/* ============================================================
 *
 * This file is a part of digiKam project
 * https://www.digikam.org
 *
 * Date        : 2023-05-15
 * Description : geolocation engine based on Marble.
 *               (c) 2007-2022 Marble Team
 *               https://invent.kde.org/education/marble/-/raw/master/data/credits_authors.html
 *
 * SPDX-FileCopyrightText: 2023-2026 by Gilles Caulier <caulier dot gilles at gmail dot com>
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later
 *
 * ============================================================ */

#include "OsmPbfParser.h"

#ifdef HAVE_PROTOBUF
#   include "fileformat.pb.h"
#   include "osmformat.pb.h"
#endif

// ZLib includes

#include <zlib.h>

// C++ includes

#include <cstdint>
#include <cstring>

// Qt includes

#include <QDebug>
#include <QtEndian>

// KDE includes

#include <klocalizedstring.h>

namespace Marble
{

void OsmPbfParser::parse(const uint8_t* data, std::size_t len)
{

#ifdef HAVE_PROTOBUF

    const uint8_t* it = data;
    const uint8_t* end = data + len;

    while (parseBlob(it, end));

#else

    Q_UNUSED(data);
    Q_UNUSED(len);

#endif

}

#ifdef HAVE_PROTOBUF

bool OsmPbfParser::parseBlob(const uint8_t*& it, const uint8_t* end)
{
    if (std::distance(it, end) < (int)sizeof(int32_t))
    {
        return false;
    }

    int32_t blobHeaderSize = 0;
    std::memcpy(&blobHeaderSize, it, sizeof(int32_t));
    blobHeaderSize = qFromBigEndian(blobHeaderSize);
    it += sizeof(int32_t);

    if (blobHeaderSize < 0 || std::distance(it, end) < blobHeaderSize)
    {
        return false;
    }

    OSMPBF::BlobHeader blobHeader;

    if (!blobHeader.ParseFromArray(it, blobHeaderSize))
    {
        return false;
    }

    it += blobHeaderSize;

    OSMPBF::Blob blob;

    if (std::distance(it, end) < blobHeader.datasize() || !blob.ParseFromArray(it, blobHeader.datasize()))
    {
        return false;
    }

    const uint8_t* dataBegin = nullptr;

    if (blob.has_raw())
    {
        dataBegin = reinterpret_cast<const uint8_t*>(blob.raw().data());
    }

    else if (blob.has_zlib_data())
    {
        m_zlibBuffer.resize(blob.raw_size());
        z_stream zStream;
        zStream.next_in = (uint8_t*)blob.zlib_data().data();
        zStream.avail_in = blob.zlib_data().size();
        zStream.next_out = (uint8_t*)m_zlibBuffer.data();
        zStream.avail_out = blob.raw_size();
        zStream.zalloc = nullptr;
        zStream.zfree = nullptr;
        zStream.opaque = nullptr;
        auto result = inflateInit(&zStream);

        if (result != Z_OK)
        {
            return false;
        }

        result = inflate(&zStream, Z_FINISH);

        if (result != Z_STREAM_END)
        {
            return false;
        }

        result = inflateEnd(&zStream);
        dataBegin = reinterpret_cast<const uint8_t*>(m_zlibBuffer.constData());
    }

    else
    {
        return false;
    }

    if (std::strcmp(blobHeader.type().c_str(), "OSMData") == 0)
    {
        parsePrimitiveBlock(dataBegin, blob.raw_size());
    }

    m_zlibBuffer.clear();
    it += blobHeader.datasize();
    return true;
}

void OsmPbfParser::parsePrimitiveBlock(const uint8_t* data, std::size_t len)
{
    OSMPBF::PrimitiveBlock block;

    if (!block.ParseFromArray(data, len))
    {
        return;
    }

    for (int i = 0; i < block.primitivegroup_size(); ++i)
    {
        const auto& group = block.primitivegroup(i);

        if (group.nodes_size())
        {
            qCWarning(DIGIKAM_GEOENGINE_LOG) << QString::fromUtf8() << "non-dense nodes - not implemented yet!";
        }

        else if (group.has_dense())
        {
            parseDenseNodes(block, group);
        }

        else if (group.ways_size())
        {
            parseWays(block, group);
        }

        else if (group.relations_size())
        {
            parseRelations(block, group);
        }
    }
}

void OsmPbfParser::parseDenseNodes(const OSMPBF::PrimitiveBlock& block, const OSMPBF::PrimitiveGroup& group)
{
    int64_t idDelta = 0;
    int64_t latDelta = 0;
    int64_t lonDelta = 0;
    int tagIdx = 0;

    const auto dense = group.dense();

    for (int i = 0; i < dense.id_size(); ++i)
    {
        idDelta += dense.id(i);
        latDelta += dense.lat(i);
        lonDelta += dense.lon(i);

        auto& node = m_nodes[idDelta];
        node.osmData().setId(idDelta);
        node.setCoordinates(GeoDataCoordinates(lonDelta * 1.0e-7, latDelta * 1.0e-7, 0.0, GeoDataCoordinates::Degree));

        while (tagIdx < dense.keys_vals_size())
        {
            const auto keyIdx = dense.keys_vals(tagIdx++);

            if (keyIdx == 0)
            {
                break;
            }

            const auto valIdx = dense.keys_vals(tagIdx++);
            const QString keyString = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(keyIdx).data()));
            const QString valueString = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(valIdx).data()));
            node.osmData().addTag(keyString, valueString);
        }
    }
}

void OsmPbfParser::parseWays(const OSMPBF::PrimitiveBlock& block, const OSMPBF::PrimitiveGroup& group)
{
    for (int i = 0; i < group.ways_size(); ++i)
    {
        const auto& w = group.ways(i);
        auto& way = m_ways[w.id()];
        way.osmData().setId(w.id());

        int64_t idDelta = 0;

        for (int j = 0; j < w.refs_size(); ++j)
        {
            idDelta += w.refs(j);
            way.addReference(idDelta);
        }

        for (int j = 0; j < w.keys_size(); ++j)
        {
            const QString keyString = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(w.keys(j)).data()));
            const QString valueString = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(w.vals(j)).data()));
            way.osmData().addTag(keyString, valueString);
        }
    }
}

void OsmPbfParser::parseRelations(const OSMPBF::PrimitiveBlock& block, const OSMPBF::PrimitiveGroup& group)
{
    for (int i = 0; i < group.relations_size(); ++i)
    {
        const auto& r = group.relations(i);

        auto& rel = m_relations[r.id()];
        rel.osmData().setId(r.id());

        int64_t idDelta = 0;

        for (int j = 0; j < r.memids_size(); ++j)
        {
            idDelta += r.memids(j);
            const QString role = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(r.roles_sid(j)).data()));
            QString typeName;
            const auto type = r.types(j);

            switch (type)
            {
                case OSMPBF::Relation_MemberType_NODE:
                    typeName = QStringLiteral("node");
                    break;

                case OSMPBF::Relation_MemberType_WAY:
                    typeName = QStringLiteral("way");
                    break;

                case OSMPBF::Relation_MemberType_RELATION:
                    typeName = QStringLiteral("relation");
                    break;
            }

            rel.addMember(idDelta, role, typeName);
        }

        for (int j = 0; j < r.keys_size(); ++j)
        {
            const QString keyString = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(r.keys(j)).data()));
            const QString valueString = *m_stringPool.insert(QString::fromUtf8(block.stringtable().s(r.vals(j)).data()));
            rel.osmData().addTag(keyString, valueString);
        }
    }
}

#endif // HAVE_PROTOBUF

} // namespace Marble
