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   virtual blink::WebFrame* createChildFrame(
 545       blink::WebLocalFrame* parent,
 546       const blink::WebString& name,
 547       blink::WebSandboxFlags sandboxFlags);
 548   virtual void frameDetached(blink::WebFrame* frame);
 549
 550  private:
 551   void CallOnReady();
 552   void ResizeForPrinting();
 553   void RestoreSize();
 554   void CopySelection(const WebPreferences& preferences);
 555
 556   FrameReference frame_;
 557   blink::WebNode node_to_print_;
 558   bool owns_web_view_;
 559   blink::WebPrintParams web_print_params_;
 560   gfx::Size prev_view_size_;
 561   gfx::Size prev_scroll_offset_;
 562   int expected_pages_count_;
 563   base::Closure on_ready_;
 564   bool should_print_backgrounds_;
 565   bool should_print_selection_only_;
 566   bool is_printing_started_;
 567
 568   base::WeakPtrFactory<PrepareFrameAndViewForPrint> weak_ptr_factory_;
 569
 570   DISALLOW_COPY_AND_ASSIGN(PrepareFrameAndViewForPrint);
 571 };
 572
 573 PrepareFrameAndViewForPrint::PrepareFrameAndViewForPrint(
 574     const PrintMsg_Print_Params& params,
 575     blink::WebLocalFrame* frame,
 576     const blink::WebNode& node,
 577     bool ignore_css_margins)
 578     : frame_(frame),
 579       node_to_print_(node),
 580       owns_web_view_(false),
 581       expected_pages_count_(0),
 582       should_print_backgrounds_(params.should_print_backgrounds),
 583       should_print_selection_only_(params.selection_only),
 584       is_printing_started_(false),
 585       weak_ptr_factory_(this) {
 586   PrintMsg_Print_Params print_params = params;
 587   if (!should_print_selection_only_ ||
 588       !PrintingNodeOrPdfFrame(frame, node_to_print_)) {
 589     bool fit_to_page = ignore_css_margins &&
 590                        print_params.print_scaling_option ==
 591                             blink::WebPrintScalingOptionFitToPrintableArea;
 592     ComputeWebKitPrintParamsInDesiredDpi(params, &web_print_params_);
 593     frame->printBegin(web_print_params_, node_to_print_);
 594     print_params = CalculatePrintParamsForCss(frame, 0, print_params,
 595                                               ignore_css_margins, fit_to_page,
 596                                               NULL);
 597     frame->printEnd();
 598   }
 599   ComputeWebKitPrintParamsInDesiredDpi(print_params, &web_print_params_);
 600 }
 601
 602 PrepareFrameAndViewForPrint::~PrepareFrameAndViewForPrint() {
 603   FinishPrinting();
 604 }
 605
 606 void PrepareFrameAndViewForPrint::ResizeForPrinting() {
 607   // Layout page according to printer page size. Since WebKit shrinks the
 608   // size of the page automatically (from 125% to 200%) we trick it to
 609   // think the page is 125% larger so the size of the page is correct for
 610   // minimum (default) scaling.
 611   // This is important for sites that try to fill the page.
 612   gfx::Size print_layout_size(web_print_params_.printContentArea.width,
 613                               web_print_params_.printContentArea.height);
 614   print_layout_size.set_height(
 615       static_cast<int>(static_cast<double>(print_layout_size.height()) * 1.25));
 616
 617   if (!frame())
 618     return;
 619   blink::WebView* web_view = frame_.view();
 620   // Backup size and offset.
 621   if (blink::WebFrame* web_frame = web_view->mainFrame())
 622     prev_scroll_offset_ = web_frame->scrollOffset();
 623   prev_view_size_ = web_view->size();
 624
 625   web_view->resize(print_layout_size);
 626 }
 627
 628
 629 void PrepareFrameAndViewForPrint::StartPrinting() {
 630   ResizeForPrinting();
 631   blink::WebView* web_view = frame_.view();
 632   web_view->settings()->setShouldPrintBackgrounds(should_print_backgrounds_);
 633   expected_pages_count_ =
 634       frame()->printBegin(web_print_params_, node_to_print_);
 635   is_printing_started_ = true;
 636 }
 637
 638 void PrepareFrameAndViewForPrint::CopySelectionIfNeeded(
 639     const WebPreferences& preferences,
 640     const base::Closure& on_ready) {
 641   on_ready_ = on_ready;
 642   if (should_print_selection_only_)
 643     CopySelection(preferences);
 644   else
 645     didStopLoading();
 646 }
 647
 648 void PrepareFrameAndViewForPrint::CopySelection(
 649     const WebPreferences& preferences) {
 650   ResizeForPrinting();
 651   std::string url_str = "data:text/html;charset=utf-8,";
 652   url_str.append(
 653       net::EscapeQueryParamValue(frame()->selectionAsMarkup().utf8(), false));
 654   RestoreSize();
 655   // Create a new WebView with the same settings as the current display one.
 656   // Except that we disable javascript (don't want any active content running
 657   // on the page).
 658   WebPreferences prefs = preferences;
 659   prefs.javascript_enabled = false;
 660   prefs.java_enabled = false;
 661
 662   blink::WebView* web_view = blink::WebView::create(this);
 663   owns_web_view_ = true;
 664   content::RenderView::ApplyWebPreferences(prefs, web_view);
 665   web_view->setMainFrame(blink::WebLocalFrame::create(this));
 666   frame_.Reset(web_view->mainFrame()->toWebLocalFrame());
 667   node_to_print_.reset();
 668
 669   // When loading is done this will call didStopLoading() and that will do the
 670   // actual printing.
 671   frame()->loadRequest(blink::WebURLRequest(GURL(url_str)));
 672 }
 673
 674 bool PrepareFrameAndViewForPrint::allowsBrokenNullLayerTreeView() const {
 675   return true;
 676 }
 677
 678 void PrepareFrameAndViewForPrint::didStopLoading() {
 679   DCHECK(!on_ready_.is_null());
 680   // Don't call callback here, because it can delete |this| and WebView that is
 681   // called didStopLoading.
 682   base::MessageLoop::current()->PostTask(
 683       FROM_HERE,
 684       base::Bind(&PrepareFrameAndViewForPrint::CallOnReady,
 685                  weak_ptr_factory_.GetWeakPtr()));
 686 }
 687
 688 blink::WebFrame* PrepareFrameAndViewForPrint::createChildFrame(
 689     blink::WebLocalFrame* parent,
 690     const blink::WebString& name,
 691     blink::WebSandboxFlags sandboxFlags) {
 692   blink::WebFrame* frame = blink::WebLocalFrame::create(this);
 693   parent->appendChild(frame);
 694   return frame;
 695 }
 696
 697 void PrepareFrameAndViewForPrint::frameDetached(blink::WebFrame* frame) {
 698   if (frame->parent())
 699     frame->parent()->removeChild(frame);
 700   frame->close();
 701 }
 702
 703 void PrepareFrameAndViewForPrint::CallOnReady() {
 704   return on_ready_.Run();  // Can delete |this|.
