components/printing/renderer/print_web_view_helper.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef COMPONENTS_PRINTING_RENDERER_PRINT_WEB_VIEW_HELPER_H_
   6 #define COMPONENTS_PRINTING_RENDERER_PRINT_WEB_VIEW_HELPER_H_
   7
   8 #include <vector>
   9
  10 #include "base/callback.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/memory/shared_memory.h"
  14 #include "base/memory/weak_ptr.h"
  15 #include "base/time/time.h"
  16 #include "content/public/renderer/render_view_observer.h"
  17 #include "content/public/renderer/render_view_observer_tracker.h"
  18 #include "printing/pdf_metafile_skia.h"
  19 #include "third_party/WebKit/public/platform/WebCanvas.h"
  20 #include "third_party/WebKit/public/web/WebNode.h"
  21 #include "third_party/WebKit/public/web/WebPrintParams.h"
  22 #include "ui/gfx/geometry/size.h"
  23
  24 struct PrintMsg_Print_Params;
  25 struct PrintMsg_PrintPage_Params;
  26 struct PrintMsg_PrintPages_Params;
  27 struct PrintHostMsg_SetOptionsFromDocument_Params;
  28
  29 namespace base {
  30 class DictionaryValue;
  31 }
  32
  33 namespace blink {
  34 class WebFrame;
  35 class WebView;
  36 }
  37
  38 namespace printing {
  39
  40 struct PageSizeMargins;
  41 class PrepareFrameAndViewForPrint;
  42
  43 // Stores reference to frame using WebVew and unique name.
  44 // Workaround to modal dialog issue on Linux. crbug.com/236147.
  45 // If WebFrame someday supports WeakPtr, we should use it here.
  46 class FrameReference {
  47  public:
  48   explicit FrameReference(blink::WebLocalFrame* frame);
  49   FrameReference();
  50   ~FrameReference();
  51
  52   void Reset(blink::WebLocalFrame* frame);
  53
  54   blink::WebLocalFrame* GetFrame();
  55   blink::WebView* view();
  56
  57  private:
  58   blink::WebView* view_;
  59   blink::WebLocalFrame* frame_;
  60 };
  61
  62 // PrintWebViewHelper handles most of the printing grunt work for RenderView.
  63 // We plan on making print asynchronous and that will require copying the DOM
  64 // of the document and creating a new WebView with the contents.
  65 class PrintWebViewHelper
  66     : public content::RenderViewObserver,
  67       public content::RenderViewObserverTracker<PrintWebViewHelper> {
  68  public:
  69   class Delegate {
  70    public:
  71     virtual ~Delegate() {}
  72
  73     // Cancels prerender if it's currently in progress and returns |true| if
  74     // the cancellation was done with success.
  75     virtual bool CancelPrerender(content::RenderView* render_view,
  76                                  int routing_id) = 0;
  77
  78     // Returns the element to be printed. Returns a null WebElement if
  79     // a pdf plugin element can't be extracted from the frame.
  80     virtual blink::WebElement GetPdfElement(blink::WebLocalFrame* frame) = 0;
  81
  82     // Used to know whether the content to print could be nested in an iframe.
  83     virtual bool IsOutOfProcessPdfEnabled() = 0;
  84
  85     virtual bool IsPrintPreviewEnabled() = 0;
  86
  87     // If true, the user can be asked to provide print settings.
  88     // The default implementation returns |true|.
  89     virtual bool IsAskPrintSettingsEnabled();
  90
  91     // If false, window.print() won't do anything.
  92     // The default implementation returns |true|.
  93     virtual bool IsScriptedPrintEnabled();
  94
  95     // Returns true if printing is overridden and the default behavior should be
  96     // skipped for |frame|.
  97     virtual bool OverridePrint(blink::WebLocalFrame* frame) = 0;
  98   };
  99
 100   PrintWebViewHelper(content::RenderView* render_view,
 101                      scoped_ptr<Delegate> delegate);
 102   ~PrintWebViewHelper() override;
 103
 104   // Disable print preview and switch to system dialog printing even if full
 105   // printing is build-in. This method is used by CEF.
