/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF.  The full HDF copyright notice, including       *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://support.hdfgroup.org/ftp/HDF/releases/.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include <stdio.h>
#include <stdlib.h>

#include "gif.h"

extern int hdfWriteGIF(FILE *fp, BYTE *pic, int ptype, int w, int h, BYTE *rmap, BYTE *gmap, BYTE *bmap,
                       BYTE *pc2ncmap, int numcols, int colorstyle, int BitsPerPixel);

int EndianOrder;

static void
putword(int w, FILE *fp)
{
    /* writes a 16-bit integer in GIF order (LSB first) */

    fputc(w & 0xff, fp);

    fputc((w >> 8) & 0xff, fp);
}

int
main(int argc, char **argv)
{
    intn  status;                  /* status for functions returning an intn */
    int32 file_id;                 /* HDF file identifier */
    int32 gr_id;                   /* GR interface identifier */
    int32 ri_id, pal_id, start[2]; /* start position to write for each dimension */
    int32 stride[2], dim_sizes[2]; /* dimension sizes of the image array */
    int32 interlace_mode;          /* interlace mode of the image */
    int32 data_type;               /* data type of the image data */
    int32 i, index;

    char gr_name[256];

    FILE *fpGif;

    int32 ncomp;
    int32 num_attrs;
    int32 num_entries;
    int32 n_images;
    int32 n_fileattributes;

    BYTE *Image;
    /* compression structs */

    char *HDFName;
    char *GIFName;
    /* reference variables */

    int has_local_palette; /* treated as a flag */
    int loop_times;        /* number of times to loop, i'm going to treat it as a yes or no */

    BYTE *b;
    BYTE  x;

    BYTE GlobalPalette[256][3];
    BYTE Red[256];
    BYTE Green[256];
    BYTE Blue[256];

    int RWidth, RHeight;
    int ColorMapSize, InitCodeSize, Background, BitsPerPixel;
    int j, nc;
    int numcols = 256;
    int time_out;

    BYTE pc2nc[256], r1[256], g1[256], b1[256];
    if (argc < 3) {
        printf("Wrong number of arguments.\nUsage:\nhdf2gif <hdf file> <gif file>\n");
        exit(-1);
    }

    HDFName = argv[1];
    GIFName = argv[2];
    /* Set a default 10 ms time between two consecutive images in case of multiple image file */
    if (argc > 3)
        time_out = atoi(argv[3]);
    else
        time_out = 10;

    /* Do Endian Order testing and set Endian Order */
    x           = 0x0001;
    b           = (BYTE *)&x;
    EndianOrder = (b[0] ? 1 : 0);

    start[0] = start[1] = 0;
    stride[0] = stride[1] = 1;

    /*Start HDF file*/
    file_id = Hopen(HDFName, DFACC_READ, 0);
    if (file_id == -1) {
        printf("Unable to open HDF file");
        status = HEvalue(1);
        printf("%s\n", HEstring(status));
        exit(0);
    }

    if (!(fpGif = fopen(GIFName, "wb"))) {
        printf("Error opening gif file for output. Aborting.\n");
        exit(-1);
    }

    /* Open the hdf file using the GR interface and retrieve the images from it
    ** Note that for now the images have to be 8 bit. If they are 24 bit this
    ** program cannot handle it. I shall try to include it, if not please
    ** refer to the file hdf2gif.c in the source code for the remormat utility.
    ** There you should find the code to convert 24 bit images to 8 bit (GIF)
    */
    gr_id = GRstart(file_id);

    if ((status = GRfileinfo(gr_id, &n_images, &n_fileattributes)) == -1) {
        status = HEvalue(1);
        printf("%s\n", HEstring(status));
        exit(0);
    }

    if (n_images < 1) {
        printf("Error: No GRimages found in hdf file. Aborting.\n");
        exit(-1);
    }

    Background = 0;
    for (index = 0; index < n_images; index++) {

        has_local_palette = true;
        ri_id             = GRselect(gr_id, index);
        if ((pal_id = GRgetlutid(ri_id, 0)) == -1)
            has_local_palette = false;

        if (has_local_palette) {
            status = GRgetlutinfo(pal_id, &ncomp, &data_type, &interlace_mode, &num_entries);
            status = GRreadlut(pal_id, (void *)&GlobalPalette);
        }

        status = GRgetiminfo(ri_id, gr_name, &ncomp, &data_type, &interlace_mode, dim_sizes, &num_attrs);
        if (!(data_type == DFNT_CHAR || data_type == DFNT_UCHAR || data_type == DFNT_INT8 ||
              data_type == DFNT_UINT8 || data_type == DFNT_NINT8 || data_type == DFNT_NUINT8)) {
            printf("The GR data type of image %s in the hdf file appears not to be 8-bit. Trying next "
                   "image...\n",
                   gr_name);
            continue;
        }

        /* BUG FIX 601 - pkamat */
        if (1 != ncomp) {     /* not an 8-bit image */
            if (3 == ncomp) { /* 24-bit image */
                printf("The GR data type of image %s in the hdf file appears to be a 24-bit image. ",
                       gr_name);
                printf("Use hdf2jpeg to convert this image. Trying next image... \n");
                continue;
            }
            printf("The GR data type of image %s in the hdf file does not appear to be a 8-bit image. ",
                   gr_name);
            printf("Trying next image... \n");
            continue;
        }
        /* End BUG FIX 601 */

