/*
 * Copyright (c) 1988-1997 Sam Leffler
 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Sam Leffler and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Sam Leffler and Silicon Graphics.
 *
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 *
 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

#include "libport.h"
#include "tif_config.h"

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

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "tiffio.h"
#include "tiffiop.h"

#ifndef EXIT_SUCCESS
#define EXIT_SUCCESS 0
#endif
#ifndef EXIT_FAILURE
#define EXIT_FAILURE 1
#endif

/* x% weighting -> fraction of full color */
#define PCT(x) (((x)*256 + 50) / 100)
int RED = PCT(30);   /* 30% */
int GREEN = PCT(59); /* 59% */
int BLUE = PCT(11);  /* 11% */

static void usage(int code);
static int processCompressOptions(char *);

static void compresscontig(unsigned char *out, unsigned char *rgb, uint32_t n)
{
    register int v, red = RED, green = GREEN, blue = BLUE;

    while (n-- > 0)
    {
        v = red * (*rgb++);
        v += green * (*rgb++);
        v += blue * (*rgb++);
        *out++ = v >> 8;
    }
}

static void compresssep(unsigned char *out, unsigned char *r, unsigned char *g,
                        unsigned char *b, uint32_t n)
{
    register uint32_t red = RED, green = GREEN, blue = BLUE;

    while (n-- > 0)
        *out++ =
            (unsigned char)((red * (*r++) + green * (*g++) + blue * (*b++)) >>
                            8);
}

static int checkcmap(TIFF *tif, int n, uint16_t *r, uint16_t *g, uint16_t *b)
{
    while (n-- > 0)
        if (*r++ >= 256 || *g++ >= 256 || *b++ >= 256)
            return (16);
    TIFFWarning(TIFFFileName(tif), "Assuming 8-bit colormap");
    return (8);
}

static void compresspalette(unsigned char *out, unsigned char *data, uint32_t n,
                            uint16_t *rmap, uint16_t *gmap, uint16_t *bmap)
{
    register int v, red = RED, green = GREEN, blue = BLUE;

    while (n-- > 0)
    {
        unsigned int ix = *data++;
        v = red * rmap[ix];
        v += green * gmap[ix];
        v += blue * bmap[ix];
        *out++ = v >> 8;
    }
}

static uint16_t compression = (uint16_t)-1;
static uint16_t predictor = 0;
static int jpegcolormode = JPEGCOLORMODE_RGB;
static int quality = 75; /* JPEG quality */

static void cpTags(TIFF *in, TIFF *out);

int main(int argc, char *argv[])
{
    uint32_t rowsperstrip = (uint32_t)-1;
    TIFF *in, *out;
    uint32_t w, h;
    uint16_t samplesperpixel;
    uint16_t bitspersample;
    uint16_t config;
    uint16_t photometric;
    uint16_t *red;
    uint16_t *green;
    uint16_t *blue;
    tsize_t rowsize;
    register uint32_t row;
    register tsample_t s;
    unsigned char *inbuf, *outbuf;
    char thing[1024];
    int c;
#if !HAVE_DECL_OPTARG
    extern int optind;
    extern char *optarg;
#endif

    in = (TIFF *)NULL;
    out = (TIFF *)NULL;
    inbuf = (unsigned char *)NULL;
    outbuf = (unsigned char *)NULL;