 106   static void DisablePreview();
 107
 108   bool IsPrintingEnabled();
 109
 110   void PrintNode(const blink::WebNode& node);
 111
 112  private:
 113   friend class PrintWebViewHelperTestBase;
 114   FRIEND_TEST_ALL_PREFIXES(PrintWebViewHelperPreviewTest,
 115                            BlockScriptInitiatedPrinting);
 116   FRIEND_TEST_ALL_PREFIXES(PrintWebViewHelperTest, OnPrintPages);
 117   FRIEND_TEST_ALL_PREFIXES(PrintWebViewHelperTest,
 118                            BlockScriptInitiatedPrinting);
 119   FRIEND_TEST_ALL_PREFIXES(PrintWebViewHelperTest,
 120                            BlockScriptInitiatedPrintingFromPopup);
 121 #if defined(OS_WIN) || defined(OS_MACOSX)
 122   FRIEND_TEST_ALL_PREFIXES(PrintWebViewHelperTest, PrintLayoutTest);
 123   FRIEND_TEST_ALL_PREFIXES(PrintWebViewHelperTest, PrintWithIframe);
 124 #endif  // defined(OS_WIN) || defined(OS_MACOSX)
 125
 126   enum PrintingResult {
 127     OK,
 128     FAIL_PRINT_INIT,
 129     FAIL_PRINT,
 130     FAIL_PREVIEW,
 131   };
 132
 133   enum PrintPreviewErrorBuckets {
 134     PREVIEW_ERROR_NONE,  // Always first.
 135     PREVIEW_ERROR_BAD_SETTING,
 136     PREVIEW_ERROR_METAFILE_COPY_FAILED,
 137     PREVIEW_ERROR_METAFILE_INIT_FAILED,
 138     PREVIEW_ERROR_ZERO_PAGES,
 139     PREVIEW_ERROR_MAC_DRAFT_METAFILE_INIT_FAILED,
 140     PREVIEW_ERROR_PAGE_RENDERED_WITHOUT_METAFILE,
 141     PREVIEW_ERROR_INVALID_PRINTER_SETTINGS,
 142     PREVIEW_ERROR_LAST_ENUM  // Always last.
 143   };
 144
 145   enum PrintPreviewRequestType {
 146     PRINT_PREVIEW_USER_INITIATED_ENTIRE_FRAME,
 147     PRINT_PREVIEW_USER_INITIATED_SELECTION,
 148     PRINT_PREVIEW_USER_INITIATED_CONTEXT_NODE,
 149     PRINT_PREVIEW_SCRIPTED  // triggered by window.print().
 150   };
 151
 152   // RenderViewObserver implementation.
 153   bool OnMessageReceived(const IPC::Message& message) override;
 154   void PrintPage(blink::WebLocalFrame* frame, bool user_initiated) override;
 155   void DidStartLoading() override;
 156   void DidStopLoading() override;
 157
 158   // Message handlers ---------------------------------------------------------
 159 #if defined(ENABLE_BASIC_PRINTING)
 160   void OnPrintPages();
 161   void OnPrintForSystemDialog();
 162 #endif  // ENABLE_BASIC_PRINTING
 163   void OnInitiatePrintPreview(bool selection_only);
 164   void OnPrintPreview(const base::DictionaryValue& settings);
 165   void OnPrintForPrintPreview(const base::DictionaryValue& job_settings);
 166   void OnPrintingDone(bool success);
 167
 168   // Get |page_size| and |content_area| information from
 169   // |page_layout_in_points|.
 170   void GetPageSizeAndContentAreaFromPageLayout(
 171       const PageSizeMargins& page_layout_in_points,
 172       gfx::Size* page_size,
 173       gfx::Rect* content_area);
 174
 175   // Update |ignore_css_margins_| based on settings.
 176   void UpdateFrameMarginsCssInfo(const base::DictionaryValue& settings);
 177
 178   // Returns true if the current destination printer is PRINT_TO_PDF.
 179   bool IsPrintToPdfRequested(const base::DictionaryValue& settings);
 180
 181   // Prepare frame for creating preview document.
 182   void PrepareFrameForPreviewDocument();
 183
 184   // Continue creating preview document.
 185   void OnFramePreparedForPreviewDocument();
 186
 187   // Initialize the print preview document.
 188   bool CreatePreviewDocument();
 189
 190   // Renders a print preview page. |page_number| is 0-based.
 191   // Returns true if print preview should continue, false on failure.
 192   bool RenderPreviewPage(int page_number,
 193                          const PrintMsg_Print_Params& print_params);
 194
 195   // Finalize the print ready preview document.
