/* Dia -- an diagram creation/manipulation program
 * Copyright (C) 1998 Alexander Larsson
 *
 * xfig-export.c: xfig export filter for dia
 * Copyright (C) 2001 Lars Clausen
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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 "config.h"

#include <glib/gi18n-lib.h>

#include <stdio.h>
/* Information used here is taken from the FIG Format 3.2 specification
   <URL:http://www.xfig.org/userman/fig-format.html>
   Some items left unspecified in the specifications are taken from the
   XFig source v. 3.2.3c
 */

#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <errno.h>
#include <locale.h>

#include <glib.h>
#include <glib/gstdio.h>

#include "message.h"
#include "geometry.h"
#include "diarenderer.h"
#include "filter.h"
#include "object.h"
#include "properties.h"
#include "dia_image.h"
#include "group.h"
#include "diatransformrenderer.h"
#include "dia-layer.h"

#include "xfig.h"

#define WARNING_OUT_OF_COLORS 0
#define MAX_WARNING 1

#define DTOSTR_BUF_SIZE G_ASCII_DTOSTR_BUF_SIZE
#define xfig_dtostr(buf,d) \
	g_ascii_formatd(buf, sizeof(buf), "%f", d)


#define DIA_XFIG_TYPE_RENDERER dia_xfig_renderer_get_type ()
G_DECLARE_FINAL_TYPE (DiaXfigRenderer, dia_xfig_renderer, DIA_XFIG, RENDERER, DiaRenderer)

struct _DiaXfigRenderer {
  DiaRenderer parent_instance;

  FILE *file;

  int depth;

  double linewidth;
  DiaLineCaps capsmode;
  DiaLineJoin joinmode;
  DiaLineStyle stylemode;
  double dashlength;
  DiaFillStyle fillmode;
  DiaFont *font;
  double fontheight;

  gboolean color_pass;
  Color user_colors[512];
  int max_user_color;

  char *warnings[MAX_WARNING];
};

G_DEFINE_TYPE (DiaXfigRenderer, dia_xfig_renderer, DIA_TYPE_RENDERER)

enum {
  PROP_0,
  PROP_FONT,
  PROP_FONT_HEIGHT,
  LAST_PROP
};


/* check whether there exists an arrow head */
static int
hasArrow (Arrow *arrow)
{
  return (!arrow || ARROW_NONE == arrow->type) ? 0 : 1;
}


static void
dia_xfig_renderer_finalize (GObject *object)
{
  DiaXfigRenderer *self = DIA_XFIG_RENDERER (object);

  g_clear_object (&self->font);

  G_OBJECT_CLASS (dia_xfig_renderer_parent_class)->finalize (object);
}


static void
dia_xfig_renderer_set_font (DiaXfigRenderer *self,
                            DiaFont         *font,
                            double           height)
{
  g_set_object (&self->font, font);
  self->fontheight = height;
}


static void
dia_xfig_renderer_set_property (GObject      *object,
                                guint         property_id,
                                const GValue *value,
                                GParamSpec   *pspec)
{
  DiaXfigRenderer *self = DIA_XFIG_RENDERER (object);

  switch (property_id) {
    case PROP_FONT:
      dia_xfig_renderer_set_font (self,
                                  g_value_get_object (value),
                                  self->fontheight);
      break;
    case PROP_FONT_HEIGHT:
      dia_xfig_renderer_set_font (self,
                                  self->font,
                                  g_value_get_double (value));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
  }
}


static void
dia_xfig_renderer_get_property (GObject    *object,
                                guint       property_id,
                                GValue     *value,
                                GParamSpec *pspec)
{
  DiaXfigRenderer *self = DIA_XFIG_RENDERER (object);

  switch (property_id) {
    case PROP_FONT:
      g_value_set_object (value, self->font);
      break;
    case PROP_FONT_HEIGHT:
      g_value_set_double (value, self->fontheight);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
      break;
  }
}


