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/pdf_metafile_skia.h"
  27 #include "printing/units.h"
  28 #include "third_party/WebKit/public/platform/WebSize.h"
  29 #include "third_party/WebKit/public/platform/WebURLRequest.h"
  30 #include "third_party/WebKit/public/web/WebConsoleMessage.h"
  31 #include "third_party/WebKit/public/web/WebDocument.h"
  32 #include "third_party/WebKit/public/web/WebElement.h"
  33 #include "third_party/WebKit/public/web/WebFrameClient.h"
  34 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  35 #include "third_party/WebKit/public/web/WebPlugin.h"
  36 #include "third_party/WebKit/public/web/WebPluginDocument.h"
  37 #include "third_party/WebKit/public/web/WebPrintParams.h"
  38 #include "third_party/WebKit/public/web/WebPrintScalingOption.h"
  39 #include "third_party/WebKit/public/web/WebSandboxFlags.h"
  40 #include "third_party/WebKit/public/web/WebScriptSource.h"
  41 #include "third_party/WebKit/public/web/WebSettings.h"
  42 #include "third_party/WebKit/public/web/WebView.h"
  43 #include "third_party/WebKit/public/web/WebViewClient.h"
  44 #include "ui/base/l10n/l10n_util.h"
  45 #include "ui/base/resource/resource_bundle.h"
  46
  47 // This code is copied from chrome/renderer/printing. Code is slightly
  48 // modified to run it with webview, and the modifications are marked
  49 // using OS_ANDROID.
  50 // TODO(sgurun): remove the code as part of componentization of printing.
  51
  52 using content::WebPreferences;
  53
  54 namespace printing {
  55
  56 namespace {
  57
  58 enum PrintPreviewHelperEvents {
  59   PREVIEW_EVENT_REQUESTED,
  60   PREVIEW_EVENT_CACHE_HIT,  // Unused
  61   PREVIEW_EVENT_CREATE_DOCUMENT,
  62   PREVIEW_EVENT_NEW_SETTINGS,  // Unused
  63   PREVIEW_EVENT_MAX,
  64 };
  65
  66 const double kMinDpi = 1.0;
  67
  68 #if 0
  69 // TODO(sgurun) android_webview hack
  70 const char kPageLoadScriptFormat[] =
  71     "document.open(); document.write(%s); document.close();";
  72
  73 const char kPageSetupScriptFormat[] = "setup(%s);";
  74
  75 void ExecuteScript(blink::WebFrame* frame,
  76                    const char* script_format,
  77                    const base::Value& parameters) {
  78   std::string json;
  79   base::JSONWriter::Write(&parameters, &json);
  80   std::string script = base::StringPrintf(script_format, json.c_str());
  81   frame->executeScript(blink::WebString(base::UTF8ToUTF16(script)));
  82 }
  83 #endif
  84
  85 int GetDPI(const PrintMsg_Print_Params* print_params) {
  86 #if defined(OS_MACOSX)
  87   // On the Mac, the printable area is in points, don't do any scaling based
  88   // on dpi.
  89   return kPointsPerInch;
  90 #else
  91   return static_cast<int>(print_params->dpi);
  92 #endif  // defined(OS_MACOSX)
  93 }
  94
  95 bool PrintMsg_Print_Params_IsValid(const PrintMsg_Print_Params& params) {
  96   return !params.content_size.IsEmpty() && !params.page_size.IsEmpty() &&
  97          !params.printable_area.IsEmpty() && params.document_cookie &&
  98          params.desired_dpi && params.max_shrink && params.min_shrink &&
  99          params.dpi && (params.margin_top >= 0) && (params.margin_left >= 0);
 100 }
 101
 102 PrintMsg_Print_Params GetCssPrintParams(
 103     blink::WebFrame* frame,
 104     int page_index,
 105     const PrintMsg_Print_Params& page_params) {
 106   PrintMsg_Print_Params page_css_params = page_params;
 107   int dpi = GetDPI(&page_params);
 108
 109   blink::WebSize page_size_in_pixels(
 110       ConvertUnit(page_params.page_size.width(), dpi, kPixelsPerInch),
 111       ConvertUnit(page_params.page_size.height(), dpi, kPixelsPerInch));
 112   int margin_top_in_pixels =
 113       ConvertUnit(page_params.margin_top, dpi, kPixelsPerInch);
 114   int margin_right_in_pixels = ConvertUnit(
 115       page_params.page_size.width() -
 116       page_params.content_size.width() - page_params.margin_left,
 117       dpi, kPixelsPerInch);
 118   int margin_bottom_in_pixels = ConvertUnit(
 119       page_params.page_size.height() -
 120       page_params.content_size.height() - page_params.margin_top,
 121       dpi, kPixelsPerInch);
 122   int margin_left_in_pixels = ConvertUnit(
 123       page_params.margin_left,
 124       dpi, kPixelsPerInch);
 125
 126   blink::WebSize original_page_size_in_pixels = page_size_in_pixels;
 127
 128   if (frame) {
 129     frame->pageSizeAndMarginsInPixels(page_index,
 130                                       page_size_in_pixels,
 131                                       margin_top_in_pixels,
 132                                       margin_right_in_pixels,
 133                                       margin_bottom_in_pixels,
 134                                       margin_left_in_pixels);
 135   }
 136
 137   int new_content_width = page_size_in_pixels.width -
 138                           margin_left_in_pixels - margin_right_in_pixels;
 139   int new_content_height = page_size_in_pixels.height -
 140                            margin_top_in_pixels - margin_bottom_in_pixels;
 141
 142   // Invalid page size and/or margins. We just use the default setting.
 143   if (new_content_width < 1 || new_content_height < 1) {
 144     CHECK(frame);
 145     page_css_params = GetCssPrintParams(NULL, page_index, page_params);
 146     return page_css_params;
 147   }
 148
 149   page_css_params.content_size = gfx::Size(
 150       ConvertUnit(new_content_width, kPixelsPerInch, dpi),
 151       ConvertUnit(new_content_height, kPixelsPerInch, dpi));
 152
 153   if (original_page_size_in_pixels != page_size_in_pixels) {
 154     page_css_params.page_size = gfx::Size(
 155         ConvertUnit(page_size_in_pixels.width, kPixelsPerInch, dpi),
 156         ConvertUnit(page_size_in_pixels.height, kPixelsPerInch, dpi));
 157   } else {
 158     // Printing frame doesn't have any page size css. Pixels to dpi conversion
 159     // causes rounding off errors. Therefore use the default page size values
 160     // directly.
 161     page_css_params.page_size = page_params.page_size;
 162   }
 163
 164   page_css_params.margin_top =
 165       ConvertUnit(margin_top_in_pixels, kPixelsPerInch, dpi);
 166   page_css_params.margin_left =
 167       ConvertUnit(margin_left_in_pixels, kPixelsPerInch, dpi);
 168   return page_css_params;
 169 }
 170
 171 double FitPrintParamsToPage(const PrintMsg_Print_Params& page_params,
 172                             PrintMsg_Print_Params* params_to_fit) {
 173   double content_width =
 174       static_cast<double>(params_to_fit->content_size.width());
 175   double content_height =
 176       static_cast<double>(params_to_fit->content_size.height());
 177   int default_page_size_height = page_params.page_size.height();
 178   int default_page_size_width = page_params.page_size.width();
 179   int css_page_size_height = params_to_fit->page_size.height();
 180   int css_page_size_width = params_to_fit->page_size.width();
 181
 182   double scale_factor = 1.0f;
 183   if (page_params.page_size == params_to_fit->page_size)
 184     return scale_factor;
 185
 186   if (default_page_size_width < css_page_size_width ||
 187       default_page_size_height < css_page_size_height) {
 188     double ratio_width =
 189         static_cast<double>(default_page_size_width) / css_page_size_width;
 190     double ratio_height =
 191         static_cast<double>(default_page_size_height) / css_page_size_height;
 192     scale_factor = ratio_width < ratio_height ? ratio_width : ratio_height;
 193     content_width *= scale_factor;
 194     content_height *= scale_factor;
 195   }
 196   params_to_fit->margin_top = static_cast<int>(
 197       (default_page_size_height - css_page_size_height * scale_factor) / 2 +
 198       (params_to_fit->margin_top * scale_factor));
 199   params_to_fit->margin_left = static_cast<int>(
 200       (default_page_size_width - css_page_size_width * scale_factor) / 2 +
 201       (params_to_fit->margin_left * scale_factor));
 202   params_to_fit->content_size = gfx::Size(
 203       static_cast<int>(content_width), static_cast<int>(content_height));
 204   params_to_fit->page_size = page_params.page_size;
 205   return scale_factor;
 206 }
 207
 208 void CalculatePageLayoutFromPrintParams(
 209     const PrintMsg_Print_Params& params,
 210     PageSizeMargins* page_layout_in_points) {
 211   int dpi = GetDPI(&params);
 212   int content_width = params.content_size.width();
 213   int content_height = params.content_size.height();
 214
 215   int margin_bottom = params.page_size.height() -
 216                       content_height - params.margin_top;
 217   int margin_right = params.page_size.width() -
 218                       content_width - params.margin_left;
 219
 220   page_layout_in_points->content_width =
 221       ConvertUnit(content_width, dpi, kPointsPerInch);
 222   page_layout_in_points->content_height =
 223       ConvertUnit(content_height, dpi, kPointsPerInch);
 224   page_layout_in_points->margin_top =
 225       ConvertUnit(params.margin_top, dpi, kPointsPerInch);
 226   page_layout_in_points->margin_right =
 227       ConvertUnit(margin_right, dpi, kPointsPerInch);
 228   page_layout_in_points->margin_bottom =
 229       ConvertUnit(margin_bottom, dpi, kPointsPerInch);
 230   page_layout_in_points->margin_left =
 231       ConvertUnit(params.margin_left, dpi, kPointsPerInch);
 232 }
 233
 234 void EnsureOrientationMatches(const PrintMsg_Print_Params& css_params,
 235                               PrintMsg_Print_Params* page_params) {
 236   if ((page_params->page_size.width() > page_params->page_size.height()) ==
 237       (css_params.page_size.width() > css_params.page_size.height())) {
 238     return;
 239   }
 240
 241   // Swap the |width| and |height| values.
