Added Header and Footer support using Skia

chrome/renderer/print_web_view_helper.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/print_web_view_helper.h"
 
+#if defined(USE_SKIA)
+#include <algorithm>
+#include <cmath>
+#endif
 #include <string>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/process_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/print_messages.h"
 #include "chrome/common/render_messages.h"
@@ skipping 12 matching lines @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSize.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebURLRequest.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebURLResponse.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_POSIX)
 #include "content/common/view_messages.h"
 #endif
 
+#if defined(USE_SKIA)
+#include "base/i18n/time_formatting.h"
+#include "base/string_number_conversions.h"
+#include "base/time.h"
+#include "skia/ext/vector_canvas.h"
+#include "skia/ext/vector_platform_device_skia.h"
+#include "third_party/skia/include/core/SkTypeface.h"
+#include "ui/base/text/text_elider.h"
+#endif  // USE_SKIA
+
+using base::Time;
 using printing::ConvertPixelsToPoint;
 using printing::ConvertPixelsToPointDouble;
+using printing::ConvertPointsToPixelDouble;
 using printing::ConvertUnit;
 using printing::ConvertUnitDouble;
 using WebKit::WebConsoleMessage;
 using WebKit::WebDocument;
 using WebKit::WebElement;
 using WebKit::WebFrame;
 using WebKit::WebNode;
 using WebKit::WebSize;
 using WebKit::WebString;
 using WebKit::WebURLRequest;
@@ skipping 29 matching lines @@
          oldParams.params.min_shrink == newParams.params.min_shrink &&
          oldParams.params.dpi == newParams.params.dpi &&
          oldParams.params.printable_size == newParams.params.printable_size &&
          oldParams.params.selection_only == newParams.params.selection_only &&
          oldParams.params.page_size == newParams.params.page_size &&
          oldParams.params.margin_top == newParams.params.margin_top &&
          oldParams.params.margin_left == newParams.params.margin_left &&
          oldParams.params.supports_alpha_blend ==
              newParams.params.supports_alpha_blend &&
          oldParams.pages.size() == newParams.pages.size() &&
+         oldParams.params.display_header_footer ==
+             newParams.params.display_header_footer &&
          std::equal(oldParams.pages.begin(), oldParams.pages.end(),
              newParams.pages.begin());
 }
 
 void CalculatePrintCanvasSize(const PrintMsg_Print_Params& print_params,
                               gfx::Size* result) {
   int dpi = GetDPI(&print_params);
   result->set_width(ConvertUnit(print_params.printable_size.width(), dpi,
                                 print_params.desired_dpi));
 
   result->set_height(ConvertUnit(print_params.printable_size.height(), dpi,
                                  print_params.desired_dpi));
 }
 
+#if defined(USE_SKIA)
+// Splits the horizontal width equally into segments with an interstice
+// between each segment. Returns the width of this segment.
+SkScalar GetSegmentWidth(const PageSizeMargins& page_layout) {
+  SkScalar page_width = page_layout.margin_left +
+                        page_layout.content_width +

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

nit: indent should be 4.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+                        page_layout.margin_right;
+  // Interstice is left at both ends of the page as well as between
+  // each region, so 1 is added.
+  SkScalar total_interstice_width =
+      (printing::kSettingHeaderFooterHorizontalRegions + 1) *
+      printing::kSettingHeaderFooterInterstice;
+  return (page_width - total_interstice_width) /
+         printing::kSettingHeaderFooterHorizontalRegions;

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

nit: indent should be 4.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+}
+
+// Given a text, the positions, and the paint object, this method gets the
+// coordinates and prints the text at those coordinates on the canvas.
+void PrintHeaderFooterText(
+    string16 text,
+    SkPaint paint,
+    skia::VectorCanvas* canvas,
+    printing::HorizontalHeaderFooterPosition horizontal_position,
+    printing::VerticalHeaderFooterPosition vertical_position,
+    float webkit_scale_factor,
+    const PageSizeMargins& page_layout,
+    const SkScalar& max_text_width,

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

POD should be passed in directly... i.e. SkScalar max_text_width,

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+    const gfx::Font& font,
+    const SkScalar& space_for_descenders) {

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

and here

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

I guess I misunderstood before... this isn't the space for descenders when
printing to the top.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

[Aayush Kumar, 2011/08/04 18:25:04]

Renamed back to "height_to_baseline"

[vandebo (ex-Chrome), 2011/08/04 20:46:21]

nit: hmm, maybe offset_to_baseline would be better - for the top, it's not
really height (since it's downward).

