#include "config.h"
#include "Imlib2_Loader.h"

#include <setjmp.h>
#include <tiffio.h>

#define DBG_PFX "LDR-tiff"

static const char *const _formats[] = { "tiff", "tif" };

#define DD(fmt...)  DC(DBG_PFX, 0x80, fmt)

static void
_tiff_error(const char *module, const char *fmt, va_list ap)
{
#if IMLIB2_DEBUG
    char            buf[128];
    vsnprintf(buf, sizeof(buf), fmt, ap);
    D("%s: %s: %s\n", __func__, module, buf);
#endif
}

static struct {
    const unsigned char *data, *dptr;
    unsigned int    size;
} mdata;

static void
mm_init(const void *src, unsigned int size)
{
    mdata.data = mdata.dptr = src;
    mdata.size = size;
}

static          tmsize_t
_tiff_read(thandle_t ctx, void *buf, tmsize_t len)
{
    DD("%s: len=%ld\n", __func__, (long)len);

    if (mdata.dptr + len > mdata.data + mdata.size)
        return 0;               /* Out of data */

    memcpy(buf, mdata.dptr, len);
    mdata.dptr += len;

    return len;
}

static          tmsize_t
_tiff_write(thandle_t ctx, void *buf, tmsize_t len)
{
    DD("%s: len=%ld\n", __func__, (long)len);

    return 0;
}

static          toff_t
_tiff_seek(thandle_t ctx, toff_t offs, int whence)
{
    const unsigned char *dptr;

    DD("%s: offs=%ld, whence=%d\n", __func__, (long)offs, whence);

    switch (whence)
    {
    default:
        return -1;
    case SEEK_SET:
        dptr = mdata.data + offs;
        break;
    case SEEK_CUR:
        dptr = mdata.data += offs;
        break;
    case SEEK_END:
        dptr = mdata.data + mdata.size + offs;
        break;
    }

    if (dptr > mdata.data + mdata.size)
        return -1;              /* Out of data */

    mdata.dptr = dptr;

    return mdata.dptr - mdata.data;
}

static int
_tiff_close(thandle_t ctx)
{
    DD("%s\n", __func__);

    return 0;
}

static          toff_t
_tiff_size(thandle_t ctx)
{
    DD("%s: size=%d\n", __func__, mdata.size);

    return mdata.size;
}

static int
_tiff_map(thandle_t ctx, void **base, toff_t *size)
{
    DD("%s\n", __func__);

    *base = (void *)mdata.data;
    *size = mdata.size;

    return 1;
}
static void
_tiff_unmap(thandle_t ctx, void *base, toff_t size)
{
    DD("%s\n", __func__);
}

/* This is a wrapper data structure for TIFFRGBAImage, so that data can be */
/* passed into the callbacks. More elegent, I think, than a bunch of globals */

typedef struct {
    TIFFRGBAImage   rgba;
    tileContigRoutine put_contig;
    tileSeparateRoutine put_separate;
    ImlibImage     *image;
} TIFFRGBAImage_Extra;

#define PIM(_x, _y) buffer + ((_x) + image_width * (_y))

static void
raster(TIFFRGBAImage_Extra *img, uint32_t *rast,
       uint32_t x, uint32_t y, uint32_t w, uint32_t h)
{
    uint32_t        image_width, image_height;
    uint32_t       *pixel, pixel_value;
    uint32_t        i, j, k;
    uint32_t       *buffer_pixel, *buffer = img->image->data;
    int             alpha_premult;
    int             a, r, g, b;

    image_width = img->image->w;
    image_height = img->image->h;

#if 0
    printf("%s: x,y=%d,%d wxh=%dx%d (image %dx%d)\n", __func__,
           x, y, w, h, image_width, image_height);
#endif

    /* rast seems to point to the beginning of the last strip processed */
    /* so you need use negative offsets. Bizzare. Someone please check this */
    /* I don't understand why, but that seems to be what's going on. */
    /* libtiff needs better docs! */

    alpha_premult = img->rgba.alpha == EXTRASAMPLE_UNASSALPHA;

    switch (img->rgba.orientation)
    {
    default:
    case ORIENTATION_TOPLEFT:
    case ORIENTATION_TOPRIGHT:
        for (j = 0; j < h; j++)
        {
            pixel = rast - j * image_width;

