/*
 * (C) Copyright 2005- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */

#include "grib_api_internal.h"

#if HAVE_LIBJASPER
/* Remove compiler warnings re macros being redefined */
#undef PACKAGE_BUGREPORT
#undef PACKAGE_NAME
#undef PACKAGE_STRING
#undef PACKAGE_TARNAME
#undef PACKAGE_VERSION
#include "jasper/jasper.h"
#define MAXOPTSSIZE 1024

static int ecc_jasper_initialise()
{
#if JASPER_VERSION_MAJOR >= 3
    int jaserr = 0;
    jas_conf_clear();
    jas_conf_set_max_mem_usage(jas_get_total_mem_size());

    #if defined GRIB_PTHREADS || defined GRIB_OMP_THREADS
        jas_conf_set_multithread(1);
    #endif

    jaserr = jas_init_library();
    if (jaserr) return jaserr;
    jaserr = jas_init_thread();
    if (jaserr) return jaserr;
#endif
    return 0;
}

static jas_image_t* ecc_jasper_decode(jas_stream_t *in)
{
#if JASPER_VERSION_MAJOR >= 3
    /* Second argument (=fmt) < 0 means "If possible, try to determine the format of the input data" */
    return jas_image_decode(in, -1, 0);
#else
    return jpc_decode(in, NULL);
#endif
}

static int ecc_jasper_encode(jas_image_t *image, jas_stream_t *jpcstream, char *optstr)
{
#if JASPER_VERSION_MAJOR >= 3
    const int fmt = jas_image_strtofmt("jpc");
    return jas_image_encode(image, jpcstream, fmt, optstr);
#else
    return jpc_encode(image, jpcstream, optstr);
#endif
}

static void ecc_jasper_cleanup()
{
#if JASPER_VERSION_MAJOR >= 3
    jas_cleanup_thread();
    jas_cleanup_library();
#endif
}

int grib_jasper_decode(grib_context* c, unsigned char* buf, const size_t* buflen, double* values, const size_t* n_vals)
{
    /* jas_setdbglevel(99999); */
    jas_image_t* image   = NULL;
    jas_stream_t* jpeg   = NULL;
    int code             = GRIB_SUCCESS;
    jas_matrix_t* matrix = NULL;
    jas_image_cmpt_t* p;
    int i, j, k;
    int jaserr = 0; /* 0 means success */

    jaserr = ecc_jasper_initialise();
    if (jaserr) {
        grib_context_log(c, GRIB_LOG_ERROR, "grib_jasper_decode: Failed to initialize JasPer library. JasPer error %d", jaserr);
        code = GRIB_DECODING_ERROR;
        goto cleanup;
    }

    jpeg = jas_stream_memopen((char*)buf, *buflen);
    if (!jpeg) {
        code = GRIB_DECODING_ERROR;
        goto cleanup;
    }

    grib_context_log(c, GRIB_LOG_DEBUG, "grib_jasper_decode: JasPer version %s", jas_getversion());

    image = ecc_jasper_decode(jpeg);
    if (!image) {
        code = GRIB_DECODING_ERROR;
        goto cleanup;
    }

    p = image->cmpts_[0];

    if (image->numcmpts_ != 1) {
        /* Image not gray scale */
        code = GRIB_DECODING_ERROR;
        goto cleanup;
    }

    matrix = jas_matrix_create(jas_image_height(image), jas_image_width(image));
    if (!matrix) {
        code = GRIB_DECODING_ERROR;
        goto cleanup;
    }

    jaserr = jas_image_readcmpt(image, 0, 0, 0, jas_image_width(image), jas_image_height(image), matrix);
    if (jaserr) {
        grib_context_log(c, GRIB_LOG_ERROR, "grib_jasper_decode: Failed to read JasPer component data. JasPer error %d", jaserr);
        code = GRIB_DECODING_ERROR;
        goto cleanup;
    }

    Assert(p->height_ * p->width_ == *n_vals);

    k = 0;
    for (i = 0; i < p->height_; i++)
        for (j = 0; j < p->width_; j++) {
            values[k++] = matrix->rows_[i][j];
        }

cleanup:
    if (matrix)
        jas_matrix_destroy(matrix);
    if (image)
        jas_image_destroy(image);
    if (jpeg)
        jas_stream_close(jpeg);
    ecc_jasper_cleanup();

    return code;
}

int grib_jasper_encode(grib_context* c, j2k_encode_helper* helper)
{
    int code = GRIB_SUCCESS;
    int jaserr = 0;

    char opts[MAXOPTSSIZE];
    double reference_value = helper->reference_value;
    double decimal         = helper->decimal;
    double divisor         = helper->divisor;
    const double* values   = helper->values;
    long no_values         = helper->no_values;
    long bits8;
    int i;

    size_t buflen          = 0;
    unsigned char* encoded = NULL;
    unsigned char* p       = NULL;

    jas_image_t image       = { 0 };
    jas_stream_t* jpcstream = 0;
    jas_stream_t* istream   = 0;
    jas_image_cmpt_t cmpt   = {0,};
    jas_image_cmpt_t* pcmpt = 0;

    image.tlx_      = 0;
    image.tly_      = 0;
    image.brx_      = helper->width;
    image.bry_      = helper->height;
    image.numcmpts_ = 1;
    image.maxcmpts_ = 1;
    image.clrspc_   = JAS_CLRSPC_SGRAY;
    image.cmprof_   = 0;