 196   bool FinalizePrintReadyDocument();
 197
 198   // Enable/Disable window.print calls.  If |blocked| is true window.print
 199   // calls will silently fail.  Call with |blocked| set to false to reenable.
 200   void SetScriptedPrintBlocked(bool blocked);
 201
 202   // Main printing code -------------------------------------------------------
 203
 204   // |is_scripted| should be true when the call is coming from window.print()
 205   void Print(blink::WebLocalFrame* frame,
 206              const blink::WebNode& node,
 207              bool is_scripted);
 208
 209   // Notification when printing is done - signal tear-down/free resources.
 210   void DidFinishPrinting(PrintingResult result);
 211
 212   // Print Settings -----------------------------------------------------------
 213
 214   // Initialize print page settings with default settings.
 215   // Used only for native printing workflow.
 216   bool InitPrintSettings(bool fit_to_paper_size);
 217
 218   // Calculate number of pages in source document.
 219   bool CalculateNumberOfPages(blink::WebLocalFrame* frame,
 220                               const blink::WebNode& node,
 221                               int* number_of_pages);
 222
 223   // Set options for print preset from source PDF document.
 224   bool SetOptionsFromPdfDocument(
 225       PrintHostMsg_SetOptionsFromDocument_Params* options);
 226
 227   // Update the current print settings with new |passed_job_settings|.
 228   // |passed_job_settings| dictionary contains print job details such as printer
 229   // name, number of copies, page range, etc.
 230   bool UpdatePrintSettings(blink::WebLocalFrame* frame,
 231                            const blink::WebNode& node,
 232                            const base::DictionaryValue& passed_job_settings);
 233
 234   // Get final print settings from the user.
 235   // Return false if the user cancels or on error.
 236   bool GetPrintSettingsFromUser(blink::WebLocalFrame* frame,
 237                                 const blink::WebNode& node,
 238                                 int expected_pages_count,
 239                                 bool is_scripted);
 240
 241   // Page Printing / Rendering ------------------------------------------------
 242
 243   void OnFramePreparedForPrintPages();
 244   void PrintPages();
 245   bool PrintPagesNative(blink::WebFrame* frame, int page_count);
 246   void FinishFramePrinting();
 247
 248   // Prints the page listed in |params|.
 249 #if defined(OS_LINUX) || defined(OS_ANDROID)
 250   void PrintPageInternal(const PrintMsg_PrintPage_Params& params,
 251                          blink::WebFrame* frame,
 252                          PdfMetafileSkia* metafile);
 253 #elif defined(OS_WIN)
 254   void PrintPageInternal(const PrintMsg_PrintPage_Params& params,
 255                          blink::WebFrame* frame,
 256                          PdfMetafileSkia* metafile,
 257                          gfx::Size* page_size_in_dpi,
 258                          gfx::Rect* content_area_in_dpi);
 259 #else
 260   void PrintPageInternal(const PrintMsg_PrintPage_Params& params,
 261                          blink::WebFrame* frame);
 262 #endif
 263
 264   // Render the frame for printing.
 265   bool RenderPagesForPrint(blink::WebLocalFrame* frame,
 266                            const blink::WebNode& node);
 267
 268   // Platform specific helper function for rendering page(s) to |metafile|.
 269 #if defined(OS_MACOSX)
 270   void RenderPage(const PrintMsg_Print_Params& params,
 271                   int page_number,
 272                   blink::WebFrame* frame,
 273                   bool is_preview,
 274                   PdfMetafileSkia* metafile,
 275                   gfx::Size* page_size,
 276                   gfx::Rect* content_rect);
 277 #endif  // defined(OS_MACOSX)
 278
 279   // Renders page contents from |frame| to |content_area| of |canvas|.
 280   // |page_number| is zero-based.
 281   // When method is called, canvas should be setup to draw to |canvas_area|
 282   // with |scale_factor|.
 283   static float RenderPageContent(blink::WebFrame* frame,
 284                                  int page_number,
 285                                  const gfx::Rect& canvas_area,
 286                                  const gfx::Rect& content_area,
 287                                  double scale_factor,
 288                                  blink::WebCanvas* canvas);
 289
 290   // Helper methods -----------------------------------------------------------
 291
 292   bool CopyMetafileDataToSharedMem(PdfMetafileSkia* metafile,
 293                                    base::SharedMemoryHandle* shared_mem_handle);
 294
 295   // Helper method to get page layout in points and fit to page if needed.
