/*

 * NSP demuxer

 * Copyright (c) 2017 Paul B Mahol

 *

 * 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 "libavutil/avstring.h"

#include "libavutil/intreadwrite.h"

#include "avformat.h"

#include "demux.h"

#include "internal.h"

#include "pcm.h"

static int nsp_probe(const AVProbeData *p)

{

    if (AV_RB32(p->buf) == AV_RB32("FORM") &&

        AV_RB32(p->buf + 4) == AV_RB32("DS16"))

        return AVPROBE_SCORE_MAX;

    return 0;

}

static int nsp_read_header(AVFormatContext *s)

{

    int channels = 0, rate = 0;

    uint32_t chunk, size;

    AVStream *st;

    int64_t pos;

    avio_skip(s->pb, 12);

    st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    while (!avio_feof(s->pb)) {

        char value[1024];

        chunk = avio_rb32(s->pb);

        size  = avio_rl32(s->pb);

        pos   = avio_tell(s->pb);

        switch (chunk) {

        case MKBETAG('H', 'E', 'D', 'R'):

        case MKBETAG('H', 'D', 'R', '8'):

            if (size < 32)

                return AVERROR_INVALIDDATA;

            avio_skip(s->pb, 20);

            rate = avio_rl32(s->pb);

            avio_skip(s->pb, size - (avio_tell(s->pb) - pos));

            break;

        case MKBETAG('N', 'O', 'T', 'E'):

            avio_get_str(s->pb, size, value, sizeof(value));

            av_dict_set(&s->metadata, "Comment", value, 0);

            avio_skip(s->pb, size & 1);

            break;

        case MKBETAG('S', 'D', 'A', 'B'):

            channels = 2;

            break;

        case MKBETAG('S', 'D', '_', '2'):

        case MKBETAG('S', 'D', '_', '3'):

        case MKBETAG('S', 'D', '_', '4'):

        case MKBETAG('S', 'D', '_', '5'):

        case MKBETAG('S', 'D', '_', '6'):

        case MKBETAG('S', 'D', '_', '7'):

        case MKBETAG('S', 'D', '_', '8'):

            av_log(s, AV_LOG_WARNING, "Unsupported chunk!\n");

        case MKBETAG('S', 'D', 'A', '_'):

        case MKBETAG('S', 'D', '_', 'A'):

            channels = 1;

            break;

        }

        if (channels)

            break;

    }

    st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;

    st->codecpar->ch_layout.nb_channels = channels;

    st->codecpar->sample_rate = rate;

    st->codecpar->codec_id    = AV_CODEC_ID_PCM_S16LE;

    st->codecpar->block_align = 2 * channels;

    return 0;

}

const FFInputFormat ff_nsp_demuxer = {

    .p.name         = "nsp",

    .p.long_name    = NULL_IF_CONFIG_SMALL("Computerized Speech Lab NSP"),

    .p.extensions   = "nsp",

    .p.flags        = AVFMT_GENERIC_INDEX,

    .read_probe     = nsp_probe,

    .read_header    = nsp_read_header,

    .read_packet    = ff_pcm_read_packet,

    .read_seek      = ff_pcm_read_seek,

};