#include <stdio.h>
#include <math.h>
#include <string.h>
#include <stdlib.h>
#include "gd.h"

#define TRUE 1
#define FALSE 0

/* Exported functions: */
extern void gdImageGd(gdImagePtr im, FILE *out);


/* Use this for commenting out debug-print statements. */
/* Just use the first '#define' to allow all the prints... */
/*#define GD2_DBG(s) (s) */
#define GD2_DBG(s)

/* */
/* Shared code to read color tables from gd file. */
/* */
int _gdGetColors(gdIOCtx *in, gdImagePtr im)
{
        int i;

        if (!gdGetByte(&im->colorsTotal, in)) {
                goto fail1;
        }
        if (!gdGetWord(&im->transparent, in)) {
                goto fail1;
        }
        if (im->transparent == 257) {
                im->transparent = (-1);
        }

        GD2_DBG(printf("Pallette had %d colours (T=%d)\n",im->colorsTotal, im->transparent));

        for (i=0; (i<gdMaxColors); i++) {
                if (!gdGetByte(&im->red[i], in)) {
                        goto fail1;
                }
                if (!gdGetByte(&im->green[i], in)) {
                        goto fail1;
                }
                if (!gdGetByte(&im->blue[i], in)) {
                        goto fail1;
                }
        }

        for (i=0; (i < im->colorsTotal); i++) {
           im->open[i] = 0;
        };

        return TRUE;
fail1:
        return FALSE;
}

/* */
/* Use the common basic header info to make the image object. */
/* This is also called from _gd2CreateFromFile */
/* */
static
gdImagePtr _gdCreateFromFile(gdIOCtx *in, int *sx, int *sy)
{
        gdImagePtr im;

        if (!gdGetWord(sx, in)) {
                goto fail1;
        }
        if (!gdGetWord(sy, in)) {
                goto fail1;
        }

        GD2_DBG(printf("Image is %dx%d\n", *sx, *sy));

        im = gdImageCreate(*sx, *sy);

        if (!_gdGetColors(in, im)) {
                goto fail2;
        }

        return im;
fail2:
        gdImageDestroy(im);
fail1:
        return 0;
}

gdImagePtr gdImageCreateFromGd(FILE *inFile)
{
        gdImagePtr	im;
        gdIOCtx		*in;

        in = gdNewFileCtx(inFile);
	im = gdImageCreateFromGdCtx(in);

	in->free(in);

	return im;
}

gdImagePtr gdImageCreateFromGdCtx(gdIOCtxPtr in)
{
	int sx, sy;
	int x, y;
        gdImagePtr im;

	/* Read the header */
	im = _gdCreateFromFile(in, &sx, &sy);

	if (im == NULL) {
		goto fail1;
	};

	/* Then the data... */
	for (y=0; (y<sy); y++) {
		for (x=0; (x<sx); x++) {	
			int ch;
			ch = gdGetC(in);
			if (ch == EOF) {
				goto fail2;
			}
			/* ROW-MAJOR IN GD 1.3 */
			im->pixels[y][x] = ch;
		}
	}

	return im;

fail2:
        gdImageDestroy(im);
fail1:
        return 0;
}

void _gdPutColors(gdImagePtr im, gdIOCtx *out)
{
        int i;
        int trans;

        gdPutC((unsigned char)im->colorsTotal, out);
        trans = im->transparent;
        if (trans == (-1)) {
                trans = 257;
        }
        gdPutWord(trans, out);
        for (i=0; (i<gdMaxColors); i++) {
                gdPutC((unsigned char)im->red[i], out);
                gdPutC((unsigned char)im->green[i], out);
                gdPutC((unsigned char)im->blue[i], out);
        }
}

static
void _gdPutHeader(gdImagePtr im, gdIOCtx *out)
{
        gdPutWord(im->sx, out);
        gdPutWord(im->sy, out);

	_gdPutColors(im, out);

}

static void _gdImageGd(gdImagePtr im, gdIOCtx *out)
{
	int x, y;

	_gdPutHeader(im, out);

	for (y=0; (y < im->sy); y++) {	
		for (x=0; (x < im->sx); x++) {	
			/* ROW-MAJOR IN GD 1.3 */
			gdPutC((unsigned char)im->pixels[y][x], out);
		}
	}
}

void gdImageGd(gdImagePtr im, FILE *outFile)
{
        gdIOCtx   *out = gdNewFileCtx(outFile);
        _gdImageGd(im, out);
	out->free(out);
}

void* gdImageGdPtr(gdImagePtr im, int *size)
{
	void	*rv;
        gdIOCtx   *out = gdNewDynamicCtx(2048, NULL);
        _gdImageGd(im, out);
        rv = gdDPExtractData(out,size);
	out->free(out);
	return rv;
}