[Aayush Kumar, 2011/08/04 23:00:30]

Done.

+  text = ui::ElideText(text, font, ConvertPointsToPixelDouble(max_text_width),
+                       false);
+
+  size_t text_byte_length = text.length() * sizeof(char16);
+  // Get the (x, y) coordinate from where printing of the current text should
+  // start depending on the horizontal alignment (LEFT, RIGHT, CENTER) and
+  // vertical alignment (TOP, BOTTOM).
+  SkScalar text_width_in_points = paint.measureText(text.c_str(),
+                                                    text_byte_length);
+  SkScalar x = 0;
+  switch (horizontal_position) {
+    case printing::LEFT: {

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

{}'s are not needed on the cases statements in this switch or the next.

[Aayush Kumar, 2011/08/04 18:25:04]

According to the google C++ style guide, braces seem to be allowed.
(http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Loops_...)

[vandebo (ex-Chrome), 2011/08/04 20:46:21]

Indeed, but the overriding rule is to follow existing style.  Chrome's existing
style is to only include the {}'s if needed - i.e. if there are variables
introduced inside the {}'s.

[Aayush Kumar, 2011/08/04 23:00:30]

Done.

+      x = printing::kSettingHeaderFooterInterstice - page_layout.margin_left;
+      break;
+    }
+    case printing::RIGHT: {
+      x = page_layout.content_width + page_layout.margin_right -
+          printing::kSettingHeaderFooterInterstice - text_width_in_points;
+      break;
+    }
+    case printing::CENTER: {
+      SkScalar available_width = GetSegmentWidth(page_layout);
+      x = available_width - page_layout.margin_left +
+          (available_width - text_width_in_points) / 2;
+      break;
+    }
+    default: {
+      NOTREACHED();
+    }
+  }
+
+  SkScalar y = 0;
+  switch (vertical_position) {
+    case printing::TOP: {
+      y = printing::kSettingHeaderFooterInterstice -
+          page_layout.margin_top - space_for_descenders;
+      break;
+    }
+    case printing::BOTTOM: {
+      y = page_layout.margin_bottom + page_layout.content_height -
+          printing::kSettingHeaderFooterInterstice - space_for_descenders;
+      break;
+    }
+    default: {
+      NOTREACHED();
+    }
+  }
+
+  x = x / webkit_scale_factor;
+  y = y / webkit_scale_factor;
+  paint.setTextSize(paint.getTextSize() / webkit_scale_factor);
+  canvas->drawText(text.c_str(), text_byte_length, x, y, paint);
+}
+#endif  // USE_SKIA
+
 }  // namespace
 
+#if defined(USE_SKIA)
+// static - Not anonymous so that platform implementations can use it.
+void PrintWebViewHelper::PrintHeaderAndFooter(
+    SkDevice* device,
+    skia::VectorCanvas* canvas,
+    int page_number,
+    int total_pages,
+    float webkit_scale_factor,
+    const PageSizeMargins& page_layout,
+    const DictionaryValue& header_footer_info) {
+  // Set the drawing area to draw in the margins.
+  static_cast<skia::VectorPlatformDeviceSkia*>(device)->setDrawingArea(
+      SkPDFDevice::kMargin_DrawingArea);
+
+  // Setting up styles for the headers and footers text.
+  SkPaint paint;
+  paint.setColor(SK_ColorBLACK);
+  paint.setTextEncoding(SkPaint::kUTF16_TextEncoding);
+  paint.setTextSize(printing::kSettingHeaderFooterFontSize);
+  gfx::Font font(UTF8ToUTF16(printing::kSettingHeaderFooterFontName),
+                 ceil(ConvertPointsToPixelDouble(
+                     printing::kSettingHeaderFooterFontSize)));
+  paint.setTypeface(SkTypeface::CreateFromName(
+      UTF16ToUTF8(font.GetFontName()).c_str(), SkTypeface::kNormal));
+
+  // Ensure we have enough space to print above and below the page to print
+  // headers.
+  string16 date = base::TimeFormatShortDateNumeric(Time::Now());
+  string16 title;
+  if (!header_footer_info.GetString(printing::kSettingHeaderFooterTitle,
+                                    &title)) {
+    NOTREACHED();
+  }
+
+  SkRect header_bounds;

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Put header_bounds below header_text

