/*

 * SDR2 demuxer

 * Copyright (c) 2014 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/intreadwrite.h"

#include "avformat.h"

#include "demux.h"

#include "internal.h"

static int sdr2_probe(const AVProbeData *p)

{

    if (AV_RL32(p->buf) != MKTAG('S', 'R', 'A', 1))

        return 0;

    return AVPROBE_SCORE_EXTENSION;

}

#define FIRST 0xA8

static int sdr2_read_header(AVFormatContext *s)

{

    AVStream *st, *ast;

    ast = avformat_new_stream(s, 0);

    if (!ast)

        return AVERROR(ENOMEM);

    st = avformat_new_stream(s, 0);

    if (!st)

        return AVERROR(ENOMEM);

    avio_skip(s->pb, 20);

    avpriv_set_pts_info(st, 64, 1, avio_rl32(s->pb));

    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;

    st->codecpar->width      = avio_rl32(s->pb);

    st->codecpar->height     = avio_rl32(s->pb);

    st->codecpar->codec_id   = AV_CODEC_ID_H264;

    ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL;

    ast->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;

    ast->codecpar->ch_layout.nb_channels = 1;

    ast->codecpar->sample_rate = 8000;

    ast->codecpar->codec_id    = AV_CODEC_ID_PCM_S16LE;

    avpriv_set_pts_info(ast, 64, 1, 8000);

    avio_seek(s->pb, FIRST, SEEK_SET);

    return 0;

}

static const uint8_t header[24] = {

    0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0x00, 0x1e,

    0xa6, 0x80, 0xb0, 0x7e, 0x40, 0x00, 0x00, 0x00,

    0x01, 0x68, 0xce, 0x38, 0x80, 0x00, 0x00, 0x00

};

static int sdr2_read_packet(AVFormatContext *s, AVPacket *pkt)

{

    int64_t pos;

    unsigned next;

    int flags, ret = 0, is_video;

    pos = avio_tell(s->pb);

    flags = avio_rl32(s->pb);

    avio_skip(s->pb, 4);

    next = avio_rl32(s->pb);

    if (next <= 52)

        return AVERROR_INVALIDDATA;

    avio_skip(s->pb, 6);

    is_video = avio_rl32(s->pb);

    avio_skip(s->pb, 30);

    if (pos == FIRST) {

        if ((ret = av_new_packet(pkt, next - 52 + 24)) < 0)

            return ret;

        memcpy(pkt->data, header, 24);

        ret = avio_read(s->pb, pkt->data + 24, next - 52);

        if (ret < 0) {

            return ret;

        }

        av_shrink_packet(pkt, ret + 24);

    } else {

        ret = av_get_packet(s->pb, pkt, next - 52);

    }

    pkt->stream_index = !!is_video;

    pkt->pos = pos;

    if (flags & (1 << 12))

        pkt->flags |= AV_PKT_FLAG_KEY;

    return ret;

}

const FFInputFormat ff_sdr2_demuxer = {

    .p.name      = "sdr2",

    .p.long_name = NULL_IF_CONFIG_SMALL("SDR2"),

    .p.extensions= "sdr2",

    .p.flags     = AVFMT_GENERIC_INDEX,

    .read_probe  = sdr2_probe,

    .read_header = sdr2_read_header,

    .read_packet = sdr2_read_packet,

};