/*
 * Copyright (C) 2001-2019 Jacek Sieka, arnetheduck on gmail point com
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "stdinc.h"
#include "BZUtils.h"

#include <cstring>

#include "Exception.h"
#include "format.h"

namespace dcpp {

using std::max;

BZFilter::BZFilter() {
    memset(&zs, 0, sizeof(zs));

    if(BZ2_bzCompressInit(&zs, 9, 0, 30) != BZ_OK) {
        throw Exception(_("Error during compression"));
    }
}

BZFilter::~BZFilter() {
    dcdebug("BZFilter end, %u/%u = %.04f\n", zs.total_out_lo32, zs.total_in_lo32, (float)zs.total_out_lo32 / max((float)zs.total_in_lo32, (float)1));
    BZ2_bzCompressEnd(&zs);
}

bool BZFilter::operator()(const void* in, size_t& insize, void* out, size_t& outsize) {
    if(outsize == 0)
        return false;

    zs.avail_in = insize;
    zs.next_in = (char*)in;
    zs.avail_out = outsize;
    zs.next_out = (char*)out;

    if(insize == 0) {
        int err = ::BZ2_bzCompress(&zs, BZ_FINISH);
        if(err != BZ_FINISH_OK && err != BZ_STREAM_END)
            throw Exception(_("Error during compression"));

        outsize = outsize - zs.avail_out;
        insize = insize - zs.avail_in;
        return err == BZ_FINISH_OK;
    } else {
        int err = ::BZ2_bzCompress(&zs, BZ_RUN);
        if(err != BZ_RUN_OK)
            throw Exception(_("Error during compression"));

        outsize = outsize - zs.avail_out;
        insize = insize - zs.avail_in;
        return true;
    }
}

UnBZFilter::UnBZFilter() {
    memset(&zs, 0, sizeof(zs));

    if(BZ2_bzDecompressInit(&zs, 0, 0) != BZ_OK)
        throw Exception(_("Error during decompression"));

}

UnBZFilter::~UnBZFilter() {
    dcdebug("UnBZFilter end, %u/%u = %.04f\n", zs.total_out_lo32, zs.total_in_lo32, (float)zs.total_out_lo32 / max((float)zs.total_in_lo32, (float)1));
    BZ2_bzDecompressEnd(&zs);
}

bool UnBZFilter::operator()(const void* in, size_t& insize, void* out, size_t& outsize) {
    if(outsize == 0)
        return false;

    zs.avail_in = insize;
    zs.next_in = (char*)in;
    zs.avail_out = outsize;
    zs.next_out = (char*)out;

    int err = ::BZ2_bzDecompress(&zs);

    // No more input data, and inflate didn't think it has reached the end...
    if(insize == 0 && zs.avail_out != 0 && err != BZ_STREAM_END)
        throw Exception(_("Error during decompression"));

    if(err != BZ_OK && err != BZ_STREAM_END)
        throw Exception(_("Error during decompression"));

    outsize = outsize - zs.avail_out;
    insize = insize - zs.avail_in;
    return err == BZ_OK;
}

} // namespace dcpp