/* Helper functions */
static void
figWarn (DiaXfigRenderer *renderer, int warning)
{
  if (renderer->warnings[warning]) {
    message_warning ("%s", renderer->warnings[warning]);
    renderer->warnings[warning] = NULL;
  }
}


static int
figLineStyle (DiaXfigRenderer *renderer)
{
  switch (renderer->stylemode) {
    case DIA_LINE_STYLE_SOLID:
      return 0;
    case DIA_LINE_STYLE_DASHED:
      return 1;
    case DIA_LINE_STYLE_DASH_DOT:
      return 3;
    case DIA_LINE_STYLE_DASH_DOT_DOT:
      return 4;
    case DIA_LINE_STYLE_DOTTED:
      return 2;
    case DIA_LINE_STYLE_DEFAULT:
    default:
      return 0;
  }
}


static int
figLineWidth (DiaXfigRenderer *renderer)
{
  int width = 0;
  /* Minimal line width in fig diagrams. */
  if (renderer->linewidth <= 0.03175) {
    width = 1;
  } else {
    width = (int) ((renderer->linewidth / 2.54) * 80.0);
  }
  return width;
}


/* Must be called before outputting anything that uses this color,
   in order to output a color pseudo object.
   The color pseudo object even must be placed first in the xfig file.
 */
static void
figCheckColor (DiaXfigRenderer *renderer, Color *color)
{
  int i;

  for (i = 0; i < FIG_MAX_DEFAULT_COLORS; i++) {
    if (dia_colour_equals (color, &fig_default_colors[i])) {
      return;
    }
  }

  for (i = 0; i < renderer->max_user_color; i++) {
    if (dia_colour_equals (color, &renderer->user_colors[i])) {
      return;
    }
  }

  if (renderer->max_user_color == FIG_MAX_USER_COLORS) {
    figWarn(renderer, WARNING_OUT_OF_COLORS);
    return;
  }

  renderer->user_colors[renderer->max_user_color] = *color;
  fprintf (renderer->file,
           "0 %d #%02x%02x%02x\n",
           renderer->max_user_color + FIG_MAX_DEFAULT_COLORS,
           (int) (color->red * 255),
           (int) (color->green * 255),
           (int) (color->blue * 255));
  renderer->max_user_color++;
}


static int
figColor (DiaXfigRenderer *renderer, Color *color)
{
  int i;

  for (i = 0; i < FIG_MAX_DEFAULT_COLORS; i++) {
    if (dia_colour_equals (color, &fig_default_colors[i])) {
      return i;
    }
  }

  for (i = 0; i < renderer->max_user_color; i++) {
    if (dia_colour_equals (color, &renderer->user_colors[i])) {
      return i + FIG_MAX_DEFAULT_COLORS;
    }
  }

  return 0;
}


static double
figCoord (DiaXfigRenderer *renderer, double coord)
{
  return (coord / 2.54) * 1200.0;
}


static double
figAltCoord (DiaXfigRenderer *renderer, double coord)
{
  return (coord / 2.54) * 80.0;
}


static int
figDepth (DiaXfigRenderer *renderer)
{
  return renderer->depth;
}


static double
figDashLength (DiaXfigRenderer *renderer)
{
  return figAltCoord (renderer, renderer->dashlength);
}


static int
figJoinStyle (DiaXfigRenderer *renderer)
{
  return renderer->joinmode;
}


static int
figCapsStyle (DiaXfigRenderer *renderer)
{
  return renderer->capsmode;
}


static int
figAlignment (DiaXfigRenderer *renderer, int alignment)
{
  return alignment;
}


static int
figFont (DiaXfigRenderer *renderer)
{
  int i;
  const char *legacy_name;

  /* FIXME: this is broken */
  legacy_name = dia_font_get_legacy_name (renderer->font);
  for (i = 0; fig_fonts[i] != NULL; i++) {
    if (!g_strcmp0 (legacy_name, fig_fonts[i])) {
      return i;
    }
  }

  return -1;
}


static double
figFontSize (DiaXfigRenderer *renderer)
{
  return (renderer->fontheight / 2.54) * 72.27;
}


static guchar *
figText (DiaXfigRenderer *renderer, const guchar *text)
{
  int i, j;
  int len = strlen ((char *) text);
  int newlen = len;
  char *returntext;

  for (i = 0; i < len; i++) {
    if (text[i] > 127) {
      newlen += 3;
    } else if ('\\'==text[i]) {
      newlen += 1;
    }
  }

  returntext = g_new0 (char, newlen + 1);
  j = 0;

  for (i = 0; i < len; i++, j++) {
    if (text[i] > 127) {
      sprintf (&returntext[j], "\\%03o", text[i]);
      j += 3;
    } else if ('\\'==text[i]) { /* backslash must be quoted in xfig */
      returntext[j++] = '\\';
      returntext[j]   = '\\';
    } else {
      returntext[j] = text[i];
    }
  }
  returntext[j] = 0;
  return (guchar *) returntext;
}