 242   page_params->page_size.SetSize(page_params->page_size.height(),
 243                                  page_params->page_size.width());
 244   page_params->content_size.SetSize(page_params->content_size.height(),
 245                                     page_params->content_size.width());
 246   page_params->printable_area.set_size(
 247       gfx::Size(page_params->printable_area.height(),
 248                 page_params->printable_area.width()));
 249 }
 250
 251 void ComputeWebKitPrintParamsInDesiredDpi(
 252     const PrintMsg_Print_Params& print_params,
 253     blink::WebPrintParams* webkit_print_params) {
 254   int dpi = GetDPI(&print_params);
 255   webkit_print_params->printerDPI = dpi;
 256   webkit_print_params->printScalingOption = print_params.print_scaling_option;
 257
 258   webkit_print_params->printContentArea.width =
 259       ConvertUnit(print_params.content_size.width(), dpi,
 260                   print_params.desired_dpi);
 261   webkit_print_params->printContentArea.height =
 262       ConvertUnit(print_params.content_size.height(), dpi,
 263                   print_params.desired_dpi);
 264
 265   webkit_print_params->printableArea.x =
 266       ConvertUnit(print_params.printable_area.x(), dpi,
 267                   print_params.desired_dpi);
 268   webkit_print_params->printableArea.y =
 269       ConvertUnit(print_params.printable_area.y(), dpi,
 270                   print_params.desired_dpi);
 271   webkit_print_params->printableArea.width =
 272       ConvertUnit(print_params.printable_area.width(), dpi,
 273                   print_params.desired_dpi);
 274   webkit_print_params->printableArea.height =
 275       ConvertUnit(print_params.printable_area.height(),
 276                   dpi, print_params.desired_dpi);
 277
 278   webkit_print_params->paperSize.width =
 279       ConvertUnit(print_params.page_size.width(), dpi,
 280                   print_params.desired_dpi);
 281   webkit_print_params->paperSize.height =
 282       ConvertUnit(print_params.page_size.height(), dpi,
 283                   print_params.desired_dpi);
 284 }
 285
 286 blink::WebPlugin* GetPlugin(const blink::WebFrame* frame) {
 287   return frame->document().isPluginDocument() ?
 288          frame->document().to<blink::WebPluginDocument>().plugin() : NULL;
 289 }
 290
 291 bool PrintingNodeOrPdfFrame(const blink::WebFrame* frame,
 292                             const blink::WebNode& node) {
 293   if (!node.isNull())
 294     return true;
 295   blink::WebPlugin* plugin = GetPlugin(frame);
 296   return plugin && plugin->supportsPaginatedPrint();
 297 }
 298
 299 bool PrintingFrameHasPageSizeStyle(blink::WebFrame* frame,
 300                                    int total_page_count) {
 301   if (!frame)
 302     return false;
 303   bool frame_has_custom_page_size_style = false;
 304   for (int i = 0; i < total_page_count; ++i) {
 305     if (frame->hasCustomPageSizeStyle(i)) {
 306       frame_has_custom_page_size_style = true;
 307       break;
 308     }
 309   }
 310   return frame_has_custom_page_size_style;
 311 }
 312
 313 MarginType GetMarginsForPdf(blink::WebFrame* frame,
 314                             const blink::WebNode& node) {
 315   if (frame->isPrintScalingDisabledForPlugin(node))
 316     return NO_MARGINS;
 317   else
 318     return PRINTABLE_AREA_MARGINS;
 319 }
 320
 321 bool FitToPageEnabled(const base::DictionaryValue& job_settings) {
 322   bool fit_to_paper_size = false;
 323   if (!job_settings.GetBoolean(kSettingFitToPageEnabled, &fit_to_paper_size)) {
 324     NOTREACHED();
 325   }
 326   return fit_to_paper_size;
 327 }
 328
 329 PrintMsg_Print_Params CalculatePrintParamsForCss(
 330     blink::WebFrame* frame,
 331     int page_index,
 332     const PrintMsg_Print_Params& page_params,
 333     bool ignore_css_margins,
 334     bool fit_to_page,
 335     double* scale_factor) {
 336   PrintMsg_Print_Params css_params = GetCssPrintParams(frame, page_index,
 337                                                        page_params);
 338
 339   PrintMsg_Print_Params params = page_params;
 340   EnsureOrientationMatches(css_params, &params);
 341
 342   if (ignore_css_margins && fit_to_page)
 343     return params;
 344
 345   PrintMsg_Print_Params result_params = css_params;
 346   if (ignore_css_margins) {
 347     result_params.margin_top = params.margin_top;
 348     result_params.margin_left = params.margin_left;
 349
 350     DCHECK(!fit_to_page);
 351     // Since we are ignoring the margins, the css page size is no longer
 352     // valid.
 353     int default_margin_right = params.page_size.width() -
 354         params.content_size.width() - params.margin_left;
 355     int default_margin_bottom = params.page_size.height() -
 356         params.content_size.height() - params.margin_top;
 357     result_params.content_size = gfx::Size(
 358         result_params.page_size.width() - result_params.margin_left -
 359             default_margin_right,
 360         result_params.page_size.height() - result_params.margin_top -
 361             default_margin_bottom);
 362   }
 363
 364   if (fit_to_page) {
 365     double factor = FitPrintParamsToPage(params, &result_params);
 366     if (scale_factor)
 367       *scale_factor = factor;
 368   }
 369   return result_params;
 370 }
 371
 372 bool IsPrintPreviewEnabled() {
 373   return false;
 374 }
 375
 376 bool IsPrintThrottlingDisabled() {
 377   return true;
 378 }
 379
 380 }  // namespace
 381
 382 FrameReference::FrameReference(blink::WebLocalFrame* frame) {
 383   Reset(frame);
 384 }
 385
 386 FrameReference::FrameReference() {
 387   Reset(NULL);
 388 }
 389
 390 FrameReference::~FrameReference() {
 391 }
 392
 393 void FrameReference::Reset(blink::WebLocalFrame* frame) {
 394   if (frame) {
 395     view_ = frame->view();
 396     frame_ = frame;
 397   } else {
 398     view_ = NULL;
 399     frame_ = NULL;
 400   }
 401 }
 402
 403 blink::WebLocalFrame* FrameReference::GetFrame() {
 404   if (view_ == NULL || frame_ == NULL)
 405     return NULL;
 406   for (blink::WebFrame* frame = view_->mainFrame(); frame != NULL;
 407            frame = frame->traverseNext(false)) {
 408     if (frame == frame_)
 409       return frame_;
 410   }
 411   return NULL;
 412 }
 413
 414 blink::WebView* FrameReference::view() {
 415   return view_;
 416 }
 417
 418 // static - Not anonymous so that platform implementations can use it.
 419 void PrintWebViewHelper::PrintHeaderAndFooter(
 420     blink::WebCanvas* canvas,
 421     int page_number,
 422     int total_pages,
 423     float webkit_scale_factor,
 424     const PageSizeMargins& page_layout,
 425     const base::DictionaryValue& header_footer_info,
 426     const PrintMsg_Print_Params& params) {
 427 #if 0
 428   // TODO(sgurun) android_webview hack
 429   SkAutoCanvasRestore auto_restore(canvas, true);
 430   canvas->scale(1 / webkit_scale_factor, 1 / webkit_scale_factor);
 431
 432   blink::WebSize page_size(page_layout.margin_left + page_layout.margin_right +
 433                             page_layout.content_width,
 434                             page_layout.margin_top + page_layout.margin_bottom +
 435                             page_layout.content_height);
 436
 437   blink::WebView* web_view = blink::WebView::create(NULL);
 438   web_view->settings()->setJavaScriptEnabled(true);
 439   blink::WebFrame* frame = blink::WebLocalFrame::create(NULL)
 440   web_view->setMainFrame(web_frame);
 441
 442   base::StringValue html(
 443       ResourceBundle::GetSharedInstance().GetLocalizedString(
 444           IDR_PRINT_PREVIEW_PAGE));
 445   // Load page with script to avoid async operations.
 446   ExecuteScript(frame, kPageLoadScriptFormat, html);
 447
 448   scoped_ptr<base::DictionaryValue> options(header_footer_info.DeepCopy());
 449   options->SetDouble("width", page_size.width);
 450   options->SetDouble("height", page_size.height);
 451   options->SetDouble("topMargin", page_layout.margin_top);
 452   options->SetDouble("bottomMargin", page_layout.margin_bottom);
 453   options->SetString("pageNumber",
 454                      base::StringPrintf("%d/%d", page_number, total_pages));
 455
 456   ExecuteScript(frame, kPageSetupScriptFormat, *options);
 457
 458   blink::WebPrintParams webkit_params(page_size);
 459   webkit_params.printerDPI = GetDPI(&params);
 460
 461   frame->printBegin(webkit_params, WebKit::WebNode(), NULL);
 462   frame->printPage(0, canvas);
 463   frame->printEnd();
 464
 465   web_view->close();
 466   frame->close();
 467 #endif
 468 }
 469
 470 // static - Not anonymous so that platform implementations can use it.
 471 float PrintWebViewHelper::RenderPageContent(blink::WebFrame* frame,
 472                                             int page_number,
 473                                             const gfx::Rect& canvas_area,
 474                                             const gfx::Rect& content_area,
 475                                             double scale_factor,
 476                                             blink::WebCanvas* canvas) {
 477   SkAutoCanvasRestore auto_restore(canvas, true);
 478   if (content_area != canvas_area) {
 479     canvas->translate((content_area.x() - canvas_area.x()) / scale_factor,
 480                       (content_area.y() - canvas_area.y()) / scale_factor);
 481     SkRect clip_rect(
 482         SkRect::MakeXYWH(content_area.origin().x() / scale_factor,
 483                          content_area.origin().y() / scale_factor,
 484                          content_area.size().width() / scale_factor,
 485                          content_area.size().height() / scale_factor));
 486     SkIRect clip_int_rect;
 487     clip_rect.roundOut(&clip_int_rect);
 488     SkRegion clip_region(clip_int_rect);
 489     canvas->setClipRegion(clip_region);
 490   }
 491   return frame->printPage(page_number, canvas);
 492 }
 493
 494 // Class that calls the Begin and End print functions on the frame and changes
 495 // the size of the view temporarily to support full page printing..
 496 class PrepareFrameAndViewForPrint : public blink::WebViewClient,
 497                                     public blink::WebFrameClient {
 498  public:
 499   PrepareFrameAndViewForPrint(const PrintMsg_Print_Params& params,
 500                               blink::WebLocalFrame* frame,
 501                               const blink::WebNode& node,
 502                               bool ignore_css_margins);
 503   virtual ~PrepareFrameAndViewForPrint();
 504
 505   // Optional. Replaces |frame_| with selection if needed. Will call |on_ready|
 506   // when completed.
 507   void CopySelectionIfNeeded(const WebPreferences& preferences,
 508                              const base::Closure& on_ready);
 509
 510   // Prepares frame for printing.