    while ((c = getopt(argc, argv, "c:r:R:G:B:h")) != -1)
        switch (c)
        {
            case 'c': /* compression scheme */
                if (!processCompressOptions(optarg))
                    usage(EXIT_FAILURE);
                break;
            case 'r': /* rows/strip */
                rowsperstrip = atoi(optarg);
                break;
            case 'R':
                RED = PCT(atoi(optarg));
                break;
            case 'G':
                GREEN = PCT(atoi(optarg));
                break;
            case 'B':
                BLUE = PCT(atoi(optarg));
                break;
            case 'h':
                usage(EXIT_SUCCESS);
                /*NOTREACHED*/
                break;
            case '?':
                usage(EXIT_FAILURE);
                /*NOTREACHED*/
                break;
        }
    if (argc - optind < 2)
        usage(EXIT_FAILURE);
    in = TIFFOpen(argv[optind], "r");
    if (in == NULL)
        return (EXIT_FAILURE);
    photometric = 0;
    TIFFGetField(in, TIFFTAG_PHOTOMETRIC, &photometric);
    if (photometric != PHOTOMETRIC_RGB && photometric != PHOTOMETRIC_PALETTE)
    {
        fprintf(
            stderr,
            "%s: Bad photometric; can only handle RGB and Palette images.\n",
            argv[optind]);
        goto tiff2bw_error;
    }
    TIFFGetField(in, TIFFTAG_SAMPLESPERPIXEL, &samplesperpixel);
    if (samplesperpixel != 1 && samplesperpixel != 3)
    {
        fprintf(stderr, "%s: Bad samples/pixel %u.\n", argv[optind],
                samplesperpixel);
        goto tiff2bw_error;
    }
    if (photometric == PHOTOMETRIC_RGB && samplesperpixel != 3)
    {
        fprintf(stderr, "%s: Bad samples/pixel %u for PHOTOMETRIC_RGB.\n",
                argv[optind], samplesperpixel);
        goto tiff2bw_error;
    }
    TIFFGetField(in, TIFFTAG_BITSPERSAMPLE, &bitspersample);
    if (bitspersample != 8)
    {
        fprintf(stderr, " %s: Sorry, only handle 8-bit samples.\n",
                argv[optind]);
        goto tiff2bw_error;
    }
    TIFFGetField(in, TIFFTAG_IMAGEWIDTH, &w);
    TIFFGetField(in, TIFFTAG_IMAGELENGTH, &h);
    TIFFGetField(in, TIFFTAG_PLANARCONFIG, &config);

    out = TIFFOpen(argv[optind + 1], "w");
    if (out == NULL)
    {
        goto tiff2bw_error;
    }
    TIFFSetField(out, TIFFTAG_IMAGEWIDTH, w);
    TIFFSetField(out, TIFFTAG_IMAGELENGTH, h);
    TIFFSetField(out, TIFFTAG_BITSPERSAMPLE, 8);
    TIFFSetField(out, TIFFTAG_SAMPLESPERPIXEL, 1);
    TIFFSetField(out, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
    cpTags(in, out);
    if (compression != (uint16_t)-1)
    {
        TIFFSetField(out, TIFFTAG_COMPRESSION, compression);
        switch (compression)
        {
            case COMPRESSION_JPEG:
                TIFFSetField(out, TIFFTAG_JPEGQUALITY, quality);
                TIFFSetField(out, TIFFTAG_JPEGCOLORMODE, jpegcolormode);
                break;
            case COMPRESSION_LZW:
            case COMPRESSION_ADOBE_DEFLATE:
            case COMPRESSION_DEFLATE:
                if (predictor != 0)
                    TIFFSetField(out, TIFFTAG_PREDICTOR, predictor);
                break;
        }
    }
    TIFFSetField(out, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_MINISBLACK);
    snprintf(thing, sizeof(thing), "B&W version of %s", argv[optind]);
    TIFFSetField(out, TIFFTAG_IMAGEDESCRIPTION, thing);
    TIFFSetField(out, TIFFTAG_SOFTWARE, "tiff2bw");
    outbuf = (unsigned char *)_TIFFmalloc(TIFFScanlineSize(out));
    if (!outbuf)
    {
        fprintf(stderr, "Out of memory\n");
        goto tiff2bw_error;
    }
    TIFFSetField(out, TIFFTAG_ROWSPERSTRIP,
                 TIFFDefaultStripSize(out, rowsperstrip));

