/*

 * Copyright (c) 2011 Justin Ruggles

 *

 * 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

 */

/**

 * @file

 * CRI ADX demuxer

 */

#include "libavutil/intreadwrite.h"

#include "avformat.h"

#include "demux.h"

#include "internal.h"

#include "rawdec.h"

#define BLOCK_SIZE    18

#define BLOCK_SAMPLES 32

typedef struct ADXDemuxerContext {

    FFRawDemuxerContext rawctx;

    int header_size;

} ADXDemuxerContext;

static int adx_probe(const AVProbeData *p)

{

    int offset;

    if (AV_RB16(p->buf) != 0x8000)

        return 0;

    offset = AV_RB16(&p->buf[2]);

    if (   offset < 8

        || offset > p->buf_size - 4

        || memcmp(p->buf + offset - 2, "(c)CRI", 6))

        return 0;

    return AVPROBE_SCORE_MAX * 3 / 4;

}

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

{

    ADXDemuxerContext *c = s->priv_data;

    AVCodecParameters *par = s->streams[0]->codecpar;

    int ret, size;

    if (par->codec_id == AV_CODEC_ID_AHX)

        return ff_raw_read_partial_packet(s, pkt);

    if (avio_feof(s->pb))

        return AVERROR_EOF;

    size = BLOCK_SIZE * par->ch_layout.nb_channels;

    pkt->pos = avio_tell(s->pb);

    pkt->stream_index = 0;

    ret = av_get_packet(s->pb, pkt, size * 128);

    if (ret < 0)

        return ret;

    if ((ret % size) && ret >= size) {

        size = ret - (ret % size);

        av_shrink_packet(pkt, size);

        pkt->flags &= ~AV_PKT_FLAG_CORRUPT;

    } else if (ret < size) {

        return AVERROR_INVALIDDATA;

    } else {

        size = ret;

    }

    pkt->duration = size / (BLOCK_SIZE * par->ch_layout.nb_channels);

    pkt->pts      = (pkt->pos - c->header_size) / (BLOCK_SIZE * par->ch_layout.nb_channels);

    return 0;

}

static int adx_read_header(AVFormatContext *s)

{

    ADXDemuxerContext *c = s->priv_data;

    AVCodecParameters *par;

    FFStream *sti;

    int ret;

    int channels;

    AVStream *st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    par = s->streams[0]->codecpar;

    if (avio_rb16(s->pb) != 0x8000)

        return AVERROR_INVALIDDATA;

    c->header_size = avio_rb16(s->pb) + 4;

    avio_seek(s->pb, -4, SEEK_CUR);

    if ((ret = ff_get_extradata(s, par, s->pb, c->header_size)) < 0)

        return ret;

    if (par->extradata_size < 12) {

        av_log(s, AV_LOG_ERROR, "Invalid extradata size.\n");

        return AVERROR_INVALIDDATA;

    }

    channels = AV_RB8 (par->extradata + 7);

    par->sample_rate = AV_RB32(par->extradata + 8);

    if (channels <= 0) {

        av_log(s, AV_LOG_ERROR, "invalid number of channels %d\n", channels);

        return AVERROR_INVALIDDATA;

    }

    if (par->sample_rate <= 0) {

        av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", par->sample_rate);

        return AVERROR_INVALIDDATA;

    }

    sti = ffstream(st);

    par->ch_layout.nb_channels = channels;

    par->codec_type  = AVMEDIA_TYPE_AUDIO;

    switch (par->extradata[4]) {

    case 3:

        sti->need_parsing = AVSTREAM_PARSE_FULL_RAW;

        par->codec_id = AV_CODEC_ID_ADPCM_ADX;

        par->bit_rate    = (int64_t)par->sample_rate * par->ch_layout.nb_channels * BLOCK_SIZE * 8LL / BLOCK_SAMPLES;

        avpriv_set_pts_info(st, 64, BLOCK_SAMPLES, par->sample_rate);

        break;

    case 16:

        sti->need_parsing = AVSTREAM_PARSE_FULL_RAW;

        par->codec_id = AV_CODEC_ID_AHX;

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

        break;

    default:

        av_log(s, AV_LOG_ERROR, "Unsupported format: %d\n", par->extradata[4]);

        return AVERROR_INVALIDDATA;

    }

    return 0;

}

const FFInputFormat ff_adx_demuxer = {

    .p.name         = "adx",

    .p.long_name    = NULL_IF_CONFIG_SMALL("CRI ADX"),

    .p.extensions   = "adx",

    .p.priv_class   = &ff_raw_demuxer_class,

    .p.flags        = AVFMT_GENERIC_INDEX,

    .read_probe     = adx_probe,

    .priv_data_size = sizeof(ADXDemuxerContext),

    .read_header    = adx_read_header,

    .read_packet    = adx_read_packet,

};