content/browser/renderer_host/pepper/pepper_print_settings_manager.cc

// Copyright (c) 2012 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 "content/browser/renderer_host/pepper/pepper_print_settings_manager.h"

#include "content/public/browser/browser_thread.h"
#include "ppapi/c/pp_errors.h"
#include "printing/printing_context.h"
#include "printing/units.h"

namespace content {

namespace {

#if defined(ENABLE_PRINTING)
// Print units conversion functions.
int32_t DeviceUnitsInPoints(int32_t device_units,
                            int32_t device_units_per_inch) {
  return printing::ConvertUnit(device_units, device_units_per_inch,
                               printing::kPointsPerInch);
}

PP_Size PrintSizeToPPPrintSize(const gfx::Size& print_size,
                               int32_t device_units_per_inch) {
  PP_Size result;
  result.width = DeviceUnitsInPoints(print_size.width(), device_units_per_inch);
  result.height = DeviceUnitsInPoints(print_size.height(),
                                      device_units_per_inch);
  return result;
}

PP_Rect PrintAreaToPPPrintArea(const gfx::Rect& print_area,
                               int32_t device_units_per_inch) {
  PP_Rect result;
  result.point.x = DeviceUnitsInPoints(print_area.origin().x(),
                                       device_units_per_inch);
  result.point.y = DeviceUnitsInPoints(print_area.origin().y(),
                                       device_units_per_inch);
  result.size = PrintSizeToPPPrintSize(print_area.size(),
                                       device_units_per_inch);
  return result;
}

PepperPrintSettingsManager::Result ComputeDefaultPrintSettings() {
  // This function should run on the UI thread because |PrintingContext| methods
  // call into platform APIs.
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  scoped_ptr<printing::PrintingContext> context(
  printing::PrintingContext::Create(std::string()));
  if (!context.get() ||
      context->UseDefaultSettings() != printing::PrintingContext::OK) {
    return PepperPrintSettingsManager::Result(PP_PrintSettings_Dev(),
                                              PP_ERROR_FAILED);
  }
  const printing::PrintSettings& print_settings = context->settings();
  const printing::PageSetup& page_setup =
       print_settings.page_setup_device_units();
  int device_units_per_inch = print_settings.device_units_per_inch();
  if (device_units_per_inch <= 0) {
    return PepperPrintSettingsManager::Result(PP_PrintSettings_Dev(),
                                              PP_ERROR_FAILED);
  }
  PP_PrintSettings_Dev settings;
  settings.printable_area = PrintAreaToPPPrintArea(
      page_setup.printable_area(), device_units_per_inch);
  settings.content_area = PrintAreaToPPPrintArea(
      page_setup.content_area(), device_units_per_inch);
  settings.paper_size = PrintSizeToPPPrintSize(
      page_setup.physical_size(), device_units_per_inch);
  settings.dpi = print_settings.dpi();

  // The remainder of the attributes are hard-coded to the defaults as set
  // elsewhere.
  settings.orientation = PP_PRINTORIENTATION_NORMAL;
  settings.grayscale = PP_FALSE;
  settings.print_scaling_option = PP_PRINTSCALINGOPTION_SOURCE_SIZE;

  // TODO(raymes): Should be computed in the same way as
  // |PluginInstance::GetPreferredPrintOutputFormat|.
  // |PP_PRINTOUTPUTFORMAT_PDF| is currently the only supported format though,
  // so just make it the default.
  settings.format = PP_PRINTOUTPUTFORMAT_PDF;
  return PepperPrintSettingsManager::Result(settings, PP_OK);
}
#else
PepperPrintSettingsManager::Result ComputeDefaultPrintSettings() {
  return PepperPrintSettingsManager::Result(PP_PrintSettings_Dev(),
                                            PP_ERROR_NOTSUPPORTED);
}
#endif

}  // namespace

void PepperPrintSettingsManagerImpl::GetDefaultPrintSettings(
    PepperPrintSettingsManager::Callback callback) {
  BrowserThread::PostTaskAndReplyWithResult(BrowserThread::UI, FROM_HERE,
      base::Bind(ComputeDefaultPrintSettings), callback);
}

}  // namespace content