/*

 * RAW aptX demuxer

 *

 * Copyright (C) 2017  Aurelien Jacobs <aurel@gnuage.org>

 *

 * 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 "config_components.h"

#include "libavutil/opt.h"

#include "avformat.h"

#include "demux.h"

#define APTX_BLOCK_SIZE   4

#define APTX_PACKET_SIZE  (256*APTX_BLOCK_SIZE)

#define APTX_HD_BLOCK_SIZE   6

#define APTX_HD_PACKET_SIZE  (256*APTX_HD_BLOCK_SIZE)

typedef struct AptXDemuxerContext {

    AVClass *class;

    int sample_rate;

} AptXDemuxerContext;

static AVStream *aptx_read_header_common(AVFormatContext *s)

{

    AptXDemuxerContext *s1 = s->priv_data;

    AVStream *st = avformat_new_stream(s, NULL);

    if (!st)

        return NULL;

    st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;

    st->codecpar->format = AV_SAMPLE_FMT_S32P;

    st->codecpar->ch_layout.nb_channels = 2;

    st->codecpar->sample_rate = s1->sample_rate;

    st->start_time = 0;

    return st;

}

static int aptx_read_header(AVFormatContext *s)

{

    AVStream *st = aptx_read_header_common(s);

    if (!st)

        return AVERROR(ENOMEM);

    st->codecpar->codec_id = AV_CODEC_ID_APTX;

    st->codecpar->bits_per_coded_sample = 4;

    st->codecpar->block_align = APTX_BLOCK_SIZE;

    return 0;

}

static int aptx_hd_read_header(AVFormatContext *s)

{

    AVStream *st = aptx_read_header_common(s);

    if (!st)

        return AVERROR(ENOMEM);

    st->codecpar->codec_id = AV_CODEC_ID_APTX_HD;

    st->codecpar->bits_per_coded_sample = 6;

    st->codecpar->block_align = APTX_HD_BLOCK_SIZE;

    return 0;

}

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

{

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

    if (ret >= 0 && !(ret % APTX_BLOCK_SIZE))

        pkt->flags &= ~AV_PKT_FLAG_CORRUPT;

    return ret >= 0 ? 0 : ret;

}

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

{

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

    if (ret >= 0 && !(ret % APTX_HD_BLOCK_SIZE))

        pkt->flags &= ~AV_PKT_FLAG_CORRUPT;

    return ret >= 0 ? 0 : ret;

}

static const AVOption aptx_options[] = {

    { "sample_rate", "", offsetof(AptXDemuxerContext, sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },

    { NULL },

};

static const AVClass aptx_demuxer_class = {

    .class_name = "aptx (hd) demuxer",

    .item_name  = av_default_item_name,

    .option     = aptx_options,

    .version    = LIBAVUTIL_VERSION_INT,

};

#if CONFIG_APTX_DEMUXER

const FFInputFormat ff_aptx_demuxer = {

    .p.name         = "aptx",

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

    .p.extensions   = "aptx",

    .p.flags        = AVFMT_GENERIC_INDEX,

    .p.priv_class   = &aptx_demuxer_class,

    .priv_data_size = sizeof(AptXDemuxerContext),

    .read_header    = aptx_read_header,

    .read_packet    = aptx_read_packet,

};

#endif

#if CONFIG_APTX_HD_DEMUXER

const FFInputFormat ff_aptx_hd_demuxer = {

    .p.name         = "aptx_hd",

    .p.long_name    = NULL_IF_CONFIG_SMALL("raw aptX HD"),

    .p.extensions   = "aptxhd",

    .p.flags        = AVFMT_GENERIC_INDEX,

    .p.priv_class   = &aptx_demuxer_class,

    .priv_data_size = sizeof(AptXDemuxerContext),

    .read_header    = aptx_hd_read_header,

    .read_packet    = aptx_hd_read_packet,

};

#endif