/*

 * Bitmap Brothers JV video decoder

 * Copyright (c) 2011 Peter Ross <pross@xvid.org>

 *

 * 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

 * Bitmap Brothers JV video decoder

 * @author Peter Ross <pross@xvid.org>

 */

#include "libavutil/intreadwrite.h"

#include "avcodec.h"

#include "blockdsp.h"

#include "codec_internal.h"

#include "decode.h"

#include "get_bits.h"

typedef struct JvContext {

    BlockDSPContext bdsp;

    AVFrame   *frame;

    uint32_t   palette[AVPALETTE_COUNT];

} JvContext;

static av_cold int decode_init(AVCodecContext *avctx)

{

    JvContext *s = avctx->priv_data;

    if (!avctx->width || !avctx->height ||

        (avctx->width & 7) || (avctx->height & 7)) {

        av_log(avctx, AV_LOG_ERROR, "Invalid video dimensions: %dx%d\n",

               avctx->width, avctx->height);

        return AVERROR(EINVAL);

    }

    s->frame = av_frame_alloc();

    if (!s->frame)

        return AVERROR(ENOMEM);

    avctx->pix_fmt = AV_PIX_FMT_PAL8;

    ff_blockdsp_init(&s->bdsp);

    return 0;

}

/**

 * Decode 2x2 block

 */

static inline void decode2x2(GetBitContext *gb, uint8_t *dst, int linesize)

{

    int i, j, v[2];

    switch (get_bits(gb, 2)) {

    case 1:

        v[0] = get_bits(gb, 8);

        for (j = 0; j < 2; j++)

            memset(dst + j * linesize, v[0], 2);

        break;

    case 2:

        v[0] = get_bits(gb, 8);

        v[1] = get_bits(gb, 8);

        for (j = 0; j < 2; j++)

            for (i = 0; i < 2; i++)

                dst[j * linesize + i] = v[get_bits1(gb)];

        break;

    case 3:

        for (j = 0; j < 2; j++)

            for (i = 0; i < 2; i++)

                dst[j * linesize + i] = get_bits(gb, 8);

    }

}

/**

 * Decode 4x4 block

 */

static inline void decode4x4(GetBitContext *gb, uint8_t *dst, int linesize)

{

    int i, j, v[2];

    switch (get_bits(gb, 2)) {

    case 1:

        v[0] = get_bits(gb, 8);

        for (j = 0; j < 4; j++)

            memset(dst + j * linesize, v[0], 4);

        break;

    case 2:

        v[0] = get_bits(gb, 8);

        v[1] = get_bits(gb, 8);

        for (j = 2; j >= 0; j -= 2) {

            for (i = 0; i < 4; i++)

                dst[j * linesize + i] = v[get_bits1(gb)];

            for (i = 0; i < 4; i++)

                dst[(j + 1) * linesize + i] = v[get_bits1(gb)];

        }

        break;

    case 3:

        for (j = 0; j < 4; j += 2)

            for (i = 0; i < 4; i += 2)

                decode2x2(gb, dst + j * linesize + i, linesize);

    }

}

/**

 * Decode 8x8 block

 */

static inline void decode8x8(GetBitContext *gb, uint8_t *dst, int linesize,

                             BlockDSPContext *bdsp)

{

    int i, j, v[2];

    switch (get_bits(gb, 2)) {

    case 1:

        v[0] = get_bits(gb, 8);

        bdsp->fill_block_tab[1](dst, v[0], linesize, 8);

        break;

    case 2:

        v[0] = get_bits(gb, 8);

        v[1] = get_bits(gb, 8);

        for (j = 7; j >= 0; j--)

            for (i = 0; i < 8; i++)

                dst[j * linesize + i] = v[get_bits1(gb)];

        break;

    case 3:

        for (j = 0; j < 8; j += 4)

            for (i = 0; i < 8; i += 4)

                decode4x4(gb, dst + j * linesize + i, linesize);

    }

}

static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,

                        int *got_frame, AVPacket *avpkt)

{

    JvContext *s = avctx->priv_data;

    const uint8_t *buf = avpkt->data;

    const uint8_t *buf_end = buf + avpkt->size;

    int video_size, video_type, i, j, ret;

    if (avpkt->size < 6)

        return AVERROR_INVALIDDATA;

    video_size = AV_RL32(buf);

    video_type = buf[4];

    buf += 5;

    if (video_size) {

        if (video_size < 0 || video_size > avpkt->size - 5) {

            av_log(avctx, AV_LOG_ERROR, "video size %d invalid\n", video_size);

            return AVERROR_INVALIDDATA;

        }

        if (video_type == 0 || video_type == 1) {

            GetBitContext gb;

            init_get_bits(&gb, buf, 8 * video_size);

            if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)

                return ret;

            if (avctx->height/8 * (avctx->width/8) > 4 * video_size) {

                av_log(avctx, AV_LOG_ERROR, "Insufficient input data for dimensions\n");

                return AVERROR_INVALIDDATA;

            }

            for (j = 0; j < avctx->height; j += 8)

                for (i = 0; i < avctx->width; i += 8)

                    decode8x8(&gb,

                              s->frame->data[0] + j * s->frame->linesize[0] + i,

                              s->frame->linesize[0], &s->bdsp);

            buf += video_size;

        } else if (video_type == 2) {

            int v = *buf++;

            av_frame_unref(s->frame);

            if ((ret = ff_get_buffer(avctx, s->frame, AV_GET_BUFFER_FLAG_REF)) < 0)

                return ret;

            for (j = 0; j < avctx->height; j++)

                memset(s->frame->data[0] + j * s->frame->linesize[0],

                       v, avctx->width);

        } else {

            av_log(avctx, AV_LOG_WARNING,

                   "unsupported frame type %i\n", video_type);

            return AVERROR_INVALIDDATA;

        }

    }

    if (buf_end - buf >= AVPALETTE_COUNT * 3) {

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

            uint32_t pal = AV_RB24(buf);

            s->palette[i] = 0xFFU << 24 | pal << 2 | ((pal >> 4) & 0x30303);

            buf += 3;

        }

    }

    if (video_size) {

        memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);

        if ((ret = av_frame_ref(rframe, s->frame)) < 0)

            return ret;

        *got_frame = 1;

    }

    return avpkt->size;

}

static av_cold int decode_close(AVCodecContext *avctx)

{

    JvContext *s = avctx->priv_data;

    av_frame_free(&s->frame);

    return 0;

}

const FFCodec ff_jv_decoder = {

    .p.name         = "jv",

    CODEC_LONG_NAME("Bitmap Brothers JV video"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_JV,

    .priv_data_size = sizeof(JvContext),

    .init           = decode_init,

    .close          = decode_close,

    FF_CODEC_DECODE_CB(decode_frame),

    .p.capabilities = AV_CODEC_CAP_DR1,

};