            for (i = 0; i < w; i++)
            {
                pixel_value = *pixel++;
                a = TIFFGetA(pixel_value);
                r = TIFFGetR(pixel_value);
                g = TIFFGetG(pixel_value);
                b = TIFFGetB(pixel_value);
                if ((a > 0) && (a < 255) && (alpha_premult))
                {
                    r = (r * 255) / a;
                    g = (g * 255) / a;
                    b = (b * 255) / a;
                }
                k = x + i;
                if (img->rgba.orientation == ORIENTATION_TOPRIGHT)
                    k = image_width - 1 - k;
                buffer_pixel = PIM(k, image_height - 1 - (y - j));
                *buffer_pixel = PIXEL_ARGB(a, r, g, b);
            }
        }
        break;
    case ORIENTATION_BOTRIGHT:
    case ORIENTATION_BOTLEFT:
        for (j = 0; j < h; j++)
        {
            pixel = rast + j * image_width;

            for (i = 0; i < w; i++)
            {
                pixel_value = *pixel++;
                a = TIFFGetA(pixel_value);
                r = TIFFGetR(pixel_value);
                g = TIFFGetG(pixel_value);
                b = TIFFGetB(pixel_value);
                if ((a > 0) && (a < 255) && (alpha_premult))
                {
                    r = (r * 255) / a;
                    g = (g * 255) / a;
                    b = (b * 255) / a;
                }
                k = x + i;
                if (img->rgba.orientation == ORIENTATION_BOTRIGHT)
                    k = image_width - 1 - k;
                buffer_pixel = PIM(k, image_height - 1 - (y + j));
                *buffer_pixel = PIXEL_ARGB(a, r, g, b);
            }
        }
        break;

    case ORIENTATION_LEFTTOP:
    case ORIENTATION_RIGHTTOP:
        for (i = 0; i < h; i++)
        {
            pixel = rast - i * image_height;

            for (j = 0; j < w; j++)
            {
                pixel_value = *pixel++;
                a = TIFFGetA(pixel_value);
                r = TIFFGetR(pixel_value);
                g = TIFFGetG(pixel_value);
                b = TIFFGetB(pixel_value);
                if ((a > 0) && (a < 255) && (alpha_premult))
                {
                    r = (r * 255) / a;
                    g = (g * 255) / a;
                    b = (b * 255) / a;
                }
                k = y - i;
                if (img->rgba.orientation == ORIENTATION_LEFTTOP)
                    k = image_width - 1 - k;
                buffer_pixel = PIM(k, x + j);
                *buffer_pixel = PIXEL_ARGB(a, r, g, b);
            }
        }
        break;
    case ORIENTATION_RIGHTBOT:
    case ORIENTATION_LEFTBOT:
        for (i = 0; i < h; i++)
        {
            pixel = rast + i * image_height;

            for (j = 0; j < w; j++)
            {
                pixel_value = *pixel++;
                a = TIFFGetA(pixel_value);
                r = TIFFGetR(pixel_value);
                g = TIFFGetG(pixel_value);
                b = TIFFGetB(pixel_value);
                if ((a > 0) && (a < 255) && (alpha_premult))
                {
                    r = (r * 255) / a;
                    g = (g * 255) / a;
                    b = (b * 255) / a;
                }
                k = y + i;
                if (img->rgba.orientation == ORIENTATION_RIGHTBOT)
                    k = image_width - 1 - k;
                buffer_pixel = PIM(k, image_height - 1 - (x + j));
                *buffer_pixel = PIXEL_ARGB(a, r, g, b);
            }
        }
        break;
    }

    if (img->image->lc)
    {
        /* for tile based images, we just progress each tile because */
        /* of laziness. Couldn't think of a good way to do this */

        switch (img->rgba.orientation)
        {
        default:
        case ORIENTATION_TOPLEFT:
            if (w >= image_width)
            {
                __imlib_LoadProgressRows(img->image, image_height - y - 1, h);
            }
            else
            {
                /* for tile based images, we just progress each tile because */
                /* of laziness. Couldn't think of a good way to do this */
                y = image_height - 1 - y;
                goto progress_a;
            }
            break;
        case ORIENTATION_TOPRIGHT:
            y = image_height - 1 - y;
            goto progress_a;
        case ORIENTATION_BOTRIGHT:
            y = image_height - y - h;
            goto progress_a;
        case ORIENTATION_BOTLEFT:
            y = image_height - y - h;
            goto progress_a;
          progress_a:
            __imlib_LoadProgress(img->image, x, y, w, h);
            break;

        case ORIENTATION_LEFTTOP:
            y = image_width - 1 - y;
            goto progress_b;
        case ORIENTATION_RIGHTTOP:
            y = y + 1 - h;
            goto progress_b;
        case ORIENTATION_RIGHTBOT:
            y = image_width - y - h;
            goto progress_b;
        case ORIENTATION_LEFTBOT:
            goto progress_b;
          progress_b:
            __imlib_LoadProgress(img->image, y, x, h, w);
            break;
        }
    }
}