 511   void StartPrinting();
 512
 513   blink::WebLocalFrame* frame() {
 514     return frame_.GetFrame();
 515   }
 516
 517   const blink::WebNode& node() const {
 518     return node_to_print_;
 519   }
 520
 521   int GetExpectedPageCount() const {
 522     return expected_pages_count_;
 523   }
 524
 525   gfx::Size GetPrintCanvasSize() const;
 526
 527   void FinishPrinting();
 528
 529   bool IsLoadingSelection() {
 530     // It's not selection if not |owns_web_view_|.
 531     return owns_web_view_ && frame() && frame()->isLoading();
 532   }
 533
 534   // TODO(ojan): Remove this override and have this class use a non-null
 535   // layerTreeView.
 536   // blink::WebViewClient override:
 537   virtual bool allowsBrokenNullLayerTreeView() const;
 538
 539  protected:
 540   // blink::WebViewClient override:
 541   virtual void didStopLoading();
 542
 543   // blink::WebFrameClient override:
 544   // TODO(alexmos): Remove once Blink is updated to use sandbox flags.
 545   virtual blink::WebFrame* createChildFrame(blink::WebLocalFrame* parent,
 546                                             const blink::WebString& name);
 547   virtual blink::WebFrame* createChildFrame(
 548       blink::WebLocalFrame* parent,
 549       const blink::WebString& name,
 550       blink::WebSandboxFlags sandboxFlags);
 551   virtual void frameDetached(blink::WebFrame* frame);
 552
 553  private:
 554   void CallOnReady();
 555   void ResizeForPrinting();
 556   void RestoreSize();
 557   void CopySelection(const WebPreferences& preferences);
 558
 559   FrameReference frame_;
 560   blink::WebNode node_to_print_;
 561   bool owns_web_view_;
 562   blink::WebPrintParams web_print_params_;
 563   gfx::Size prev_view_size_;
 564   gfx::Size prev_scroll_offset_;
 565   int expected_pages_count_;
 566   base::Closure on_ready_;
 567   bool should_print_backgrounds_;
 568   bool should_print_selection_only_;
 569   bool is_printing_started_;
 570
 571   base::WeakPtrFactory<PrepareFrameAndViewForPrint> weak_ptr_factory_;
 572
 573   DISALLOW_COPY_AND_ASSIGN(PrepareFrameAndViewForPrint);
 574 };
 575
 576 PrepareFrameAndViewForPrint::PrepareFrameAndViewForPrint(
 577     const PrintMsg_Print_Params& params,
 578     blink::WebLocalFrame* frame,
 579     const blink::WebNode& node,
 580     bool ignore_css_margins)
 581     : frame_(frame),
 582       node_to_print_(node),
 583       owns_web_view_(false),
 584       expected_pages_count_(0),
 585       should_print_backgrounds_(params.should_print_backgrounds),
 586       should_print_selection_only_(params.selection_only),
 587       is_printing_started_(false),
 588       weak_ptr_factory_(this) {
 589   PrintMsg_Print_Params print_params = params;
 590   if (!should_print_selection_only_ ||
 591       !PrintingNodeOrPdfFrame(frame, node_to_print_)) {
 592     bool fit_to_page = ignore_css_margins &&
 593                        print_params.print_scaling_option ==
 594                             blink::WebPrintScalingOptionFitToPrintableArea;
 595     ComputeWebKitPrintParamsInDesiredDpi(params, &web_print_params_);
 596     frame->printBegin(web_print_params_, node_to_print_);
 597     print_params = CalculatePrintParamsForCss(frame, 0, print_params,
 598                                               ignore_css_margins, fit_to_page,
 599                                               NULL);
 600     frame->printEnd();
 601   }
 602   ComputeWebKitPrintParamsInDesiredDpi(print_params, &web_print_params_);
 603 }
 604
 605 PrepareFrameAndViewForPrint::~PrepareFrameAndViewForPrint() {
 606   FinishPrinting();
 607 }
 608
 609 void PrepareFrameAndViewForPrint::ResizeForPrinting() {
 610   // Layout page according to printer page size. Since WebKit shrinks the
 611   // size of the page automatically (from 125% to 200%) we trick it to
 612   // think the page is 125% larger so the size of the page is correct for
 613   // minimum (default) scaling.
 614   // This is important for sites that try to fill the page.
 615   gfx::Size print_layout_size(web_print_params_.printContentArea.width,
 616                               web_print_params_.printContentArea.height);
 617   print_layout_size.set_height(
 618       static_cast<int>(static_cast<double>(print_layout_size.height()) * 1.25));
 619
 620   if (!frame())
 621     return;
 622   blink::WebView* web_view = frame_.view();
 623   // Backup size and offset.
 624   if (blink::WebFrame* web_frame = web_view->mainFrame())
 625     prev_scroll_offset_ = web_frame->scrollOffset();
 626   prev_view_size_ = web_view->size();
 627
 628   web_view->resize(print_layout_size);
 629 }
 630
 631
 632 void PrepareFrameAndViewForPrint::StartPrinting() {
 633   ResizeForPrinting();
 634   blink::WebView* web_view = frame_.view();
 635   web_view->settings()->setShouldPrintBackgrounds(should_print_backgrounds_);
 636   expected_pages_count_ =
 637       frame()->printBegin(web_print_params_, node_to_print_);
 638   is_printing_started_ = true;
 639 }
 640
 641 void PrepareFrameAndViewForPrint::CopySelectionIfNeeded(
 642     const WebPreferences& preferences,
 643     const base::Closure& on_ready) {
 644   on_ready_ = on_ready;
 645   if (should_print_selection_only_)
 646     CopySelection(preferences);
 647   else
 648     didStopLoading();
 649 }
 650
 651 void PrepareFrameAndViewForPrint::CopySelection(
 652     const WebPreferences& preferences) {
 653   ResizeForPrinting();
 654   std::string url_str = "data:text/html;charset=utf-8,";
 655   url_str.append(
 656       net::EscapeQueryParamValue(frame()->selectionAsMarkup().utf8(), false));
 657   RestoreSize();
 658   // Create a new WebView with the same settings as the current display one.
 659   // Except that we disable javascript (don't want any active content running
 660   // on the page).
 661   WebPreferences prefs = preferences;
 662   prefs.javascript_enabled = false;
 663   prefs.java_enabled = false;
 664
 665   blink::WebView* web_view = blink::WebView::create(this);
 666   owns_web_view_ = true;
 667   content::RenderView::ApplyWebPreferences(prefs, web_view);
 668   web_view->setMainFrame(blink::WebLocalFrame::create(this));
 669   frame_.Reset(web_view->mainFrame()->toWebLocalFrame());
 670   node_to_print_.reset();
 671
 672   // When loading is done this will call didStopLoading() and that will do the
 673   // actual printing.
 674   frame()->loadRequest(blink::WebURLRequest(GURL(url_str)));
 675 }
 676
 677 bool PrepareFrameAndViewForPrint::allowsBrokenNullLayerTreeView() const {
 678   return true;
 679 }
 680
 681 void PrepareFrameAndViewForPrint::didStopLoading() {
 682   DCHECK(!on_ready_.is_null());
 683   // Don't call callback here, because it can delete |this| and WebView that is
 684   // called didStopLoading.
 685   base::MessageLoop::current()->PostTask(
 686       FROM_HERE,
 687       base::Bind(&PrepareFrameAndViewForPrint::CallOnReady,
 688                  weak_ptr_factory_.GetWeakPtr()));
 689 }
 690
 691 // TODO(alexmos): Remove once Blink is updated to use sandbox flags.
 692 blink::WebFrame* PrepareFrameAndViewForPrint::createChildFrame(
 693     blink::WebLocalFrame* parent,
 694     const blink::WebString& name) {
 695   return createChildFrame(parent, name, blink::WebSandboxFlags::None);
 696 }
 697
 698 blink::WebFrame* PrepareFrameAndViewForPrint::createChildFrame(
 699     blink::WebLocalFrame* parent,
 700     const blink::WebString& name,
 701     blink::WebSandboxFlags sandboxFlags) {
 702   blink::WebFrame* frame = blink::WebLocalFrame::create(this);
 703   parent->appendChild(frame);
 704   return frame;
 705 }
 706
 707 void PrepareFrameAndViewForPrint::frameDetached(blink::WebFrame* frame) {
 708   if (frame->parent())
 709     frame->parent()->removeChild(frame);
 710   frame->close();
 711 }
 712
 713 void PrepareFrameAndViewForPrint::CallOnReady() {
 714   return on_ready_.Run();  // Can delete |this|.
 715 }
 716
 717 gfx::Size PrepareFrameAndViewForPrint::GetPrintCanvasSize() const {
 718   DCHECK(is_printing_started_);
 719   return gfx::Size(web_print_params_.printContentArea.width,
 720                    web_print_params_.printContentArea.height);
 721 }
 722
 723 void PrepareFrameAndViewForPrint::RestoreSize() {
 724   if (frame()) {
 725     blink::WebView* web_view = frame_.GetFrame()->view();
 726     web_view->resize(prev_view_size_);
 727     if (blink::WebFrame* web_frame = web_view->mainFrame())
 728       web_frame->setScrollOffset(prev_scroll_offset_);
 729   }
 730 }
 731
 732 void PrepareFrameAndViewForPrint::FinishPrinting() {
 733   blink::WebLocalFrame* frame = frame_.GetFrame();
 734   if (frame) {
 735     blink::WebView* web_view = frame->view();
 736     if (is_printing_started_) {
 737       is_printing_started_ = false;
 738       frame->printEnd();
 739       if (!owns_web_view_) {
 740         web_view->settings()->setShouldPrintBackgrounds(false);
 741         RestoreSize();
 742       }
 743     }
 744     if (owns_web_view_) {
 745       DCHECK(!frame->isLoading());
 746       owns_web_view_ = false;
 747       web_view->close();
 748     }
 749   }
 750   frame_.Reset(NULL);
 751   on_ready_.Reset();
 752 }
 753
 754 PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
 755     : content::RenderViewObserver(render_view),
 756       content::RenderViewObserverTracker<PrintWebViewHelper>(render_view),
 757       reset_prep_frame_view_(false),
 758       is_preview_enabled_(IsPrintPreviewEnabled()),
 759       is_scripted_print_throttling_disabled_(IsPrintThrottlingDisabled()),
 760       is_print_ready_metafile_sent_(false),
 761       ignore_css_margins_(false),
 762       user_cancelled_scripted_print_count_(0),
 763       is_scripted_printing_blocked_(false),
 764       notify_browser_of_print_failure_(true),
 765       print_for_preview_(false),
 766       print_node_in_progress_(false),
 767       is_loading_(false),
 768       is_scripted_preview_delayed_(false),
 769       weak_ptr_factory_(this) {
 770   // TODO(sgurun) enable window.print() for webview crbug.com/322303
 771   SetScriptedPrintBlocked(true);
 772 }
 773
 774 PrintWebViewHelper::~PrintWebViewHelper() {}
 775
 776 bool PrintWebViewHelper::IsScriptInitiatedPrintAllowed(
 777     blink::WebFrame* frame, bool user_initiated) {
 778 #if defined(OS_ANDROID)
 779   return false;
 780 #endif  // defined(OS_ANDROID)
 781   if (is_scripted_printing_blocked_)
 782     return false;
 783   // If preview is enabled, then the print dialog is tab modal, and the user
 784   // can always close the tab on a mis-behaving page (the system print dialog
 785   // is app modal). If the print was initiated through user action, don't
 786   // throttle. Or, if the command line flag to skip throttling has been set.