static void
figArrow (DiaXfigRenderer *renderer, Arrow *arrow, double line_width)
{
  int type, style;
  char lw_buf[DTOSTR_BUF_SIZE];
  char aw_buf[DTOSTR_BUF_SIZE];
  char al_buf[DTOSTR_BUF_SIZE];

  switch (arrow->type) {
    case ARROW_NONE:
      return;
    case ARROW_LINES:             /* {open arrow} */
      type = 0; style = 0; break;
    case ARROW_UNFILLED_TRIANGLE:
    case ARROW_HOLLOW_TRIANGLE:   /* {blanked arrow} */
      type = 1; style = 0; break;
    case ARROW_FILLED_TRIANGLE:   /* {filled arrow} */
      type = 1; style = 1; break;
    case ARROW_HOLLOW_DIAMOND:
      type = 3; style = 0; break;
    case ARROW_FILLED_DIAMOND:
      type = 3; style = 1; break;
    case ARROW_HALF_HEAD:
    case ARROW_SLASHED_CROSS:
    case ARROW_FILLED_ELLIPSE:
    case ARROW_HOLLOW_ELLIPSE:
    case ARROW_DOUBLE_HOLLOW_TRIANGLE:
    case ARROW_DOUBLE_FILLED_TRIANGLE:
    case ARROW_FILLED_DOT:
    case ARROW_DIMENSION_ORIGIN:
    case ARROW_BLANKED_DOT:
    case ARROW_FILLED_BOX:
    case ARROW_BLANKED_BOX:
    case ARROW_SLASH_ARROW:
    case ARROW_INTEGRAL_SYMBOL:
    case ARROW_CROW_FOOT:
    case ARROW_CROSS:
    case ARROW_ROUNDED:
    case ARROW_HALF_DIAMOND:
    case ARROW_OPEN_ROUNDED:
    case ARROW_FILLED_DOT_N_TRIANGLE:
    case ARROW_ONE_OR_MANY:
    case ARROW_NONE_OR_MANY:
    case ARROW_ONE_OR_NONE:
    case ARROW_ONE_EXACTLY:
    case ARROW_BACKSLASH:
    case ARROW_THREE_DOTS:
    default:
      message_warning (_("Fig format has no equivalent of arrow style %s; using simple arrow.\n"),
                       arrow_get_name_from_type (arrow->type));
      /* Notice fallthrough */
    case ARROW_FILLED_CONCAVE:
      type = 2; style = 1; break;
    case ARROW_BLANKED_CONCAVE:
      type = 2; style = 0; break;
    case MAX_ARROW_TYPE:
      g_return_if_reached ();
  }

  fprintf (renderer->file,
           "  %d %d %s %s %s\n",
           type,
           style,
           xfig_dtostr (lw_buf, figAltCoord (renderer, line_width)),
           xfig_dtostr (aw_buf, figCoord (renderer, arrow->width)),
           xfig_dtostr (al_buf, figCoord (renderer, arrow->length)) );
}


static void
begin_render (DiaRenderer *self, const DiaRectangle *update)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  if (renderer->color_pass) {
    /* Set up warnings */
    renderer->warnings[WARNING_OUT_OF_COLORS] =
      _("No more user-definable colors - using black");
    renderer->max_user_color = 0;
  }

  renderer->depth = 0;

  renderer->linewidth = 0;
  renderer->capsmode = 0;
  renderer->joinmode = 0;
  renderer->stylemode = 0;
  renderer->dashlength = 0;
  renderer->fillmode = 0;
  renderer->font = NULL;
  renderer->fontheight = 1;
}


static void
end_render (DiaRenderer *renderer)
{
}


static void
set_linewidth (DiaRenderer *self, double linewidth)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  renderer->linewidth = linewidth;
}


static void
set_linecaps (DiaRenderer *self, DiaLineCaps mode)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  renderer->capsmode = mode;
}


static void
set_linejoin (DiaRenderer *self, DiaLineJoin mode)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  renderer->joinmode = mode;
}


static void
set_linestyle (DiaRenderer *self, DiaLineStyle mode, double dash_length)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  renderer->stylemode = mode;
  renderer->dashlength = dash_length;
}