#define pack(a, b) ((a) << 8 | (b))
    switch (pack(photometric, config))
    {
        case pack(PHOTOMETRIC_PALETTE, PLANARCONFIG_CONTIG):
        case pack(PHOTOMETRIC_PALETTE, PLANARCONFIG_SEPARATE):
            TIFFGetField(in, TIFFTAG_COLORMAP, &red, &green, &blue);
            /*
             * Convert 16-bit colormap to 8-bit (unless it looks
             * like an old-style 8-bit colormap).
             */
            if (checkcmap(in, 1 << bitspersample, red, green, blue) == 16)
            {
                int i;
#define CVT(x) (((x)*255L) / ((1L << 16) - 1))
                for (i = (1 << bitspersample) - 1; i >= 0; i--)
                {
                    red[i] = CVT(red[i]);
                    green[i] = CVT(green[i]);
                    blue[i] = CVT(blue[i]);
                }
#undef CVT
            }
            inbuf = (unsigned char *)_TIFFmalloc(TIFFScanlineSize(in));
            if (!inbuf)
            {
                fprintf(stderr, "Out of memory\n");
                goto tiff2bw_error;
            }
            for (row = 0; row < h; row++)
            {
                if (TIFFReadScanline(in, inbuf, row, 0) < 0)
                    break;
                compresspalette(outbuf, inbuf, w, red, green, blue);
                if (TIFFWriteScanline(out, outbuf, row, 0) < 0)
                    break;
            }
            break;
        case pack(PHOTOMETRIC_RGB, PLANARCONFIG_CONTIG):
            inbuf = (unsigned char *)_TIFFmalloc(TIFFScanlineSize(in));
            if (!inbuf)
            {
                fprintf(stderr, "Out of memory\n");
                goto tiff2bw_error;
            }
            for (row = 0; row < h; row++)
            {
                if (TIFFReadScanline(in, inbuf, row, 0) < 0)
                    break;
                compresscontig(outbuf, inbuf, w);
                if (TIFFWriteScanline(out, outbuf, row, 0) < 0)
                    break;
            }
            break;
        case pack(PHOTOMETRIC_RGB, PLANARCONFIG_SEPARATE):
        {
            tmsize_t inbufsize;
            rowsize = TIFFScanlineSize(in);
            inbufsize = TIFFSafeMultiply(tmsize_t, 3, rowsize);
            inbuf = (unsigned char *)_TIFFmalloc(inbufsize);
            if (!inbuf)
            {
                fprintf(stderr, "Out of memory\n");
                goto tiff2bw_error;
            }
            for (row = 0; row < h; row++)
            {
                for (s = 0; s < 3; s++)
                    if (TIFFReadScanline(in, inbuf + s * rowsize, row, s) < 0)
                        goto tiff2bw_error;
                compresssep(outbuf, inbuf, inbuf + rowsize, inbuf + 2 * rowsize,
                            w);
                if (TIFFWriteScanline(out, outbuf, row, 0) < 0)
                    break;
            }
            break;
        }
    }
#undef pack
    if (inbuf)
        _TIFFfree(inbuf);
    if (outbuf)
        _TIFFfree(outbuf);
    TIFFClose(in);
    TIFFClose(out);
    return (EXIT_SUCCESS);

tiff2bw_error:
    if (inbuf)
        _TIFFfree(inbuf);
    if (outbuf)
        _TIFFfree(outbuf);
    if (out)
        TIFFClose(out);
    if (in)
        TIFFClose(in);
    return (EXIT_FAILURE);
}

static int processCompressOptions(char *opt)
{
    if (streq(opt, "none"))
        compression = COMPRESSION_NONE;
    else if (streq(opt, "packbits"))
        compression = COMPRESSION_PACKBITS;
    else if (strneq(opt, "jpeg", 4))
    {
        char *cp = strchr(opt, ':');

        compression = COMPRESSION_JPEG;
        while (cp)
        {
            if (isdigit((int)cp[1]))
                quality = atoi(cp + 1);
            else if (cp[1] == 'r')
                jpegcolormode = JPEGCOLORMODE_RAW;
            else
                usage(EXIT_FAILURE);

            cp = strchr(cp + 1, ':');
        }
    }
    else if (strneq(opt, "lzw", 3))
    {
        char *cp = strchr(opt, ':');
        if (cp)
            predictor = atoi(cp + 1);
        compression = COMPRESSION_LZW;
    }
    else if (strneq(opt, "zip", 3))
    {
        char *cp = strchr(opt, ':');
        if (cp)
            predictor = atoi(cp + 1);
        compression = COMPRESSION_ADOBE_DEFLATE;
    }
    else
        return (0);
    return (1);
}