 296   static void ComputePageLayoutInPointsForCss(
 297       blink::WebFrame* frame,
 298       int page_index,
 299       const PrintMsg_Print_Params& default_params,
 300       bool ignore_css_margins,
 301       double* scale_factor,
 302       PageSizeMargins* page_layout_in_points);
 303
 304 #if defined(ENABLE_PRINT_PREVIEW)
 305   // Given the |device| and |canvas| to draw on, prints the appropriate headers
 306   // and footers using strings from |header_footer_info| on to the canvas.
 307   static void PrintHeaderAndFooter(blink::WebCanvas* canvas,
 308                                    int page_number,
 309                                    int total_pages,
 310                                    const blink::WebFrame& source_frame,
 311                                    float webkit_scale_factor,
 312                                    const PageSizeMargins& page_layout_in_points,
 313                                    const PrintMsg_Print_Params& params);
 314 #endif  // defined(ENABLE_PRINT_PREVIEW)
 315
 316   bool GetPrintFrame(blink::WebLocalFrame** frame);
 317
 318   // Script Initiated Printing ------------------------------------------------
 319
 320   // Return true if script initiated printing is currently
 321   // allowed. |user_initiated| should be true when a user event triggered the
 322   // script, most likely by pressing a print button on the page.
 323   bool IsScriptInitiatedPrintAllowed(blink::WebFrame* frame,
 324                                      bool user_initiated);
 325
 326   // Shows scripted print preview when options from plugin are available.
 327   void ShowScriptedPrintPreview();
 328
 329   void RequestPrintPreview(PrintPreviewRequestType type);
 330
 331   // Checks whether print preview should continue or not.
 332   // Returns true if canceling, false if continuing.
 333   bool CheckForCancel();
 334
 335   // Notifies the browser a print preview page has been rendered.
 336   // |page_number| is 0-based.
 337   // For a valid |page_number| with modifiable content,
 338   // |metafile| is the rendered page. Otherwise |metafile| is NULL.
 339   // Returns true if print preview should continue, false on failure.
 340   bool PreviewPageRendered(int page_number, PdfMetafileSkia* metafile);
 341
 342   void SetPrintPagesParams(const PrintMsg_PrintPages_Params& settings);
 343
 344   // WebView used only to print the selection.
 345   scoped_ptr<PrepareFrameAndViewForPrint> prep_frame_view_;
 346   bool reset_prep_frame_view_;
 347
 348   scoped_ptr<PrintMsg_PrintPages_Params> print_pages_params_;
 349   bool is_print_ready_metafile_sent_;
 350   bool ignore_css_margins_;
 351
 352   // Used for scripted initiated printing blocking.
 353   bool is_scripted_printing_blocked_;
 354
 355   // Let the browser process know of a printing failure. Only set to false when
 356   // the failure came from the browser in the first place.
 357   bool notify_browser_of_print_failure_;
 358
 359   // True, when printing from print preview.
 360   bool print_for_preview_;
 361
 362   // Used to check the prerendering status.
 363   const scoped_ptr<Delegate> delegate_;
 364
 365   // Keeps track of the state of print preview between messages.
 366   // TODO(vitalybuka): Create PrintPreviewContext when needed and delete after
 367   // use. Now it's interaction with various messages is confusing.
 368   class PrintPreviewContext {
 369    public:
 370     PrintPreviewContext();
 371     ~PrintPreviewContext();
 372
 373     // Initializes the print preview context. Need to be called to set
 374     // the |web_frame| / |web_node| to generate the print preview for.
 375     void InitWithFrame(blink::WebLocalFrame* web_frame);
 376     void InitWithNode(const blink::WebNode& web_node);
 377
 378     // Does bookkeeping at the beginning of print preview.
 379     void OnPrintPreview();
 380
 381     // Create the print preview document. |pages| is empty to print all pages.
 382     // Takes ownership of |prepared_frame|.
 383     bool CreatePreviewDocument(PrepareFrameAndViewForPrint* prepared_frame,
 384                                const std::vector<int>& pages);
 385
 386     // Called after a page gets rendered. |page_time| is how long the
 387     // rendering took.