 705 }
 706
 707 gfx::Size PrepareFrameAndViewForPrint::GetPrintCanvasSize() const {
 708   DCHECK(is_printing_started_);
 709   return gfx::Size(web_print_params_.printContentArea.width,
 710                    web_print_params_.printContentArea.height);
 711 }
 712
 713 void PrepareFrameAndViewForPrint::RestoreSize() {
 714   if (frame()) {
 715     blink::WebView* web_view = frame_.GetFrame()->view();
 716     web_view->resize(prev_view_size_);
 717     if (blink::WebFrame* web_frame = web_view->mainFrame())
 718       web_frame->setScrollOffset(prev_scroll_offset_);
 719   }
 720 }
 721
 722 void PrepareFrameAndViewForPrint::FinishPrinting() {
 723   blink::WebLocalFrame* frame = frame_.GetFrame();
 724   if (frame) {
 725     blink::WebView* web_view = frame->view();
 726     if (is_printing_started_) {
 727       is_printing_started_ = false;
 728       frame->printEnd();
 729       if (!owns_web_view_) {
 730         web_view->settings()->setShouldPrintBackgrounds(false);
 731         RestoreSize();
 732       }
 733     }
 734     if (owns_web_view_) {
 735       DCHECK(!frame->isLoading());
 736       owns_web_view_ = false;
 737       web_view->close();
 738     }
 739   }
 740   frame_.Reset(NULL);
 741   on_ready_.Reset();
 742 }
 743
 744 PrintWebViewHelper::PrintWebViewHelper(content::RenderView* render_view)
 745     : content::RenderViewObserver(render_view),
 746       content::RenderViewObserverTracker<PrintWebViewHelper>(render_view),
 747       reset_prep_frame_view_(false),
 748       is_preview_enabled_(IsPrintPreviewEnabled()),
 749       is_scripted_print_throttling_disabled_(IsPrintThrottlingDisabled()),
 750       is_print_ready_metafile_sent_(false),
 751       ignore_css_margins_(false),
 752       user_cancelled_scripted_print_count_(0),
 753       is_scripted_printing_blocked_(false),
 754       notify_browser_of_print_failure_(true),
 755       print_for_preview_(false),
 756       print_node_in_progress_(false),
 757       is_loading_(false),
 758       is_scripted_preview_delayed_(false),
 759       weak_ptr_factory_(this) {
 760   // TODO(sgurun) enable window.print() for webview crbug.com/322303
 761   SetScriptedPrintBlocked(true);
 762 }
 763
 764 PrintWebViewHelper::~PrintWebViewHelper() {}
 765
 766 bool PrintWebViewHelper::IsScriptInitiatedPrintAllowed(
 767     blink::WebFrame* frame, bool user_initiated) {
 768 #if defined(OS_ANDROID)
 769   return false;
 770 #endif  // defined(OS_ANDROID)
 771   if (is_scripted_printing_blocked_)
 772     return false;
 773   // If preview is enabled, then the print dialog is tab modal, and the user
 774   // can always close the tab on a mis-behaving page (the system print dialog
 775   // is app modal). If the print was initiated through user action, don't
 776   // throttle. Or, if the command line flag to skip throttling has been set.
 777   if (!is_scripted_print_throttling_disabled_ &&
 778       !is_preview_enabled_ &&
 779       !user_initiated)
 780     return !IsScriptInitiatedPrintTooFrequent(frame);
 781   return true;
 782 }
 783
 784 void PrintWebViewHelper::DidStartLoading() {
 785   is_loading_ = true;
 786 }
 787
 788 void PrintWebViewHelper::DidStopLoading() {
 789   is_loading_ = false;
 790   ShowScriptedPrintPreview();
 791 }
 792
 793 // Prints |frame| which called window.print().
 794 void PrintWebViewHelper::PrintPage(blink::WebLocalFrame* frame,
 795                                    bool user_initiated) {
 796   DCHECK(frame);
 797
 798 #if !defined(OS_ANDROID)
 799   // TODO(sgurun) android_webview hack
 800   // Allow Prerendering to cancel this print request if necessary.
 801   if (prerender::PrerenderHelper::IsPrerendering(render_view())) {
 802     Send(new ChromeViewHostMsg_CancelPrerenderForPrinting(routing_id()));
 803     return;
 804   }
 805 #endif  // !defined(OS_ANDROID)
 806
 807   if (!IsScriptInitiatedPrintAllowed(frame, user_initiated))
 808     return;
 809   IncrementScriptedPrintCount();
 810
 811   if (is_preview_enabled_) {
 812     print_preview_context_.InitWithFrame(frame);
 813     RequestPrintPreview(PRINT_PREVIEW_SCRIPTED);
 814   } else {
 815     Print(frame, blink::WebNode());
 816   }
 817 }
 818
 819 bool PrintWebViewHelper::OnMessageReceived(const IPC::Message& message) {
 820   bool handled = true;
 821   IPC_BEGIN_MESSAGE_MAP(PrintWebViewHelper, message)
 822     IPC_MESSAGE_HANDLER(PrintMsg_PrintPages, OnPrintPages)
 823     IPC_MESSAGE_HANDLER(PrintMsg_PrintForSystemDialog, OnPrintForSystemDialog)
 824     IPC_MESSAGE_HANDLER(PrintMsg_InitiatePrintPreview, OnInitiatePrintPreview)
 825     IPC_MESSAGE_HANDLER(PrintMsg_PrintPreview, OnPrintPreview)
 826     IPC_MESSAGE_HANDLER(PrintMsg_PrintForPrintPreview, OnPrintForPrintPreview)
 827     IPC_MESSAGE_HANDLER(PrintMsg_PrintingDone, OnPrintingDone)
 828     IPC_MESSAGE_HANDLER(PrintMsg_ResetScriptedPrintCount,
 829                         ResetScriptedPrintCount)
 830     IPC_MESSAGE_HANDLER(PrintMsg_SetScriptedPrintingBlocked,
 831                         SetScriptedPrintBlocked)
 832     IPC_MESSAGE_UNHANDLED(handled = false)
 833     IPC_END_MESSAGE_MAP()
 834   return handled;
 835 }
 836
 837 void PrintWebViewHelper::OnPrintForPrintPreview(
 838     const base::DictionaryValue& job_settings) {
 839   DCHECK(is_preview_enabled_);
 840   // If still not finished with earlier print request simply ignore.
 841   if (prep_frame_view_)
 842     return;
 843
 844   if (!render_view()->GetWebView())
 845     return;
 846   blink::WebFrame* main_frame = render_view()->GetWebView()->mainFrame();
 847   if (!main_frame)
 848     return;
 849
 850   blink::WebDocument document = main_frame->document();
 851   // <object> with id="pdf-viewer" is created in
 852   // chrome/browser/resources/print_preview/print_preview.js
 853   blink::WebElement pdf_element = document.getElementById("pdf-viewer");
 854   if (pdf_element.isNull()) {
 855     NOTREACHED();
 856     return;
 857   }
 858
 859   // Set |print_for_preview_| flag and autoreset it to back to original
 860   // on return.
 861   base::AutoReset<bool> set_printing_flag(&print_for_preview_, true);
 862
 863   blink::WebLocalFrame* pdf_frame = pdf_element.document().frame();
 864   if (!UpdatePrintSettings(pdf_frame, pdf_element, job_settings)) {
 865     LOG(ERROR) << "UpdatePrintSettings failed";
 866     DidFinishPrinting(FAIL_PRINT);
 867     return;
 868   }
 869
 870   // Print page onto entire page not just printable area. Preview PDF already
 871   // has content in correct position taking into account page size and printable
 872   // area.
 873   // TODO(vitalybuka) : Make this consistent on all platform. This change
 874   // affects Windows only. On Linux and OSX RenderPagesForPrint does not use
 875   // printable_area. Also we can't change printable_area deeper inside
 876   // RenderPagesForPrint for Windows, because it's used also by native
 877   // printing and it expects real printable_area value.
 878   // See http://crbug.com/123408
 879   PrintMsg_Print_Params& print_params = print_pages_params_->params;
 880   print_params.printable_area = gfx::Rect(print_params.page_size);
 881
 882   // Render Pages for printing.
 883   if (!RenderPagesForPrint(pdf_frame, pdf_element)) {
 884     LOG(ERROR) << "RenderPagesForPrint failed";
 885     DidFinishPrinting(FAIL_PRINT);
 886   }
 887 }
 888
 889 bool PrintWebViewHelper::GetPrintFrame(blink::WebLocalFrame** frame) {
 890   DCHECK(frame);
 891   blink::WebView* webView = render_view()->GetWebView();
 892   DCHECK(webView);
 893   if (!webView)
 894     return false;
 895
 896   // If the user has selected text in the currently focused frame we print
 897   // only that frame (this makes print selection work for multiple frames).