 787   if (!is_scripted_print_throttling_disabled_ &&
 788       !is_preview_enabled_ &&
 789       !user_initiated)
 790     return !IsScriptInitiatedPrintTooFrequent(frame);
 791   return true;
 792 }
 793
 794 void PrintWebViewHelper::DidStartLoading() {
 795   is_loading_ = true;
 796 }
 797
 798 void PrintWebViewHelper::DidStopLoading() {
 799   is_loading_ = false;
 800   ShowScriptedPrintPreview();
 801 }
 802
 803 // Prints |frame| which called window.print().
 804 void PrintWebViewHelper::PrintPage(blink::WebLocalFrame* frame,
 805                                    bool user_initiated) {
 806   DCHECK(frame);
 807
 808 #if !defined(OS_ANDROID)
 809   // TODO(sgurun) android_webview hack
 810   // Allow Prerendering to cancel this print request if necessary.
 811   if (prerender::PrerenderHelper::IsPrerendering(render_view())) {
 812     Send(new ChromeViewHostMsg_CancelPrerenderForPrinting(routing_id()));
 813     return;
 814   }
 815 #endif  // !defined(OS_ANDROID)
 816
 817   if (!IsScriptInitiatedPrintAllowed(frame, user_initiated))
 818     return;
 819   IncrementScriptedPrintCount();
 820
 821   if (is_preview_enabled_) {
 822     print_preview_context_.InitWithFrame(frame);
 823     RequestPrintPreview(PRINT_PREVIEW_SCRIPTED);
 824   } else {
 825     Print(frame, blink::WebNode());
 826   }
 827 }
 828
 829 bool PrintWebViewHelper::OnMessageReceived(const IPC::Message& message) {
 830   bool handled = true;
 831   IPC_BEGIN_MESSAGE_MAP(PrintWebViewHelper, message)
 832     IPC_MESSAGE_HANDLER(PrintMsg_PrintPages, OnPrintPages)
 833     IPC_MESSAGE_HANDLER(PrintMsg_PrintForSystemDialog, OnPrintForSystemDialog)
 834     IPC_MESSAGE_HANDLER(PrintMsg_InitiatePrintPreview, OnInitiatePrintPreview)
 835     IPC_MESSAGE_HANDLER(PrintMsg_PrintPreview, OnPrintPreview)
 836     IPC_MESSAGE_HANDLER(PrintMsg_PrintForPrintPreview, OnPrintForPrintPreview)
 837     IPC_MESSAGE_HANDLER(PrintMsg_PrintingDone, OnPrintingDone)
 838     IPC_MESSAGE_HANDLER(PrintMsg_ResetScriptedPrintCount,
 839                         ResetScriptedPrintCount)
 840     IPC_MESSAGE_HANDLER(PrintMsg_SetScriptedPrintingBlocked,
 841                         SetScriptedPrintBlocked)
 842     IPC_MESSAGE_UNHANDLED(handled = false)
 843     IPC_END_MESSAGE_MAP()
 844   return handled;
 845 }
 846
 847 void PrintWebViewHelper::OnPrintForPrintPreview(
 848     const base::DictionaryValue& job_settings) {
 849   DCHECK(is_preview_enabled_);
 850   // If still not finished with earlier print request simply ignore.
 851   if (prep_frame_view_)
 852     return;
 853
 854   if (!render_view()->GetWebView())
 855     return;
 856   blink::WebFrame* main_frame = render_view()->GetWebView()->mainFrame();
 857   if (!main_frame)
 858     return;
 859
 860   blink::WebDocument document = main_frame->document();
 861   // <object> with id="pdf-viewer" is created in
 862   // chrome/browser/resources/print_preview/print_preview.js
 863   blink::WebElement pdf_element = document.getElementById("pdf-viewer");
 864   if (pdf_element.isNull()) {
 865     NOTREACHED();
 866     return;
 867   }
 868
 869   // Set |print_for_preview_| flag and autoreset it to back to original
 870   // on return.
 871   base::AutoReset<bool> set_printing_flag(&print_for_preview_, true);
 872
 873   blink::WebLocalFrame* pdf_frame = pdf_element.document().frame();
 874   if (!UpdatePrintSettings(pdf_frame, pdf_element, job_settings)) {
 875     LOG(ERROR) << "UpdatePrintSettings failed";
 876     DidFinishPrinting(FAIL_PRINT);
 877     return;
 878   }
 879
 880   // Print page onto entire page not just printable area. Preview PDF already
 881   // has content in correct position taking into account page size and printable
 882   // area.
 883   // TODO(vitalybuka) : Make this consistent on all platform. This change
 884   // affects Windows only. On Linux and OSX RenderPagesForPrint does not use
 885   // printable_area. Also we can't change printable_area deeper inside
 886   // RenderPagesForPrint for Windows, because it's used also by native
 887   // printing and it expects real printable_area value.
 888   // See http://crbug.com/123408
 889   PrintMsg_Print_Params& print_params = print_pages_params_->params;
 890   print_params.printable_area = gfx::Rect(print_params.page_size);
 891
 892   // Render Pages for printing.
 893   if (!RenderPagesForPrint(pdf_frame, pdf_element)) {
 894     LOG(ERROR) << "RenderPagesForPrint failed";
 895     DidFinishPrinting(FAIL_PRINT);
 896   }
 897 }
 898
 899 bool PrintWebViewHelper::GetPrintFrame(blink::WebLocalFrame** frame) {
 900   DCHECK(frame);
 901   blink::WebView* webView = render_view()->GetWebView();
 902   DCHECK(webView);
 903   if (!webView)
 904     return false;
 905
 906   // If the user has selected text in the currently focused frame we print
 907   // only that frame (this makes print selection work for multiple frames).
 908   blink::WebLocalFrame* focusedFrame =
 909       webView->focusedFrame()->toWebLocalFrame();
 910   *frame = focusedFrame->hasSelection()
 911                ? focusedFrame
 912                : webView->mainFrame()->toWebLocalFrame();
 913   return true;
 914 }
 915
 916 void PrintWebViewHelper::OnPrintPages() {
 917   blink::WebLocalFrame* frame;
 918   if (GetPrintFrame(&frame))
 919     Print(frame, blink::WebNode());
 920 }
 921
 922 void PrintWebViewHelper::OnPrintForSystemDialog() {
 923   blink::WebLocalFrame* frame = print_preview_context_.source_frame();
 924   if (!frame) {
 925     NOTREACHED();
 926     return;
 927   }
 928
 929   Print(frame, print_preview_context_.source_node());
 930 }
 931
 932 void PrintWebViewHelper::GetPageSizeAndContentAreaFromPageLayout(
 933     const PageSizeMargins& page_layout_in_points,
 934     gfx::Size* page_size,
 935     gfx::Rect* content_area) {
 936   *page_size = gfx::Size(
 937       page_layout_in_points.content_width +
 938           page_layout_in_points.margin_right +
 939           page_layout_in_points.margin_left,
 940       page_layout_in_points.content_height +
 941           page_layout_in_points.margin_top +
 942           page_layout_in_points.margin_bottom);
 943   *content_area = gfx::Rect(page_layout_in_points.margin_left,
 944                             page_layout_in_points.margin_top,
 945                             page_layout_in_points.content_width,
 946                             page_layout_in_points.content_height);
 947 }
 948
 949 void PrintWebViewHelper::UpdateFrameMarginsCssInfo(
 950     const base::DictionaryValue& settings) {
 951   int margins_type = 0;
 952   if (!settings.GetInteger(kSettingMarginsType, &margins_type))
 953     margins_type = DEFAULT_MARGINS;
 954   ignore_css_margins_ = (margins_type != DEFAULT_MARGINS);
 955 }
 956
 957 bool PrintWebViewHelper::IsPrintToPdfRequested(
 958     const base::DictionaryValue& job_settings) {
 959   bool print_to_pdf = false;
 960   if (!job_settings.GetBoolean(kSettingPrintToPDF, &print_to_pdf))
 961     NOTREACHED();
 962   return print_to_pdf;
 963 }
 964
 965 blink::WebPrintScalingOption PrintWebViewHelper::GetPrintScalingOption(
 966     bool source_is_html, const base::DictionaryValue& job_settings,
 967     const PrintMsg_Print_Params& params) {
 968   DCHECK(!print_for_preview_);
 969
 970   if (params.print_to_pdf)
 971     return blink::WebPrintScalingOptionSourceSize;
 972
 973   if (!source_is_html) {
 974     if (!FitToPageEnabled(job_settings))
 975       return blink::WebPrintScalingOptionNone;
 976
 977     bool no_plugin_scaling =
 978         print_preview_context_.source_frame()->isPrintScalingDisabledForPlugin(
 979             print_preview_context_.source_node());
 980
 981     if (params.is_first_request && no_plugin_scaling)
 982       return blink::WebPrintScalingOptionNone;
 983   }
 984   return blink::WebPrintScalingOptionFitToPrintableArea;
 985 }
 986
 987 void PrintWebViewHelper::OnPrintPreview(const base::DictionaryValue& settings) {
 988   DCHECK(is_preview_enabled_);
 989   print_preview_context_.OnPrintPreview();
 990
 991   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
 992                             PREVIEW_EVENT_REQUESTED, PREVIEW_EVENT_MAX);
 993
 994   if (!UpdatePrintSettings(print_preview_context_.source_frame(),
 995                            print_preview_context_.source_node(), settings)) {
 996     if (print_preview_context_.last_error() != PREVIEW_ERROR_BAD_SETTING) {
 997       Send(new PrintHostMsg_PrintPreviewInvalidPrinterSettings(
 998           routing_id(), print_pages_params_->params.document_cookie));
 999       notify_browser_of_print_failure_ = false;  // Already sent.
1000     }
1001     DidFinishPrinting(FAIL_PREVIEW);
1002     return;
1003   }
1004
1005   // If we are previewing a pdf and the print scaling is disabled, send a
1006   // message to browser.
