/*
Copyright (C) 2000 Willem Jan Palenstijn

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.
*/


/*
A large part of this code is from the GIMP's PCX plugin:
"This code is based in parts on code by Francisco Bustamante, but the
largest portion of the code has been rewritten and is now maintained
occasionally by Nick Lamb njl195@zepler.org.uk."

It has been partly rewritten to use an SDL surface as input.
*/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#ifndef ALPHA_LINUX_CXX
#  include <cstdlib>
#endif

#include "SDL_video.h"
#include "SDL_endian.h"
#include <iostream>

#ifndef UNDER_CE
using std::cout;
using std::endl;
using std::free;
using std::malloc;
#endif

#if SDL_BYTEORDER == SDL_LIL_ENDIAN
#define qtohl(x) (x)
#define qtohs(x) (x)
#else
#define qtohl(x) \
        ((Uint32)((((Uint32)(x) & 0x000000ffU) << 24) | \
                  (((Uint32)(x) & 0x0000ff00U) <<  8) | \
                  (((Uint32)(x) & 0x00ff0000U) >>  8) | \
                  (((Uint32)(x) & 0xff000000U) >> 24)))
#define qtohs(x) \
        ((Uint16)((((Uint16)(x) & 0x00ff) << 8) | \
                  (((Uint16)(x) & 0xff00) >> 8)))
#endif
#define htoql(x) qtohl(x)
#define htoqs(x) qtohs(x)

typedef struct PCX_Header {
  Uint8 manufacturer;
  Uint8 version;
  Uint8 compression;
  Uint8 bpp;
  Sint16 x1, y1;
  Sint16 x2, y2;
  Sint16 hdpi;
  Sint16 vdpi;
  Uint8 colormap[48];
  Uint8 reserved;
  Uint8 planes;
  Sint16 bytesperline;
  Sint16 color;
  Uint8 filler[58];
} PCX_Header;

static void writeline (SDL_RWops *dst, Uint8* buffer, int bytes) {
  Uint8 value, count, tmp;
  Uint8 *finish = buffer + bytes;

  while (buffer < finish) {
  
    value = *(buffer++);
    count = 1;
    
    while (buffer < finish && count < 63 && *buffer == value) {
      count++; buffer++;
    }
    
    if (value < 0xc0 && count == 1) {
      SDL_RWwrite(dst, &value, 1, 1);
    } else {
      tmp = count + 0xc0;
      SDL_RWwrite(dst, &tmp, 1, 1);
      SDL_RWwrite(dst, &value, 1, 1);
    }
  }
}


static void save_8 (SDL_RWops *dst, int width, int height, 
		    int pitch, Uint8* buffer)
{
  int row;

  for (row = 0; row < height; ++row) 
    {
      writeline (dst, buffer, width);
      buffer += pitch;
    }
}


static void save_24 (SDL_RWops *dst, int width, int height,
		     int pitch, Uint8* buffer)
{
  int x, y, c;
  Uint8 *line;

  line = (Uint8 *) malloc (width);

  for (y = 0; y < height; ++y) {
    for (c = 2; c >= 0; --c) {
      for (x = 0; x < width; ++x) {
	line[x] = buffer[(3*x) + c];
      }
      writeline (dst, line, width);
    }
    buffer += pitch;
  }
  free (line);
}

static bool save_image(SDL_Surface *surface, SDL_RWops *dst)
{
  Uint8 *cmap = 0;
  Uint8 *pixels;
  Uint8 tmp;
  int width, height, pitch;
  int colors = 0, i;
  PCX_Header header;

  width = surface->w;
  height = surface->h;
  pixels = (Uint8*)surface->pixels;
  pitch = surface->pitch;

  header.manufacturer = 0x0a;
  header.version = 5;
  header.compression = 1;