static void
set_fillstyle (DiaRenderer *self, DiaFillStyle mode)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  renderer->fillmode = mode;
}


static void
draw_line (DiaRenderer *self,
           Point       *start,
           Point       *end,
           Color       *color)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  fprintf (renderer->file,
           "2 1 %d %d %d 0 %d 0 -1 %s %d %d 0 0 0 2\n"
           "\t%d %d %d %d\n",
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (d_buf, figDashLength (renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer),
           (int) figCoord (renderer, start->x),
           (int) figCoord (renderer, start->y),
           (int) figCoord (renderer, end->x),
           (int) figCoord (renderer, end->y));
}


static void
draw_line_with_arrows (DiaRenderer *self,
                       Point       *start,
                       Point       *end,
                       double       line_width,
                       Color       *color,
                       Arrow       *start_arrow,
                       Arrow       *end_arrow)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  fprintf (renderer->file,
           "2 1 %d %d %d 0 %d 0 -1 %s %d %d 0 %d %d 2\n",
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (d_buf, figDashLength(renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer),
           hasArrow (end_arrow),
           hasArrow (start_arrow));

  if (hasArrow (end_arrow)) {
    figArrow (renderer, end_arrow, line_width);
  }

  if (hasArrow (start_arrow)) {
    figArrow (renderer, start_arrow, line_width);
  }

  fprintf (renderer->file,
           "\t%d %d %d %d\n",
           (int) figCoord (renderer, start->x),
           (int) figCoord (renderer, start->y),
           (int) figCoord (renderer, end->x),
           (int) figCoord (renderer, end->y));
}


static void
draw_polyline (DiaRenderer *self,
               Point       *points,
               int          num_points,
               Color       *color)
{
  int i;
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  fprintf (renderer->file,
           "2 1 %d %d %d 0 %d 0 -1 %s %d %d 0 0 0 %d\n",
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (d_buf, figDashLength (renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer),
           num_points);

  fprintf (renderer->file, "\t");
  for (i = 0; i < num_points; i++) {
    fprintf (renderer->file,
             "%d %d ",
             (int) figCoord (renderer, points[i].x),
             (int) figCoord (renderer, points[i].y));
  }
  fprintf (renderer->file, "\n");
}


static void
draw_polyline_with_arrows (DiaRenderer *self,
                           Point       *points,
                           int          num_points,
                           double       line_width,
                           Color       *color,
                           Arrow       *start_arrow,
                           Arrow       *end_arrow)
{
  int i;
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  fprintf (renderer->file,
           "2 1 %d %d %d 0 %d 0 -1 %s %d %d 0 %d %d %d\n",
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (d_buf, figDashLength (renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer),
           hasArrow (end_arrow),
           hasArrow (start_arrow),
           num_points);

  if (hasArrow (end_arrow)) {
    figArrow (renderer, end_arrow, line_width);
  }

  if (hasArrow (start_arrow)) {
    figArrow (renderer, start_arrow, line_width);
  }

  fprintf (renderer->file, "\t");
  for (i = 0; i < num_points; i++) {
    fprintf (renderer->file,
             "%d %d ",
             (int) figCoord (renderer, points[i].x),
             (int) figCoord (renderer, points[i].y));
  }
  fprintf (renderer->file, "\n");
}


static void
draw_polygon (DiaRenderer *self,
              Point       *points,
              int          num_points,
              Color       *fill,
              Color       *stroke)
{
  int i;
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    if (stroke) {
      figCheckColor (renderer, stroke);
    }
    if (fill) {
      figCheckColor (renderer, fill);
    }
    return;
  }

  fprintf (renderer->file,
           "2 3 %d %d %d %d %d 0 %d %s %d %d 0 0 0 %d\n",
           figLineStyle (renderer),
           stroke ? figLineWidth (renderer) : 0,
           stroke ? figColor (renderer, stroke) : 0,
           fill ? figColor (renderer, fill) : 0,
           figDepth (renderer),
           fill ? 20 : -1,
           xfig_dtostr (d_buf, figDashLength (renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer), num_points + 1);

  fprintf (renderer->file, "\t");
  for (i = 0; i < num_points; i++) {
    fprintf (renderer->file,
             "%d %d ",
             (int) figCoord (renderer, points[i].x),
             (int) figCoord (renderer, points[i].y));
  }
  fprintf (renderer->file,
           "%d %d\n",
           (int) figCoord (renderer, points[0].x),
           (int) figCoord (renderer, points[0].y));
}


