/*

 * Ensoniq Paris Audio File demuxer

 * Copyright (c) 2012 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/attributes.h"

#include "libavutil/intreadwrite.h"

#include "libavcodec/internal.h"

#include "avformat.h"

#include "demux.h"

#include "internal.h"

#include "pcm.h"

static int epaf_probe(const AVProbeData *p)

{

    if (((AV_RL32(p->buf) == MKTAG('f','a','p',' ') &&

          AV_RL32(p->buf + 8) == 1) ||

         (AV_RL32(p->buf) == MKTAG(' ','p','a','f') &&

          AV_RN32(p->buf + 8) == 0)) &&

       !AV_RN32(p->buf +  4) && AV_RN32(p->buf + 12) &&

        AV_RN32(p->buf + 20))

        return AVPROBE_SCORE_MAX / 4 * 3;

    return 0;

}

static int epaf_read_header(AVFormatContext *s)

{

    int le, sample_rate, codec, channels;

    AVStream *st;

    avio_skip(s->pb, 4);

    if (avio_rl32(s->pb))

        return AVERROR_INVALIDDATA;

    le = avio_rl32(s->pb);

    if (le && le != 1)

        return AVERROR_INVALIDDATA;

    if (le) {

        sample_rate = avio_rl32(s->pb);

        codec       = avio_rl32(s->pb);

        channels    = avio_rl32(s->pb);

    } else {

        sample_rate = avio_rb32(s->pb);

        codec       = avio_rb32(s->pb);

        channels    = avio_rb32(s->pb);

    }

    if (channels <= 0 || channels > FF_SANE_NB_CHANNELS || sample_rate <= 0)

        return AVERROR_INVALIDDATA;

    st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;

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

    st->codecpar->sample_rate = sample_rate;

    switch (codec) {

    case 0:

        st->codecpar->codec_id = le ? AV_CODEC_ID_PCM_S16LE : AV_CODEC_ID_PCM_S16BE;

        break;

    case 2:

        st->codecpar->codec_id = AV_CODEC_ID_PCM_S8;

        break;

    case 1:

        avpriv_request_sample(s, "24-bit Paris PCM format");

        av_fallthrough;

    default:

        return AVERROR_INVALIDDATA;

    }

    st->codecpar->bits_per_coded_sample = av_get_bits_per_sample(st->codecpar->codec_id);

    st->codecpar->block_align = st->codecpar->bits_per_coded_sample *

                                st->codecpar->ch_layout.nb_channels / 8;

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

    if (avio_skip(s->pb, 2024) < 0)

        return AVERROR_INVALIDDATA;

    return 0;

}

const FFInputFormat ff_epaf_demuxer = {

    .p.name         = "epaf",

    .p.long_name    = NULL_IF_CONFIG_SMALL("Ensoniq Paris Audio File"),

    .p.extensions   = "paf,fap",

    .p.flags        = AVFMT_GENERIC_INDEX,

    .read_probe     = epaf_probe,

    .read_header    = epaf_read_header,

    .read_packet    = ff_pcm_read_packet,

    .read_seek      = ff_pcm_read_seek,

};