/*

 * ADP demuxer

 * Copyright (c) 2013 James Almer

 *

 * 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/channel_layout.h"

#include "libavutil/intreadwrite.h"

#include "avformat.h"

#include "demux.h"

#include "internal.h"

static int adp_probe(const AVProbeData *p)

{

    int i, changes = 0;

    uint8_t last = 0;

    if (p->buf_size < 32)

        return 0;

    for (i = 0; i < p->buf_size - 3; i+=32) {

        if (p->buf[i] != p->buf[i+2] || p->buf[i+1] != p->buf[i+3])

            return 0;

        if (p->buf[i] != last)

            changes++;

        last = p->buf[i];

    }

    if (changes <= 1)

        return 0;

    return p->buf_size < 260 ? 1 : AVPROBE_SCORE_MAX / 4;

}

static int adp_read_header(AVFormatContext *s)

{

    AVStream *st;

    st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    st->codecpar->codec_type     = AVMEDIA_TYPE_AUDIO;

    st->codecpar->codec_id       = AV_CODEC_ID_ADPCM_DTK;

    st->codecpar->ch_layout      = (AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO;

    st->codecpar->sample_rate    = 48000;

    st->start_time            = 0;

    if (s->pb->seekable & AVIO_SEEKABLE_NORMAL)

        st->duration          = av_get_audio_frame_duration2(st->codecpar, avio_size(s->pb));

    avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);

    return 0;

}

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

{

    int ret, size = 1024;

    if (avio_feof(s->pb))

        return AVERROR_EOF;

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

    if (ret < 0)

        return ret;

    pkt->stream_index = 0;

    return ret;

}

const FFInputFormat ff_adp_demuxer = {

    .p.name         = "adp",

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

    .p.extensions   = "adp,dtk",

    .read_probe     = adp_probe,

    .read_header    = adp_read_header,

    .read_packet    = adp_read_packet,

};