/*
 * pms.c -- save loaded image as pms
 * (C)Copyright 1998, 99 by Hiroshi Takekawa
 * This file is part of Enfle.
 *
 * Last Modified: Mon Sep 27 02:35:55 1999.
 * $Id: pms.c,v 1.3 1999/09/28 04:48:07 sian Exp $
 *
 * Enfle 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.
 *
 * Enfle 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 "enfle.h"
#include "version.h"
#include "plugin.h"
#include "pms.h"
#include "utils.h"

int
#ifdef PIC
get_plugininfo(PluginInfo *p)
#else
saver_pms_get_plugininfo(PluginInfo *p)
#endif
{
  p->version = 1;
  p->type = _Saver;
  p->pluginname = "PMS Format Saver Plugin version 0.1.1";
  p->pluginshortname = FORMAT_NAME;
  p->author = "Hiroshi Takekawa";
  p->dlhandle = NULL; /* set by plugin_load */
  p->functions.saver.save_image = pms_save_image;

  return 1;
}

static int
pms_save_image_256(Info *info, Image *p, FILE *fp)
{
  int i = p->width * p->height, count;
  unsigned char *s = p->image, c;

  /* compression not yet completed(implemented run-length only) */
  c = *s++;
  count = 1;
  for (i--; i > 0; i--) {
    if (c != *s || count == 259 || i == 0) {
      if (count >= 4) {
	fputc(0xfd, fp);
	fputc(count - 4, fp);
	fputc(c, fp);
      } else {
	for (; count > 0; count--)
	  if (c < 0xf8)
	    fputc(c, fp);
	  else {
	    fputc(0xf8, fp);
	    fputc(c, fp);
	  }
      }
      if (i > 0) {
	c = *s++;
	count = 1;
      }
    } else {
      count++;
      s++;
    }
  }

  return 1;
}

static int
pms_save_image_64k(Info *info, Image *p, FILE *fp)
{
  int i = p->width * p->height;
  unsigned char *s = p->image;

  /* compression not yet implemented */
  for (; i > 0; i--)
    if (*s < 0xf8) {
      fputc((int)*s++, fp);
      fputc((int)*s++, fp);
    } else {
      fputc(0xf8, fp);
      fputc((int)*s++, fp);
      fputc((int)*s++, fp);
    }

  return 1;
}

int
pms_save_image(Info *info, Image *p, char *outfile)
{
  FILE *fp = NULL;
  unsigned char *comment = "Created by enfle " VERSION " / " COPYRIGHT;
  unsigned char pmsh[48];
  int f, if_pal;
  int comment_len = strlen(comment);

  memset(pmsh, 0, 48);
  pmsh[0] = 'P';
  pmsh[1] = 'M';
  pmsh[2] = 1; /* version */
  put_little_word(pmsh + 4, 0x30 + comment_len + 1); /* headersize */
  put_little_dword(pmsh + 16, p->left);
  put_little_dword(pmsh + 20, p->top);
  put_little_dword(pmsh + 24, p->width);
  put_little_dword(pmsh + 28, p->height);
  switch (p->type) {
  case _INDEX:
    pmsh[6] = 8;
    put_little_dword(pmsh + 32, 0x30 + comment_len + 1 + 256 * 3);
    put_little_dword(pmsh + 36, 0x30 + comment_len + 1);
    put_little_dword(pmsh + 40, 0x30);
    if_pal = 1;
    break;
  case _RGB24:
    image_reduce(p, _RGB16);
  case _RGB16:
    pmsh[6] = 16;
    put_little_dword(pmsh + 32, 0x30 + comment_len + 1);
    put_little_dword(pmsh + 36, 0); /* alpha is not yet implemented */
    put_little_dword(pmsh + 40, 0x30);
    if_pal = 0;
    break;
  default:
    fprintf(stderr, "Unsupported image type: %d\n", p->type);
    return 0;
  }

  if ((fp = fopen(outfile, "wb")) == NULL)
    return 0;

  /* write the header */
  if (fwrite(pmsh, 1, 48, fp) != 48) {
    perror("pms_save_image() in writing header: ");
    fclose(fp);
    return 0;
  }

  /* write the comment */
  if (fwrite(comment, 1, comment_len + 1, fp) != comment_len + 1) {
    perror("pms_save_image() in writing comment");
    fclose(fp);
    return 0;
  }

  /* write the palette */
  if (if_pal)
    if (fwrite(p->colormap, 1, 256 * 3, fp) != 256 * 3) {
      perror("pms_save_image() in writing palette");
      fclose(fp);
      return 0;
    }

  /* compress and write pixels */
  f = if_pal ? pms_save_image_256(info, p, fp) : pms_save_image_64k(info, p, fp);

  fclose(fp);
  return f;
}