/*

 * Smacker demuxer

 * Copyright (c) 2006 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

 */

/*

 * Based on http://wiki.multimedia.cx/index.php?title=Smacker

 */

#include <inttypes.h>

#include "libavutil/channel_layout.h"

#include "libavutil/intreadwrite.h"

#include "libavutil/mem.h"

#include "avformat.h"

#include "avio_internal.h"

#include "demux.h"

#include "internal.h"

#define SMACKER_PAL 0x01

#define SMACKER_FLAG_RING_FRAME 0x01

#define SMACKER_FLAG_Y_INTERLACE (1 << 1)

#define SMACKER_FLAG_Y_DOUBLE    (1 << 2)

enum SAudFlags {

    SMK_AUD_PACKED  = 0x80,

    SMK_AUD_16BITS  = 0x20,

    SMK_AUD_STEREO  = 0x10,

    SMK_AUD_BINKAUD = 0x08,

    SMK_AUD_USEDCT  = 0x04

};

typedef struct SmackerContext {

    uint32_t frames;

    /* frame info */

    uint32_t *frm_size;

    uint8_t  *frm_flags;

    /* internal variables */

    int64_t next_frame_pos;

    int cur_frame;

    int videoindex;

    int indexes[7];

    int duration_size[7];

    /* current frame for demuxing */

    uint32_t frame_size;

    int flags;

    int next_audio_index;

    int new_palette;

    uint8_t pal[768];

    int64_t aud_pts[7];

} SmackerContext;

/* palette used in Smacker */

static const uint8_t smk_pal[64] = {

    0x00, 0x04, 0x08, 0x0C, 0x10, 0x14, 0x18, 0x1C,

    0x20, 0x24, 0x28, 0x2C, 0x30, 0x34, 0x38, 0x3C,

    0x41, 0x45, 0x49, 0x4D, 0x51, 0x55, 0x59, 0x5D,

    0x61, 0x65, 0x69, 0x6D, 0x71, 0x75, 0x79, 0x7D,

    0x82, 0x86, 0x8A, 0x8E, 0x92, 0x96, 0x9A, 0x9E,

    0xA2, 0xA6, 0xAA, 0xAE, 0xB2, 0xB6, 0xBA, 0xBE,

    0xC3, 0xC7, 0xCB, 0xCF, 0xD3, 0xD7, 0xDB, 0xDF,

    0xE3, 0xE7, 0xEB, 0xEF, 0xF3, 0xF7, 0xFB, 0xFF

};

static int smacker_probe(const AVProbeData *p)

{

    if (   AV_RL32(p->buf) != MKTAG('S', 'M', 'K', '2')

        && AV_RL32(p->buf) != MKTAG('S', 'M', 'K', '4'))

        return 0;

    if (AV_RL32(p->buf+4) > 32768U || AV_RL32(p->buf+8) > 32768U)

        return AVPROBE_SCORE_MAX/4;

    return AVPROBE_SCORE_MAX;

}

static int smacker_read_header(AVFormatContext *s)

{

    AVIOContext *pb = s->pb;

    SmackerContext *smk = s->priv_data;

    AVStream *st;

    AVCodecParameters *par;

    uint32_t magic, width, height, flags, treesize;

    int64_t pos;

    int i, ret, pts_inc;

    int tbase;

    /* read and check header */

    magic  = avio_rl32(pb);

    if (magic != MKTAG('S', 'M', 'K', '2') && magic != MKTAG('S', 'M', 'K', '4'))

        return AVERROR_INVALIDDATA;

    width  = avio_rl32(pb);

    height = avio_rl32(pb);

    smk->frames = avio_rl32(pb);

    pts_inc = avio_rl32(pb);

    if (pts_inc > INT_MAX / 100 || pts_inc == INT_MIN) {

        av_log(s, AV_LOG_ERROR, "pts_inc %d is invalid\n", pts_inc);

        return AVERROR_INVALIDDATA;

    }

    flags = avio_rl32(pb);

    if (flags & SMACKER_FLAG_RING_FRAME)

        smk->frames++;

    if (smk->frames > 0xFFFFFF) {

        av_log(s, AV_LOG_ERROR, "Too many frames: %"PRIu32"\n", smk->frames);

        return AVERROR_INVALIDDATA;

    }

    avio_skip(pb, 28); /* Unused audio related data */

    treesize = avio_rl32(pb);

    if (treesize >= UINT_MAX/4) {

        // treesize + 16 must not overflow (this check is probably redundant)

        av_log(s, AV_LOG_ERROR, "treesize too large\n");

        return AVERROR_INVALIDDATA;

    }

    st = avformat_new_stream(s, NULL);

    if (!st)

        return AVERROR(ENOMEM);

    smk->videoindex = st->index;

    /* Smacker uses 100000 as internal timebase */

    if (pts_inc < 0)

        pts_inc = -pts_inc;

    else

        pts_inc *= 100;

    tbase = 100000;

    av_reduce(&tbase, &pts_inc, tbase, pts_inc, (1UL << 31) - 1);

    avpriv_set_pts_info(st, 33, pts_inc, tbase);

    st->duration = smk->frames;

    st->sample_aspect_ratio = (AVRational){ 1, 1 +

        !!(flags & (SMACKER_FLAG_Y_INTERLACE | SMACKER_FLAG_Y_DOUBLE)) };

