PrintPreviewContext::~PrintPreviewContext() {
1793 }
1794
1795 void PrintWebViewHelper::PrintPreviewContext::InitWithFrame(
1796     blink::WebLocalFrame* web_frame) {
1797   DCHECK(web_frame);
1798   DCHECK(!IsRendering());
1799   state_ = INITIALIZED;
1800   source_frame_.Reset(web_frame);
1801   source_node_.reset();
1802 }
1803
1804 void PrintWebViewHelper::PrintPreviewContext::InitWithNode(
1805     const blink::WebNode& web_node) {
1806   DCHECK(!web_node.isNull());
1807   DCHECK(web_node.document().frame());
1808   DCHECK(!IsRendering());
1809   state_ = INITIALIZED;
1810   source_frame_.Reset(web_node.document().frame());
1811   source_node_ = web_node;
1812 }
1813
1814 void PrintWebViewHelper::PrintPreviewContext::OnPrintPreview() {
1815   DCHECK_EQ(INITIALIZED, state_);
1816   ClearContext();
1817 }
1818
1819 bool PrintWebViewHelper::PrintPreviewContext::CreatePreviewDocument(
1820     PrepareFrameAndViewForPrint* prepared_frame,
1821     const std::vector<int>& pages) {
1822   DCHECK_EQ(INITIALIZED, state_);
1823   state_ = RENDERING;
1824
1825   // Need to make sure old object gets destroyed first.
1826   prep_frame_view_.reset(prepared_frame);
1827   prep_frame_view_->StartPrinting();
1828
1829   total_page_count_ = prep_frame_view_->GetExpectedPageCount();
1830   if (total_page_count_ == 0) {
1831     LOG(ERROR) << "CreatePreviewDocument got 0 page count";
1832     set_error(PREVIEW_ERROR_ZERO_PAGES);
1833     return false;
1834   }
1835
1836   metafile_.reset(new PreviewMetafile);
1837   if (!metafile_->Init()) {
1838     set_error(PREVIEW_ERROR_METAFILE_INIT_FAILED);
1839     LOG(ERROR) << "PreviewMetafile Init failed";
1840     return false;
1841   }
1842
1843   current_page_index_ = 0;
1844   pages_to_render_ = pages;
1845   // Sort and make unique.
1846   std::sort(pages_to_render_.begin(), pages_to_render_.end());
1847   pages_to_render_.resize(std::unique(pages_to_render_.begin(),
1848                                       pages_to_render_.end()) -
1849                           pages_to_render_.begin());
1850   // Remove invalid pages.
1851   pages_to_render_.resize(std::lower_bound(pages_to_render_.begin(),
1852                                            pages_to_render_.end(),
1853                                            total_page_count_) -
1854                           pages_to_render_.begin());
1855   print_ready_metafile_page_count_ = pages_to_render_.size();
1856   if (pages_to_render_.empty()) {
1857     print_ready_metafile_page_count_ = total_page_count_;
1858     // Render all pages.
1859     for (int i = 0; i < total_page_count_; ++i)
1860       pages_to_render_.push_back(i);
1861   } else if (generate_draft_pages_) {
1862     int pages_index = 0;
1863     for (int i = 0; i < total_page_count_; ++i) {
1864       if (pages_index < print_ready_metafile_page_count_ &&
1865           i == pages_to_render_[pages_index]) {
1866         pages_index++;
1867         continue;
1868       }
1869       pages_to_render_.push_back(i);
1870     }
1871   }
1872
1873   document_render_time_ = base::TimeDelta();
1874   begin_time_ = base::TimeTicks::Now();
1875
1876   return true;
1877 }
1878
1879 void PrintWebViewHelper::PrintPreviewContext::RenderedPreviewPage(
1880     const base::TimeDelta& page_time) {
1881   DCHECK_EQ(RENDERING, state_);
1882   document_render_time_ += page_time;
1883   UMA_HISTOGRAM_TIMES("PrintPreview.RenderPDFPageTime", page_time);
1884 }
1885
1886 void PrintWebViewHelper::PrintPreviewContext::AllPagesRendered() {
1887   DCHECK_EQ(RENDERING, state_);
1888   state_ = DONE;
1889   prep_frame_view_->FinishPrinting();
1890 }
1891
1892 void PrintWebViewHelper::PrintPreviewContext::FinalizePrintReadyDocument() {
1893   DCHECK(IsRendering());
1894
1895   base::TimeTicks begin_time = base::TimeTicks::Now();
1896   metafile_->FinishDocument();
1897
1898   if (print_ready_metafile_page_count_ <= 0) {
1899     NOTREACHED();
1900     return;
1901   }
1902
1903   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderToPDFTime",
1904                              document_render_time_);
1905   base::TimeDelta total_time = (base::TimeTicks::Now() - begin_time) +
