/* Printing

 *

 * GtkPrintOperation offers a simple API to support printing

 * in a cross-platform way.

 *

 */

#include <math.h>

#include <gtk/gtk.h>

#include "demo-common.h"

/* In points */

#define HEADER_HEIGHT (10*72/25.4)

#define HEADER_GAP (3*72/25.4)

typedef struct

{

  gchar *filename;

  gdouble font_size;

  gint lines_per_page;

  gchar **lines;

  gint num_lines;

  gint num_pages;

} PrintData;

static void

begin_print (GtkPrintOperation *operation,

	     GtkPrintContext   *context,

	     gpointer           user_data)

{

  PrintData *data = (PrintData *)user_data;

  char *contents;

  int i;

  double height;

  height = gtk_print_context_get_height (context) - HEADER_HEIGHT - HEADER_GAP;

  data->lines_per_page = floor (height / data->font_size);

  g_file_get_contents (data->filename, &contents, NULL, NULL);

  data->lines = g_strsplit (contents, "\n", 0);

  g_free (contents);

  i = 0;

  while (data->lines[i] != NULL)

    i++;

  data->num_lines = i;

  data->num_pages = (data->num_lines - 1) / data->lines_per_page + 1;

  gtk_print_operation_set_n_pages (operation, data->num_pages);

}

static void

draw_page (GtkPrintOperation *operation,

	   GtkPrintContext   *context,

	   gint               page_nr,

	   gpointer           user_data)

{

  PrintData *data = (PrintData *)user_data;

  cairo_t *cr;

  PangoLayout *layout;

  gint text_width, text_height;

  gdouble width;

  gint line, i;

  PangoFontDescription *desc;

  gchar *page_str;

  cr = gtk_print_context_get_cairo_context (context);

  width = gtk_print_context_get_width (context);

  cairo_rectangle (cr, 0, 0, width, HEADER_HEIGHT);

  cairo_set_source_rgb (cr, 0.8, 0.8, 0.8);

  cairo_fill_preserve (cr);

  cairo_set_source_rgb (cr, 0, 0, 0);

  cairo_set_line_width (cr, 1);

  cairo_stroke (cr);

  layout = gtk_print_context_create_pango_layout (context);

  desc = pango_font_description_from_string ("sans 14");

  pango_layout_set_font_description (layout, desc);

  pango_font_description_free (desc);

  pango_layout_set_text (layout, data->filename, -1);

  pango_layout_get_pixel_size (layout, &text_width, &text_height);

  if (text_width > width)

    {

      pango_layout_set_width (layout, width);

      pango_layout_set_ellipsize (layout, PANGO_ELLIPSIZE_START);

      pango_layout_get_pixel_size (layout, &text_width, &text_height);

    }

  cairo_move_to (cr, (width - text_width) / 2,  (HEADER_HEIGHT - text_height) / 2);

  pango_cairo_show_layout (cr, layout);

  page_str = g_strdup_printf ("%d/%d", page_nr + 1, data->num_pages);

  pango_layout_set_text (layout, page_str, -1);

  g_free (page_str);

  pango_layout_set_width (layout, -1);

  pango_layout_get_pixel_size (layout, &text_width, &text_height);

  cairo_move_to (cr, width - text_width - 4, (HEADER_HEIGHT - text_height) / 2);

  pango_cairo_show_layout (cr, layout);

  g_object_unref (layout);

  layout = gtk_print_context_create_pango_layout (context);

  desc = pango_font_description_from_string ("monospace");

  pango_font_description_set_size (desc, data->font_size * PANGO_SCALE);

  pango_layout_set_font_description (layout, desc);

  pango_font_description_free (desc);

  cairo_move_to (cr, 0, HEADER_HEIGHT + HEADER_GAP);

  line = page_nr * data->lines_per_page;

  for (i = 0; i < data->lines_per_page && line < data->num_lines; i++)

    {

      pango_layout_set_text (layout, data->lines[line], -1);

      pango_cairo_show_layout (cr, layout);

      cairo_rel_move_to (cr, 0, data->font_size);

      line++;

    }

  g_object_unref (layout);

}

static void

end_print (GtkPrintOperation *operation,

	   GtkPrintContext   *context,

	   gpointer           user_data)

{

  PrintData *data = (PrintData *)user_data;

  g_free (data->filename);

  g_strfreev (data->lines);

  g_free (data);

}

GtkWidget *

do_printing (GtkWidget *do_widget)

{

  GtkPrintOperation *operation;

  GtkPrintSettings *settings;

  PrintData *data;

  gchar *uri, *ext;

  const gchar *dir;

  GError *error = NULL;

  operation = gtk_print_operation_new ();

  data = g_new0 (PrintData, 1);

  data->filename = demo_find_file ("printing.c", NULL);

  data->font_size = 12.0;

  g_signal_connect (G_OBJECT (operation), "begin-print",

		    G_CALLBACK (begin_print), data);

  g_signal_connect (G_OBJECT (operation), "draw-page",

		    G_CALLBACK (draw_page), data);

  g_signal_connect (G_OBJECT (operation), "end-print",

		    G_CALLBACK (end_print), data);

  gtk_print_operation_set_use_full_page (operation, FALSE);

  gtk_print_operation_set_unit (operation, GTK_UNIT_POINTS);

  gtk_print_operation_set_embed_page_setup (operation, TRUE);

  settings = gtk_print_settings_new ();

  dir = g_get_user_special_dir (G_USER_DIRECTORY_DOCUMENTS);

  if (dir == NULL)

    dir = g_get_home_dir ();

  if (g_strcmp0 (gtk_print_settings_get (settings, GTK_PRINT_SETTINGS_OUTPUT_FILE_FORMAT), "ps") == 0)

    ext = ".ps";

  else if (g_strcmp0 (gtk_print_settings_get (settings, GTK_PRINT_SETTINGS_OUTPUT_FILE_FORMAT), "svg") == 0)

    ext = ".svg";

  else

    ext = ".pdf";

  uri = g_strconcat ("file://", dir, "/", "gtk-demo", ext, NULL);

  gtk_print_settings_set (settings, GTK_PRINT_SETTINGS_OUTPUT_URI, uri);

  gtk_print_operation_set_print_settings (operation, settings);

  gtk_print_operation_run (operation, GTK_PRINT_OPERATION_ACTION_PRINT_DIALOG, GTK_WINDOW (do_widget), &error);

  g_object_unref (operation);

  g_object_unref (settings);

  g_free (uri);

  if (error)

    {

      GtkWidget *dialog;

      dialog = gtk_message_dialog_new (GTK_WINDOW (do_widget),

				       GTK_DIALOG_DESTROY_WITH_PARENT,

				       GTK_MESSAGE_ERROR,

				       GTK_BUTTONS_CLOSE,

				       "%s", error->message);

      g_error_free (error);

      g_signal_connect (dialog, "response",

			G_CALLBACK (gtk_widget_destroy), NULL);

      gtk_widget_show (dialog);

    }

  return NULL;

}