    /* init video codec */

    par = st->codecpar;

    par->width      = width;

    par->height     = height;

    par->format     = AV_PIX_FMT_PAL8;

    par->codec_type = AVMEDIA_TYPE_VIDEO;

    par->codec_id   = AV_CODEC_ID_SMACKVIDEO;

    par->codec_tag  = magic;

    if ((ret = ff_alloc_extradata(par, treesize + 16)) < 0) {

        av_log(s, AV_LOG_ERROR,

               "Cannot allocate %"PRIu32" bytes of extradata\n",

               treesize + 16);

        return ret;

    }

    if ((ret = ffio_read_size(pb, par->extradata, 16)) < 0)

        return ret;

    /* handle possible audio streams */

    for (i = 0; i < 7; i++) {

        uint32_t rate = avio_rl24(pb);

        uint8_t aflag = avio_r8(pb);

        smk->indexes[i] = -1;

        if (rate) {

            AVStream *ast = avformat_new_stream(s, NULL);

            AVCodecParameters *par;

            if (!ast)

                return AVERROR(ENOMEM);

            smk->indexes[i] = ast->index;

            par = ast->codecpar;

            par->codec_type = AVMEDIA_TYPE_AUDIO;

            if (aflag & SMK_AUD_BINKAUD) {

                par->codec_id  = AV_CODEC_ID_BINKAUDIO_RDFT;

            } else if (aflag & SMK_AUD_USEDCT) {

                par->codec_id  = AV_CODEC_ID_BINKAUDIO_DCT;

            } else if (aflag & SMK_AUD_PACKED) {

                par->codec_id  = AV_CODEC_ID_SMACKAUDIO;

                par->codec_tag = MKTAG('S', 'M', 'K', 'A');

            } else {

                par->codec_id  = AV_CODEC_ID_PCM_U8;

            }

            av_channel_layout_default(&par->ch_layout,

                                      !!(aflag & SMK_AUD_STEREO) + 1);

            par->sample_rate = rate;

            par->bits_per_coded_sample = (aflag & SMK_AUD_16BITS) ? 16 : 8;

            if (par->bits_per_coded_sample == 16 &&

                par->codec_id == AV_CODEC_ID_PCM_U8)

                par->codec_id = AV_CODEC_ID_PCM_S16LE;

            else

                smk->duration_size[i] = 4;

            avpriv_set_pts_info(ast, 64, 1, par->sample_rate * par->ch_layout.nb_channels

                                            * par->bits_per_coded_sample / 8);

        }

    }

    avio_rl32(pb); /* padding */

    /* setup data */

    st->priv_data  = av_malloc_array(smk->frames, sizeof(*smk->frm_size) +

                                                  sizeof(*smk->frm_flags));

    if (!st->priv_data)

        return AVERROR(ENOMEM);

    smk->frm_size  = st->priv_data;

    smk->frm_flags = (void*)(smk->frm_size + smk->frames);

    /* read frame info */

    pos = 0;

    for (i = 0; i < smk->frames; i++) {

        smk->frm_size[i] = avio_rl32(pb);

        if ((ret = av_add_index_entry(st, pos, i, smk->frm_size[i], 0,

                                      (i == 0 || (smk->frm_size[i] & 1)) ? AVINDEX_KEYFRAME : 0)) < 0)

            return ret;

        pos += smk->frm_size[i];

    }

    if ((ret = ffio_read_size(pb, smk->frm_flags, smk->frames)) < 0 ||

        /* load trees to extradata, they will be unpacked by decoder */

        (ret = ffio_read_size(pb, par->extradata + 16,

                              par->extradata_size - 16)) < 0) {

        return ret;

    }

    return 0;

}

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

{

    SmackerContext *smk = s->priv_data;

    int flags;

    int ret;

    if (avio_feof(s->pb) || smk->cur_frame >= smk->frames)

        return AVERROR_EOF;

    /* if we demuxed all streams, pass another frame */

    if (!smk->next_audio_index) {

        smk->frame_size = smk->frm_size[smk->cur_frame] & (~3);

        smk->next_frame_pos = avio_tell(s->pb) + smk->frame_size;

        flags = smk->frm_flags[smk->cur_frame];

        smk->flags = flags >> 1;

        /* handle palette change event */

        if (flags & SMACKER_PAL) {

            int size, sz, t, off, j, pos;

            uint8_t *pal = smk->pal;

            uint8_t oldpal[768];

            memcpy(oldpal, pal, 768);

            size = avio_r8(s->pb);

            size = size * 4;

            if (size > smk->frame_size) {

                ret = AVERROR_INVALIDDATA;

                goto next_frame;

            }

            smk->frame_size -= size--;

            sz = 0;

            pos = avio_tell(s->pb) + size;

            while (sz < 256) {

                t = avio_r8(s->pb);

                if (t & 0x80) { /* skip palette entries */

                    sz  +=  (t & 0x7F) + 1;

                    pal += ((t & 0x7F) + 1) * 3;