  if (surface->format->palette && surface->format->BitsPerPixel == 8) {
    colors = surface->format->palette->ncolors;
    cmap = (Uint8*)malloc(3*colors);
    for (i = 0; i < colors; i++) {
      cmap[3*i] = surface->format->palette->colors[i].r;
      cmap[3*i+1] = surface->format->palette->colors[i].g;
      cmap[3*i+2] = surface->format->palette->colors[i].b;
    }
    header.bpp = 8;
    header.bytesperline = htoqs (width);
    header.planes = 1;
    header.color = htoqs (1);
  } else if (surface->format->BitsPerPixel == 24) {
    header.bpp = 8;
    header.bytesperline = htoqs (width);
    header.planes = 3;
    header.color = htoqs(1);
  } else {
    return false;
  }
  
  header.x1 = 0;
  header.y1 = 0;
  header.x2 = htoqs (width - 1);
  header.y2 = htoqs (height - 1);

  header.hdpi = htoqs (300);
  header.vdpi = htoqs (300);
  header.reserved = 0;

  /* write header */
  /*  fp_offset = SDL_RWtell(dst);*/
  SDL_RWwrite(dst, &header, sizeof(PCX_Header), 1);

  if (cmap) {
    save_8 (dst, width, height, pitch, pixels);

    /* write palette */
    tmp = 0x0c;
    SDL_RWwrite(dst, &tmp, 1, 1);
    SDL_RWwrite(dst, cmap, 3, colors);

    /* fill unused colors */
    tmp = 0;
    for (i = colors; i < 256; i++) {
      SDL_RWwrite(dst, &tmp, 1, 1);
      SDL_RWwrite(dst, &tmp, 1, 1);
      SDL_RWwrite(dst, &tmp, 1, 1);
    }

    free(cmap);
  } else {
    save_24 (dst, width, height, pitch, pixels);
  }

  return true;
}

bool SavePCX_RW (SDL_Surface *saveme, SDL_RWops *dst, bool freedst)
{
  SDL_Surface *surface;
  bool found_error = false;

  cout << "Taking screenshot...";

  surface = NULL;
  if ( dst ) {
    if ( saveme->format->palette ) {
      if ( saveme->format->BitsPerPixel == 8 ) {
	surface = saveme;
      } else {
	found_error = true;
	cout << saveme->format->BitsPerPixel 
	     << "bpp PCX files not supported" << endl;
      }
    }
    else if ( (saveme->format->BitsPerPixel == 24) &&
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
	      (saveme->format->Rmask == 0x00FF0000) &&
	      (saveme->format->Gmask == 0x0000FF00) &&
	      (saveme->format->Bmask == 0x000000FF)
#else
	      (saveme->format->Rmask == 0x000000FF) &&
	      (saveme->format->Gmask == 0x0000FF00) &&
	      (saveme->format->Bmask == 0x00FF0000)
#endif
	      ) {
      surface = saveme;
    } else {
      SDL_Rect bounds;
      
      /* Convert to 24 bits per pixel */
      surface = SDL_CreateRGBSurface(SDL_SWSURFACE,
				     saveme->w, saveme->h, 24,
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
				     0x00FF0000, 0x0000FF00, 0x000000FF,
#else
				     0x000000FF, 0x0000FF00, 0x00FF0000,
#endif
				     0);

      if ( surface != NULL ) {
	bounds.x = 0;
	bounds.y = 0;
	bounds.w = saveme->w;
	bounds.h = saveme->h;
	if ( SDL_LowerBlit(saveme, &bounds, surface,
			   &bounds) < 0 ) {
	  SDL_FreeSurface(surface);
	  cout << "Couldn't convert image to 24 bpp for screenshot";
	  found_error = true;
	  surface = NULL;
	}
      }
    }
  } else {
    /* no valid target */
  }

  if ( surface && (SDL_LockSurface(surface) == 0) ) {
    
    found_error |= !save_image(surface, dst);

    /* Close it up.. */
    SDL_UnlockSurface(surface);
    if ( surface != saveme ) {
      SDL_FreeSurface(surface);
    }
  }

  
  if ( freedst && dst ) {
    SDL_RWclose(dst);
  }

  if (!found_error) {
    cout << "Done!" << endl;
    return true;
  }

  return false;
}