1007   if (print_pages_params_->params.is_first_request &&
1008       !print_preview_context_.IsModifiable() &&
1009       print_preview_context_.source_frame()->isPrintScalingDisabledForPlugin(
1010           print_preview_context_.source_node())) {
1011     Send(new PrintHostMsg_PrintPreviewScalingDisabled(routing_id()));
1012   }
1013
1014   is_print_ready_metafile_sent_ = false;
1015
1016   // PDF printer device supports alpha blending.
1017   print_pages_params_->params.supports_alpha_blend = true;
1018
1019   bool generate_draft_pages = false;
1020   if (!settings.GetBoolean(kSettingGenerateDraftData,
1021                            &generate_draft_pages)) {
1022     NOTREACHED();
1023   }
1024   print_preview_context_.set_generate_draft_pages(generate_draft_pages);
1025
1026   PrepareFrameForPreviewDocument();
1027 }
1028
1029 void PrintWebViewHelper::PrepareFrameForPreviewDocument() {
1030   reset_prep_frame_view_ = false;
1031
1032   if (!print_pages_params_ || CheckForCancel()) {
1033     DidFinishPrinting(FAIL_PREVIEW);
1034     return;
1035   }
1036
1037   // Don't reset loading frame or WebKit will fail assert. Just retry when
1038   // current selection is loaded.
1039   if (prep_frame_view_ && prep_frame_view_->IsLoadingSelection()) {
1040     reset_prep_frame_view_ = true;
1041     return;
1042   }
1043
1044   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1045   prep_frame_view_.reset(
1046       new PrepareFrameAndViewForPrint(print_params,
1047                                       print_preview_context_.source_frame(),
1048                                       print_preview_context_.source_node(),
1049                                       ignore_css_margins_));
1050   prep_frame_view_->CopySelectionIfNeeded(
1051       render_view()->GetWebkitPreferences(),
1052       base::Bind(&PrintWebViewHelper::OnFramePreparedForPreviewDocument,
1053                  base::Unretained(this)));
1054 }
1055
1056 void PrintWebViewHelper::OnFramePreparedForPreviewDocument() {
1057   if (reset_prep_frame_view_) {
1058     PrepareFrameForPreviewDocument();
1059     return;
1060   }
1061   DidFinishPrinting(CreatePreviewDocument() ? OK : FAIL_PREVIEW);
1062 }
1063
1064 bool PrintWebViewHelper::CreatePreviewDocument() {
1065   if (!print_pages_params_ || CheckForCancel())
1066     return false;
1067
1068   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
1069                             PREVIEW_EVENT_CREATE_DOCUMENT, PREVIEW_EVENT_MAX);
1070
1071   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1072   const std::vector<int>& pages = print_pages_params_->pages;
1073
1074   if (!print_preview_context_.CreatePreviewDocument(prep_frame_view_.release(),
1075                                                     pages)) {
1076     return false;
1077   }
1078
1079   PageSizeMargins default_page_layout;
1080   ComputePageLayoutInPointsForCss(print_preview_context_.prepared_frame(), 0,
1081                                   print_params, ignore_css_margins_, NULL,
1082                                   &default_page_layout);
1083
1084   bool has_page_size_style = PrintingFrameHasPageSizeStyle(
1085       print_preview_context_.prepared_frame(),
1086       print_preview_context_.total_page_count());
1087   int dpi = GetDPI(&print_params);
1088
1089   gfx::Rect printable_area_in_points(
1090       ConvertUnit(print_params.printable_area.x(), dpi, kPointsPerInch),
1091       ConvertUnit(print_params.printable_area.y(), dpi, kPointsPerInch),
1092       ConvertUnit(print_params.printable_area.width(), dpi, kPointsPerInch),
1093       ConvertUnit(print_params.printable_area.height(), dpi, kPointsPerInch));
1094
1095   // Margins: Send default page layout to browser process.
1096   Send(new PrintHostMsg_DidGetDefaultPageLayout(routing_id(),
1097                                                 default_page_layout,
1098                                                 printable_area_in_points,
1099                                                 has_page_size_style));
1100
1101   PrintHostMsg_DidGetPreviewPageCount_Params params;
1102   params.page_count = print_preview_context_.total_page_count();
1103   params.is_modifiable = print_preview_context_.IsModifiable();
1104   params.document_cookie = print_params.document_cookie;
1105   params.preview_request_id = print_params.preview_request_id;
1106   params.clear_preview_data = print_preview_context_.generate_draft_pages();
1107   Send(new PrintHostMsg_DidGetPreviewPageCount(routing_id(), params));
1108   if (CheckForCancel())
1109     return false;
1110
1111   while (!print_preview_context_.IsFinalPageRendered()) {
1112     int page_number = print_preview_context_.GetNextPageNumber();
1113     DCHECK_GE(page_number, 0);
1114     if (!RenderPreviewPage(page_number, print_params))
1115       return false;
1116
1117     if (CheckForCancel())
1118       return false;
1119
1120     // We must call PrepareFrameAndViewForPrint::FinishPrinting() (by way of
1121     // print_preview_context_.AllPagesRendered()) before calling
1122     // FinalizePrintReadyDocument() when printing a PDF because the plugin
1123     // code does not generate output until we call FinishPrinting().  We do not
1124     // generate draft pages for PDFs, so IsFinalPageRendered() and
1125     // IsLastPageOfPrintReadyMetafile() will be true in the same iteration of
1126     // the loop.
1127     if (print_preview_context_.IsFinalPageRendered())
1128       print_preview_context_.AllPagesRendered();
1129
1130     if (print_preview_context_.IsLastPageOfPrintReadyMetafile()) {
1131       DCHECK(print_preview_context_.IsModifiable() ||
1132              print_preview_context_.IsFinalPageRendered());
1133       if (!FinalizePrintReadyDocument())
1134         return false;
1135     }
1136   }
1137   print_preview_context_.Finished();
1138   return true;
1139 }
1140
1141 bool PrintWebViewHelper::FinalizePrintReadyDocument() {
1142   DCHECK(!is_print_ready_metafile_sent_);
1143   print_preview_context_.FinalizePrintReadyDocument();
1144
1145   // Get the size of the resulting metafile.
1146   PdfMetafileSkia* metafile = print_preview_context_.metafile();
1147   uint32 buf_size = metafile->GetDataSize();
1148   DCHECK_GT(buf_size, 0u);
1149
1150   PrintHostMsg_DidPreviewDocument_Params preview_params;
1151   preview_params.reuse_existing_data = false;
1152   preview_params.data_size = buf_size;
1153   preview_params.document_cookie = print_pages_params_->params.document_cookie;
1154   preview_params.expected_pages_count =
1155       print_preview_context_.total_page_count();
1156   preview_params.modifiable = print_preview_context_.IsModifiable();
1157   preview_params.preview_request_id =
1158       print_pages_params_->params.preview_request_id;
1159
1160   // Ask the browser to create the shared memory for us.
1161   if (!CopyMetafileDataToSharedMem(metafile,
1162                                    &(preview_params.metafile_data_handle))) {
1163     LOG(ERROR) << "CopyMetafileDataToSharedMem failed";
1164     print_preview_context_.set_error(PREVIEW_ERROR_METAFILE_COPY_FAILED);
1165     return false;
1166   }
1167   is_print_ready_metafile_sent_ = true;
1168
1169   Send(new PrintHostMsg_MetafileReadyForPrinting(routing_id(), preview_params));
1170   return true;
1171 }
1172
1173 void PrintWebViewHelper::OnPrintingDone(bool success) {
1174   notify_browser_of_print_failure_ = false;
1175   if (!success)
1176     LOG(ERROR) << "Failure in OnPrintingDone";
1177   DidFinishPrinting(success ? OK : FAIL_PRINT);
1178 }
1179
1180 void PrintWebViewHelper::SetScriptedPrintBlocked(bool blocked) {
1181   is_scripted_printing_blocked_ = blocked;
1182 }
1183
1184 void PrintWebViewHelper::OnInitiatePrintPreview(bool selection_only) {
1185   DCHECK(is_preview_enabled_);
1186   blink::WebLocalFrame* frame = NULL;
1187   GetPrintFrame(&frame);
1188   DCHECK(frame);
1189   print_preview_context_.InitWithFrame(frame);
1190   RequestPrintPreview(selection_only ?
1191                       PRINT_PREVIEW_USER_INITIATED_SELECTION :
1192                       PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME);
1193 }
1194
1195 bool PrintWebViewHelper::IsPrintingEnabled() {
1196   bool result = false;
1197   Send(new PrintHostMsg_IsPrintingEnabled(routing_id(), &result));
1198   return result;
1199 }
1200
1201 void PrintWebViewHelper::PrintNode(const blink::WebNode& node) {
1202   if (node.isNull() || !node.document().frame()) {
1203     // This can occur when the context menu refers to an invalid WebNode.
1204     // See http://crbug.com/100890#c17 for a repro case.
1205     return;
1206   }
1207
1208   if (print_node_in_progress_) {
1209     // This can happen as a result of processing sync messages when printing
1210     // from ppapi plugins. It's a rare case, so its OK to just fail here.
1211     // See http://crbug.com/159165.
1212     return;
1213   }
1214
1215   print_node_in_progress_ = true;
1216
1217   // Make a copy of the node, in case RenderView::OnContextMenuClosed resets
1218   // its |context_menu_node_|.
1219   if (is_preview_enabled_) {
1220     print_preview_context_.InitWithNode(node);
1221     RequestPrintPreview(PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE);
1222   } else {
1223     blink::WebNode duplicate_node(node);
1224     Print(duplicate_node.document().frame(), duplicate_node);
1225   }
1226
1227   print_node_in_progress_ = false;
1228 }
1229
1230 void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
1231                                const blink::WebNode& node) {
1232   // If still not finished with earlier print request simply ignore.
1233   if (prep_frame_view_)
1234     return;
1235
1236   FrameReference frame_ref(frame);
1237
1238   int expected_page_count = 0;
1239   if (!CalculateNumberOfPages(frame, node, &expected_page_count)) {
1240     DidFinishPrinting(FAIL_PRINT_INIT);
1241     return;  // Failed to init print page settings.
1242   }
1243
1244   // Some full screen plugins can say they don't want to print.
1245   if (!expected_page_count) {
1246     DidFinishPrinting(FAIL_PRINT);
1247     return;
1248   }
1249
1250 #if !defined(OS_ANDROID)
1251   // TODO(sgurun) android_webview hack
1252   // Ask the browser to show UI to retrieve the final print settings.
1253   if (!GetPrintSettingsFromUser(frame_ref.GetFrame(), node,
1254                                 expected_page_count)) {
1255     DidFinishPrinting(OK);  // Release resources and fail silently.
1256     return;
1257   }
1258 #endif  // !defined(OS_ANDROID)
1259
1260   // Render Pages for printing.