        Image  = (BYTE *)malloc(dim_sizes[0] * dim_sizes[1]);
        status = GRreadimage(ri_id, start, stride, dim_sizes, Image);

        /* If the first image does not have a palette, I make my own global color table
        ** Obviously this is not the best thing to do, better steps would be:
        ** 1. Check for either a global palette or a global attribute called palette
        ** 2. Check for palettes in any of the other images.
        */
        if (!has_local_palette) {
            for (i = 0; i < 256; i++) {
                Red[i]   = 255 - i;
                Green[i] = 255 - i;
                Blue[i]  = 255 - i;
            }
        }
        else {
            for (i = 0; i < 256; i++) {
                Red[i]   = GlobalPalette[i][0];
                Green[i] = GlobalPalette[i][1];
                Blue[i]  = GlobalPalette[i][2];
            }
        }

        for (i = 0; i < 256; i++) {
            pc2nc[i] = r1[i] = g1[i] = b1[i] = 0;
        }
        /* compute number of unique colors */
        nc = 0;
        for (i = 0; i < numcols; i++) {
            /* see if color #i is already used */
            for (j = 0; j < i; j++) {
                if (Red[i] == Red[j] && Green[i] == Green[j] && Blue[i] == Blue[j])
                    break;
            }
            if (j == i) { /* wasn't found */
                pc2nc[i] = nc;
                r1[nc]   = Red[i];
                g1[nc]   = Green[i];
                b1[nc]   = Blue[i];
                nc++;
            }
            else
                pc2nc[i] = pc2nc[j];
        }
        /* figure out 'BitsPerPixel' */
        for (i = 1; i < 8; i++) {
            if ((1 << i) >= nc)
                break;
        }
        BitsPerPixel = i;
        ColorMapSize = 1 << BitsPerPixel;

        RWidth  = dim_sizes[0];
        RHeight = dim_sizes[1];

        if (BitsPerPixel <= 1)
            InitCodeSize = 2;
        else
            InitCodeSize = BitsPerPixel;

        if (!fpGif) {
            fprintf(stderr, "WriteGIF: file not open for writing\n");
            return (1);
        }

        /* If it is the first image we do all the header stuff that isn't required for the
        ** rest of the images.
        */
        if (index == 0) {
            /* Write out the GIF header and logical screen descriptor */
            if (n_images > 0) {
                fwrite("GIF89a", 1, 6, fpGif); /* the GIF magic number */
                loop_times = 0;
            }
            else {
                fwrite("GIF87a", 1, 6, fpGif); /* the GIF magic number */
                loop_times = 1;
            }

            putword(RWidth, fpGif); /* screen descriptor */
            putword(RHeight, fpGif);

            i = 0x00;                /* No, there is no color map */
            i |= (8 - 1) << 4;       /* OR in the color resolution (hardwired 8) */
            i |= (BitsPerPixel - 1); /* OR in the # of bits per pixel */
            fputc(i, fpGif);

            fputc(Background, fpGif); /* background color */

            fputc(0, fpGif); /* future expansion byte */

            /* If loop_times is 0 , put in the application extension to make the gif anime loop
            ** indefinitely
            */
            if (!loop_times) {
                fputc(0x21, fpGif);
                fputc(0xFF, fpGif);
                fputc(11, fpGif);
                fwrite("NETSCAPE2.0", 1, 11, fpGif);
                fputc(3, fpGif);
                fputc(1, fpGif);
                fputc(0, fpGif);
                fputc(0, fpGif);
                fputc(0, fpGif);
            }
        }

        if (n_images > 1) {
            /* write a graphic control block */
            fputc(0x21, fpGif);
            fputc(0xF9, fpGif);
            fputc(4, fpGif);
            fputc(4, fpGif);
            putword(time_out, fpGif);
            fputc(255, fpGif);
            fputc(0, fpGif);
        }

        /* Put Image Descriptor
        ** Hardwiring Left Offset and Top Offset to 0x00
        */

        fputc(0x2c, fpGif);
        putword(0x00, fpGif);
        putword(0x00, fpGif);
        putword(RWidth, fpGif);
        putword(RHeight, fpGif);
        if (has_local_palette) {
            fputc((0x80 | (BitsPerPixel - 1)), fpGif);
            for (i = 0; i < ColorMapSize; i++) { /* write out Global colormap */
                fputc(r1[i], fpGif);
                fputc(g1[i], fpGif);
                fputc(b1[i], fpGif);
            }
        }
        else
            fputc(0x00, fpGif);

        fputc(InitCodeSize, fpGif);

        i = hdfWriteGIF(fpGif, Image, 0, dim_sizes[0], dim_sizes[1], r1, g1, b1, pc2nc, 256, 8, BitsPerPixel);
        fputc(0x00, fpGif);
        free(Image);
        status = GRendaccess(ri_id);
    }

    fputc(';', fpGif); /* Write GIF file terminator */
    status = GRend(gr_id);

    /* Close the HDF file */
    status = Hclose(file_id);
    fclose(fpGif);
    return (0);
}