static void
draw_rect (DiaRenderer *self,
           Point       *ul_corner,
           Point       *lr_corner,
           Color       *fill,
           Color       *stroke)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    if (stroke) {
      figCheckColor (renderer, stroke);
    }
    if (fill) {
      figCheckColor (renderer, fill);
    }
    return;
  }

  fprintf (renderer->file,
           "2 3 %d %d %d %d %d -1 %d %s %d %d 0 0 0 5\n"
           "\t%d %d %d %d %d %d %d %d %d %d\n",
           figLineStyle (renderer),
           stroke ? figLineWidth (renderer) : 0,
           stroke ? figColor (renderer, stroke) : 0,
           fill ? figColor (renderer, fill) : 0,
           figDepth (renderer),
           fill ? 20 : -1,
           xfig_dtostr (d_buf, figDashLength (renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer),
           (int) figCoord (renderer, ul_corner->x),
           (int) figCoord (renderer, ul_corner->y),
           (int) figCoord (renderer, lr_corner->x),
           (int) figCoord (renderer, ul_corner->y),
           (int) figCoord (renderer, lr_corner->x),
           (int) figCoord (renderer, lr_corner->y),
           (int) figCoord (renderer, ul_corner->x),
           (int) figCoord (renderer, lr_corner->y),
           (int) figCoord (renderer, ul_corner->x),
           (int) figCoord (renderer, ul_corner->y));
}


static void
draw_arc (DiaRenderer *self,
          Point       *center,
          double       width,
          double       height,
          double       angle1,
          double       angle2,
          Color       *color)
{
  Point first, second, last;
  int direction = angle2 > angle1 ? 1 : 0; /* Dia not always gives counterclockwise */
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char dl_buf[DTOSTR_BUF_SIZE];
  char cx_buf[DTOSTR_BUF_SIZE];
  char cy_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  fprintf (renderer->file,
           "#draw_arc center=(%g,%g) radius=%g angle1=%g° angle2=%g°\n",
           center->x,
           center->y,
           (width + height) / 4.0,
           angle1,
           angle2);

  /* adjust to radians */
  angle1 *= (M_PI / 180.0);
  angle2 *= (M_PI / 180.0);

  first = *center;
  first.x += (width / 2.0) * cos (angle1);
  first.y -= (height / 2.0) * sin (angle1);

  second = *center;
  second.x += (width / 2.0) * cos ((angle1 + angle2) / 2.0);
  second.y -= (height / 2.0) * sin ((angle1 + angle2) / 2.0);

  last = *center;
  last.x += (width / 2.0) * cos (angle2);
  last.y -= (height / 2.0) * sin (angle2);

  fprintf (renderer->file,
           "5 1 %d %d %d %d %d 0 -1 %s %d %d 0 0 %s %s %d %d %d %d %d %d\n",
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (dl_buf, figDashLength (renderer)),
           figCapsStyle (renderer),
           direction,
           xfig_dtostr (cx_buf, figCoord (renderer, center->x)),
           xfig_dtostr (cy_buf, figCoord (renderer, center->y)),
           (int) figCoord (renderer, first.x),
           (int) figCoord (renderer, first.y),
           (int) figCoord (renderer, second.x),
           (int) figCoord (renderer, second.y),
           (int) figCoord (renderer, last.x),
           (int) figCoord (renderer, last.y));
}


/* once more copied from lib/diarenderer.c (see also objects/standard/arc.c */
static gboolean
is_right_hand (const Point *a, const Point *b, const Point *c)
{
  Point dot1, dot2;

  dot1 = *a;
  point_sub (&dot1, c);
  point_normalize (&dot1);
  dot2 = *b;
  point_sub (&dot2, c);
  point_normalize (&dot2);
  return point_cross (&dot1, &dot2) > 0;
}


static void
draw_arc_with_arrows (DiaRenderer *self,
                      Point       *startpoint,
                      Point       *endpoint,
                      Point       *midpoint,
                      double       line_width,
                      Color       *color,
                      Arrow       *start_arrow,
                      Arrow       *end_arrow)
{
  Point center;
  int direction = 0;
  double radius = -1.0;
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER(self);
  char dl_buf[DTOSTR_BUF_SIZE];
  char cx_buf[DTOSTR_BUF_SIZE];
  char cy_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  center.x = 0.0;
  center.y = 0.0;
  direction = is_right_hand (startpoint, midpoint, endpoint) ? 0 : 1;
  if (!three_point_circle (startpoint, midpoint, endpoint, &center, &radius)) {
    message_warning ("xfig: arc conversion failed");
  }

