/*

 * VQF demuxer

 * Copyright (c) 2009 Vitor Sessak

 *

 * 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 "avformat.h"

#include "avio_internal.h"

#include "demux.h"

#include "internal.h"

#include "libavutil/intreadwrite.h"

#include "libavutil/dict.h"

#include "libavutil/mathematics.h"

#include "libavutil/mem.h"

#include "metadata.h"

typedef struct VqfContext {

    int frame_bit_len;

    uint8_t last_frame_bits;

    int remaining_bits;

} VqfContext;

static int vqf_probe(const AVProbeData *probe_packet)

{

    if (AV_RL32(probe_packet->buf) != MKTAG('T','W','I','N'))

        return 0;

    if (!memcmp(probe_packet->buf + 4, "97012000", 8))

        return AVPROBE_SCORE_MAX;

    if (!memcmp(probe_packet->buf + 4, "00052200", 8))

        return AVPROBE_SCORE_MAX;

    if (AV_RL32(probe_packet->buf + 12) > (1<<27))

        return AVPROBE_SCORE_EXTENSION/2;

    return AVPROBE_SCORE_EXTENSION;

}

static int add_metadata(AVFormatContext *s, uint32_t tag,

                         unsigned int tag_len, unsigned int remaining)

{

    int len = FFMIN(tag_len, remaining);

    char *buf, key[5] = {0};

    int ret;

    if (len == UINT_MAX)

        return AVERROR_INVALIDDATA;

    buf = av_malloc(len+1);

    if (!buf)

        return AVERROR(ENOMEM);

    ret = ffio_read_size(s->pb, buf, len);

    if (ret < 0) {

        av_free(buf);

        return ret;

    }

    buf[len] = 0;

    AV_WL32(key, tag);

    return av_dict_set(&s->metadata, key, buf, AV_DICT_DONT_STRDUP_VAL);

}

static const AVMetadataConv vqf_metadata_conv[] = {

    { "(c) ", "copyright" },

    { "ARNG", "arranger"  },

    { "AUTH", "author"    },

    { "BAND", "band"      },

    { "CDCT", "conductor" },

    { "COMT", "comment"   },

    { "FILE", "filename"  },

    { "GENR", "genre"     },

    { "LABL", "publisher" },

    { "MUSC", "composer"  },

    { "NAME", "title"     },

    { "NOTE", "note"      },

    { "PROD", "producer"  },

    { "PRSN", "personnel" },

    { "REMX", "remixer"   },

    { "SING", "singer"    },

    { "TRCK", "track"     },

    { "WORD", "words"     },

    { 0 },

};

static int vqf_read_header(AVFormatContext *s)

{

    VqfContext *c = s->priv_data;

    AVStream *st  = avformat_new_stream(s, NULL);

    int chunk_tag;

    int rate_flag = -1;

    int header_size;

    int read_bitrate = 0;

    int size, ret;

    uint8_t comm_chunk[12];

    if (!st)

        return AVERROR(ENOMEM);

    avio_skip(s->pb, 12);

    header_size = avio_rb32(s->pb);

    if (header_size < 0)

        return AVERROR_INVALIDDATA;

    st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;

    st->codecpar->codec_id   = AV_CODEC_ID_TWINVQ;

    st->start_time = 0;

    do {

        int len;

        chunk_tag = avio_rl32(s->pb);

        if (chunk_tag == MKTAG('D','A','T','A'))

            break;

        len = avio_rb32(s->pb);

        if ((unsigned) len > INT_MAX/2 || header_size < 8) {

            av_log(s, AV_LOG_ERROR, "Malformed header\n");

            return -1;

        }

        header_size -= 8;

        switch(chunk_tag){

        case MKTAG('C','O','M','M'):

            if (len < 12)

                return AVERROR_INVALIDDATA;

            ret = ffio_read_size(s->pb, comm_chunk, 12);

            if (ret < 0)

                return ret;

            st->codecpar->ch_layout.nb_channels = AV_RB32(comm_chunk) + 1;

            read_bitrate        = AV_RB32(comm_chunk + 4);

            rate_flag           = AV_RB32(comm_chunk + 8);

            avio_skip(s->pb, len-12);

            if (st->codecpar->ch_layout.nb_channels <= 0) {

                av_log(s, AV_LOG_ERROR, "Invalid number of channels\n");

                return AVERROR_INVALIDDATA;

            }

            st->codecpar->bit_rate = (int64_t)read_bitrate * 1000;

            break;

        case MKTAG('D','S','I','Z'): // size of compressed data

        {

            av_dict_set_int(&s->metadata, "size", avio_rb32(s->pb), 0);