#define CopyField(tag, v)                                                      \
    if (TIFFGetField(in, tag, &v))                                             \
    TIFFSetField(out, tag, v)
#define CopyField2(tag, v1, v2)                                                \
    if (TIFFGetField(in, tag, &v1, &v2))                                       \
    TIFFSetField(out, tag, v1, v2)
#define CopyField3(tag, v1, v2, v3)                                            \
    if (TIFFGetField(in, tag, &v1, &v2, &v3))                                  \
    TIFFSetField(out, tag, v1, v2, v3)
#define CopyField4(tag, v1, v2, v3, v4)                                        \
    if (TIFFGetField(in, tag, &v1, &v2, &v3, &v4))                             \
    TIFFSetField(out, tag, v1, v2, v3, v4)

static void cpTag(TIFF *in, TIFF *out, uint16_t tag, uint16_t count,
                  TIFFDataType type)
{
    switch (type)
    {
        case TIFF_SHORT:
            if (count == 1)
            {
                uint16_t shortv;
                CopyField(tag, shortv);
            }
            else if (count == 2)
            {
                uint16_t shortv1, shortv2;
                CopyField2(tag, shortv1, shortv2);
            }
            else if (count == 4)
            {
                uint16_t *tr, *tg, *tb, *ta;
                CopyField4(tag, tr, tg, tb, ta);
            }
            else if (count == (uint16_t)-1)
            {
                uint16_t shortv1;
                uint16_t *shortav;
                CopyField2(tag, shortv1, shortav);
            }
            break;
        case TIFF_LONG:
        {
            uint32_t longv;
            CopyField(tag, longv);
        }
        break;
        case TIFF_RATIONAL:
            if (count == 1)
            {
                float floatv;
                CopyField(tag, floatv);
            }
            else if (count == (uint16_t)-1)
            {
                float *floatav;
                CopyField(tag, floatav);
            }
            break;
        case TIFF_ASCII:
        {
            char *stringv;
            CopyField(tag, stringv);
        }
        break;
        case TIFF_DOUBLE:
            if (count == 1)
            {
                double doublev;
                CopyField(tag, doublev);
            }
            else if (count == (uint16_t)-1)
            {
                double *doubleav;
                CopyField(tag, doubleav);
            }
            break;
        default:
            TIFFError(TIFFFileName(in),
                      "Data type %d is not supported, tag %d skipped.", tag,
                      type);
    }
}

#undef CopyField4
#undef CopyField3
#undef CopyField2
#undef CopyField

static const struct cpTag
{
    uint16_t tag;
    uint16_t count;
    TIFFDataType type;
} tags[] = {
    {TIFFTAG_SUBFILETYPE, 1, TIFF_LONG},
    {TIFFTAG_THRESHHOLDING, 1, TIFF_SHORT},
    {TIFFTAG_DOCUMENTNAME, 1, TIFF_ASCII},
    {TIFFTAG_IMAGEDESCRIPTION, 1, TIFF_ASCII},
    {TIFFTAG_MAKE, 1, TIFF_ASCII},
    {TIFFTAG_MODEL, 1, TIFF_ASCII},
    {TIFFTAG_MINSAMPLEVALUE, 1, TIFF_SHORT},
    {TIFFTAG_MAXSAMPLEVALUE, 1, TIFF_SHORT},
    {TIFFTAG_XRESOLUTION, 1, TIFF_RATIONAL},
    {TIFFTAG_YRESOLUTION, 1, TIFF_RATIONAL},
    {TIFFTAG_PAGENAME, 1, TIFF_ASCII},
    {TIFFTAG_XPOSITION, 1, TIFF_RATIONAL},
    {TIFFTAG_YPOSITION, 1, TIFF_RATIONAL},
    {TIFFTAG_RESOLUTIONUNIT, 1, TIFF_SHORT},
    {TIFFTAG_SOFTWARE, 1, TIFF_ASCII},
    {TIFFTAG_DATETIME, 1, TIFF_ASCII},
    {TIFFTAG_ARTIST, 1, TIFF_ASCII},
    {TIFFTAG_HOSTCOMPUTER, 1, TIFF_ASCII},
    {TIFFTAG_WHITEPOINT, 2, TIFF_RATIONAL},
    {TIFFTAG_PRIMARYCHROMATICITIES, (uint16_t)-1, TIFF_RATIONAL},
    {TIFFTAG_HALFTONEHINTS, 2, TIFF_SHORT},
    {TIFFTAG_INKSET, 1, TIFF_SHORT},
    {TIFFTAG_DOTRANGE, 2, TIFF_SHORT},
    {TIFFTAG_TARGETPRINTER, 1, TIFF_ASCII},
    {TIFFTAG_SAMPLEFORMAT, 1, TIFF_SHORT},
    {TIFFTAG_YCBCRCOEFFICIENTS, (uint16_t)-1, TIFF_RATIONAL},
    {TIFFTAG_YCBCRSUBSAMPLING, 2, TIFF_SHORT},
    {TIFFTAG_YCBCRPOSITIONING, 1, TIFF_SHORT},
    {TIFFTAG_REFERENCEBLACKWHITE, (uint16_t)-1, TIFF_RATIONAL},
    {TIFFTAG_EXTRASAMPLES, (uint16_t)-1, TIFF_SHORT},
    {TIFFTAG_SMINSAMPLEVALUE, 1, TIFF_DOUBLE},
    {TIFFTAG_SMAXSAMPLEVALUE, 1, TIFF_DOUBLE},
    {TIFFTAG_STONITS, 1, TIFF_DOUBLE},
};
#define NTAGS (sizeof(tags) / sizeof(tags[0]))

