/*

 * Shorten demuxer

 * Copyright (c) 2001 Fabrice Bellard

 * Copyright (c) 2005 Alex Beregszaszi

 * Copyright (c) 2015 Carl Eugen Hoyos

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

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

 */

#include "avformat.h"

#include "demux.h"

#include "rawdec.h"

#include "libavcodec/golomb.h"

static int shn_probe(const AVProbeData *p)

{

    GetBitContext gb;

    int version, internal_ftype, channels, blocksize;

    if (AV_RB32(p->buf) != 0x616a6b67)

        return 0;

    version = p->buf[4];

    if (init_get_bits8(&gb, p->buf + 5, p->buf_size - 5 - AV_INPUT_BUFFER_PADDING_SIZE) < 0)

        return 0;

    if (!version) {

        internal_ftype = get_ur_golomb_shorten(&gb, 4);

        channels = get_ur_golomb_shorten(&gb, 0);

        blocksize = 256;

    } else {

        unsigned k;

        k = get_ur_golomb_shorten(&gb, 2);

        if (k > 31)

            return 0;

        internal_ftype = get_ur_golomb_shorten(&gb, k);

        k = get_ur_golomb_shorten(&gb, 2);

        if (k > 31)

            return 0;

        channels = get_ur_golomb_shorten(&gb, k);

        k = get_ur_golomb_shorten(&gb, 2);

        if (k > 31)

            return 0;

        blocksize = get_ur_golomb_shorten(&gb, k);

    }

    if (internal_ftype != 2 && internal_ftype != 3 && internal_ftype != 5)

        return 0;

    if (channels < 1 || channels > 8)

        return 0;

    if (blocksize < 1 || blocksize > 65535)

        return 0;

    return AVPROBE_SCORE_EXTENSION + 1;

}

const FFInputFormat ff_shorten_demuxer = {

    .p.name         = "shn",

    .p.long_name    = NULL_IF_CONFIG_SMALL("raw Shorten"),

    .p.flags        = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK | AVFMT_NOTIMESTAMPS,

    .p.extensions   = "shn",

    .p.priv_class   = &ff_raw_demuxer_class,

    .read_probe     = shn_probe,

    .read_header    = ff_raw_audio_read_header,

    .read_packet    = ff_raw_read_partial_packet,

    .raw_codec_id   = AV_CODEC_ID_SHORTEN,

    .priv_data_size = sizeof(FFRawDemuxerContext),

};