/*

 * AAX demuxer

 * Copyright (c) 2020 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/intreadwrite.h"

#include "libavutil/mem.h"

#include "avformat.h"

#include "avio_internal.h"

#include "demux.h"

#include "internal.h"

typedef struct AAXColumn {

    uint8_t flag;

    uint8_t type;

    const char *name;

    uint32_t offset;

    int size;

} AAXColumn;

typedef struct AAXSegment {

    int64_t start;

    int64_t end;

} AAXSegment;

typedef struct AAXContext {

    int64_t table_size;

    uint16_t version;

    int64_t rows_offset;

    int64_t strings_offset;

    int64_t data_offset;

    int64_t name_offset;

    uint16_t columns;

    uint16_t row_width;

    uint32_t nb_segments;

    int64_t schema_offset;

    int64_t strings_size;

    char *string_table;

    uint32_t current_segment;

    AAXColumn *xcolumns;

    AAXSegment *segments;

} AAXContext;

static int aax_probe(const AVProbeData *p)

{

    if (AV_RB32(p->buf) != MKBETAG('@','U','T','F'))

        return 0;

    if (AV_RB32(p->buf + 4) == 0)

        return 0;

    if (AV_RB16(p->buf + 8) > 1)

        return 0;

    if (AV_RB32(p->buf + 28) < 1)

        return 0;

    return AVPROBE_SCORE_MAX;

}

enum ColumnFlag {

    COLUMN_FLAG_NAME            = 0x1,

    COLUMN_FLAG_DEFAULT         = 0x2,

    COLUMN_FLAG_ROW             = 0x4,

    COLUMN_FLAG_UNDEFINED       = 0x8 /* shouldn't exist */

};

enum ColumnType {

    COLUMN_TYPE_UINT8           = 0x00,

    COLUMN_TYPE_SINT8           = 0x01,

    COLUMN_TYPE_UINT16          = 0x02,

    COLUMN_TYPE_SINT16          = 0x03,

    COLUMN_TYPE_UINT32          = 0x04,

    COLUMN_TYPE_SINT32          = 0x05,

    COLUMN_TYPE_UINT64          = 0x06,

    COLUMN_TYPE_SINT64          = 0x07,

    COLUMN_TYPE_FLOAT           = 0x08,

    COLUMN_TYPE_DOUBLE          = 0x09,

    COLUMN_TYPE_STRING          = 0x0a,

    COLUMN_TYPE_VLDATA          = 0x0b,

    COLUMN_TYPE_UINT128         = 0x0c, /* for GUIDs */

    COLUMN_TYPE_UNDEFINED       = -1

};

static int64_t get_pts(AVFormatContext *s, int64_t pos, int size)

{

    AAXContext *a = s->priv_data;

    int64_t pts = 0;

    for (int seg = 0; seg < a->current_segment; seg++)

        pts += (a->segments[seg].end - a->segments[seg].start) / size;

    pts += ((pos - a->segments[a->current_segment].start) / size);

    return pts;

}

static int aax_read_header(AVFormatContext *s)

{

    AAXContext *a = s->priv_data;

    AVIOContext *pb = s->pb;

    AVCodecParameters *par;

    AVStream *st;

    int64_t column_offset = 0;

    int ret, extradata_size;

    char *codec;

    int64_t ret64;

    avio_skip(pb, 4);

    a->table_size      = avio_rb32(pb) + 8LL;

    a->version         = avio_rb16(pb);

    a->rows_offset     = avio_rb16(pb) + 8LL;

    a->strings_offset  = avio_rb32(pb) + 8LL;

    a->data_offset     = avio_rb32(pb) + 8LL;

    a->name_offset     = avio_rb32(pb);

    a->columns         = avio_rb16(pb);

    a->row_width       = avio_rb16(pb);

    a->nb_segments     = avio_rb32(pb);

    if (a->nb_segments < 1)

        return AVERROR_INVALIDDATA;

    a->schema_offset   = 0x20;

    a->strings_size    = a->data_offset - a->strings_offset;

    if (a->rows_offset > a->table_size ||

        a->strings_offset > a->table_size ||

        a->data_offset > a->table_size)

        return AVERROR_INVALIDDATA;

    if (a->strings_size <= 0 || a->name_offset >= a->strings_size ||

        a->strings_size > UINT16_MAX)

        return AVERROR_INVALIDDATA;

    if (a->columns <= 0)

        return AVERROR_INVALIDDATA;

    a->segments = av_calloc(a->nb_segments, sizeof(*a->segments));

    if (!a->segments)

        return AVERROR(ENOMEM);

    a->xcolumns = av_calloc(a->columns, sizeof(*a->xcolumns));

    if (!a->xcolumns)

        return AVERROR(ENOMEM);

    a->string_table = av_calloc(a->strings_size + 1, sizeof(*a->string_table));

    if (!a->string_table)

        return AVERROR(ENOMEM);

    for (int c = 0; c < a->columns; c++) {

        uint8_t info = avio_r8(pb);

        uint32_t offset = avio_rb32(pb);

        int value_size;

        if (offset >= a->strings_size)

            return AVERROR_INVALIDDATA;

        a->xcolumns[c].flag = info >>   4;

        a->xcolumns[c].type = info & 0x0F;

        switch (a->xcolumns[c].type) {

        case COLUMN_TYPE_UINT8:

        case COLUMN_TYPE_SINT8:

            value_size = 0x01;

            break;

        case COLUMN_TYPE_UINT16:

        case COLUMN_TYPE_SINT16:

            value_size = 0x02;

            break;

        case COLUMN_TYPE_UINT32:

        case COLUMN_TYPE_SINT32:

        case COLUMN_TYPE_FLOAT:

        case COLUMN_TYPE_STRING:

            value_size = 0x04;

            break;

        case COLUMN_TYPE_VLDATA:

            value_size = 0x08;

            break;

        case COLUMN_TYPE_UINT128:

            value_size = 0x10;

            break;

        default:

            return AVERROR_INVALIDDATA;

        }

        a->xcolumns[c].size = value_size;

        if (a->xcolumns[c].flag & COLUMN_FLAG_NAME)

            a->xcolumns[c].name = a->string_table + offset;

        if (a->xcolumns[c].flag & COLUMN_FLAG_DEFAULT) {

            /* data is found relative to columns start */

            a->xcolumns[c].offset = avio_tell(pb) - a->schema_offset;

            avio_skip(pb, value_size);

        }

        if (a->xcolumns[c].flag & COLUMN_FLAG_ROW) {

            /* data is found relative to row start */

            a->xcolumns[c].offset = column_offset;

            column_offset += value_size;

        }

    }

    ret = ret64 = avio_seek(pb, a->strings_offset, SEEK_SET);

    if (ret64 < 0)

        return ret;

    ret = ffio_read_size(pb, a->string_table, a->strings_size);

    if (ret < 0)

        return ret;

    for (int c = 0; c < a->columns; c++) {

        int64_t data_offset = 0;

        int64_t col_offset;

        int flag, type;

        if (!a->xcolumns[c].name || strcmp(a->xcolumns[c].name, "data"))

            continue;

        type = a->xcolumns[c].type;

        flag = a->xcolumns[c].flag;

        col_offset = a->xcolumns[c].offset;

        for (uint64_t r = 0; r < a->nb_segments; r++) {

            if (flag & COLUMN_FLAG_DEFAULT) {

                data_offset = a->schema_offset + col_offset;

            } else if (flag & COLUMN_FLAG_ROW) {

                data_offset = a->rows_offset + r * a->row_width + col_offset;

            } else

                return AVERROR_INVALIDDATA;

            ret = ret64 = avio_seek(pb, data_offset, SEEK_SET);

            if (ret64 < 0)

                return ret;

            if (type == COLUMN_TYPE_VLDATA) {

                int64_t start, size;

                start = avio_rb32(pb);

                size  = avio_rb32(pb);

                if (!size)

                    return AVERROR_INVALIDDATA;

                a->segments[r].start = start + a->data_offset;

                a->segments[r].end   = a->segments[r].start + size;

                if (r &&

                    a->segments[r].start < a->segments[r-1].end &&

                    a->segments[r].end   > a->segments[r-1].start)

                    return AVERROR_INVALIDDATA;

            } else

                return AVERROR_INVALIDDATA;