static void cpTags(TIFF *in, TIFF *out)
{
    const struct cpTag *p;
    for (p = tags; p < &tags[NTAGS]; p++)
    {
        if (p->tag == TIFFTAG_GROUP3OPTIONS)
        {
            uint16_t compression;
            if (!TIFFGetField(in, TIFFTAG_COMPRESSION, &compression) ||
                compression != COMPRESSION_CCITTFAX3)
                continue;
        }
        if (p->tag == TIFFTAG_GROUP4OPTIONS)
        {
            uint16_t compression;
            if (!TIFFGetField(in, TIFFTAG_COMPRESSION, &compression) ||
                compression != COMPRESSION_CCITTFAX4)
                continue;
        }
        cpTag(in, out, p->tag, p->count, p->type);
    }
}
#undef NTAGS

static const char usage_info[] =
    "Convert a color TIFF image to greyscale\n\n"
    "usage: tiff2bw [options] input.tif output.tif\n"
    "where options are:\n"
    " -R %		use #% from red channel\n"
    " -G %		use #% from green channel\n"
    " -B %		use #% from blue channel\n"
    "\n"
    " -r #		make each strip have no more than # rows\n"
    "\n"
#ifdef LZW_SUPPORT
    " -c lzw[:opts]	compress output with Lempel-Ziv & Welch encoding\n"
    /* "    LZW options:\n" */
    "    #  set predictor value\n"
    "    For example, -c lzw:2 for LZW-encoded data with horizontal "
    "differencing\n"
#endif
#ifdef ZIP_SUPPORT
    " -c zip[:opts]	compress output with deflate encoding\n"
    /* "    Deflate (ZIP) options:\n" */
    "    #  set predictor value\n"
#endif
#ifdef PACKBITS_SUPPORT
    " -c packbits	compress output with packbits encoding\n"
#endif
#ifdef CCITT_SUPPORT
    " -c g3[:opts]	compress output with CCITT Group 3 encoding\n"
    " -c g4		compress output with CCITT Group 4 encoding\n"
#endif
#if defined(LZW_SUPPORT) || defined(ZIP_SUPPORT) ||                            \
    defined(PACKBITS_SUPPORT) || defined(CCITT_SUPPORT)
    " -c none	use no compression algorithm on output\n"
#endif
    "\n";

static void usage(int code)
{
    FILE *out = (code == EXIT_SUCCESS) ? stdout : stderr;

    fprintf(out, "%s\n\n", TIFFGetVersion());
    fprintf(out, "%s", usage_info);
    exit(code);
}