 898   blink::WebLocalFrame* focusedFrame =
 899       webView->focusedFrame()->toWebLocalFrame();
 900   *frame = focusedFrame->hasSelection()
 901                ? focusedFrame
 902                : webView->mainFrame()->toWebLocalFrame();
 903   return true;
 904 }
 905
 906 void PrintWebViewHelper::OnPrintPages() {
 907   blink::WebLocalFrame* frame;
 908   if (GetPrintFrame(&frame))
 909     Print(frame, blink::WebNode());
 910 }
 911
 912 void PrintWebViewHelper::OnPrintForSystemDialog() {
 913   blink::WebLocalFrame* frame = print_preview_context_.source_frame();
 914   if (!frame) {
 915     NOTREACHED();
 916     return;
 917   }
 918
 919   Print(frame, print_preview_context_.source_node());
 920 }
 921
 922 void PrintWebViewHelper::GetPageSizeAndContentAreaFromPageLayout(
 923     const PageSizeMargins& page_layout_in_points,
 924     gfx::Size* page_size,
 925     gfx::Rect* content_area) {
 926   *page_size = gfx::Size(
 927       page_layout_in_points.content_width +
 928           page_layout_in_points.margin_right +
 929           page_layout_in_points.margin_left,
 930       page_layout_in_points.content_height +
 931           page_layout_in_points.margin_top +
 932           page_layout_in_points.margin_bottom);
 933   *content_area = gfx::Rect(page_layout_in_points.margin_left,
 934                             page_layout_in_points.margin_top,
 935                             page_layout_in_points.content_width,
 936                             page_layout_in_points.content_height);
 937 }
 938
 939 void PrintWebViewHelper::UpdateFrameMarginsCssInfo(
 940     const base::DictionaryValue& settings) {
 941   int margins_type = 0;
 942   if (!settings.GetInteger(kSettingMarginsType, &margins_type))
 943     margins_type = DEFAULT_MARGINS;
 944   ignore_css_margins_ = (margins_type != DEFAULT_MARGINS);
 945 }
 946
 947 bool PrintWebViewHelper::IsPrintToPdfRequested(
 948     const base::DictionaryValue& job_settings) {
 949   bool print_to_pdf = false;
 950   if (!job_settings.GetBoolean(kSettingPrintToPDF, &print_to_pdf))
 951     NOTREACHED();
 952   return print_to_pdf;
 953 }
 954
 955 blink::WebPrintScalingOption PrintWebViewHelper::GetPrintScalingOption(
 956     bool source_is_html, const base::DictionaryValue& job_settings,
 957     const PrintMsg_Print_Params& params) {
 958   DCHECK(!print_for_preview_);
 959
 960   if (params.print_to_pdf)
 961     return blink::WebPrintScalingOptionSourceSize;
 962
 963   if (!source_is_html) {
 964     if (!FitToPageEnabled(job_settings))
 965       return blink::WebPrintScalingOptionNone;
 966
 967     bool no_plugin_scaling =
 968         print_preview_context_.source_frame()->isPrintScalingDisabledForPlugin(
 969             print_preview_context_.source_node());
 970
 971     if (params.is_first_request && no_plugin_scaling)
 972       return blink::WebPrintScalingOptionNone;
 973   }
 974   return blink::WebPrintScalingOptionFitToPrintableArea;
 975 }
 976
 977 void PrintWebViewHelper::OnPrintPreview(const base::DictionaryValue& settings) {
 978   DCHECK(is_preview_enabled_);
 979   print_preview_context_.OnPrintPreview();
 980
 981   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
 982                             PREVIEW_EVENT_REQUESTED, PREVIEW_EVENT_MAX);
 983
 984   if (!UpdatePrintSettings(print_preview_context_.source_frame(),
 985                            print_preview_context_.source_node(), settings)) {
 986     if (print_preview_context_.last_error() != PREVIEW_ERROR_BAD_SETTING) {
 987       Send(new PrintHostMsg_PrintPreviewInvalidPrinterSettings(
 988           routing_id(), print_pages_params_->params.document_cookie));
 989       notify_browser_of_print_failure_ = false;  // Already sent.
 990     }
 991     DidFinishPrinting(FAIL_PREVIEW);
 992     return;
 993   }
 994
 995   // If we are previewing a pdf and the print scaling is disabled, send a
 996   // message to browser.
 997   if (print_pages_params_->params.is_first_request &&
 998       !print_preview_context_.IsModifiable() &&
 999       print_preview_context_.source_frame()->isPrintScalingDisabledForPlugin(
1000           print_preview_context_.source_node())) {
1001     Send(new PrintHostMsg_PrintPreviewScalingDisabled(routing_id()));
1002   }
1003
1004   is_print_ready_metafile_sent_ = false;
1005
1006   // PDF printer device supports alpha blending.
1007   print_pages_params_->params.supports_alpha_blend = true;
1008
1009   bool generate_draft_pages = false;
1010   if (!settings.GetBoolean(kSettingGenerateDraftData,
1011                            &generate_draft_pages)) {
1012     NOTREACHED();
1013   }
1014   print_preview_context_.set_generate_draft_pages(generate_draft_pages);
1015
1016   PrepareFrameForPreviewDocument();
1017 }
1018
1019 void PrintWebViewHelper::PrepareFrameForPreviewDocument() {
1020   reset_prep_frame_view_ = false;
1021
1022   if (!print_pages_params_ || CheckForCancel()) {
1023     DidFinishPrinting(FAIL_PREVIEW);
1024     return;
1025   }
1026
1027   // Don't reset loading frame or WebKit will fail assert. Just retry when
1028   // current selection is loaded.
1029   if (prep_frame_view_ && prep_frame_view_->IsLoadingSelection()) {
1030     reset_prep_frame_view_ = true;
1031     return;
1032   }
1033
1034   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1035   prep_frame_view_.reset(
1036       new PrepareFrameAndViewForPrint(print_params,
1037                                       print_preview_context_.source_frame(),
1038                                       print_preview_context_.source_node(),
1039                                       ignore_css_margins_));
1040   prep_frame_view_->CopySelectionIfNeeded(
1041       render_view()->GetWebkitPreferences(),
1042       base::Bind(&PrintWebViewHelper::OnFramePreparedForPreviewDocument,
1043                  base::Unretained(this)));
1044 }
1045
1046 void PrintWebViewHelper::OnFramePreparedForPreviewDocument() {
1047   if (reset_prep_frame_view_) {
1048     PrepareFrameForPreviewDocument();
1049     return;
1050   }
1051   DidFinishPrinting(CreatePreviewDocument() ? OK : FAIL_PREVIEW);
1052 }
1053
1054 bool PrintWebViewHelper::CreatePreviewDocument() {
1055   if (!print_pages_params_ || CheckForCancel())
1056     return false;
1057
1058   UMA_HISTOGRAM_ENUMERATION("PrintPreview.PreviewEvent",
1059                             PREVIEW_EVENT_CREATE_DOCUMENT, PREVIEW_EVENT_MAX);
1060
1061   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1062   const std::vector<int>& pages = print_pages_params_->pages;
1063
1064   if (!print_preview_context_.CreatePreviewDocument(prep_frame_view_.release(),
1065                                                     pages)) {
1066     return false;
1067   }
1068
1069   PageSizeMargins default_page_layout;
1070   ComputePageLayoutInPointsForCss(print_preview_context_.prepared_frame(), 0,
1071                                   print_params, ignore_css_margins_, NULL,
1072                                   &default_page_layout);
1073
1074   bool has_page_size_style = PrintingFrameHasPageSizeStyle(
1075       print_preview_context_.prepared_frame(),
1076       print_preview_context_.total_page_count());
1077   int dpi = GetDPI(&print_params);
1078
1079   gfx::Rect printable_area_in_points(
1080       ConvertUnit(print_params.printable_area.x(), dpi, kPointsPerInch),
1081       ConvertUnit(print_params.printable_area.y(), dpi, kPointsPerInch),
1082       ConvertUnit(print_params.printable_area.width(), dpi, kPointsPerInch),
1083       ConvertUnit(print_params.printable_area.height(), dpi, kPointsPerInch));
1084
1085   // Margins: Send default page layout to browser process.
