/* poppler-cached-file-loader.h: glib interface to poppler

 *

 * Copyright (C) 2012 Carlos Garcia Campos <carlosgc@gnome.org>

 * Copyright (C) 2022 Albert Astals Cid <aacid@kde.org>

 *

 * 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, 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, write to the Free Software

 * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.

 */

#include "config.h"

#include "poppler-cached-file-loader.h"

PopplerCachedFileLoader::PopplerCachedFileLoader(GInputStream *inputStreamA, GCancellable *cancellableA, goffset lengthA)

{

    inputStream = static_cast<GInputStream *> g_object_ref(inputStreamA);

    cancellable = cancellableA ? static_cast<GCancellable *> g_object_ref(cancellableA) : nullptr;

    length = lengthA;

    cachedFile = nullptr;

}

PopplerCachedFileLoader::~PopplerCachedFileLoader()

{

    g_object_unref(inputStream);

    if (cancellable) {

        g_object_unref(cancellable);

    }

}

size_t PopplerCachedFileLoader::init(CachedFile *cachedFileA)

{

    size_t size;

    gssize bytesRead;

    char buf[CachedFileChunkSize];

    cachedFile = cachedFileA;

    if (length != static_cast<goffset>(-1)) {

        return length;

    }

    if (G_IS_FILE_INPUT_STREAM(inputStream)) {

        GFileInfo *info;

        info = g_file_input_stream_query_info(G_FILE_INPUT_STREAM(inputStream), G_FILE_ATTRIBUTE_STANDARD_SIZE, cancellable, nullptr);

        if (!info) {

            error(errInternal, -1, "Failed to get size.");

            return static_cast<size_t>(-1);

        }

        length = g_file_info_get_size(info);

        g_object_unref(info);

        return length;

    }

    // Unknown stream length, read the whole stream and return the size.

    CachedFileWriter writer = CachedFileWriter(cachedFile, nullptr);

    size = 0;

    do {

        bytesRead = g_input_stream_read(inputStream, buf, CachedFileChunkSize, cancellable, nullptr);

        if (bytesRead == -1) {

            break;

        }

        writer.write(buf, bytesRead);

        size += bytesRead;

    } while (bytesRead > 0);

    return size;

}

int PopplerCachedFileLoader::load(const std::vector<ByteRange> &ranges, CachedFileWriter *writer)

{

    char buf[CachedFileChunkSize];

    gssize bytesRead;

    size_t rangeBytesRead, bytesToRead;

    if (length == static_cast<goffset>(-1)) {

        return 0;

    }

    for (const ByteRange &range : ranges) {

        bytesToRead = MIN(CachedFileChunkSize, range.length);

        rangeBytesRead = 0;

        g_seekable_seek(G_SEEKABLE(inputStream), range.offset, G_SEEK_SET, cancellable, nullptr);

        do {

            bytesRead = g_input_stream_read(inputStream, buf, bytesToRead, cancellable, nullptr);

            if (bytesRead == -1) {

                return -1;

            }

            writer->write(buf, bytesRead);

            rangeBytesRead += bytesRead;

            bytesToRead = range.length - rangeBytesRead;

        } while (bytesRead > 0 && bytesToRead > 0);

    }

    return 0;

}