/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */

/*

 * This file is part of the LibreOffice project.

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 */

#include <cstring>

#include <InflaterBytesZlib.hxx>

#include <string.h>

#include <zlib.h>

using namespace ZipUtils;

InflaterBytesZlib::InflaterBytesZlib()

    : bFinished(false),

      nOffset(0),

      nLength(0),

      sInBuffer(nullptr),

      pStream(std::make_unique<z_stream>())

{

    memset(pStream.get(), 0, sizeof(*pStream));

    sal_Int32 nRes = inflateInit2(pStream.get(), -MAX_WBITS);

    switch (nRes)

    {

        case Z_OK:

            break;

        case Z_MEM_ERROR:

        case Z_STREAM_ERROR:

            pStream.reset();

            break;

        default:

            break;

    }

}

InflaterBytesZlib::~InflaterBytesZlib() { end(); }

void InflaterBytesZlib::setInput(const sal_Int8* rBuffer, sal_Int32 nBufLen)

{

    sInBuffer = rBuffer;

    nOffset   = 0;

    nLength   = nBufLen;

}

sal_Int32 InflaterBytesZlib::doInflateSegment(sal_Int8* pOutBuffer, sal_Int32 nBufLen, sal_Int32 nNewOffset, sal_Int32 nNewLength)

{

    if (nNewOffset < 0 || nNewLength < 0 || nNewOffset + nNewLength > nBufLen)

    {

        return 0;

    }

    return doInflateBytes(pOutBuffer, nNewOffset, nNewLength);

}

void InflaterBytesZlib::end()

{

    if (pStream)

    {

#if !defined Z_PREFIX

        inflateEnd(pStream.get());

#else

        z_inflateEnd(pStream.get());

#endif

        pStream.reset();

    }

}

sal_Int32 InflaterBytesZlib::doInflateBytes(sal_Int8* pOutBuffer, sal_Int32 nNewOffset, sal_Int32 nNewLength)

{

    if (!pStream)

        return 0;

    pStream->next_in   = reinterpret_cast<const unsigned char*>(sInBuffer + nOffset);

    pStream->avail_in  = nLength;

    pStream->next_out  = reinterpret_cast<unsigned char*>(pOutBuffer + nNewOffset);

    pStream->avail_out = nNewLength;

#if !defined Z_PREFIX

    sal_Int32 nResult = ::inflate(pStream.get(), Z_PARTIAL_FLUSH);

#else

    sal_Int32 nResult = ::z_inflate(pStream.get(), Z_PARTIAL_FLUSH);

#endif

    switch (nResult)

    {

        case Z_STREAM_END:

            bFinished = true;

            [[fallthrough]];

        case Z_OK:

            nOffset += nLength - pStream->avail_in;

            nLength = pStream->avail_in;

            return nNewLength - pStream->avail_out;

        case Z_NEED_DICT:

            nOffset += nLength - pStream->avail_in;

            nLength = pStream->avail_in;

            return 0;

        default:

            break;

    }

    return 0;

}

/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */