/*******************************************************
 * Copyright (c) 2014, ArrayFire
 * All rights reserved.
 *
 * This file is distributed under 3-clause BSD license.
 * The complete license agreement can be obtained at:
 * http://arrayfire.com/licenses/BSD-3-Clause
 ********************************************************/

#include <af/defines.h>
#include <af/array.h>
#include <af/image.h>
#include <err_common.hpp>

template<af_cspace_t FROM, af_cspace_t TO>
void color_space(af_array *out, const af_array image)
{
    AF_ERROR("Color Space: Conversion from source type to output type not supported",
             AF_ERR_NOT_SUPPORTED);
}

#define INSTANTIATE_CSPACE_DEFS1(F, T, FUNC)                    \
template<>                                                      \
void color_space<F, T>(af_array *out, const af_array image)     \
{                                                               \
    AF_CHECK(FUNC(out, image));                                 \
}

#define INSTANTIATE_CSPACE_DEFS2(F, T, FUNC, ...)               \
template<>                                                      \
void color_space<F, T>(af_array *out, const af_array image)     \
{                                                               \
    AF_CHECK(FUNC(out, image, __VA_ARGS__));                    \
}

INSTANTIATE_CSPACE_DEFS1(AF_HSV  , AF_RGB  , af_hsv2rgb  );
INSTANTIATE_CSPACE_DEFS1(AF_RGB  , AF_HSV  , af_rgb2hsv  );
INSTANTIATE_CSPACE_DEFS2(AF_RGB  , AF_GRAY , af_rgb2gray , 0.2126f, 0.7152f, 0.0722f);
INSTANTIATE_CSPACE_DEFS2(AF_GRAY , AF_RGB  , af_gray2rgb , 1.0f, 1.0f, 1.0f);
INSTANTIATE_CSPACE_DEFS2(AF_YCbCr, AF_RGB  , af_ycbcr2rgb, AF_YCC_601);
INSTANTIATE_CSPACE_DEFS2(AF_RGB  , AF_YCbCr, af_rgb2ycbcr, AF_YCC_601);

template<af_cspace_t FROM>
static void color_space(af_array *out, const af_array image, const af_cspace_t to)
{
    switch(to) {
        case AF_GRAY : color_space<FROM, AF_GRAY >(out, image);     break;
        case AF_RGB  : color_space<FROM, AF_RGB  >(out, image);     break;
        case AF_HSV  : color_space<FROM, AF_HSV  >(out, image);     break;
        case AF_YCbCr: color_space<FROM, AF_YCbCr>(out, image);     break;
        default: AF_ERROR("Incorrect enum value for output color type", AF_ERR_ARG);
    }
}

af_err af_color_space(af_array *out, const af_array image, const af_cspace_t to, const af_cspace_t from)
{
    try {
        if (from == to) {
            return af_retain_array(out, image);
        }

        ARG_ASSERT(2, (to == AF_GRAY || to == AF_RGB || to == AF_HSV || to == AF_YCbCr));
        ARG_ASSERT(2, (from == AF_GRAY || from == AF_RGB || from == AF_HSV || from == AF_YCbCr));

        switch(from) {
            case AF_GRAY : color_space<AF_GRAY >(out, image, to);   break;
            case AF_RGB  : color_space<AF_RGB  >(out, image, to);   break;
            case AF_HSV  : color_space<AF_HSV  >(out, image, to);   break;
            case AF_YCbCr: color_space<AF_YCbCr>(out, image, to);   break;
            default: AF_ERROR("Incorrect enum value for input color type", AF_ERR_ARG);
        }
    }
    CATCHALL;

    return AF_SUCCESS;
}