1086   Send(new PrintHostMsg_DidGetDefaultPageLayout(routing_id(),
1087                                                 default_page_layout,
1088                                                 printable_area_in_points,
1089                                                 has_page_size_style));
1090
1091   PrintHostMsg_DidGetPreviewPageCount_Params params;
1092   params.page_count = print_preview_context_.total_page_count();
1093   params.is_modifiable = print_preview_context_.IsModifiable();
1094   params.document_cookie = print_params.document_cookie;
1095   params.preview_request_id = print_params.preview_request_id;
1096   params.clear_preview_data = print_preview_context_.generate_draft_pages();
1097   Send(new PrintHostMsg_DidGetPreviewPageCount(routing_id(), params));
1098   if (CheckForCancel())
1099     return false;
1100
1101   while (!print_preview_context_.IsFinalPageRendered()) {
1102     int page_number = print_preview_context_.GetNextPageNumber();
1103     DCHECK_GE(page_number, 0);
1104     if (!RenderPreviewPage(page_number, print_params))
1105       return false;
1106
1107     if (CheckForCancel())
1108       return false;
1109
1110     // We must call PrepareFrameAndViewForPrint::FinishPrinting() (by way of
1111     // print_preview_context_.AllPagesRendered()) before calling
1112     // FinalizePrintReadyDocument() when printing a PDF because the plugin
1113     // code does not generate output until we call FinishPrinting().  We do not
1114     // generate draft pages for PDFs, so IsFinalPageRendered() and
1115     // IsLastPageOfPrintReadyMetafile() will be true in the same iteration of
1116     // the loop.
1117     if (print_preview_context_.IsFinalPageRendered())
1118       print_preview_context_.AllPagesRendered();
1119
1120     if (print_preview_context_.IsLastPageOfPrintReadyMetafile()) {
1121       DCHECK(print_preview_context_.IsModifiable() ||
1122              print_preview_context_.IsFinalPageRendered());
1123       if (!FinalizePrintReadyDocument())
1124         return false;
1125     }
1126   }
1127   print_preview_context_.Finished();
1128   return true;
1129 }
1130
1131 bool PrintWebViewHelper::FinalizePrintReadyDocument() {
1132   DCHECK(!is_print_ready_metafile_sent_);
1133   print_preview_context_.FinalizePrintReadyDocument();
1134
1135   // Get the size of the resulting metafile.
1136   PdfMetafileSkia* metafile = print_preview_context_.metafile();
1137   uint32 buf_size = metafile->GetDataSize();
1138   DCHECK_GT(buf_size, 0u);
1139
1140   PrintHostMsg_DidPreviewDocument_Params preview_params;
1141   preview_params.reuse_existing_data = false;
1142   preview_params.data_size = buf_size;
1143   preview_params.document_cookie = print_pages_params_->params.document_cookie;
1144   preview_params.expected_pages_count =
1145       print_preview_context_.total_page_count();
1146   preview_params.modifiable = print_preview_context_.IsModifiable();
1147   preview_params.preview_request_id =
1148       print_pages_params_->params.preview_request_id;
1149
1150   // Ask the browser to create the shared memory for us.
1151   if (!CopyMetafileDataToSharedMem(metafile,
1152                                    &(preview_params.metafile_data_handle))) {
1153     LOG(ERROR) << "CopyMetafileDataToSharedMem failed";
1154     print_preview_context_.set_error(PREVIEW_ERROR_METAFILE_COPY_FAILED);
1155     return false;
1156   }
1157   is_print_ready_metafile_sent_ = true;
1158
1159   Send(new PrintHostMsg_MetafileReadyForPrinting(routing_id(), preview_params));
1160   return true;
1161 }
1162
1163 void PrintWebViewHelper::OnPrintingDone(bool success) {
1164   notify_browser_of_print_failure_ = false;
1165   if (!success)
1166     LOG(ERROR) << "Failure in OnPrintingDone";
1167   DidFinishPrinting(success ? OK : FAIL_PRINT);
1168 }
1169
1170 void PrintWebViewHelper::SetScriptedPrintBlocked(bool blocked) {
1171   is_scripted_printing_blocked_ = blocked;
1172 }
1173
1174 void PrintWebViewHelper::OnInitiatePrintPreview(bool selection_only) {
1175   DCHECK(is_preview_enabled_);
1176   blink::WebLocalFrame* frame = NULL;
1177   GetPrintFrame(&frame);
1178   DCHECK(frame);
1179   print_preview_context_.InitWithFrame(frame);
1180   RequestPrintPreview(selection_only ?
1181                       PRINT_PREVIEW_USER_INITIATED_SELECTION :
1182                       PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME);
1183 }
1184
1185 bool PrintWebViewHelper::IsPrintingEnabled() {
1186   bool result = false;
1187   Send(new PrintHostMsg_IsPrintingEnabled(routing_id(), &result));
1188   return result;
1189 }
1190
1191 void PrintWebViewHelper::PrintNode(const blink::WebNode& node) {
1192   if (node.isNull() || !node.document().frame()) {
1193     // This can occur when the context menu refers to an invalid WebNode.
1194     // See http://crbug.com/100890#c17 for a repro case.
1195     return;
1196   }
1197
1198   if (print_node_in_progress_) {
1199     // This can happen as a result of processing sync messages when printing
1200     // from ppapi plugins. It's a rare case, so its OK to just fail here.
1201     // See http://crbug.com/159165.
1202     return;
1203   }
1204
1205   print_node_in_progress_ = true;
1206
1207   // Make a copy of the node, in case RenderView::OnContextMenuClosed resets
1208   // its |context_menu_node_|.
1209   if (is_preview_enabled_) {
1210     print_preview_context_.InitWithNode(node);
1211     RequestPrintPreview(PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE);
1212   } else {
1213     blink::WebNode duplicate_node(node);
1214     Print(duplicate_node.document().frame(), duplicate_node);
1215   }
1216
1217   print_node_in_progress_ = false;
1218 }
1219
1220 void PrintWebViewHelper::Print(blink::WebLocalFrame* frame,
1221                                const blink::WebNode& node) {
1222   // If still not finished with earlier print request simply ignore.
1223   if (prep_frame_view_)
1224     return;
1225
1226   FrameReference frame_ref(frame);
1227
1228   int expected_page_count = 0;
1229   if (!CalculateNumberOfPages(frame, node, &expected_page_count)) {
1230     DidFinishPrinting(FAIL_PRINT_INIT);
1231     return;  // Failed to init print page settings.
1232   }
1233
1234   // Some full screen plugins can say they don't want to print.
1235   if (!expected_page_count) {
1236     DidFinishPrinting(FAIL_PRINT);
1237     return;
1238   }
1239
1240 #if !defined(OS_ANDROID)
1241   // TODO(sgurun) android_webview hack
1242   // Ask the browser to show UI to retrieve the final print settings.
1243   if (!GetPrintSettingsFromUser(frame_ref.GetFrame(), node,
1244                                 expected_page_count)) {
1245     DidFinishPrinting(OK);  // Release resources and fail silently.
1246     return;
1247   }
1248 #endif  // !defined(OS_ANDROID)
1249
1250   // Render Pages for printing.
1251   if (!RenderPagesForPrint(frame_ref.GetFrame(), node)) {
1252     LOG(ERROR) << "RenderPagesForPrint failed";
1253     DidFinishPrinting(FAIL_PRINT);
1254   }
1255   ResetScriptedPrintCount();
1256 }
1257
1258 void PrintWebViewHelper::DidFinishPrinting(PrintingResult result) {
1259   switch (result) {
1260     case OK:
1261       break;
1262
1263     case FAIL_PRINT_INIT:
1264       DCHECK(!notify_browser_of_print_failure_);
1265       break;
1266
1267     case FAIL_PRINT:
1268       if (notify_browser_of_print_failure_ && print_pages_params_.get()) {
1269         int cookie = print_pages_params_->params.document_cookie;
1270         Send(new PrintHostMsg_PrintingFailed(routing_id(), cookie));
1271       }
1272       break;
1273
1274     case FAIL_PREVIEW:
1275       DCHECK(is_preview_enabled_);
1276       int cookie = print_pages_params_.get() ?