static void
put_contig_and_raster(TIFFRGBAImage *img, uint32_t *rast,
                      uint32_t x, uint32_t y, uint32_t w, uint32_t h,
                      int32_t fromskew, int32_t toskew, unsigned char *cp)
{
    ((TIFFRGBAImage_Extra *) img)->put_contig(img, rast, x, y, w, h,
                                              fromskew, toskew, cp);
    raster((TIFFRGBAImage_Extra *) img, rast, x, y, w, h);
}

static void
put_separate_and_raster(TIFFRGBAImage *img, uint32_t *rast,
                        uint32_t x, uint32_t y, uint32_t w, uint32_t h,
                        int32_t fromskew, int32_t toskew,
                        unsigned char *r, unsigned char *g, unsigned char *b,
                        unsigned char *a)
{
    ((TIFFRGBAImage_Extra *) img)->put_separate(img, rast, x, y, w, h,
                                                fromskew, toskew, r, g, b, a);
    raster((TIFFRGBAImage_Extra *) img, rast, x, y, w, h);
}

static int
_sig_check(const uint8_t *data, unsigned int size)
{
    if (size < 8)
        return 1;

    if (data[0] == 'I' && data[1] == 'I')
        return !(data[2] == 42 && data[3] == 0);
    if (data[0] == 'M' && data[1] == 'M')
        return !(data[2] == 0 && data[3] == 42);

    return 1;
}

static int
_load(ImlibImage *im, int load_data)
{
    int             rc;
    TIFF           *tif = NULL;
    TIFFRGBAImage_Extra rgba_image;
    uint32_t       *rast = NULL;
    char            txt[1024];

    rc = LOAD_FAIL;
    rgba_image.image = NULL;

    /* Signature check */
    if (_sig_check(im->fi->fdata, im->fi->fsize))
        goto quit;

    mm_init(im->fi->fdata, im->fi->fsize);

    TIFFSetErrorHandler(_tiff_error);
    TIFFSetWarningHandler(_tiff_error);

    tif = TIFFClientOpen(im->fi->name, "r", NULL, _tiff_read, _tiff_write,
                         _tiff_seek, _tiff_close, _tiff_size,
                         _tiff_map, _tiff_unmap);
    if (!tif)
        goto quit;

    strcpy(txt, "Cannot be processed by libtiff");
    if (!TIFFRGBAImageOK(tif, txt))
        goto quit;

    rc = LOAD_BADIMAGE;         /* Format accepted */

    strcpy(txt, "Cannot begin reading tiff");
    if (!TIFFRGBAImageBegin((TIFFRGBAImage *) & rgba_image, tif, 1, txt))
        goto quit;

    rgba_image.image = im;

    if (!rgba_image.rgba.put.any)
    {
        E("No put function\n");
        goto quit;
    }

    switch (rgba_image.rgba.orientation)
    {
    default:
    case ORIENTATION_TOPLEFT:
    case ORIENTATION_TOPRIGHT:
    case ORIENTATION_BOTRIGHT:
    case ORIENTATION_BOTLEFT:
        im->w = rgba_image.rgba.width;
        im->h = rgba_image.rgba.height;
        break;
    case ORIENTATION_LEFTTOP:
    case ORIENTATION_RIGHTTOP:
    case ORIENTATION_RIGHTBOT:
    case ORIENTATION_LEFTBOT:
        im->w = rgba_image.rgba.height;
        im->h = rgba_image.rgba.width;
        break;
    }
    if (!IMAGE_DIMENSIONS_OK(im->w, im->h))
        goto quit;

    im->has_alpha = rgba_image.rgba.alpha != EXTRASAMPLE_UNSPECIFIED;

    if (!load_data)
        QUIT_WITH_RC(LOAD_SUCCESS);

    /* Load data */

    if (!__imlib_AllocateData(im))
        QUIT_WITH_RC(LOAD_OOM);

    rast = _TIFFmalloc(sizeof(uint32_t) * im->w * im->h);
    if (!rast)
        QUIT_WITH_RC(LOAD_OOM);

    if (rgba_image.rgba.isContig)
    {
        rgba_image.put_contig = rgba_image.rgba.put.contig;
        rgba_image.rgba.put.contig = put_contig_and_raster;
    }
    else
    {
        rgba_image.put_separate = rgba_image.rgba.put.separate;
        rgba_image.rgba.put.separate = put_separate_and_raster;
    }

    if (!TIFFRGBAImageGet((TIFFRGBAImage *) & rgba_image, rast,
                          rgba_image.rgba.width, rgba_image.rgba.height))
        goto quit;

    rc = LOAD_SUCCESS;

  quit:
    if (rast)
        _TIFFfree(rast);
    if (rgba_image.image)
        TIFFRGBAImageEnd((TIFFRGBAImage *) & rgba_image);
    if (tif)
        TIFFClose(tif);

    return rc;
}

/* this seems to work, except the magic number isn't written. I'm guessing */
/* this is a problem in libtiff */

static int
_save(ImlibImage *im)
{
    int             rc;
    TIFF           *tif = NULL;
    uint8_t        *buf = NULL;
    const uint32_t *imdata;
    uint32_t        pixel;
    double          alpha_factor;
    int             x, y;
    uint8_t         r, g, b, a = 0;
    int             has_alpha = im->has_alpha;
    int             compression_type;
    int             i;
    ImlibImageTag  *tag;

