/*

 * DXA demuxer

 * Copyright (c) 2007 Konstantin Shishkov

 *

 * 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 <inttypes.h>

#include "libavutil/intreadwrite.h"

#include "avformat.h"

#include "demux.h"

#include "internal.h"

#include "riff.h"

#define DXA_EXTRA_SIZE  9

typedef struct DXAContext {

    int frames;

    int has_sound;

    int bpc;

    uint32_t bytes_left;

    int64_t wavpos, vidpos;

    int readvid;

}DXAContext;

static int dxa_probe(const AVProbeData *p)

{

    int w, h;

    if (p->buf_size < 15)

        return 0;

    w = AV_RB16(p->buf + 11);

    h = AV_RB16(p->buf + 13);

    /* check file header */

    if (p->buf[0] == 'D' && p->buf[1] == 'E' &&

        p->buf[2] == 'X' && p->buf[3] == 'A' &&

        w && w <= 2048 && h && h <= 2048)

        return AVPROBE_SCORE_MAX;

    else

        return 0;

}

static int dxa_read_header(AVFormatContext *s)

{

    AVIOContext *pb = s->pb;

    DXAContext *c = s->priv_data;

    AVStream *st, *ast;

    uint32_t tag;

    int32_t fps;

    int w, h;

    int num, den;

    int flags;

    int ret;

    tag = avio_rl32(pb);

    if (tag != MKTAG('D', 'E', 'X', 'A'))

        return AVERROR_INVALIDDATA;

    flags = avio_r8(pb);

    c->frames = avio_rb16(pb);

    if(!c->frames){

        av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");

        return AVERROR_INVALIDDATA;

    }

    fps = avio_rb32(pb);

    if(fps > 0){

        den = 1000;

        num = fps;

    }else if (fps < 0 && fps > INT_MIN){

        den = 100000;

        num = -fps;

    }else{

        den = 10;

        num = 1;

    }

    w = avio_rb16(pb);

    h = avio_rb16(pb);

    c->has_sound = 0;

    st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    // Parse WAV data header

    if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){

        uint32_t size, fsize;

        c->has_sound = 1;

        size = avio_rb32(pb);

        c->vidpos = avio_tell(pb) + size;

        avio_skip(pb, 16);

        fsize = avio_rl32(pb);

        ast = avformat_new_stream(s, NULL);

        if (!ast)

            return AVERROR(ENOMEM);

        ret = ff_get_wav_header(s, pb, ast->codecpar, fsize, 0);

        if (ret < 0)

            return ret;

        if (ast->codecpar->sample_rate > 0)

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

        // find 'data' chunk

        while(avio_tell(pb) < c->vidpos && !avio_feof(pb)){

            tag = avio_rl32(pb);

            fsize = avio_rl32(pb);

            if(tag == MKTAG('d', 'a', 't', 'a')) break;

            avio_skip(pb, fsize);

        }

        c->bpc = (fsize + (int64_t)c->frames - 1) / c->frames;

        if(ast->codecpar->block_align) {

            if (c->bpc > INT_MAX - ast->codecpar->block_align + 1)

                return AVERROR_INVALIDDATA;

            c->bpc = ((c->bpc - 1 + ast->codecpar->block_align) / ast->codecpar->block_align) * ast->codecpar->block_align;

        }

        c->bytes_left = fsize;

        c->wavpos = avio_tell(pb);

        avio_seek(pb, c->vidpos, SEEK_SET);

    }

    /* now we are ready: build format streams */

    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;

    st->codecpar->codec_id   = AV_CODEC_ID_DXA;

    st->codecpar->width      = w;

    st->codecpar->height     = h;

    av_reduce(&den, &num, den, num, (1UL<<31)-1);

    avpriv_set_pts_info(st, 33, num, den);

    /* flags & 0x80 means that image is interlaced,

     * flags & 0x40 means that image has double height

     * either way set true height

     */

    if(flags & 0xC0){

        st->codecpar->height >>= 1;

    }

    c->readvid = !c->has_sound;

    c->vidpos  = avio_tell(pb);

    s->start_time = 0;

    s->duration = av_rescale(c->frames, AV_TIME_BASE * (int64_t)num, den);

    av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);

    return 0;

}

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

{

    DXAContext *c = s->priv_data;

    int ret;

    uint32_t size;

    uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];

    int pal_size = 0;

    if(!c->readvid && c->has_sound && c->bytes_left){

        c->readvid = 1;

        avio_seek(s->pb, c->wavpos, SEEK_SET);

        size = FFMIN(c->bytes_left, c->bpc);

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

        pkt->stream_index = 1;

        if(ret != size)

            return AVERROR(EIO);

        c->bytes_left -= size;

        c->wavpos = avio_tell(s->pb);

        return 0;

    }

    avio_seek(s->pb, c->vidpos, SEEK_SET);

    while(!avio_feof(s->pb) && c->frames){

        uint32_t tag;

        if ((ret = avio_read(s->pb, buf, 4)) != 4) {

            av_log(s, AV_LOG_ERROR, "failed reading chunk type\n");

            return ret < 0 ? ret : AVERROR_INVALIDDATA;

        }

        tag = AV_RL32(buf);

        switch (tag) {

        case MKTAG('N', 'U', 'L', 'L'):

            if ((ret = av_new_packet(pkt, 4 + pal_size)) < 0)

                return ret;

            pkt->stream_index = 0;

            if(pal_size) memcpy(pkt->data, pal, pal_size);

            memcpy(pkt->data + pal_size, buf, 4);

            c->frames--;

            c->vidpos = avio_tell(s->pb);

            c->readvid = 0;

            return 0;

        case MKTAG('C', 'M', 'A', 'P'):

            pal_size = 768+4;

            memcpy(pal, buf, 4);

            avio_read(s->pb, pal + 4, 768);

            break;

        case MKTAG('F', 'R', 'A', 'M'):

            if ((ret = avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4)) != DXA_EXTRA_SIZE - 4) {

                av_log(s, AV_LOG_ERROR, "failed reading dxa_extra\n");

                return ret < 0 ? ret : AVERROR_INVALIDDATA;

            }

            size = AV_RB32(buf + 5);

            if(size > 0xFFFFFF){

                av_log(s, AV_LOG_ERROR, "Frame size is too big: %"PRIu32"\n",

                       size);

                return AVERROR_INVALIDDATA;

            }

            ret = av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size);

            if (ret < 0)

                return ret;

            memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);

            ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);

            if(ret != size){

                return AVERROR(EIO);

            }

            if(pal_size) memcpy(pkt->data, pal, pal_size);

            pkt->stream_index = 0;

            c->frames--;

            c->vidpos = avio_tell(s->pb);

            c->readvid = 0;

            return 0;

        default:

            av_log(s, AV_LOG_ERROR, "Unknown tag %s\n", av_fourcc2str(tag));

            return AVERROR_INVALIDDATA;

        }

    }

    return AVERROR_EOF;

}

const FFInputFormat ff_dxa_demuxer = {

    .p.name         = "dxa",

    .p.long_name    = NULL_IF_CONFIG_SMALL("DXA"),

    .priv_data_size = sizeof(DXAContext),

    .read_probe     = dxa_probe,

    .read_header    = dxa_read_header,

    .read_packet    = dxa_read_packet,

};