1277           print_pages_params_->params.document_cookie : 0;
1278       if (notify_browser_of_print_failure_) {
1279         LOG(ERROR) << "CreatePreviewDocument failed";
1280         Send(new PrintHostMsg_PrintPreviewFailed(routing_id(), cookie));
1281       } else {
1282         Send(new PrintHostMsg_PrintPreviewCancelled(routing_id(), cookie));
1283       }
1284       print_preview_context_.Failed(notify_browser_of_print_failure_);
1285       break;
1286   }
1287
1288   prep_frame_view_.reset();
1289   print_pages_params_.reset();
1290   notify_browser_of_print_failure_ = true;
1291 }
1292
1293 void PrintWebViewHelper::OnFramePreparedForPrintPages() {
1294   PrintPages();
1295   FinishFramePrinting();
1296 }
1297
1298 void PrintWebViewHelper::PrintPages() {
1299   if (!prep_frame_view_)  // Printing is already canceled or failed.
1300     return;
1301   prep_frame_view_->StartPrinting();
1302
1303   int page_count = prep_frame_view_->GetExpectedPageCount();
1304   if (!page_count) {
1305     LOG(ERROR) << "Can't print 0 pages.";
1306     return DidFinishPrinting(FAIL_PRINT);
1307   }
1308
1309   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1310   const PrintMsg_Print_Params& print_params = params.params;
1311
1312 #if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
1313   // TODO(vitalybuka): should be page_count or valid pages from params.pages.
1314   // See http://crbug.com/161576
1315   Send(new PrintHostMsg_DidGetPrintedPagesCount(routing_id(),
1316                                                 print_params.document_cookie,
1317                                                 page_count));
1318 #endif  // !defined(OS_CHROMEOS)
1319
1320   if (print_params.preview_ui_id < 0) {
1321     // Printing for system dialog.
1322     int printed_count = params.pages.empty() ? page_count : params.pages.size();
1323 #if !defined(OS_CHROMEOS)
1324     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.SystemDialog", printed_count);
1325 #else
1326     UMA_HISTOGRAM_COUNTS("PrintPreview.PageCount.PrintToCloudPrintWebDialog",
1327                          printed_count);
1328 #endif  // !defined(OS_CHROMEOS)
1329   }
1330
1331
1332   if (!PrintPagesNative(prep_frame_view_->frame(), page_count,
1333                         prep_frame_view_->GetPrintCanvasSize())) {
1334     LOG(ERROR) << "Printing failed.";
1335     return DidFinishPrinting(FAIL_PRINT);
1336   }
1337 }
1338
1339 void PrintWebViewHelper::FinishFramePrinting() {
1340   prep_frame_view_.reset();
1341 }
1342
1343 #if defined(OS_MACOSX) || defined(OS_WIN)
1344 bool PrintWebViewHelper::PrintPagesNative(blink::WebFrame* frame,
1345                                           int page_count,
1346                                           const gfx::Size& canvas_size) {
1347   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1348   const PrintMsg_Print_Params& print_params = params.params;
1349
1350   PrintMsg_PrintPage_Params page_params;
1351   page_params.params = print_params;
1352   if (params.pages.empty()) {
1353     for (int i = 0; i < page_count; ++i) {
1354       page_params.page_number = i;
1355       PrintPageInternal(page_params, canvas_size, frame);
1356     }
1357   } else {
1358     for (size_t i = 0; i < params.pages.size(); ++i) {
1359       if (params.pages[i] >= page_count)
1360         break;
1361       page_params.page_number = params.pages[i];
1362       PrintPageInternal(page_params, canvas_size, frame);
1363     }
1364   }
1365   return true;
1366 }
1367
1368 #endif  // OS_MACOSX || OS_WIN
1369
1370 // static - Not anonymous so that platform implementations can use it.
1371 void PrintWebViewHelper::ComputePageLayoutInPointsForCss(
1372     blink::WebFrame* frame,
1373     int page_index,
1374     const PrintMsg_Print_Params& page_params,
1375     bool ignore_css_margins,
1376     double* scale_factor,
1377     PageSizeMargins* page_layout_in_points) {
1378   PrintMsg_Print_Params params = CalculatePrintParamsForCss(
1379       frame, page_index, page_params, ignore_css_margins,
1380       page_params.print_scaling_option ==
1381           blink::WebPrintScalingOptionFitToPrintableArea,
1382       scale_factor);
1383   CalculatePageLayoutFromPrintParams(params, page_layout_in_points);
1384 }
1385
1386 bool PrintWebViewHelper::InitPrintSettings(bool fit_to_paper_size) {
1387   PrintMsg_PrintPages_Params settings;
1388   Send(new PrintHostMsg_GetDefaultPrintSettings(routing_id(),
1389                                                 &settings.params));
1390   // Check if the printer returned any settings, if the settings is empty, we
1391   // can safely assume there are no printer drivers configured. So we safely
1392   // terminate.
1393   bool result = true;
1394   if (!PrintMsg_Print_Params_IsValid(settings.params))
1395     result = false;
1396
1397   if (result &&
1398       (settings.params.dpi < kMinDpi || settings.params.document_cookie == 0)) {
1399     // Invalid print page settings.
1400     NOTREACHED();
1401     result = false;
1402   }
1403
1404   // Reset to default values.
1405   ignore_css_margins_ = false;
1406   settings.pages.clear();
1407
1408   settings.params.print_scaling_option =
1409       blink::WebPrintScalingOptionSourceSize;
1410   if (fit_to_paper_size) {
1411     settings.params.print_scaling_option =
1412         blink::WebPrintScalingOptionFitToPrintableArea;
1413   }
1414
1415   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1416   return result;
1417 }
1418
1419 bool PrintWebViewHelper::CalculateNumberOfPages(blink::WebLocalFrame* frame,
1420                                                 const blink::WebNode& node,
1421                                                 int* number_of_pages) {
1422   DCHECK(frame);
1423   bool fit_to_paper_size = !(PrintingNodeOrPdfFrame(frame, node));
1424   if (!InitPrintSettings(fit_to_paper_size)) {
1425     notify_browser_of_print_failure_ = false;
1426 #if !defined(OS_ANDROID)
1427     // TODO(sgurun) android_webview hack
1428     render_view()->RunModalAlertDialog(
1429         frame,
1430         l10n_util::GetStringUTF16(IDS_PRINT_INVALID_PRINTER_SETTINGS));
1431 #endif  //  !defined(OS_ANDROID)
1432     return false;
1433   }
1434
1435   const PrintMsg_Print_Params& params = print_pages_params_->params;
1436   PrepareFrameAndViewForPrint prepare(params, frame, node, ignore_css_margins_);
1437   prepare.StartPrinting();
1438
1439   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
1440                                              params.document_cookie));
1441   *number_of_pages = prepare.GetExpectedPageCount();
1442   return true;
1443 }
1444
1445 bool PrintWebViewHelper::UpdatePrintSettings(
1446     blink::WebLocalFrame* frame,
1447     const blink::WebNode& node,
1448     const base::DictionaryValue& passed_job_settings) {
1449   DCHECK(is_preview_enabled_);
1450   const base::DictionaryValue* job_settings = &passed_job_settings;
1451   base::DictionaryValue modified_job_settings;
1452   if (job_settings->empty()) {
1453     if (!print_for_preview_)
1454       print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1455     return false;
1456   }
1457
1458   bool source_is_html = true;
1459   if (print_for_preview_) {
1460     if (!job_settings->GetBoolean(kSettingPreviewModifiable, &source_is_html)) {
1461       NOTREACHED();
1462     }
1463   } else {
1464     source_is_html = !PrintingNodeOrPdfFrame(frame, node);
1465   }
1466
1467   if (print_for_preview_ || !source_is_html) {
1468     modified_job_settings.MergeDictionary(job_settings);
1469     modified_job_settings.SetBoolean(kSettingHeaderFooterEnabled, false);
1470     modified_job_settings.SetInteger(kSettingMarginsType, NO_MARGINS);
1471     job_settings = &modified_job_settings;
1472   }
1473
1474   // Send the cookie so that UpdatePrintSettings can reuse PrinterQuery when
1475   // possible.