#if JASPER_VERSION_MAJOR == 1
    /* ECC-396: Support for Jasper 2.0
     * Jasper version 1 had the 'inmem_' data member but
     * version 2 removed it from the interface */
    image.inmem_ = 1;
#endif

    cmpt.tlx_    = 0;
    cmpt.tly_    = 0;
    cmpt.hstep_  = 1;
    cmpt.vstep_  = 1;
    cmpt.width_  = helper->width;
    cmpt.height_ = helper->height;
    cmpt.type_   = JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_GRAY_Y);
    cmpt.prec_   = helper->bits_per_value;
    cmpt.sgnd_   = 0;
    cmpt.cps_    = (helper->bits_per_value + 7) / 8;

    /* Simple packing encoding */
    bits8 = (helper->bits_per_value + 7) / 8 * 8;
    Assert(bits8 > 0);
    encoded = (unsigned char*)grib_context_malloc_clear(c, bits8 / 8 * no_values);

    if (!encoded) {
        code = GRIB_OUT_OF_MEMORY;
        goto cleanup;
    }

    buflen = 0;
    p      = encoded;

    for (i = 0; i < no_values; i++) {
        long blen                  = bits8;
        unsigned long unsigned_val = (unsigned long)((((values[i] * decimal) - (reference_value)) * divisor) + 0.5);
        while (blen >= 8) {
            blen -= 8;
            *p = (unsigned_val >> blen);
            p++;
            buflen++;
        }
    }

    ecc_jasper_initialise();

    opts[0] = 0;

    if (helper->compression != 0) {
        /* Lossy */
        snprintf(opts, MAXOPTSSIZE, "mode=real\nrate=%f", 1.0 / helper->compression);
    }

    Assert(cmpt.width_ * cmpt.height_ * cmpt.cps_ == buflen);
    grib_context_log(c, GRIB_LOG_DEBUG, "grib_jasper_encode: JasPer version %s", jas_getversion());

    pcmpt        = &cmpt;
    image.cmpts_ = &pcmpt;

    istream      = jas_stream_memopen((char*)encoded, buflen);
    cmpt.stream_ = istream;

    jpcstream = jas_stream_memopen((char*)helper->jpeg_buffer, helper->buffer_size);

    jaserr = ecc_jasper_encode(&image, jpcstream, opts);
    if (jaserr) {
        /* Failed to encode. Increase the number of guard bits */
        strcat(opts, "\nnumgbits=4");
        grib_context_log(c, GRIB_LOG_ERROR, "grib_jasper_encode: JasPer error %d, increasing the number of guard bits", jaserr);
        jas_stream_close(istream);
        istream = 0;
        jas_stream_close(jpcstream);
        jpcstream = 0;

        istream      = jas_stream_memopen((char*)encoded, buflen);
        cmpt.stream_ = istream;
        jpcstream    = jas_stream_memopen((char*)helper->jpeg_buffer, helper->buffer_size);
        jaserr       = ecc_jasper_encode(&image, jpcstream, opts);
    }

    if (jaserr) {
        grib_context_log(c, GRIB_LOG_ERROR, "grib_jasper_encode: Failed to encode. JasPer error %d", jaserr);
        code = GRIB_ENCODING_ERROR;
        goto cleanup;
    }

    helper->jpeg_length = jpcstream->rwcnt_;
    jas_stream_close(istream);
    istream             = 0;
    jas_stream_close(jpcstream);
    jpcstream           = 0;

cleanup:
    grib_context_free(c, encoded);
    if (istream)
        jas_stream_close(istream);
    if (jpcstream)
        jas_stream_close(jpcstream);
    ecc_jasper_cleanup();
    return code;
}

#else // HAVE_LIBJASPER

int grib_jasper_decode(grib_context* c, unsigned char* buf, const size_t* buflen, double* val, const size_t* n_vals)
{
    grib_context_log(c, GRIB_LOG_ERROR, "grib_jasper_decode: JasPer JPEG support not enabled.");
    return GRIB_FUNCTIONALITY_NOT_ENABLED;
}

int grib_jasper_encode(grib_context* c, j2k_encode_helper* helper)
{
    grib_context_log(c, GRIB_LOG_ERROR, "grib_jasper_encode: JasPer JPEG support not enabled.");
    return GRIB_FUNCTIONALITY_NOT_ENABLED;
}

#endif