    TIFFSetErrorHandler(_tiff_error);
    TIFFSetWarningHandler(_tiff_error);

    tif = TIFFFdOpen(fileno(im->fi->fp), im->fi->name, "w");
    if (!tif)
        return LOAD_BADFILE;

    rc = LOAD_BADFILE;

    /* None of the TIFFSetFields are checked for errors, but since they */
    /* shouldn't fail, this shouldn't be a problem */

    TIFFSetField(tif, TIFFTAG_IMAGELENGTH, im->h);
    TIFFSetField(tif, TIFFTAG_IMAGEWIDTH, im->w);
    TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_RGB);
    TIFFSetField(tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
    TIFFSetField(tif, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
    TIFFSetField(tif, TIFFTAG_RESOLUTIONUNIT, RESUNIT_NONE);

    /* look for tags attached to image to get extra parameters like quality */
    /* settings etc. - this is the "api" to hint for extra information for */
    /* saver modules */

    /* compression */
    compression_type = COMPRESSION_ADOBE_DEFLATE;
    tag = __imlib_GetTag(im, "compression_type");
    if (tag)
    {
        switch (tag->val)
        {
        default:
            break;
        case COMPRESSION_NONE:
        case COMPRESSION_CCITTRLE:
        case COMPRESSION_CCITTFAX3:
        case COMPRESSION_CCITTFAX4:
        case COMPRESSION_LZW:
        case COMPRESSION_OJPEG:
        case COMPRESSION_JPEG:
        case COMPRESSION_NEXT:
        case COMPRESSION_CCITTRLEW:
        case COMPRESSION_PACKBITS:
        case COMPRESSION_THUNDERSCAN:
        case COMPRESSION_IT8CTPAD:
        case COMPRESSION_IT8LW:
        case COMPRESSION_IT8MP:
        case COMPRESSION_IT8BL:
        case COMPRESSION_PIXARFILM:
        case COMPRESSION_PIXARLOG:
        case COMPRESSION_DEFLATE:
        case COMPRESSION_ADOBE_DEFLATE:
        case COMPRESSION_DCS:
        case COMPRESSION_JBIG:
        case COMPRESSION_SGILOG:
        case COMPRESSION_SGILOG24:
            compression_type = tag->val;
            break;
        }
    }
    TIFFSetField(tif, TIFFTAG_COMPRESSION, compression_type);

    if (has_alpha)
    {
        uint16_t        extras[] = { EXTRASAMPLE_ASSOCALPHA };
        TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 4);
        TIFFSetField(tif, TIFFTAG_EXTRASAMPLES, 1, extras);
    }
    else
    {
        TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 3);
    }
    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 8);
    TIFFSetField(tif, TIFFTAG_ROWSPERSTRIP, TIFFDefaultStripSize(tif, 0));

    buf = _TIFFmalloc(TIFFScanlineSize(tif));
    if (!buf)
        QUIT_WITH_RC(LOAD_OOM);

    imdata = im->data;
    for (y = 0; y < im->h; y++)
    {
        i = 0;
        for (x = 0; x < im->w; x++)
        {
            pixel = imdata[(y * im->w) + x];

            r = PIXEL_R(pixel);
            g = PIXEL_G(pixel);
            b = PIXEL_B(pixel);
            if (has_alpha)
            {
                /* TIFF makes you pre-mutiply the rgb components by alpha */
                a = PIXEL_A(pixel);
                alpha_factor = ((double)a / 255.0);
                r *= alpha_factor;
                g *= alpha_factor;
                b *= alpha_factor;
            }

            /* This might be endian dependent */
            buf[i++] = r;
            buf[i++] = g;
            buf[i++] = b;
            if (has_alpha)
                buf[i++] = a;
        }

        if (!TIFFWriteScanline(tif, buf, y, 0))
            goto quit;

        if (im->lc && __imlib_LoadProgressRows(im, y, 1))
            QUIT_WITH_RC(LOAD_BREAK);
    }

    rc = LOAD_SUCCESS;

  quit:
    if (buf)
        _TIFFfree(buf);
    if (tif)
        TIFFClose(tif);

    return rc;
}

IMLIB_LOADER(_formats, _load, _save);