1476   int cookie = print_pages_params_.get() ?
1477       print_pages_params_->params.document_cookie : 0;
1478   PrintMsg_PrintPages_Params settings;
1479   Send(new PrintHostMsg_UpdatePrintSettings(routing_id(), cookie, *job_settings,
1480                                             &settings));
1481   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1482
1483   if (!PrintMsg_Print_Params_IsValid(settings.params)) {
1484     if (!print_for_preview_) {
1485       print_preview_context_.set_error(PREVIEW_ERROR_INVALID_PRINTER_SETTINGS);
1486     } else {
1487 #if !defined(OS_ANDROID)
1488       // TODO(sgurun) android_webview hack
1489       // PrintForPrintPreview
1490       blink::WebFrame* print_frame = NULL;
1491       // This may not be the right frame, but the alert will be modal,
1492       // therefore it works well enough.
1493       GetPrintFrame(&print_frame);
1494       if (print_frame) {
1495         render_view()->RunModalAlertDialog(
1496             print_frame,
1497             l10n_util::GetStringUTF16(
1498                 IDS_PRINT_INVALID_PRINTER_SETTINGS));
1499       }
1500 #endif  // !defined(OS_ANDROID)
1501     }
1502     return false;
1503   }
1504
1505   if (settings.params.dpi < kMinDpi || !settings.params.document_cookie) {
1506     print_preview_context_.set_error(PREVIEW_ERROR_UPDATING_PRINT_SETTINGS);
1507     return false;
1508   }
1509
1510   if (!job_settings->GetInteger(kPreviewUIID, &settings.params.preview_ui_id)) {
1511     NOTREACHED();
1512     print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1513     return false;
1514   }
1515
1516   if (!print_for_preview_) {
1517     // Validate expected print preview settings.
1518     if (!job_settings->GetInteger(kPreviewRequestID,
1519                                   &settings.params.preview_request_id) ||
1520         !job_settings->GetBoolean(kIsFirstRequest,
1521                                   &settings.params.is_first_request)) {
1522       NOTREACHED();
1523       print_preview_context_.set_error(PREVIEW_ERROR_BAD_SETTING);
1524       return false;
1525     }
1526
1527     settings.params.print_to_pdf = IsPrintToPdfRequested(*job_settings);
1528     UpdateFrameMarginsCssInfo(*job_settings);
1529     settings.params.print_scaling_option = GetPrintScalingOption(
1530         source_is_html, *job_settings, settings.params);
1531
1532     // Header/Footer: Set |header_footer_info_|.
1533     if (settings.params.display_header_footer) {
1534       header_footer_info_.reset(new base::DictionaryValue());
1535       header_footer_info_->SetDouble(kSettingHeaderFooterDate,
1536                                      base::Time::Now().ToJsTime());
1537       header_footer_info_->SetString(kSettingHeaderFooterURL,
1538                                      settings.params.url);
1539       header_footer_info_->SetString(kSettingHeaderFooterTitle,
1540                                      settings.params.title);
1541     }
1542   }
1543
1544   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
1545   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
1546                                              settings.params.document_cookie));
1547
1548   return true;
1549 }
1550
1551 bool PrintWebViewHelper::GetPrintSettingsFromUser(blink::WebFrame* frame,
1552                                                   const blink::WebNode& node,
1553                                                   int expected_pages_count) {
1554   PrintHostMsg_ScriptedPrint_Params params;
1555   PrintMsg_PrintPages_Params print_settings;
1556
1557   params.cookie = print_pages_params_->params.document_cookie;
1558   params.has_selection = frame->hasSelection();
1559   params.expected_pages_count = expected_pages_count;
1560   MarginType margin_type = DEFAULT_MARGINS;
1561   if (PrintingNodeOrPdfFrame(frame, node))
1562     margin_type = GetMarginsForPdf(frame, node);
1563   params.margin_type = margin_type;
1564
1565   Send(new PrintHostMsg_DidShowPrintDialog(routing_id()));
1566
1567   // PrintHostMsg_ScriptedPrint will reset print_scaling_option, so we save the
1568   // value before and restore it afterwards.
1569   blink::WebPrintScalingOption scaling_option =
1570       print_pages_params_->params.print_scaling_option;
1571
1572   print_pages_params_.reset();
1573   IPC::SyncMessage* msg =
1574       new PrintHostMsg_ScriptedPrint(routing_id(), params, &print_settings);
1575   msg->EnableMessagePumping();
1576   Send(msg);
1577   print_pages_params_.reset(new PrintMsg_PrintPages_Params(print_settings));
1578
1579   print_pages_params_->params.print_scaling_option = scaling_option;
1580   return (print_settings.params.dpi && print_settings.params.document_cookie);
1581 }
1582
1583 bool PrintWebViewHelper::RenderPagesForPrint(blink::WebLocalFrame* frame,
1584                                              const blink::WebNode& node) {
1585   if (!frame || prep_frame_view_)
1586     return false;
1587   const PrintMsg_PrintPages_Params& params = *print_pages_params_;
1588   const PrintMsg_Print_Params& print_params = params.params;
1589   prep_frame_view_.reset(new PrepareFrameAndViewForPrint(
1590       print_params, frame, node, ignore_css_margins_));
1591   DCHECK(!print_pages_params_->params.selection_only ||
1592          print_pages_params_->pages.empty());
1593   prep_frame_view_->CopySelectionIfNeeded(
1594       render_view()->GetWebkitPreferences(),
1595       base::Bind(&PrintWebViewHelper::OnFramePreparedForPrintPages,
1596                  base::Unretained(this)));
1597   return true;
1598 }
1599
1600 #if defined(OS_POSIX)
1601 bool PrintWebViewHelper::CopyMetafileDataToSharedMem(
1602     PdfMetafileSkia* metafile,
1603     base::SharedMemoryHandle* shared_mem_handle) {
1604   uint32 buf_size = metafile->GetDataSize();
1605   scoped_ptr<base::SharedMemory> shared_buf(
1606       content::RenderThread::Get()->HostAllocateSharedMemoryBuffer(
1607           buf_size).release());
1608
1609   if (shared_buf.get()) {
1610     if (shared_buf->Map(buf_size)) {
1611       metafile->GetData(shared_buf->memory(), buf_size);
1612       shared_buf->GiveToProcess(base::GetCurrentProcessHandle(),
1613                                 shared_mem_handle);
1614       return true;
1615     }
1616   }
1617   NOTREACHED();
1618   return false;
1619 }
1620 #endif  // defined(OS_POSIX)
1621
1622 bool PrintWebViewHelper::IsScriptInitiatedPrintTooFrequent(
1623     blink::WebFrame* frame) {
1624   const int kMinSecondsToIgnoreJavascriptInitiatedPrint = 2;
1625   const int kMaxSecondsToIgnoreJavascriptInitiatedPrint = 32;
1626   bool too_frequent = false;
1627
1628   // Check if there is script repeatedly trying to print and ignore it if too
1629   // frequent.  The first 3 times, we use a constant wait time, but if this
1630   // gets excessive, we switch to exponential wait time. So for a page that
1631   // calls print() in a loop the user will need to cancel the print dialog
1632   // after: [2, 2, 2, 4, 8, 16, 32, 32, ...] seconds.
1633   // This gives the user time to navigate from the page.