                } else if (t & 0x40) { /* copy with offset */

                    off = avio_r8(s->pb);

                    j = (t & 0x3F) + 1;

                    if (off + j > 0x100) {

                        av_log(s, AV_LOG_ERROR,

                               "Invalid palette update, offset=%d length=%d extends beyond palette size\n",

                               off, j);

                        ret = AVERROR_INVALIDDATA;

                        goto next_frame;

                    }

                    off *= 3;

                    while (j-- && sz < 256) {

                        *pal++ = oldpal[off + 0];

                        *pal++ = oldpal[off + 1];

                        *pal++ = oldpal[off + 2];

                        sz++;

                        off += 3;

                    }

                } else { /* new entries */

                    *pal++ = smk_pal[t];

                    *pal++ = smk_pal[avio_r8(s->pb) & 0x3F];

                    *pal++ = smk_pal[avio_r8(s->pb) & 0x3F];

                    sz++;

                }

            }

            avio_seek(s->pb, pos, 0);

            smk->new_palette = 1;

        }

    }

    for (int i = smk->next_audio_index; i < 7; i++) {

        if (smk->flags & (1 << i)) {

            uint32_t size;

            size = avio_rl32(s->pb);

            if ((int)size < 4 + smk->duration_size[i] || size > smk->frame_size) {

                av_log(s, AV_LOG_ERROR, "Invalid audio part size\n");

                ret = AVERROR_INVALIDDATA;

                goto next_frame;

            }

            smk->frame_size -= size;

            size            -= 4;

            if (smk->indexes[i] < 0 ||

                s->streams[smk->indexes[i]]->discard >= AVDISCARD_ALL) {

                smk->aud_pts[i] += smk->duration_size[i] ? avio_rl32(s->pb)

                                                         : size;

                avio_skip(s->pb, size - smk->duration_size[i]);

                continue;

            }

            if ((ret = av_get_packet(s->pb, pkt, size)) != size) {

                ret = ret < 0 ? ret : AVERROR_INVALIDDATA;

                goto next_frame;

            }

            pkt->stream_index = smk->indexes[i];

            pkt->pts          = smk->aud_pts[i];

            pkt->duration     = smk->duration_size[i] ? AV_RL32(pkt->data)

                                                      : size;

            smk->aud_pts[i]  += pkt->duration;

            smk->next_audio_index = i + 1;

            return 0;

        }

    }

    if (s->streams[smk->videoindex]->discard >= AVDISCARD_ALL) {

        ret = FFERROR_REDO;

        goto next_frame;

    }

    if (smk->frame_size >= INT_MAX/2) {

        ret = AVERROR_INVALIDDATA;

        goto next_frame;

    }

    if ((ret = av_new_packet(pkt, smk->frame_size + 769)) < 0)

        goto next_frame;

    flags = smk->new_palette;

    if ((smk->frm_size[smk->cur_frame] & 1) || smk->cur_frame == 0)

        flags |= 2;

    pkt->data[0] = flags;

    memcpy(pkt->data + 1, smk->pal, 768);

    ret = ffio_read_size(s->pb, pkt->data + 769, smk->frame_size);

    if (ret < 0)

        goto next_frame;

    pkt->stream_index = smk->videoindex;

    pkt->pts          = smk->cur_frame;

    pkt->duration = 1;

    if (flags & 2)

        pkt->flags |= AV_PKT_FLAG_KEY;

    smk->next_audio_index = 0;

    smk->new_palette = 0;

    smk->cur_frame++;

    return 0;

next_frame:

    avio_seek(s->pb, smk->next_frame_pos, SEEK_SET);

    smk->next_audio_index = 0;

    smk->cur_frame++;

    return ret;

}

static int smacker_read_seek(AVFormatContext *s, int stream_index,

                             int64_t timestamp, int flags)

{

    AVStream *st = s->streams[stream_index];

    SmackerContext *smk = s->priv_data;

    int64_t pos;

    int ret;

    if (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL))

        return -1;

    if (timestamp < 0 || timestamp >= smk->frames)

        return AVERROR(EINVAL);

    ret = av_index_search_timestamp(st, timestamp, flags);

    if (ret < 0)

        return ret;

    pos  = ffformatcontext(s)->data_offset;

    pos += ffstream(st)->index_entries[ret].pos;

    pos  = avio_seek(s->pb, pos, SEEK_SET);

    if (pos < 0)

        return pos;

    smk->cur_frame = ret;

    smk->next_audio_index = 0;

    smk->new_palette = 0;

    memset(smk->pal, 0, sizeof(smk->pal));

    memset(smk->aud_pts, 0, sizeof(smk->aud_pts));

    return 0;

}

const FFInputFormat ff_smacker_demuxer = {

    .p.name         = "smk",

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

    .priv_data_size = sizeof(SmackerContext),

    .read_probe     = smacker_probe,

    .read_header    = smacker_read_header,

    .read_packet    = smacker_read_packet,

    .read_seek      = smacker_read_seek,

};