/* gtkmm example Copyright (C) 2006 gtkmm development team
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "previewdialog.h"
#include "printformoperation.h"

#include <math.h>

PreviewDialog::PreviewDialog(
               PrintFormOperation* pfo,
               const Glib::RefPtr<Gtk::PrintOperationPreview>& preview,
               const Glib::RefPtr<Gtk::PrintContext>& print_ctx,
               Gtk::Window& parent)
  :
  m_pOperation(pfo),
  m_refPreview(preview),
  m_refPrintContext(print_ctx),
  m_SpinAdjustment(1, 100, 1), //Used to construct m_PageSpin
  m_PageSpin(m_SpinAdjustment, 1, 0),
  m_CloseButton(Gtk::Stock::CLOSE),
  m_Page(1),
  m_DpiX(0),
  m_DpiY(0)
{
  set_transient_for(parent);
  set_title("Preview");
  set_border_width(2);

  add(m_VBox);

  m_HBox.pack_start(m_PageSpin);
  m_HBox.pack_start(m_CloseButton, Gtk::PACK_SHRINK);
  m_VBox.pack_start(m_HBox, Gtk::PACK_SHRINK);

  m_DrawingArea.set_size_request(200, 300);
  m_VBox.pack_start(m_DrawingArea, Gtk::PACK_EXPAND_WIDGET);
  m_DrawingArea.set_double_buffered(false);


  m_refPreview->signal_ready().connect(
    sigc::mem_fun(*this, &PreviewDialog::on_popreview_ready));

  m_refPreview->signal_got_page_size().connect(
    sigc::mem_fun(*this, &PreviewDialog::on_popreview_got_page_size));

  m_DrawingArea.signal_realize().connect(
    sigc::mem_fun(*this, &PreviewDialog::on_drawing_area_realized));

  m_DrawingArea.signal_expose_event().connect(
    sigc::mem_fun(*this, &PreviewDialog::on_drawing_area_expose_event));

  m_CloseButton.signal_clicked().connect(
    sigc::mem_fun(*this, &PreviewDialog::on_close_clicked));

  m_PageSpin.signal_value_changed().connect(
    sigc::mem_fun(*this, &PreviewDialog::on_page_number_changed));

  show_all_children();
}

PreviewDialog::~PreviewDialog()
{
}

void PreviewDialog::on_drawing_area_realized()
{
  Glib::RefPtr<Gdk::Window> gdk_window = m_DrawingArea.get_window();
  if(gdk_window)
  {
    Cairo::RefPtr<Cairo::Context> cairo_ctx =
        gdk_window->create_cairo_context();

    if(m_refPrintContext)
      m_refPrintContext->set_cairo_context(cairo_ctx, 72, 72);
  }
}

void PreviewDialog::on_page_number_changed()
{
  m_Page = m_PageSpin.get_value_as_int();
  m_DrawingArea.queue_draw();
}

bool PreviewDialog::on_drawing_area_expose_event(GdkEventExpose* /* event */)
{
  Glib::RefPtr<Gdk::Window> window = m_DrawingArea.get_window();
  if(window)
    window->clear();

  if(m_refPreview)
    m_refPreview->render_page(m_Page - 1);

  return true;
}

void PreviewDialog::on_popreview_ready(const Glib::RefPtr<Gtk::PrintContext>&)
{
  m_PageSpin.set_range(1.0, m_pOperation->property_n_pages());

  m_DrawingArea.queue_draw();
}

void PreviewDialog::on_popreview_got_page_size(
                       const Glib::RefPtr<Gtk::PrintContext>& print_ctx,
                       const Glib::RefPtr<Gtk::PageSetup>& page_setup)
{
  Gtk::PaperSize paper_size = page_setup->get_paper_size();

  double width = paper_size.get_width(Gtk::UNIT_INCH);
  double height = paper_size.get_height(Gtk::UNIT_INCH);

  if(m_DrawingArea.is_realized()) //Avoid getting an odd allocation.
  {
    double dpi_x = m_DrawingArea.get_allocation().get_width() / width;
    double dpi_y = m_DrawingArea.get_allocation().get_height() / height;

    // We create a cairo context for the DrawingArea and then give that cairo
    // context to the PrintOperation's pango layout so that render_page() will
    // render into the drawing area.
    Cairo::RefPtr<Cairo::Context> cairo_ctx = m_DrawingArea.get_window()->create_cairo_context();

    if (fabs(dpi_x - m_DpiX) > 0.001 ||
        fabs(dpi_y - m_DpiY) > 0.001)
    {

      print_ctx->set_cairo_context(cairo_ctx, dpi_x, dpi_y);
      m_DpiX = dpi_x;
      m_DpiY = dpi_y;
    }

    if(m_pOperation)
    {
      Glib::RefPtr<Pango::Layout> layout = m_pOperation->get_pango_layout();
      if(layout)
        layout->update_from_cairo_context(cairo_ctx);
    }
  }
}

void PreviewDialog::on_hide()
{
  m_refPreview->end_preview();

  //We will not be using these anymore, so null the RefPtrs:
  m_refPreview.clear();
  m_refPrintContext.clear(); 
}

void PreviewDialog::on_close_clicked()
{
  hide();
}