1906                                document_render_time_;
1907   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderAndGeneratePDFTime",
1908                              total_time);
1909   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderAndGeneratePDFTimeAvgPerPage",
1910                              total_time / pages_to_render_.size());
1911 }
1912
1913 void PrintWebViewHelper::PrintPreviewContext::Finished() {
1914   DCHECK_EQ(DONE, state_);
1915   state_ = INITIALIZED;
1916   ClearContext();
1917 }
1918
1919 void PrintWebViewHelper::PrintPreviewContext::Failed(bool report_error) {
1920   DCHECK(state_ == INITIALIZED || state_ == RENDERING);
1921   state_ = INITIALIZED;
1922   if (report_error) {
1923     DCHECK_NE(PREVIEW_ERROR_NONE, error_);
1924     UMA_HISTOGRAM_ENUMERATION("PrintPreview.RendererError", error_,
1925                               PREVIEW_ERROR_LAST_ENUM);
1926   }
1927   ClearContext();
1928 }
1929
1930 int PrintWebViewHelper::PrintPreviewContext::GetNextPageNumber() {
1931   DCHECK_EQ(RENDERING, state_);
1932   if (IsFinalPageRendered())
1933     return -1;
1934   return pages_to_render_[current_page_index_++];
1935 }
1936
1937 bool PrintWebViewHelper::PrintPreviewContext::IsRendering() const {
1938   return state_ == RENDERING || state_ == DONE;
1939 }
1940
1941 bool PrintWebViewHelper::PrintPreviewContext::IsModifiable() {
1942   // The only kind of node we can print right now is a PDF node.
1943   return !PrintingNodeOrPdfFrame(source_frame(), source_node_);
1944 }
1945
1946 bool PrintWebViewHelper::PrintPreviewContext::HasSelection() {
1947   return IsModifiable() && source_frame()->hasSelection();
1948 }
1949
1950 bool PrintWebViewHelper::PrintPreviewContext::IsLastPageOfPrintReadyMetafile()
1951     const {
1952   DCHECK(IsRendering());
1953   return current_page_index_ == print_ready_metafile_page_count_;
1954 }
1955
1956 bool  PrintWebViewHelper::PrintPreviewContext::IsFinalPageRendered() const {
1957   DCHECK(IsRendering());
1958   return static_cast<size_t>(current_page_index_) == pages_to_render_.size();
1959 }
1960
1961 void PrintWebViewHelper::PrintPreviewContext::set_generate_draft_pages(
1962     bool generate_draft_pages) {
1963   DCHECK_EQ(INITIALIZED, state_);
1964   generate_draft_pages_ = generate_draft_pages;
1965 }
1966
1967 void PrintWebViewHelper::PrintPreviewContext::set_error(
1968     enum PrintPreviewErrorBuckets error) {
1969   error_ = error;
1970 }
1971
1972 blink::WebLocalFrame* PrintWebViewHelper::PrintPreviewContext::source_frame() {
1973   DCHECK(state_ != UNINITIALIZED);
1974   return source_frame_.GetFrame();
1975 }
1976
1977 const blink::WebNode&
1978     PrintWebViewHelper::PrintPreviewContext::source_node() const {
1979   DCHECK(state_ != UNINITIALIZED);
1980   return source_node_;
1981 }
1982
1983 blink::WebLocalFrame*
1984 PrintWebViewHelper::PrintPreviewContext::prepared_frame() {
1985   DCHECK(state_ != UNINITIALIZED);
1986   return prep_frame_view_->frame();
1987 }
1988
1989 const blink::WebNode&
1990     PrintWebViewHelper::PrintPreviewContext::prepared_node() const {
1991   DCHECK(state_ != UNINITIALIZED);
1992   return prep_frame_view_->node();
1993 }
1994
1995 int PrintWebViewHelper::PrintPreviewContext::total_page_count() const {
1996   DCHECK(state_ != UNINITIALIZED);
1997   return total_page_count_;
1998 }
1999
2000 bool PrintWebViewHelper::PrintPreviewContext::generate_draft_pages() const {
2001   return generate_draft_pages_;
2002 }
2003
2004 PreviewMetafile* PrintWebViewHelper::PrintPreviewContext::metafile() {
2005   DCHECK(IsRendering());
2006   return metafile_.get();
2007 }
2008
2009 int PrintWebViewHelper::PrintPreviewContext::last_error() const {
2010   return error_;
2011 }
2012
2013 gfx::Size PrintWebViewHelper::PrintPreviewContext::GetPrintCanvasSize() const {
2014   DCHECK(IsRendering());
2015   return prep_frame_view_->GetPrintCanvasSize();
2016 }
2017
2018 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
2019   prep_frame_view_.reset();
2020   metafile_.reset();
2021   pages_to_render_.clear();
2022   error_ = PREVIEW_ERROR_NONE;
2023 }
2024
2025 }  // namespace printing