        }

            break;

        case MKTAG('Y','E','A','R'): // recording date

        case MKTAG('E','N','C','D'): // compression date

        case MKTAG('E','X','T','R'): // reserved

        case MKTAG('_','Y','M','H'): // reserved

        case MKTAG('_','N','T','T'): // reserved

        case MKTAG('_','I','D','3'): // reserved for ID3 tags

            avio_skip(s->pb, FFMIN(len, header_size));

            break;

        default:

            ret = add_metadata(s, chunk_tag, len, header_size);

            if (ret < 0)

                return ret;

            break;

        }

        header_size -= len;

    } while (header_size >= 0 && !avio_feof(s->pb));

    switch (rate_flag) {

    case -1:

        av_log(s, AV_LOG_ERROR, "COMM tag not found!\n");

        return -1;

    case 44:

        st->codecpar->sample_rate = 44100;

        break;

    case 22:

        st->codecpar->sample_rate = 22050;

        break;

    case 11:

        st->codecpar->sample_rate = 11025;

        break;

    default:

        if (rate_flag < 8 || rate_flag > 44) {

            av_log(s, AV_LOG_ERROR, "Invalid rate flag %d\n", rate_flag);

            return AVERROR_INVALIDDATA;

        }

        st->codecpar->sample_rate = rate_flag*1000;

        break;

    }

    if (read_bitrate / st->codecpar->ch_layout.nb_channels <  8 ||

        read_bitrate / st->codecpar->ch_layout.nb_channels > 48) {

        av_log(s, AV_LOG_ERROR, "Invalid bitrate per channel %d\n",

               read_bitrate / st->codecpar->ch_layout.nb_channels);

        return AVERROR_INVALIDDATA;

    }

    switch (((st->codecpar->sample_rate/1000) << 8) +

            read_bitrate/st->codecpar->ch_layout.nb_channels) {

    case (11<<8) + 8 :

    case (8 <<8) + 8 :

    case (11<<8) + 10:

    case (22<<8) + 32:

        size = 512;

        break;

    case (16<<8) + 16:

    case (22<<8) + 20:

    case (22<<8) + 24:

        size = 1024;

        break;

    case (44<<8) + 40:

    case (44<<8) + 48:

        size = 2048;

        break;

    default:

        av_log(s, AV_LOG_ERROR, "Mode not supported: %d Hz, %"PRId64" kb/s.\n",

               st->codecpar->sample_rate, st->codecpar->bit_rate);

        return -1;

    }

    c->frame_bit_len = st->codecpar->bit_rate*size/st->codecpar->sample_rate;

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

    /* put first 12 bytes of COMM chunk in extradata */

    if ((ret = ff_alloc_extradata(st->codecpar, 12)) < 0)

        return ret;

    memcpy(st->codecpar->extradata, comm_chunk, 12);

    ff_metadata_conv_ctx(s, NULL, vqf_metadata_conv);

    return 0;

}

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

{

    VqfContext *c = s->priv_data;

    int ret;

    int size = (c->frame_bit_len - c->remaining_bits + 7)>>3;

    if ((ret = av_new_packet(pkt, size + 2)) < 0)

        return ret;

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

    pkt->stream_index = 0;

    pkt->duration     = 1;

    pkt->data[0] = 8 - c->remaining_bits; // Number of bits to skip

    pkt->data[1] = c->last_frame_bits;

    ret = ffio_read_size(s->pb, pkt->data + 2, size);

    if (ret < 0)

        return ret;

    c->last_frame_bits = pkt->data[size+1];

    c->remaining_bits  = (size << 3) - c->frame_bit_len + c->remaining_bits;

    return 0;

}

static int vqf_read_seek(AVFormatContext *s,

                         int stream_index, int64_t timestamp, int flags)

{

    VqfContext *c = s->priv_data;

    AVStream *st;

    int64_t ret;

    int64_t pos;

    st = s->streams[stream_index];

    pos = av_rescale_rnd(timestamp * st->codecpar->bit_rate,

                         st->time_base.num,

                         st->time_base.den * (int64_t)c->frame_bit_len,

                         (flags & AVSEEK_FLAG_BACKWARD) ?

                                                   AV_ROUND_DOWN : AV_ROUND_UP);

    pos *= c->frame_bit_len;

    ffstream(st)->cur_dts = av_rescale(pos, st->time_base.den,

                             st->codecpar->bit_rate * (int64_t)st->time_base.num);

    if ((ret = avio_seek(s->pb, ((pos-7) >> 3) + ffformatcontext(s)->data_offset, SEEK_SET)) < 0)

        return ret;

    c->remaining_bits = -7 - ((pos-7)&7);

    return 0;

}

const FFInputFormat ff_vqf_demuxer = {

    .p.name         = "vqf",

    .p.long_name    = NULL_IF_CONFIG_SMALL("Nippon Telegraph and Telephone Corporation (NTT) TwinVQ"),

    .p.extensions   = "vqf,vql,vqe",

    .priv_data_size = sizeof(VqfContext),

    .read_probe     = vqf_probe,

    .read_header    = vqf_read_header,

    .read_packet    = vqf_read_packet,

    .read_seek      = vqf_read_seek,

};