  fprintf (renderer->file,
           "#draw_arc_with_arrows center=(%g,%g) radius=%g\n"
           "5 1 %d %d %d %d %d 0 -1 %s %d %d %d %d %s %s %d %d %d %d %d %d\n",
           center.x,
           center.y,
           radius,
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (dl_buf, figDashLength (renderer)),
           figCapsStyle (renderer),
           direction,
           hasArrow (end_arrow),
           hasArrow (start_arrow),
           xfig_dtostr (cx_buf, figCoord (renderer, center.x)),
           xfig_dtostr (cy_buf, figCoord (renderer, center.y)),
           (int) figCoord (renderer, startpoint->x),
           (int) figCoord (renderer, startpoint->y),
           (int) figCoord (renderer, midpoint->x),
           (int) figCoord (renderer, midpoint->y),
           (int) figCoord (renderer, endpoint->x),
           (int) figCoord (renderer, endpoint->y));

  if (hasArrow (end_arrow)) {
    figArrow (renderer, end_arrow, line_width);
  }

  if (hasArrow (start_arrow)) {
    figArrow (renderer, start_arrow, line_width);
  }
}


static void
fill_arc (DiaRenderer *self,
          Point       *center,
          double       width,
          double       height,
          double       angle1,
          double       angle2,
          Color       *color)
{
  Point first, second, last;
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER(self);
  char dl_buf[DTOSTR_BUF_SIZE];
  char cx_buf[DTOSTR_BUF_SIZE];
  char cy_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  fprintf (renderer->file,
           "#fill_arc center=(%g,%g) radius=%g angle1=%g° angle2=%g°\n",
           center->x,
           center->y,
           (width + height) / 4.0,
           angle1,
           angle2);
  /* adjust to radians */
  angle1 *= (M_PI / 180.0);
  angle2 *= (M_PI / 180.0);

  first = *center;
  first.x += (width / 2.0) * cos (angle1);
  first.y -= (height / 2.0) * sin (angle1);

  second = *center;
  second.x += (width / 2.0) * cos ((angle1 + angle2) / 2.0);
  second.y -= (height / 2.0) * sin ((angle1 + angle2) / 2.0);

  last = *center;
  last.x += (width / 2.0) * cos (angle2);
  last.y -= (height / 2.0) * sin (angle2);

  fprintf (renderer->file,
           "5 2 %d %d %d %d %d 20 0 %s %d 1 0 0 %s %s %d %d %d %d %d %d\n",
           figLineStyle (renderer),
           figLineWidth (renderer),
           figColor (renderer, color),
           figColor (renderer, color),
           figDepth (renderer),
           xfig_dtostr (dl_buf, figDashLength (renderer)),
           figCapsStyle (renderer),
           xfig_dtostr (cx_buf, figCoord (renderer, center->x)),
           xfig_dtostr (cy_buf, figCoord (renderer, center->y)),
           (int) figCoord (renderer, first.x),
           (int) figCoord (renderer, first.y),
           (int) figCoord (renderer, second.x),
           (int) figCoord (renderer, second.y),
           (int) figCoord (renderer, last.x),
           (int) figCoord (renderer, last.y));
}


static void
draw_ellipse (DiaRenderer *self,
              Point       *center,
              double       width,
              double       height,
              Color       *fill,
              Color       *stroke)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    if (stroke) {
      figCheckColor (renderer, stroke);
    }
    if (fill) {
      figCheckColor (renderer, fill);
    }
    return;
  }

  fprintf (renderer->file,
           "1 1 %d %d %d %d %d 0 %d %s 1 0.0 %d %d %d %d 0 0 0 0\n",
           figLineStyle (renderer),
           stroke ? figLineWidth (renderer) : 0,
           stroke ? figColor (renderer, stroke) : 0,
           fill ? figColor (renderer, fill) : 0,
           figDepth (renderer),
           fill ? 20 : -1,
           xfig_dtostr (d_buf, figDashLength (renderer)),
           (int) figCoord (renderer, center->x),
           (int) figCoord (renderer, center->y),
           (int) figCoord (renderer, width / 2),
           (int) figCoord (renderer, height / 2));
}