1261   if (!RenderPagesForPrint(frame_ref.GetFrame(), node)) {
1262     LOG(ERROR) << "RenderPagesForPrint failed";
1263     DidFinishPrinting(FAIL_PRINT);
1264   }
1265   ResetScriptedPrintCount();
1266 }
1267
1268 void PrintWebViewHelper::DidFinishPrinting(PrintingResult result) {
1269   switch (result) {
1270     case OK:
1271       break;
1272
1273     case FAIL_PRINT_INIT:
1274       DCHECK(!notify_browser_of_print_failure_);
1275       break;
1276
1277     case FAIL_PRINT:
1278       if (notify_browser_of_print_failure_ && print_pages_params_.get()) {
1279         int cookie = print_pages_params_->params.document_cookie;
1280         Send(new PrintHostMsg_PrintingFailed(routing_id(), cookie));
1281       }
1282       break;
1283
1284     case FAIL_PREVIEW:
1285       DCHECK(is_preview_enabled_);
1286       int cookie = print_pages_params_.get() ?
1287           print_pages_params_->params.document_cookie : 0;
1288       if (notify_browser_of_print_failure_) {
1289         LOG(ERROR) << "CreatePreviewDocument failed";
1290         Send(new PrintHostMsg_PrintPreviewFailed(routing_id(), cookie));
1291       } else {
1292         Send(new PrintHostMsg_PrintPreviewCancelled(routing_id(), cookie));
1293       }
1294       print_preview_context_.Failed(notify_browser_of_print_failure_);
1295       break;
1296   }
1297
1298   prep_frame_view_.reset();
1299   print_pages_params_.reset();
1300   notify_browser_of_print_failure_ = true;
1301 }
1302
1303 void PrintWebViewHelper::OnFramePreparedForPrintPages() {
1304   PrintPages();
1305   FinishFramePrinting();
1306 }
1307
1308 void PrintWebViewHelper::PrintPages() {
1309   if (!prep_frame_view_)  // Printing is already canceled or failed.
1310     return;
1311   prep_frame_view_->StartPrinting();
1312
1313   int page_count = prep_frame_view_->GetExpectedPageCount();
1314   if (!page_count) {
1315     LOG(ERROR) << "Can't print 0 pages.";
1316     return DidFinishPrinting(FAIL_PRINT);
1317   }
1318
1319   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1320   const PrintMsg_Print_Params& print_params = params.params;
1321
1322 #if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
1323   // TODO(vitalybuka): should be page_count or valid pages from params.pages.
1324   // See http://crbug.com/161576
1325   Send(new PrintHostMsg_DidGetPrintedPagesCount(routing_id(),
1326                                                 print_params.document_cookie,
1327                                                 page_count));
1328 #endif  // !defined(OS_CHROMEOS)
1329
1330   if (print_params.preview_ui_id < 0) {
1331     // Printing for system dialog.
1332     int printed_count = params.pages.empty() ? page_count : params.pages.size();
1333 #if !defined(OS_CHROMEOS)
1334     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.SystemDialog", printed_count);
1335 #else
1336     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.PrintToCloudPrintWebDialog",
1337                          printed_count);
1338 #endif  // !defined(OS_CHROMEOS)
1339   }
1340
1341
1342   if (!PrintPagesNative(prep_frame_view_->frame(), page_count,
1343                         prep_frame_view_->GetPrintCanvasSize())) {
1344     LOG(ERROR) << "Printing failed.";
1345     return DidFinishPrinting(FAIL_PRINT);
1346   }
1347 }
1348
1349 void PrintWebViewHelper::FinishFramePrinting() {
1350   prep_frame_view_.reset();
1351 }
1352
1353 #if defined(OS_MACOSX) || defined(OS_WIN)
1354 bool PrintWebViewHelper::PrintPagesNative(blink::WebFrame* frame,
1355                                           int page_count,
1356                                           const gfx::Size& canvas_size) {
1357   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1358   const PrintMsg_Print_Params& print_params = params.params;
1359
1360   PrintMsg_PrintPage_Params page_params;
1361   page_params.params = print_params;
1362   if (params.pages.empty()) {
1363     for (int i = 0; i < page_count; ++i) {
1364       page_params.page_number = i;
1365       PrintPageInternal(page_params, canvas_size, frame);
1366     }
1367   } else {
1368     for (size_t i = 0; i < params.pages.size(); ++i) {
1369       if (params.pages[i] >= page_count)
1370         break;
1371       page_params.page_number = params.pages[i];
1372       PrintPageInternal(page_params, canvas_size, frame);
1373     }
1374   }
1375   return true;
1376 }
1377
1378 #endif  // OS_MACOSX || OS_WIN
1379
1380 // static - Not anonymous so that platform implementations can use it.
1381 void PrintWebViewHelper::ComputePageLayoutInPointsForCss(
1382     blink::WebFrame* frame,
1383     int page_index,
1384     const PrintMsg_Print_Params& page_params,
1385     bool ignore_css_margins,
1386     double* scale_factor,
1387     PageSizeMargins* page_layout_in_points) {
1388   PrintMsg_Print_Params params = CalculatePrintParamsForCss(
1389       frame, page_index, page_params, ignore_css_margins,
1390       page_params.print_scaling_option ==
1391           blink::WebPrintScalingOptionFitToPrintableArea,
1392       scale_factor);
1393   CalculatePageLayoutFromPrintParams(params, page_layout_in_points);
1394 }
1395
1396 bool PrintWebViewHelper::InitPrintSettings(bool fit_to_paper_size) {
1397   PrintMsg_PrintPages_Params settings;
1398   Send(new PrintHostMsg_GetDefaultPrintSettings(routing_id(),
1399                                                 &settings.params));
1400   // Check if the printer returned any settings, if the settings is empty, we
1401   // can safely assume there are no printer drivers configured. So we safely
1402   // terminate.
1403   bool result = true;
1404   if (!PrintMsg_Print_Params_IsValid(settings.params))
1405     result = false;
1406
1407   if (result &&
1408       (settings.params.dpi < kMinDpi || settings.params.document_cookie == 0)) {
1409     // Invalid print page settings.
1410     NOTREACHED();
1411     result = false;
1412   }
1413
1414   // Reset to default values.
1415   ignore_css_margins_ = false;
1416   settings.pages.clear();
1417
1418   settings.params.print_scaling_option =
1419       blink::WebPrintScalingOptionSourceSize;
1420   if (fit_to_paper_size) {
1421     settings.params.print_scaling_option =
1422         blink::WebPrintScalingOptionFitToPrintableArea;
1423   }
1424
1425   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1426   return result;
1427 }
1428
1429 bool PrintWebViewHelper::CalculateNumberOfPages(blink::WebLocalFrame* frame,
1430                                                 const blink::WebNode& node,
1431                                                 int* number_of_pages) {
1432   DCHECK(frame);
1433   bool fit_to_paper_size = !(PrintingNodeOrPdfFrame(frame, node));
1434   if (!InitPrintSettings(fit_to_paper_size)) {
1435     notify_browser_of_print_failure_ = false;
1436 #if !defined(OS_ANDROID)
1437     // TODO(sgurun) android_webview hack
1438     render_view()->RunModalAlertDialog(
1439         frame,
1440         l10n_util::GetStringUTF16(IDS_PRINT_INVALID_PRINTER_SETTINGS));
1441 #endif  //  !defined(OS_ANDROID)
1442     return false;
1443   }
1444
1445   const PrintMsg_Print_Params& params = print_pages_params_->params;
1446   PrepareFrameAndViewForPrint prepare(params, frame, node, ignore_css_margins_);
1447   prepare.StartPrinting();
1448
1449   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
1450                                              params.document_cookie));
1451   *number_of_pages = prepare.GetExpectedPageCount();
1452   return true;
1453 }
1454
1455 bool PrintWebViewHelper::UpdatePrintSettings(
1456     blink::WebLocalFrame* frame,
1457     const blink::WebNode& node,
1458     const base::DictionaryValue& passed_job_settings) {
1459   DCHECK(is_preview_enabled_);
1460   const base::DictionaryValue* job_settings = &passed_job_settings;
1461   base::DictionaryValue modified_job_settings;
1462   if (job_settings->empty()) {
1463     if (!print_for_preview_)
1464       print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1465     return false;
1466   }
1467
1468   bool source_is_html = true;
1469   if (print_for_preview_) {
1470     if (!job_settings->GetBoolean(kSettingPreviewModifiable, &source_is_html)) {
1471       NOTREACHED();
1472     }
1473   } else {
1474     source_is_html = !PrintingNodeOrPdfFrame(frame, node);
1475   }
1476
1477   if (print_for_preview_ || !source_is_html) {
1478     modified_job_settings.MergeDictionary(job_settings);
1479     modified_job_settings.SetBoolean(kSettingHeaderFooterEnabled, false);
1480     modified_job_settings.SetInteger(kSettingMarginsType, NO_MARGINS);
1481     job_settings = &modified_job_settings;
1482   }
1483
1484   // Send the cookie so that UpdatePrintSettings can reuse PrinterQuery when
1485   // possible.
1486   int cookie = print_pages_params_.get() ?
1487       print_pages_params_->params.document_cookie : 0;
1488   PrintMsg_PrintPages_Params settings;
1489   Send(new PrintHostMsg_UpdatePrintSettings(routing_id(), cookie, *job_settings,
1490                                             &settings));
1491   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1492
1493   if (!PrintMsg_Print_Params_IsValid(settings.params)) {
1494     if (!print_for_preview_) {
1495       print_preview_context_.set_error(PREVIEW_ERROR_INVALID_PRINTER_SETTINGS);
1496     } else {
1497 #if !defined(OS_ANDROID)
1498       // TODO(sgurun) android_webview hack
1499       // PrintForPrintPreview
1500       blink::WebFrame* print_frame = NULL;
1501       // This may not be the right frame, but the alert will be modal,
1502       // therefore it works well enough.
1503       GetPrintFrame(&print_frame);
1504       if (print_frame) {
1505         render_view()->RunModalAlertDialog(
1506             print_frame,
1507             l10n_util::GetStringUTF16(
1508                 IDS_PRINT_INVALID_PRINTER_SETTINGS));
1509       }
1510 #endif  // !defined(OS_ANDROID)
1511     }
1512     return false;
1513   }
1514
1515   if (settings.params.dpi < kMinDpi || !settings.params.document_cookie) {
1516     print_preview_context_.set_error(PREVIEW_ERROR_UPDATING_PRINT_SETTINGS);
1517     return false;
1518   }
1519
1520   if (!job_settings->GetInteger(kPreviewUIID, &settings.params.preview_ui_id)) {
1521     NOTREACHED();
1522     print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1523     return false;
1524   }
1525
1526   if (!print_for_preview_) {
1527     // Validate expected print preview settings.