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  string16 header_text = date + title;
+  paint.measureText(header_text.c_str(), header_text.length() * sizeof(char16),
+                    &header_bounds, 0);
+
+  SkScalar text_height =
+      printing::kSettingHeaderFooterInterstice + header_bounds.height();
+
+  if (text_height > page_layout.margin_top)
+    return;
+
+  // Ensure we have enough space to print above and below the page to print
+  // footers.
+  string16 page_of_total_pages = base::IntToString16(page_number) +
+                                 UTF8ToUTF16("/") +
+                                 base::IntToString16(total_pages);
+  std::string url;
+  if (!header_footer_info.GetString(printing::kSettingHeaderFooterURL,
+                                    &url)) {
+    NOTREACHED();
+  }
+
+  SkRect footer_bounds;

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Put footer_bounds below footer_text

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  string16 footer_text = page_of_total_pages + UTF8ToUTF16(url);
+  paint.measureText(footer_text.c_str(), footer_text.length() * sizeof(char16),
+                    &footer_bounds, 0);
+
+  text_height =
+      printing::kSettingHeaderFooterInterstice + footer_bounds.height();
+
+  if (text_height > page_layout.margin_bottom)
+    return;
+
+  SkScalar segment_width = GetSegmentWidth(page_layout);
+  // Print the Date.

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Redundant comment.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  PrintHeaderFooterText(date, paint, canvas, printing::LEFT, printing::TOP,
+                        webkit_scale_factor, page_layout, segment_width, font,
+                        header_bounds.top());
+
+  // Print the title.

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Redundant comment.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  SkScalar date_width = paint.measureText(date.c_str(),
+                                          date.length() * sizeof(char16));
+  // Calculate the available title width. If the date string is not long
+  // enough, then, we increase the available space we have for the title.
+  // Assumes there is no header text to RIGHT of title.
+  SkScalar max_title_width = std::min(2 * segment_width,
+                                      2 * (segment_width - date_width) +
+                                          segment_width);
+  PrintHeaderFooterText(title, paint, canvas, printing::CENTER,
+                        printing::TOP, webkit_scale_factor, page_layout,
+                        max_title_width, font, header_bounds.top());
+
+  // Print the page numbers at the bottom right corner of page.

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Redundant comment.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  PrintHeaderFooterText(page_of_total_pages, paint, canvas, printing::RIGHT,
+                        printing::BOTTOM, webkit_scale_factor, page_layout,
+                        segment_width, font, footer_bounds.bottom());
+
+  // Print the URL.

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Redundant comment.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  GURL gurl(url);
+  SkScalar page_width = paint.measureText(
+      page_of_total_pages.c_str(),
+      page_of_total_pages.length() * sizeof(char16));
+
+  // Calculate the available URL width. We increase the available URL width
+  // if the |page_of_total_pages| string isn't long enough.
+  // Assumes no footer text being printed in the CENTER.
+  SkScalar max_url_width =
+      (page_layout.content_width + page_layout.margin_left +
+       page_layout.margin_right) * 3 / 4;
+  max_url_width = std::min(max_url_width,
+                           2 * (segment_width - page_width) + segment_width);
+  string16 url_elided = ui::ElideUrl(gurl, font,
+                                     ConvertPointsToPixelDouble(max_url_width),
+                                     std::string());
+  PrintHeaderFooterText(url_elided, paint, canvas, printing::LEFT,
+                        printing::BOTTOM, webkit_scale_factor, page_layout,
+                        max_url_width, font, footer_bounds.bottom());
+
+  // Restore the drawing area to draw in the content area.

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

Redundant comment.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+  static_cast<skia::VectorPlatformDeviceSkia*>(device)->setDrawingArea(
+      SkPDFDevice::kContent_DrawingArea);
+}
+#endif  // USE_SKIA
+
 PrepareFrameAndViewForPrint::PrepareFrameAndViewForPrint(
     const PrintMsg_Print_Params& print_params,
     WebFrame* frame,
     WebNode* node)
         : frame_(frame),
           web_view_(frame->view()),
           dpi_(static_cast<int>(print_params.dpi)),
           expected_pages_count_(0),
           use_browser_overlays_(true),
           finished_(false) {
@@ skipping 133 matching lines @@
     return;
   }
 
   WebFrame* pdf_frame = pdf_element.document().frame();
   scoped_ptr<PrepareFrameAndViewForPrint> prepare;
   if (!InitPrintSettingsAndPrepareFrame(pdf_frame, &pdf_element, &prepare)) {
     NOTREACHED() << "Failed to initialize print page settings";
     return;
   }
 
-  if (!UpdatePrintSettings(job_settings)) {
+  if (!UpdatePrintSettings(const_cast<DictionaryValue*>(&job_settings))) {
     DidFinishPrinting(FAIL_PRINT);
     return;
   }
 