static void
draw_bezier (DiaRenderer *self,
             BezPoint    *points,
             int          numpoints,
             Color       *color)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  DIA_RENDERER_CLASS (dia_xfig_renderer_parent_class)->draw_bezier (self,
                                                                    points,
                                                                    numpoints,
                                                                    color);
}


static void
draw_bezier_with_arrows (DiaRenderer *self,
                         BezPoint    *points,
                         int          numpoints,
                         double       line_width,
                         Color       *color,
                         Arrow       *start_arrow,
                         Arrow       *end_arrow)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  if (renderer->color_pass) {
    figCheckColor (renderer, color);
    return;
  }

  DIA_RENDERER_CLASS (dia_xfig_renderer_parent_class)->draw_bezier_with_arrows (self,
                                                                                points,
                                                                                numpoints,
                                                                                line_width,
                                                                                color,
                                                                                start_arrow,
                                                                                end_arrow);
}


static void
draw_beziergon (DiaRenderer *self,
                BezPoint    *points,
                int          numpoints,
                Color       *fill,
                Color       *stroke)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);

  if (renderer->color_pass) {
    if (fill) {
      figCheckColor (renderer, fill);
    }
    if (stroke) {
      figCheckColor (renderer, stroke);
    }
    return;
  }

  DIA_RENDERER_CLASS (dia_xfig_renderer_parent_class)->draw_beziergon (self,
                                                                       points,
                                                                       numpoints,
                                                                       fill,
                                                                       stroke);
}


static void
draw_string (DiaRenderer  *self,
             const char   *text,
             Point        *pos,
             DiaAlignment  alignment,
             Color        *color)
{
  guchar *figtext = NULL;
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    figCheckColor(renderer, color);
    return;
  }

  figtext = figText (renderer, (unsigned char *) text);
  /* xfig texts are specials */
  fprintf (renderer->file,
           "4 %d %d %d 0 %d %s 0.0 6 0.0 0.0 %d %d %s\\001\n",
           figAlignment (renderer, alignment),
           figColor (renderer, color),
           figDepth (renderer),
           figFont (renderer),
           xfig_dtostr (d_buf, figFontSize (renderer)),
           (int) figCoord (renderer, pos->x),
           (int) figCoord (renderer, pos->y),
           figtext);
  g_clear_pointer (&figtext, g_free);
}


static void
draw_image (DiaRenderer *self,
            Point       *point,
            double       width,
            double       height,
            DiaImage    *image)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER (self);
  char d_buf[DTOSTR_BUF_SIZE];

  if (renderer->color_pass) {
    return;
  }

  fprintf (renderer->file,
           "2 5 %d 0 -1 0 %d 0 -1 %s %d %d 0 0 0 5\n"
           "\t0 %s\n"
           "\t%d %d %d %d %d %d %d %d %d %d\n",
           figLineStyle (renderer),
           figDepth (renderer),
           xfig_dtostr (d_buf, figDashLength (renderer)),
           figJoinStyle (renderer),
           figCapsStyle (renderer),
           dia_image_filename (image),
           (int) figCoord (renderer, point->x),
           (int) figCoord (renderer, point->y),
           (int) figCoord (renderer, point->x+width),
           (int) figCoord (renderer, point->y),
           (int) figCoord (renderer, point->x+width),
           (int) figCoord (renderer, point->y+height),
           (int) figCoord (renderer, point->x),
           (int) figCoord (renderer, point->y+height),
           (int) figCoord (renderer, point->x),
           (int) figCoord (renderer, point->y));
}


static void
draw_object (DiaRenderer *self,
             DiaObject   *object,
             DiaMatrix   *matrix)
{
  DiaXfigRenderer *renderer = DIA_XFIG_RENDERER(self);

  if (renderer->color_pass) {
    /* color pass does not need transformation */
    dia_object_draw (object, DIA_RENDERER (renderer));
  } else {
    fprintf (renderer->file, "6 0 0 0 0\n");
    if (matrix) {
      DiaRenderer *tr = dia_transform_renderer_new (self);

      dia_renderer_draw_object (tr, object, matrix);

      g_clear_object (&tr);
    } else {
      dia_object_draw (object, DIA_RENDERER (renderer));
    }
    fprintf (renderer->file, "-6\n");
  }
}