1528     if (!job_settings->GetInteger(kPreviewRequestID,
1529                                   &settings.params.preview_request_id) ||
1530         !job_settings->GetBoolean(kIsFirstRequest,
1531                                   &settings.params.is_first_request)) {
1532       NOTREACHED();
1533       print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1534       return false;
1535     }
1536
1537     settings.params.print_to_pdf = IsPrintToPdfRequested(*job_settings);
1538     UpdateFrameMarginsCssInfo(*job_settings);
1539     settings.params.print_scaling_option = GetPrintScalingOption(
1540         source_is_html, *job_settings, settings.params);
1541
1542     // Header/Footer: Set |header_footer_info_|.
1543     if (settings.params.display_header_footer) {
1544       header_footer_info_.reset(new base::DictionaryValue());
1545       header_footer_info_->SetDouble(kSettingHeaderFooterDate,
1546                                      base::Time::Now().ToJsTime());
1547       header_footer_info_->SetString(kSettingHeaderFooterURL,
1548                                      settings.params.url);
1549       header_footer_info_->SetString(kSettingHeaderFooterTitle,
1550                                      settings.params.title);
1551     }
1552   }
1553
1554   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1555   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
1556                                              settings.params.document_cookie));
1557
1558   return true;
1559 }
1560
1561 bool PrintWebViewHelper::GetPrintSettingsFromUser(blink::WebFrame* frame,
1562                                                   const blink::WebNode& node,
1563                                                   int expected_pages_count) {
1564   PrintHostMsg_ScriptedPrint_Params params;
1565   PrintMsg_PrintPages_Params print_settings;
1566
1567   params.cookie = print_pages_params_->params.document_cookie;
1568   params.has_selection = frame->hasSelection();
1569   params.expected_pages_count = expected_pages_count;
1570   MarginType margin_type = DEFAULT_MARGINS;
1571   if (PrintingNodeOrPdfFrame(frame, node))
1572     margin_type = GetMarginsForPdf(frame, node);
1573   params.margin_type = margin_type;
1574
1575   Send(new PrintHostMsg_DidShowPrintDialog(routing_id()));
1576
1577   // PrintHostMsg_ScriptedPrint will reset print_scaling_option, so we save the
1578   // value before and restore it afterwards.
1579   blink::WebPrintScalingOption scaling_option =
1580       print_pages_params_->params.print_scaling_option;
1581
1582   print_pages_params_.reset();
1583   IPC::SyncMessage* msg =
1584       new PrintHostMsg_ScriptedPrint(routing_id(), params, &print_settings);
1585   msg->EnableMessagePumping();
1586   Send(msg);
1587   print_pages_params_.reset(new PrintMsg_PrintPages_Params(print_settings));
1588
1589   print_pages_params_->params.print_scaling_option = scaling_option;
1590   return (print_settings.params.dpi && print_settings.params.document_cookie);
1591 }
1592
1593 bool PrintWebViewHelper::RenderPagesForPrint(blink::WebLocalFrame* frame,
1594                                              const blink::WebNode& node) {
1595   if (!frame || prep_frame_view_)
1596     return false;
1597   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1598   const PrintMsg_Print_Params& print_params = params.params;
1599   prep_frame_view_.reset(new PrepareFrameAndViewForPrint(
1600       print_params, frame, node, ignore_css_margins_));
1601   DCHECK(!print_pages_params_->params.selection_only ||
1602          print_pages_params_->pages.empty());
1603   prep_frame_view_->CopySelectionIfNeeded(
1604       render_view()->GetWebkitPreferences(),
1605       base::Bind(&PrintWebViewHelper::OnFramePreparedForPrintPages,
1606                  base::Unretained(this)));
1607   return true;
1608 }
1609
1610 #if defined(OS_POSIX)
1611 bool PrintWebViewHelper::CopyMetafileDataToSharedMem(
1612     PdfMetafileSkia* metafile,
1613     base::SharedMemoryHandle* shared_mem_handle) {
1614   uint32 buf_size = metafile->GetDataSize();
1615   scoped_ptr<base::SharedMemory> shared_buf(
1616       content::RenderThread::Get()->HostAllocateSharedMemoryBuffer(
1617           buf_size).release());
1618
1619   if (shared_buf.get()) {
1620     if (shared_buf->Map(buf_size)) {
1621       metafile->GetData(shared_buf->memory(), buf_size);
1622       shared_buf->GiveToProcess(base::GetCurrentProcessHandle(),
1623                                 shared_mem_handle);
1624       return true;
1625     }
1626   }
1627   NOTREACHED();
1628   return false;
1629 }
1630 #endif  // defined(OS_POSIX)
1631
1632 bool PrintWebViewHelper::IsScriptInitiatedPrintTooFrequent(
1633     blink::WebFrame* frame) {
1634   const int kMinSecondsToIgnoreJavascriptInitiatedPrint = 2;
1635   const int kMaxSecondsToIgnoreJavascriptInitiatedPrint = 32;
1636   bool too_frequent = false;
1637
1638   // Check if there is script repeatedly trying to print and ignore it if too
1639   // frequent.  The first 3 times, we use a constant wait time, but if this
1640   // gets excessive, we switch to exponential wait time. So for a page that
1641   // calls print() in a loop the user will need to cancel the print dialog
1642   // after: [2, 2, 2, 4, 8, 16, 32, 32, ...] seconds.
1643   // This gives the user time to navigate from the page.
1644   if (user_cancelled_scripted_print_count_ > 0) {
1645     base::TimeDelta diff = base::Time::Now() - last_cancelled_script_print_;
1646     int min_wait_seconds = kMinSecondsToIgnoreJavascriptInitiatedPrint;
1647     if (user_cancelled_scripted_print_count_ > 3) {
1648       min_wait_seconds = std::min(
1649           kMinSecondsToIgnoreJavascriptInitiatedPrint <<
1650               (user_cancelled_scripted_print_count_ - 3),
1651           kMaxSecondsToIgnoreJavascriptInitiatedPrint);
1652     }
1653     if (diff.InSeconds() < min_wait_seconds) {
1654       too_frequent = true;
1655     }
1656   }
1657
1658   if (!too_frequent)
1659     return false;
1660
1661   blink::WebString message(
1662       blink::WebString::fromUTF8("Ignoring too frequent calls to print()."));
1663   frame->addMessageToConsole(
1664       blink::WebConsoleMessage(
1665           blink::WebConsoleMessage::LevelWarning, message));
1666   return true;
1667 }
1668
1669 void PrintWebViewHelper::ResetScriptedPrintCount() {
1670   // Reset cancel counter on successful print.
1671   user_cancelled_scripted_print_count_ = 0;
1672 }
1673
1674 void PrintWebViewHelper::IncrementScriptedPrintCount() {
1675   ++user_cancelled_scripted_print_count_;
1676   last_cancelled_script_print_ = base::Time::Now();
1677 }
1678
1679 void PrintWebViewHelper::ShowScriptedPrintPreview() {
1680   if (is_scripted_preview_delayed_) {
1681     is_scripted_preview_delayed_ = false;
1682     Send(new PrintHostMsg_ShowScriptedPrintPreview(routing_id(),
1683             print_preview_context_.IsModifiable()));
1684   }
1685 }
1686
1687 void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
1688   const bool is_modifiable = print_preview_context_.IsModifiable();
1689   const bool has_selection = print_preview_context_.HasSelection();
1690   PrintHostMsg_RequestPrintPreview_Params params;
1691   params.is_modifiable = is_modifiable;
1692   params.has_selection = has_selection;
1693   switch (type) {
1694     case PRINT_PREVIEW_SCRIPTED: {
1695       // Shows scripted print preview in two stages.
1696       // 1. PrintHostMsg_SetupScriptedPrintPreview blocks this call and JS by
1697       //    pumping messages here.
1698       // 2. PrintHostMsg_ShowScriptedPrintPreview shows preview once the
1699       //    document has been loaded.
1700       is_scripted_preview_delayed_ = true;
1701       if (is_loading_ && GetPlugin(print_preview_context_.source_frame())) {
1702         // Wait for DidStopLoading. Plugins may not know the correct
1703         // |is_modifiable| value until they are fully loaded, which occurs when
1704         // DidStopLoading() is called. Defer showing the preview until then.
1705       } else {
1706         base::MessageLoop::current()->PostTask(
1707             FROM_HERE,
1708             base::Bind(&PrintWebViewHelper::ShowScriptedPrintPreview,
1709                        weak_ptr_factory_.GetWeakPtr()));
1710       }
1711       IPC::SyncMessage* msg =
1712           new PrintHostMsg_SetupScriptedPrintPreview(routing_id());
1713       msg->EnableMessagePumping();
1714       Send(msg);
1715       is_scripted_preview_delayed_ = false;
1716       return;
1717     }
1718     case PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME: {
1719       break;
1720     }
1721     case PRINT_PREVIEW_USER_INITIATED_SELECTION: {
1722       DCHECK(has_selection);
1723       params.selection_only = has_selection;
1724       break;
1725     }
1726     case PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE: {
1727       params.webnode_only = true;
1728       break;
1729     }
1730     default: {
1731       NOTREACHED();
1732       return;
1733     }
1734   }
1735   Send(new PrintHostMsg_RequestPrintPreview(routing_id(), params));
1736 }
1737
1738 bool PrintWebViewHelper::CheckForCancel() {
1739   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1740   bool cancel = false;
1741   Send(new PrintHostMsg_CheckForCancel(routing_id(),
1742                                        print_params.preview_ui_id,
1743                                        print_params.preview_request_id,
1744                                        &cancel));
1745   if (cancel)
1746     notify_browser_of_print_failure_ = false;
1747   return cancel;
1748 }
1749
1750 bool PrintWebViewHelper::PreviewPageRendered(int page_number,
1751                                              PdfMetafileSkia* metafile) {
1752   DCHECK_GE(page_number, FIRST_PAGE_INDEX);
1753
1754   // For non-modifiable files, |metafile| should be NULL, so do not bother
1755   // sending a message. If we don't generate draft metafiles, |metafile| is
1756   // NULL.
1757   if (!print_preview_context_.IsModifiable() ||
1758       !print_preview_context_.generate_draft_pages()) {
1759     DCHECK(!metafile);
1760     return true;
1761   }
1762
1763   if (!metafile) {
1764     NOTREACHED();
1765     print_preview_context_.set_error(
1766         PREVIEW_ERROR_PAGE_RENDERED_WITHOUT_METAFILE);
1767     return false;
1768   }
1769
1770   PrintHostMsg_DidPreviewPage_Params preview_page_params;
1771   // Get the size of the resulting metafile.