1634   if (user_cancelled_scripted_print_count_ > 0) {
1635     base::TimeDelta diff = base::Time::Now() - last_cancelled_script_print_;
1636     int min_wait_seconds = kMinSecondsToIgnoreJavascriptInitiatedPrint;
1637     if (user_cancelled_scripted_print_count_ > 3) {
1638       min_wait_seconds = std::min(
1639           kMinSecondsToIgnoreJavascriptInitiatedPrint <<
1640               (user_cancelled_scripted_print_count_ - 3),
1641           kMaxSecondsToIgnoreJavascriptInitiatedPrint);
1642     }
1643     if (diff.InSeconds() < min_wait_seconds) {
1644       too_frequent = true;
1645     }
1646   }
1647
1648   if (!too_frequent)
1649     return false;
1650
1651   blink::WebString message(
1652       blink::WebString::fromUTF8("Ignoring too frequent calls to print()."));
1653   frame->addMessageToConsole(
1654       blink::WebConsoleMessage(
1655           blink::WebConsoleMessage::LevelWarning, message));
1656   return true;
1657 }
1658
1659 void PrintWebViewHelper::ResetScriptedPrintCount() {
1660   // Reset cancel counter on successful print.
1661   user_cancelled_scripted_print_count_ = 0;
1662 }
1663
1664 void PrintWebViewHelper::IncrementScriptedPrintCount() {
1665   ++user_cancelled_scripted_print_count_;
1666   last_cancelled_script_print_ = base::Time::Now();
1667 }
1668
1669 void PrintWebViewHelper::ShowScriptedPrintPreview() {
1670   if (is_scripted_preview_delayed_) {
1671     is_scripted_preview_delayed_ = false;
1672     Send(new PrintHostMsg_ShowScriptedPrintPreview(routing_id(),
1673             print_preview_context_.IsModifiable()));
1674   }
1675 }
1676
1677 void PrintWebViewHelper::RequestPrintPreview(PrintPreviewRequestType type) {
1678   const bool is_modifiable = print_preview_context_.IsModifiable();
1679   const bool has_selection = print_preview_context_.HasSelection();
1680   PrintHostMsg_RequestPrintPreview_Params params;
1681   params.is_modifiable = is_modifiable;
1682   params.has_selection = has_selection;
1683   switch (type) {
1684     case PRINT_PREVIEW_SCRIPTED: {
1685       // Shows scripted print preview in two stages.
1686       // 1. PrintHostMsg_SetupScriptedPrintPreview blocks this call and JS by
1687       //    pumping messages here.
1688       // 2. PrintHostMsg_ShowScriptedPrintPreview shows preview once the
1689       //    document has been loaded.
1690       is_scripted_preview_delayed_ = true;
1691       if (is_loading_ && GetPlugin(print_preview_context_.source_frame())) {
1692         // Wait for DidStopLoading. Plugins may not know the correct
1693         // |is_modifiable| value until they are fully loaded, which occurs when
1694         // DidStopLoading() is called. Defer showing the preview until then.
1695       } else {
1696         base::MessageLoop::current()->PostTask(
1697             FROM_HERE,
1698             base::Bind(&PrintWebViewHelper::ShowScriptedPrintPreview,
1699                        weak_ptr_factory_.GetWeakPtr()));
1700       }
1701       IPC::SyncMessage* msg =
1702           new PrintHostMsg_SetupScriptedPrintPreview(routing_id());
1703       msg->EnableMessagePumping();
1704       Send(msg);
1705       is_scripted_preview_delayed_ = false;
1706       return;
1707     }
1708     case PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME: {
1709       break;
1710     }
1711     case PRINT_PREVIEW_USER_INITIATED_SELECTION: {
1712       DCHECK(has_selection);
1713       params.selection_only = has_selection;
1714       break;
1715     }
1716     case PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE: {
1717       params.webnode_only = true;
1718       break;
1719     }
1720     default: {
1721       NOTREACHED();
1722       return;
1723     }
1724   }
1725   Send(new PrintHostMsg_RequestPrintPreview(routing_id(), params));
1726 }
1727
1728 bool PrintWebViewHelper::CheckForCancel() {
1729   const PrintMsg_Print_Params& print_params = print_pages_params_->params;
1730   bool cancel = false;
1731   Send(new PrintHostMsg_CheckForCancel(routing_id(),
1732                                        print_params.preview_ui_id,
1733                                        print_params.preview_request_id,
1734                                        &cancel));
1735   if (cancel)
1736     notify_browser_of_print_failure_ = false;
1737   return cancel;
1738 }
1739
1740 bool PrintWebViewHelper::PreviewPageRendered(int page_number,
1741                                              PdfMetafileSkia* metafile) {
1742   DCHECK_GE(page_number, FIRST_PAGE_INDEX);
1743
1744   // For non-modifiable files, |metafile| should be NULL, so do not bother
1745   // sending a message. If we don't generate draft metafiles, |metafile| is
1746   // NULL.
1747   if (!print_preview_context_.IsModifiable() ||
1748       !print_preview_context_.generate_draft_pages()) {
1749     DCHECK(!metafile);
1750     return true;
1751   }
1752
1753   if (!metafile) {
1754     NOTREACHED();
1755     print_preview_context_.set_error(
1756         PREVIEW_ERROR_PAGE_RENDERED_WITHOUT_METAFILE);
1757     return false;
1758   }
1759
1760   PrintHostMsg_DidPreviewPage_Params preview_page_params;
1761   // Get the size of the resulting metafile.
1762   uint32 buf_size = metafile->GetDataSize();
1763   DCHECK_GT(buf_size, 0u);
1764   if (!CopyMetafileDataToSharedMem(
1765       metafile, &(preview_page_params.metafile_data_handle))) {
1766     LOG(ERROR) << "CopyMetafileDataToSharedMem failed";
1767     print_preview_context_.set_error(PREVIEW_ERROR_METAFILE_COPY_FAILED);
1768     return false;
1769   }
1770   preview_page_params.data_size = buf_size;
1771   preview_page_params.page_number = page_number;
1772   preview_page_params.preview_request_id =
1773       print_pages_params_->params.preview_request_id;
1774
1775   Send(new PrintHostMsg_DidPreviewPage(routing_id(), preview_page_params));
1776   return true;
1777 }
1778
1779 PrintWebViewHelper::PrintPreviewContext::PrintPreviewContext()
1780     : total_page_count_(0),
1781       current_page_index_(0),
1782       generate_draft_pages_(true),
1783       print_ready_metafile_page_count_(0),
1784       error_(PREVIEW_ERROR_NONE),
1785       state_(UNINITIALIZED) {
1786 }
1787
1788 PrintWebViewHelper::PrintPreviewContext::~PrintPreviewContext() {
1789 }
1790
1791 void PrintWebViewHelper::PrintPreviewContext::InitWithFrame(
1792     blink::WebLocalFrame* web_frame) {
1793   DCHECK(web_frame);
1794   DCHECK(!IsRendering());
1795   state_ = INITIALIZED;
1796   source_frame_.Reset(web_frame);
1797   source_node_.reset();
1798 }
1799
1800 void PrintWebViewHelper::PrintPreviewContext::InitWithNode(
1801     const blink::WebNode& web_node) {
1802   DCHECK(!web_node.isNull());
1803   DCHECK(web_node.document().frame());
1804   DCHECK(!IsRendering());
1805   state_ = INITIALIZED;
1806   source_frame_.Reset(web_node.document().frame());
1807   source_node_ = web_node;
1808 }
1809
1810 void PrintWebViewHelper::PrintPreviewContext::OnPrintPreview() {
1811   DCHECK_EQ(INITIALIZED, state_);
1812   ClearContext();
1813 }
1814
1815 bool PrintWebViewHelper::PrintPreviewContext::CreatePreviewDocument(
1816     PrepareFrameAndViewForPrint* prepared_frame,
1817     const std::vector<int>& pages) {
1818   DCHECK_EQ(INITIALIZED, state_);
1819   state_ = RENDERING;
1820
1821   // Need to make sure old object gets destroyed first.