static void
dia_xfig_renderer_class_init (DiaXfigRendererClass *klass)
{
  GObjectClass *object_class = G_OBJECT_CLASS (klass);
  DiaRendererClass *renderer_class = DIA_RENDERER_CLASS (klass);

  object_class->finalize = dia_xfig_renderer_finalize;
  object_class->set_property = dia_xfig_renderer_set_property;
  object_class->get_property = dia_xfig_renderer_get_property;

  renderer_class->begin_render = begin_render;
  renderer_class->end_render = end_render;

  renderer_class->set_linewidth = set_linewidth;
  renderer_class->set_linecaps = set_linecaps;
  renderer_class->set_linejoin = set_linejoin;
  renderer_class->set_linestyle = set_linestyle;
  renderer_class->set_fillstyle = set_fillstyle;

  renderer_class->draw_line = draw_line;
  renderer_class->draw_polyline = draw_polyline;

  renderer_class->draw_polygon = draw_polygon;

  renderer_class->draw_arc = draw_arc;
  renderer_class->fill_arc = fill_arc;

  renderer_class->draw_ellipse = draw_ellipse;

  renderer_class->draw_rect = draw_rect;
  renderer_class->draw_bezier = draw_bezier;
  renderer_class->draw_beziergon = draw_beziergon;

  renderer_class->draw_string = draw_string;

  renderer_class->draw_image = draw_image;

  renderer_class->draw_line_with_arrows = draw_line_with_arrows;
  renderer_class->draw_polyline_with_arrows = draw_polyline_with_arrows;
  renderer_class->draw_arc_with_arrows = draw_arc_with_arrows;
  renderer_class->draw_bezier_with_arrows = draw_bezier_with_arrows;
  renderer_class->draw_object = draw_object;

  g_object_class_override_property (object_class, PROP_FONT, "font");
  g_object_class_override_property (object_class, PROP_FONT_HEIGHT, "font-height");
}


static void
dia_xfig_renderer_init (DiaXfigRenderer *self)
{
}


static gboolean
export_fig (DiagramData *data,
            DiaContext  *ctx,
            const char  *filename,
            const char  *diafilename,
            void        *user_data)
{
  FILE *file;
  DiaXfigRenderer *renderer;
  char d_buf[DTOSTR_BUF_SIZE];

  file = g_fopen (filename, "w");

  if (file == NULL) {
    dia_context_add_message_with_errno (ctx,
                                        errno,
                                        _("Can't open output file %s"),
                                        dia_context_get_filename (ctx));
    return FALSE;
  }

  renderer = g_object_new (DIA_XFIG_TYPE_RENDERER, NULL);

  renderer->file = file;

  fprintf (file, "#FIG 3.2\n");
  fprintf (file, (data->paper.is_portrait ? "Portrait\n" : "Landscape\n"));
  fprintf (file, "Center\n");
  fprintf (file, "Metric\n");
  fprintf (file, "%s\n", data->paper.name);
  fprintf (file, "%s\n", xfig_dtostr (d_buf, data->paper.scaling * 100.0));
  fprintf (file, "Single\n"); /* Could we do layers this way? */
  fprintf (file, "-2\n");
  fprintf (file, "1200 2\n");

  renderer->color_pass = TRUE;

  dia_renderer_begin_render (DIA_RENDERER (renderer), NULL);

  DIA_FOR_LAYER_IN_DIAGRAM (data, layer, i, {
    if (dia_layer_is_visible (layer)) {
      dia_layer_render (layer, DIA_RENDERER (renderer), NULL, NULL, data, 0);
      renderer->depth++;
    }
  });

  dia_renderer_end_render (DIA_RENDERER (renderer));

  renderer->color_pass = FALSE;

  dia_renderer_begin_render (DIA_RENDERER (renderer), NULL);

  DIA_FOR_LAYER_IN_DIAGRAM (data, layer, i, {
    if (dia_layer_is_visible (layer)) {
      dia_layer_render (layer, DIA_RENDERER (renderer), NULL, NULL, data, 0);
      renderer->depth++;
    }
  });

  dia_renderer_end_render (DIA_RENDERER (renderer));

  g_clear_object (&renderer);

  fclose (file);

  return TRUE;
}


static const char *extensions[] = { "fig", NULL };
DiaExportFilter xfig_export_filter = {
  N_("Xfig format"),
  extensions,
  export_fig
};