        }

    }

    if (!a->segments[0].end)

        return AVERROR_INVALIDDATA;

    st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    st->start_time = 0;

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

    par->codec_type = AVMEDIA_TYPE_AUDIO;

    codec = a->string_table + a->name_offset;

    if (!strcmp(codec, "AAX")) {

        par->codec_id = AV_CODEC_ID_ADPCM_ADX;

        ret64 = avio_seek(pb, a->segments[0].start, SEEK_SET);

        if (ret64 < 0 || avio_rb16(pb) != 0x8000)

            return AVERROR_INVALIDDATA;

        extradata_size = avio_rb16(pb) + 4;

        if (extradata_size < 12)

            return AVERROR_INVALIDDATA;

        avio_seek(pb, -4, SEEK_CUR);

        ret = ff_get_extradata(s, par, pb, extradata_size);

        if (ret < 0)

            return ret;

        par->ch_layout.nb_channels = AV_RB8 (par->extradata + 7);

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

        if (!par->ch_layout.nb_channels || !par->sample_rate)

            return AVERROR_INVALIDDATA;

        avpriv_set_pts_info(st, 64, 32, par->sample_rate);

  /*} else if (!strcmp(codec, "HCA") ){

        par->codec_id = AV_CODEC_ID_HCA;*/

    } else {

        return AVERROR_INVALIDDATA;

    }

    return 0;

}

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

{

    AAXContext *a = s->priv_data;

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

    AVIOContext *pb = s->pb;

    const int size = 18 * par->ch_layout.nb_channels;

    int ret, extradata_size = 0;

    uint8_t *extradata = NULL;

    int skip = 0;

    if (avio_feof(pb))

        return AVERROR_EOF;

    pkt->pos = avio_tell(pb);

    for (uint32_t seg = 0; seg < a->nb_segments; seg++) {

        int64_t start = a->segments[seg].start;

        int64_t end   = a->segments[seg].end;

        if (pkt->pos >= start && pkt->pos <= end) {

            a->current_segment = seg;

            if (par->codec_id == AV_CODEC_ID_ADPCM_ADX)

                skip = (end - start) - ((end - start) / size) * size;

            break;

        }

    }

    if (pkt->pos >= a->segments[a->current_segment].end - skip) {

        if (a->current_segment + 1 == a->nb_segments)

            return AVERROR_EOF;

        a->current_segment++;

        avio_seek(pb, a->segments[a->current_segment].start, SEEK_SET);

        if (par->codec_id == AV_CODEC_ID_ADPCM_ADX) {

            if (avio_rb16(pb) != 0x8000)

                return AVERROR_INVALIDDATA;

            extradata_size = avio_rb16(pb) + 4;

            avio_seek(pb, -4, SEEK_CUR);

            if (extradata_size < 12)

                return AVERROR_INVALIDDATA;

            extradata = av_malloc(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);

            if (!extradata)

                return AVERROR(ENOMEM);

            if (avio_read(pb, extradata, extradata_size) != extradata_size) {

                av_free(extradata);

                return AVERROR(EIO);

            }

            memset(extradata + extradata_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

        }

    }

    ret = av_get_packet(pb, pkt, size);

    if (ret != size) {

        av_free(extradata);

        return ret < 0 ? ret : AVERROR(EIO);

    }

    pkt->duration = 1;

    pkt->stream_index = 0;

    pkt->pts = get_pts(s, pkt->pos, size);

    if (extradata) {

        ret = av_packet_add_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA, extradata, extradata_size);

        if (ret < 0) {

            av_free(extradata);

            return ret;

        }

    }

    return ret;

}

static int aax_read_close(AVFormatContext *s)

{

    AAXContext *a = s->priv_data;

    av_freep(&a->segments);

    av_freep(&a->xcolumns);

    av_freep(&a->string_table);

    return 0;

}

const FFInputFormat ff_aax_demuxer = {

    .p.name         = "aax",

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

    .p.extensions   = "aax",

    .p.flags        = AVFMT_GENERIC_INDEX,

    .priv_data_size = sizeof(AAXContext),

    .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,

    .read_probe     = aax_probe,

    .read_header    = aax_read_header,

    .read_packet    = aax_read_packet,

    .read_close     = aax_read_close,

};