 388     void RenderedPreviewPage(const base::TimeDelta& page_time);
 389
 390     // Updates the print preview context when the required pages are rendered.
 391     void AllPagesRendered();
 392
 393     // Finalizes the print ready preview document.
 394     void FinalizePrintReadyDocument();
 395
 396     // Cleanup after print preview finishes.
 397     void Finished();
 398
 399     // Cleanup after print preview fails.
 400     void Failed(bool report_error);
 401
 402     // Helper functions
 403     int GetNextPageNumber();
 404     bool IsRendering() const;
 405     bool IsModifiable();
 406     bool HasSelection();
 407     bool IsLastPageOfPrintReadyMetafile() const;
 408     bool IsFinalPageRendered() const;
 409
 410     // Setters
 411     void set_generate_draft_pages(bool generate_draft_pages);
 412     void set_error(enum PrintPreviewErrorBuckets error);
 413
 414     // Getters
 415     // Original frame for which preview was requested.
 416     blink::WebLocalFrame* source_frame();
 417     // Original node for which preview was requested.
 418     const blink::WebNode& source_node() const;
 419
 420     // Frame to be use to render preview. May be the same as source_frame(), or
 421     // generated from it, e.g. copy of selected block.
 422     blink::WebLocalFrame* prepared_frame();
 423     // Node to be use to render preview. May be the same as source_node(), or
 424     // generated from it, e.g. copy of selected block.
 425     const blink::WebNode& prepared_node() const;
 426
 427     int total_page_count() const;
 428     bool generate_draft_pages() const;
 429     PdfMetafileSkia* metafile();
 430     int last_error() const;
 431
 432    private:
 433     enum State {
 434       UNINITIALIZED,  // Not ready to render.
 435       INITIALIZED,    // Ready to render.
 436       RENDERING,      // Rendering.
 437       DONE            // Finished rendering.
 438     };
 439
 440     // Reset some of the internal rendering context.
 441     void ClearContext();
 442
 443     // Specifies what to render for print preview.
 444     FrameReference source_frame_;
 445     blink::WebNode source_node_;
 446
 447     scoped_ptr<PrepareFrameAndViewForPrint> prep_frame_view_;
 448     scoped_ptr<PdfMetafileSkia> metafile_;
 449
 450     // Total page count in the renderer.
 451     int total_page_count_;
 452
 453     // The current page to render.
 454     int current_page_index_;
 455
 456     // List of page indices that need to be rendered.
 457     std::vector<int> pages_to_render_;
 458
 459     // True, when draft pages needs to be generated.
 460     bool generate_draft_pages_;
 461
 462     // Specifies the total number of pages in the print ready metafile.
 463     int print_ready_metafile_page_count_;
 464
 465     base::TimeDelta document_render_time_;
 466     base::TimeTicks begin_time_;
 467
 468     enum PrintPreviewErrorBuckets error_;
 469
 470     State state_;
 471   };
 472
 473   class ScriptingThrottler {
 474    public:
 475     ScriptingThrottler();
 476
 477     // Returns false if script initiated printing occurs too often.
 478     bool IsAllowed(blink::WebFrame* frame);
 479
 480     // Reset the counter for script initiated printing.
 481     // Scripted printing will be allowed to continue.
 482     void Reset();
 483
 484    private:
 485     base::Time last_print_;
 486     int count_ = 0;
 487     DISALLOW_COPY_AND_ASSIGN(ScriptingThrottler);
 488   };
 489
 490   ScriptingThrottler scripting_throttler_;
 491
 492   bool print_node_in_progress_;
 493   PrintPreviewContext print_preview_context_;
 494   bool is_loading_;
 495   bool is_scripted_preview_delayed_;
 496
 497   // Used to fix a race condition where the source is a PDF and print preview
 498   // hangs because RequestPrintPreview is called before DidStopLoading() is
 499   // called. This is a store for the RequestPrintPreview() call and its
 500   // parameters so that it can be invoked after DidStopLoading.
 501   base::Closure on_stop_loading_closure_;
 502
 503   base::WeakPtrFactory<PrintWebViewHelper> weak_ptr_factory_;
 504
 505   DISALLOW_COPY_AND_ASSIGN(PrintWebViewHelper);
 506 };
 507
 508 }  // namespace printing
 509
 510 #endif  // COMPONENTS_PRINTING_RENDERER_PRINT_WEB_VIEW_HELPER_H_