   // Render Pages for printing.
   if (!RenderPagesForPrint(pdf_frame, &pdf_element, prepare.get()))
     DidFinishPrinting(FAIL_PRINT);
 }
 
 bool PrintWebViewHelper::GetPrintFrame(WebKit::WebFrame** frame) {
@@ skipping 37 matching lines @@
 void PrintWebViewHelper::OnPrintPreview(const DictionaryValue& settings) {
   DCHECK(is_preview_);
   print_preview_context_.OnPrintPreview();
 
   if (!InitPrintSettings(print_preview_context_.frame(),
                          print_preview_context_.node())) {
     NOTREACHED();
     return;
   }
 
-  if (!UpdatePrintSettings(settings)) {
+  if (!UpdatePrintSettings(const_cast<DictionaryValue*>(&settings))) {
     DidFinishPrinting(FAIL_PREVIEW);
     return;
   }
 
   if (print_pages_params_->params.preview_request_id != 0 &&
       old_print_pages_params_.get() &&
       PrintMsg_Print_Params_IsEqual(*old_print_pages_params_,
                                     *print_pages_params_)) {
     PrintHostMsg_DidPreviewDocument_Params preview_params;
     preview_params.reuse_existing_data = true;
@@ skipping 425 matching lines @@
     const DictionaryValue& job_settings,
     PrintMsg_Print_Params* params) {
   if (!job_settings.GetInteger(printing::kPreviewRequestID,
                                &(params->preview_request_id))) {
     NOTREACHED();
     return false;
   }
   return true;
 }
 
-bool PrintWebViewHelper::UpdatePrintSettings(
-    const DictionaryValue& job_settings) {
+bool PrintWebViewHelper::UpdatePrintSettings(DictionaryValue* job_settings) {
   PrintMsg_PrintPages_Params settings;
 
   Send(new PrintHostMsg_UpdatePrintSettings(routing_id(),
-      print_pages_params_->params.document_cookie, job_settings, &settings));
+       print_pages_params_->params.document_cookie, *job_settings, &settings));
 
   if (settings.params.dpi < kMinDpi || !settings.params.document_cookie)
     return false;
 
-  if (!UpdatePrintSettingsRequestId(job_settings, &(settings.params)))
+  if (!UpdatePrintSettingsRequestId(*job_settings, &(settings.params)))
     return false;
 
   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
+  // Getting Header and Footer settings.
+  bool display_header_footer = false;
+  if (!job_settings->GetBoolean(printing::kSettingHeaderFooter,
+                                &display_header_footer)) {
+    NOTREACHED();
+  }
+  if (!job_settings->Remove(printing::kSettingHeaderFooter, NULL))

[vandebo (ex-Chrome), 2011/08/03 19:00:05]

I don't think it's worth the effort to remove these settings.  The const cast is
much uglier than just passing on the unneeded settings.

[Aayush Kumar, 2011/08/04 18:25:04]

Done.

+    NOTREACHED();
+  print_pages_params_->params.display_header_footer = display_header_footer;
+
+  if (display_header_footer) {
+    string16 title;
+    std::string url;
+    if (!job_settings->GetString(printing::kSettingHeaderFooterTitle, &title) ||
+        !job_settings->GetString(printing::kSettingHeaderFooterURL, &url)) {
+      NOTREACHED();
+    }
+    header_footer_info_.reset(new DictionaryValue());
+    header_footer_info_->SetString(printing::kSettingHeaderFooterURL, url);
+    header_footer_info_->SetString(printing::kSettingHeaderFooterTitle, title);
+
+    if (!job_settings->Remove(printing::kSettingHeaderFooterTitle, NULL) ||
+        !job_settings->Remove(printing::kSettingHeaderFooterURL, NULL)) {
+      NOTREACHED();
+    }
+  }
+
   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
                                              settings.params.document_cookie));
   return true;
 }
 
 bool PrintWebViewHelper::GetPrintSettingsFromUser(WebKit::WebFrame* frame,
                                                   int expected_pages_count,
                                                   bool use_browser_overlays) {
   PrintHostMsg_ScriptedPrint_Params params;
   PrintMsg_PrintPages_Params print_settings;
@@ skipping 329 matching lines @@
 const gfx::Size&
 PrintWebViewHelper::PrintPreviewContext::GetPrintCanvasSize() const {
   return prep_frame_view_->GetPrintCanvasSize();
 }
 
 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
   prep_frame_view_.reset();
   metafile_.reset();
   rendered_pages_.clear();
 }