1772   uint32 buf_size = metafile->GetDataSize();
1773   DCHECK_GT(buf_size, 0u);
1774   if (!CopyMetafileDataToSharedMem(
1775       metafile, &(preview_page_params.metafile_data_handle))) {
1776     LOG(ERROR) << "CopyMetafileDataToSharedMem failed";
1777     print_preview_context_.set_error(PREVIEW_ERROR_METAFILE_COPY_FAILED);
1778     return false;
1779   }
1780   preview_page_params.data_size = buf_size;
1781   preview_page_params.page_number = page_number;
1782   preview_page_params.preview_request_id =
1783       print_pages_params_->params.preview_request_id;
1784
1785   Send(new PrintHostMsg_DidPreviewPage(routing_id(), preview_page_params));
1786   return true;
1787 }
1788
1789 PrintWebViewHelper::PrintPreviewContext::PrintPreviewContext()
1790     : total_page_count_(0),
1791       current_page_index_(0),
1792       generate_draft_pages_(true),
1793       print_ready_metafile_page_count_(0),
1794       error_(PREVIEW_ERROR_NONE),
1795       state_(UNINITIALIZED) {
1796 }
1797
1798 PrintWebViewHelper::PrintPreviewContext::~PrintPreviewContext() {
1799 }
1800
1801 void PrintWebViewHelper::PrintPreviewContext::InitWithFrame(
1802     blink::WebLocalFrame* web_frame) {
1803   DCHECK(web_frame);
1804   DCHECK(!IsRendering());
1805   state_ = INITIALIZED;
1806   source_frame_.Reset(web_frame);
1807   source_node_.reset();
1808 }
1809
1810 void PrintWebViewHelper::PrintPreviewContext::InitWithNode(
1811     const blink::WebNode& web_node) {
1812   DCHECK(!web_node.isNull());
1813   DCHECK(web_node.document().frame());
1814   DCHECK(!IsRendering());
1815   state_ = INITIALIZED;
1816   source_frame_.Reset(web_node.document().frame());
1817   source_node_ = web_node;
1818 }
1819
1820 void PrintWebViewHelper::PrintPreviewContext::OnPrintPreview() {
1821   DCHECK_EQ(INITIALIZED, state_);
1822   ClearContext();
1823 }
1824
1825 bool PrintWebViewHelper::PrintPreviewContext::CreatePreviewDocument(
1826     PrepareFrameAndViewForPrint* prepared_frame,
1827     const std::vector<int>& pages) {
1828   DCHECK_EQ(INITIALIZED, state_);
1829   state_ = RENDERING;
1830
1831   // Need to make sure old object gets destroyed first.
1832   prep_frame_view_.reset(prepared_frame);
1833   prep_frame_view_->StartPrinting();
1834
1835   total_page_count_ = prep_frame_view_->GetExpectedPageCount();
1836   if (total_page_count_ == 0) {
1837     LOG(ERROR) << "CreatePreviewDocument got 0 page count";
1838     set_error(PREVIEW_ERROR_ZERO_PAGES);
1839     return false;
1840   }
1841
1842   metafile_.reset(new PdfMetafileSkia);
1843   if (!metafile_->Init()) {
1844     set_error(PREVIEW_ERROR_METAFILE_INIT_FAILED);
1845     LOG(ERROR) << "PdfMetafileSkia Init failed";
1846     return false;
1847   }
1848
1849   current_page_index_ = 0;
1850   pages_to_render_ = pages;
1851   // Sort and make unique.
1852   std::sort(pages_to_render_.begin(), pages_to_render_.end());
1853   pages_to_render_.resize(std::unique(pages_to_render_.begin(),
1854                                       pages_to_render_.end()) -
1855                           pages_to_render_.begin());
1856   // Remove invalid pages.
1857   pages_to_render_.resize(std::lower_bound(pages_to_render_.begin(),
1858                                            pages_to_render_.end(),
1859                                            total_page_count_) -
1860                           pages_to_render_.begin());
1861   print_ready_metafile_page_count_ = pages_to_render_.size();
1862   if (pages_to_render_.empty()) {
1863     print_ready_metafile_page_count_ = total_page_count_;
1864     // Render all pages.
1865     for (int i = 0; i < total_page_count_; ++i)
1866       pages_to_render_.push_back(i);
1867   } else if (generate_draft_pages_) {
1868     int pages_index = 0;
1869     for (int i = 0; i < total_page_count_; ++i) {
1870       if (pages_index < print_ready_metafile_page_count_ &&
1871           i == pages_to_render_[pages_index]) {
1872         pages_index++;
1873         continue;
1874       }
1875       pages_to_render_.push_back(i);
1876     }
1877   }
1878
1879   document_render_time_ = base::TimeDelta();
1880   begin_time_ = base::TimeTicks::Now();
1881
1882   return true;
1883 }
1884
1885 void PrintWebViewHelper::PrintPreviewContext::RenderedPreviewPage(
1886     const base::TimeDelta& page_time) {
1887   DCHECK_EQ(RENDERING, state_);
1888   document_render_time_ += page_time;
1889   UMA_HISTOGRAM_TIMES("PrintPreview.RenderPDFPageTime", page_time);
1890 }
1891
1892 void PrintWebViewHelper::PrintPreviewContext::AllPagesRendered() {
1893   DCHECK_EQ(RENDERING, state_);
1894   state_ = DONE;
1895   prep_frame_view_->FinishPrinting();
1896 }
1897
1898 void PrintWebViewHelper::PrintPreviewContext::FinalizePrintReadyDocument() {
1899   DCHECK(IsRendering());
1900
1901   base::TimeTicks begin_time = base::TimeTicks::Now();
1902   metafile_->FinishDocument();
1903
1904   if (print_ready_metafile_page_count_ <= 0) {
1905     NOTREACHED();
1906     return;
1907   }
1908
1909   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderToPDFTime",
1910                              document_render_time_);
1911   base::TimeDelta total_time = (base::TimeTicks::Now() - begin_time) +
1912                                document_render_time_;
1913   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderAndGeneratePDFTime",
1914                              total_time);
1915   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderAndGeneratePDFTimeAvgPerPage",
1916                              total_time / pages_to_render_.size());
1917 }
1918
1919 void PrintWebViewHelper::PrintPreviewContext::Finished() {
1920   DCHECK_EQ(DONE, state_);
1921   state_ = INITIALIZED;
1922   ClearContext();
1923 }
1924
1925 void PrintWebViewHelper::PrintPreviewContext::Failed(bool report_error) {
1926   DCHECK(state_ == INITIALIZED || state_ == RENDERING);
1927   state_ = INITIALIZED;
1928   if (report_error) {
1929     DCHECK_NE(PREVIEW_ERROR_NONE, error_);
1930     UMA_HISTOGRAM_ENUMERATION("PrintPreview.RendererError", error_,
1931                               PREVIEW_ERROR_LAST_ENUM);
1932   }
1933   ClearContext();
1934 }
1935
1936 int PrintWebViewHelper::PrintPreviewContext::GetNextPageNumber() {
1937   DCHECK_EQ(RENDERING, state_);
1938   if (IsFinalPageRendered())
1939     return -1;
1940   return pages_to_render_[current_page_index_++];
1941 }
1942
1943 bool PrintWebViewHelper::PrintPreviewContext::IsRendering() const {
1944   return state_ == RENDERING || state_ == DONE;
1945 }
1946
1947 bool PrintWebViewHelper::PrintPreviewContext::IsModifiable() {
1948   // The only kind of node we can print right now is a PDF node.
1949   return !PrintingNodeOrPdfFrame(source_frame(), source_node_);
1950 }
1951
1952 bool PrintWebViewHelper::PrintPreviewContext::HasSelection() {
1953   return IsModifiable() && source_frame()->hasSelection();
1954 }
1955
1956 bool PrintWebViewHelper::PrintPreviewContext::IsLastPageOfPrintReadyMetafile()
1957     const {
1958   DCHECK(IsRendering());
1959   return current_page_index_ == print_ready_metafile_page_count_;
1960 }
1961
1962 bool  PrintWebViewHelper::PrintPreviewContext::IsFinalPageRendered() const {
1963   DCHECK(IsRendering());
1964   return static_cast<size_t>(current_page_index_) == pages_to_render_.size();
1965 }
1966
1967 void PrintWebViewHelper::PrintPreviewContext::set_generate_draft_pages(
1968     bool generate_draft_pages) {
1969   DCHECK_EQ(INITIALIZED, state_);
1970   generate_draft_pages_ = generate_draft_pages;
1971 }
1972
1973 void PrintWebViewHelper::PrintPreviewContext::set_error(
1974     enum PrintPreviewErrorBuckets error) {
1975   error_ = error;
1976 }
1977
1978 blink::WebLocalFrame* PrintWebViewHelper::PrintPreviewContext::source_frame() {
1979   DCHECK_NE(UNINITIALIZED, state_);
1980   return source_frame_.GetFrame();
1981 }
1982
1983 const blink::WebNode&
1984     PrintWebViewHelper::PrintPreviewContext::source_node() const {
1985   DCHECK_NE(UNINITIALIZED, state_);
1986   return source_node_;
1987 }
1988
1989 blink::WebLocalFrame*
1990 PrintWebViewHelper::PrintPreviewContext::prepared_frame() {
1991   DCHECK_NE(UNINITIALIZED, state_);
1992   return prep_frame_view_->frame();
1993 }
1994
1995 const blink::WebNode&
1996     PrintWebViewHelper::PrintPreviewContext::prepared_node() const {
1997   DCHECK_NE(UNINITIALIZED, state_);
1998   return prep_frame_view_->node();
1999 }
2000
2001 int PrintWebViewHelper::PrintPreviewContext::total_page_count() const {
2002   DCHECK_NE(UNINITIALIZED, state_);
2003   return total_page_count_;
2004 }
2005
2006 bool PrintWebViewHelper::PrintPreviewContext::generate_draft_pages() const {
2007   return generate_draft_pages_;
2008 }
2009
2010 PdfMetafileSkia* PrintWebViewHelper::PrintPreviewContext::metafile() {
2011   DCHECK(IsRendering());
2012   return metafile_.get();
2013 }
2014
2015 int PrintWebViewHelper::PrintPreviewContext::last_error() const {
2016   return error_;
2017 }
2018
2019 gfx::Size PrintWebViewHelper::PrintPreviewContext::GetPrintCanvasSize() const {
2020   DCHECK(IsRendering());
2021   return prep_frame_view_->GetPrintCanvasSize();
2022 }
2023
2024 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
2025   prep_frame_view_.reset();
2026   metafile_.reset();
2027   pages_to_render_.clear();
2028   error_ = PREVIEW_ERROR_NONE;
2029 }
2030
2031 }  // namespace printing