1822   prep_frame_view_.reset(prepared_frame);
1823   prep_frame_view_->StartPrinting();
1824
1825   total_page_count_ = prep_frame_view_->GetExpectedPageCount();
1826   if (total_page_count_ == 0) {
1827     LOG(ERROR) << "CreatePreviewDocument got 0 page count";
1828     set_error(PREVIEW_ERROR_ZERO_PAGES);
1829     return false;
1830   }
1831
1832   metafile_.reset(new PdfMetafileSkia);
1833   if (!metafile_->Init()) {
1834     set_error(PREVIEW_ERROR_METAFILE_INIT_FAILED);
1835     LOG(ERROR) << "PdfMetafileSkia Init failed";
1836     return false;
1837   }
1838
1839   current_page_index_ = 0;
1840   pages_to_render_ = pages;
1841   // Sort and make unique.
1842   std::sort(pages_to_render_.begin(), pages_to_render_.end());
1843   pages_to_render_.resize(std::unique(pages_to_render_.begin(),
1844                                       pages_to_render_.end()) -
1845                           pages_to_render_.begin());
1846   // Remove invalid pages.
1847   pages_to_render_.resize(std::lower_bound(pages_to_render_.begin(),
1848                                            pages_to_render_.end(),
1849                                            total_page_count_) -
1850                           pages_to_render_.begin());
1851   print_ready_metafile_page_count_ = pages_to_render_.size();
1852   if (pages_to_render_.empty()) {
1853     print_ready_metafile_page_count_ = total_page_count_;
1854     // Render all pages.
1855     for (int i = 0; i < total_page_count_; ++i)
1856       pages_to_render_.push_back(i);
1857   } else if (generate_draft_pages_) {
1858     int pages_index = 0;
1859     for (int i = 0; i < total_page_count_; ++i) {
1860       if (pages_index < print_ready_metafile_page_count_ &&
1861           i == pages_to_render_[pages_index]) {
1862         pages_index++;
1863         continue;
1864       }
1865       pages_to_render_.push_back(i);
1866     }
1867   }
1868
1869   document_render_time_ = base::TimeDelta();
1870   begin_time_ = base::TimeTicks::Now();
1871
1872   return true;
1873 }
1874
1875 void PrintWebViewHelper::PrintPreviewContext::RenderedPreviewPage(
1876     const base::TimeDelta& page_time) {
1877   DCHECK_EQ(RENDERING, state_);
1878   document_render_time_ += page_time;
1879   UMA_HISTOGRAM_TIMES("PrintPreview.RenderPDFPageTime", page_time);
1880 }
1881
1882 void PrintWebViewHelper::PrintPreviewContext::AllPagesRendered() {
1883   DCHECK_EQ(RENDERING, state_);
1884   state_ = DONE;
1885   prep_frame_view_->FinishPrinting();
1886 }
1887
1888 void PrintWebViewHelper::PrintPreviewContext::FinalizePrintReadyDocument() {
1889   DCHECK(IsRendering());
1890
1891   base::TimeTicks begin_time = base::TimeTicks::Now();
1892   metafile_->FinishDocument();
1893
1894   if (print_ready_metafile_page_count_ <= 0) {
1895     NOTREACHED();
1896     return;
1897   }
1898
1899   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderToPDFTime",
1900                              document_render_time_);
1901   base::TimeDelta total_time = (base::TimeTicks::Now() - begin_time) +
1902                                document_render_time_;
1903   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderAndGeneratePDFTime",
1904                              total_time);
1905   UMA_HISTOGRAM_MEDIUM_TIMES("PrintPreview.RenderAndGeneratePDFTimeAvgPerPage",
1906                              total_time / pages_to_render_.size());
1907 }
1908
1909 void PrintWebViewHelper::PrintPreviewContext::Finished() {
1910   DCHECK_EQ(DONE, state_);
1911   state_ = INITIALIZED;
1912   ClearContext();
1913 }
1914
1915 void PrintWebViewHelper::PrintPreviewContext::Failed(bool report_error) {
1916   DCHECK(state_ == INITIALIZED || state_ == RENDERING);
1917   state_ = INITIALIZED;
1918   if (report_error) {
1919     DCHECK_NE(PREVIEW_ERROR_NONE, error_);
1920     UMA_HISTOGRAM_ENUMERATION("PrintPreview.RendererError", error_,
1921                               PREVIEW_ERROR_LAST_ENUM);
1922   }
1923   ClearContext();
1924 }
1925
1926 int PrintWebViewHelper::PrintPreviewContext::GetNextPageNumber() {
1927   DCHECK_EQ(RENDERING, state_);
1928   if (IsFinalPageRendered())
1929     return -1;
1930   return pages_to_render_[current_page_index_++];
1931 }
1932
1933 bool PrintWebViewHelper::PrintPreviewContext::IsRendering() const {
1934   return state_ == RENDERING || state_ == DONE;
1935 }
1936
1937 bool PrintWebViewHelper::PrintPreviewContext::IsModifiable() {
1938   // The only kind of node we can print right now is a PDF node.
1939   return !PrintingNodeOrPdfFrame(source_frame(), source_node_);
1940 }
1941
1942 bool PrintWebViewHelper::PrintPreviewContext::HasSelection() {
1943   return IsModifiable() && source_frame()->hasSelection();
1944 }
1945
1946 bool PrintWebViewHelper::PrintPreviewContext::IsLastPageOfPrintReadyMetafile()
1947     const {
1948   DCHECK(IsRendering());
1949   return current_page_index_ == print_ready_metafile_page_count_;
1950 }
1951
1952 bool  PrintWebViewHelper::PrintPreviewContext::IsFinalPageRendered() const {
1953   DCHECK(IsRendering());
1954   return static_cast<size_t>(current_page_index_) == pages_to_render_.size();
1955 }
1956
1957 void PrintWebViewHelper::PrintPreviewContext::set_generate_draft_pages(
1958     bool generate_draft_pages) {
1959   DCHECK_EQ(INITIALIZED, state_);
1960   generate_draft_pages_ = generate_draft_pages;
1961 }
1962
1963 void PrintWebViewHelper::PrintPreviewContext::set_error(
1964     enum PrintPreviewErrorBuckets error) {
1965   error_ = error;
1966 }
1967
1968 blink::WebLocalFrame* PrintWebViewHelper::PrintPreviewContext::source_frame() {
1969   DCHECK_NE(UNINITIALIZED, state_);
1970   return source_frame_.GetFrame();
1971 }
1972
1973 const blink::WebNode&
1974     PrintWebViewHelper::PrintPreviewContext::source_node() const {
1975   DCHECK_NE(UNINITIALIZED, state_);
1976   return source_node_;
1977 }
1978
1979 blink::WebLocalFrame*
1980 PrintWebViewHelper::PrintPreviewContext::prepared_frame() {
1981   DCHECK_NE(UNINITIALIZED, state_);
1982   return prep_frame_view_->frame();
1983 }
1984
1985 const blink::WebNode&
1986     PrintWebViewHelper::PrintPreviewContext::prepared_node() const {
1987   DCHECK_NE(UNINITIALIZED, state_);
1988   return prep_frame_view_->node();
1989 }
1990
1991 int PrintWebViewHelper::PrintPreviewContext::total_page_count() const {
1992   DCHECK_NE(UNINITIALIZED, state_);
1993   return total_page_count_;
1994 }
1995
1996 bool PrintWebViewHelper::PrintPreviewContext::generate_draft_pages() const {
1997   return generate_draft_pages_;
1998 }
1999
2000 PdfMetafileSkia* PrintWebViewHelper::PrintPreviewContext::metafile() {
2001   DCHECK(IsRendering());
2002   return metafile_.get();
2003 }
2004
2005 int PrintWebViewHelper::PrintPreviewContext::last_error() const {
2006   return error_;
2007 }
2008
2009 gfx::Size PrintWebViewHelper::PrintPreviewContext::GetPrintCanvasSize() const {
2010   DCHECK(IsRendering());
2011   return prep_frame_view_->GetPrintCanvasSize();
2012 }
2013
2014 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
2015   prep_frame_view_.reset();
2016   metafile_.reset();
2017   pages_to_render_.clear();
2018   error_ = PREVIEW_ERROR_NONE;
2019 }
2020
2021 }  // namespace printing