/*
  * 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 "avcodec.h"
 #include "dsputil.h"
 #include "get_bits.h"
 #include "libavutil/intreadwrite.h"
 
 typedef struct JvContext {
     DSPContext dsp;
     AVFrame    frame;
     uint32_t   palette[AVPALETTE_COUNT];
     int        palette_has_changed;
 } JvContext;
 
 static av_cold int decode_init(AVCodecContext *avctx)
 {
     JvContext *s = avctx->priv_data;
     avctx->pix_fmt = PIX_FMT_PAL8;
     dsputil_init(&s->dsp, avctx);
     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, DSPContext *dsp)
 {
     int i, j, v[2];
 
     switch (get_bits(gb, 2)) {
     case 1:
         v[0] = get_bits(gb, 8);
         dsp->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,
                         void *data, int *data_size,
                         AVPacket *avpkt)
 {
     JvContext *s           = avctx->priv_data;
     int buf_size           = avpkt->size;
     const uint8_t *buf     = avpkt->data;
     const uint8_t *buf_end = buf + buf_size;
     int video_size, video_type, i, j;
 
     video_size = AV_RL32(buf);
     video_type = buf[4];
     buf += 5;
 
     if (video_size) {
         if (avctx->reget_buffer(avctx, &s->frame) < 0) {
             av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
             return -1;
         }
 
         if (video_type == 0 || video_type == 1) {
             GetBitContext gb;

             init_get_bits(&gb, buf, FFMIN(video_size, (buf_end - buf) * 8));

 
             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->dsp);
 
             buf += video_size;
         } else if (video_type == 2) {
             if (buf + 1 <= buf_end) {
                 int v = *buf++;
                 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 < buf_end) {
         for (i = 0; i < AVPALETTE_COUNT && buf + 3 <= buf_end; i++) {
             s->palette[i] = AV_RB24(buf) << 2;
             buf += 3;
         }
         s->palette_has_changed = 1;
     }
 
     if (video_size) {
         s->frame.key_frame           = 1;

         s->frame.pict_type           = AV_PICTURE_TYPE_I;

         s->frame.palette_has_changed = s->palette_has_changed;
         s->palette_has_changed       = 0;
         memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
 
         *data_size      = sizeof(AVFrame);
         *(AVFrame*)data = s->frame;
     }
 
     return buf_size;
 }
 
 static av_cold int decode_close(AVCodecContext *avctx)
 {
     JvContext *s = avctx->priv_data;
 
     if(s->frame.data[0])
         avctx->release_buffer(avctx, &s->frame);
 
     return 0;
 }
 
 AVCodec ff_jv_decoder = {
     .name           = "jv",
     .long_name      = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV video"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = CODEC_ID_JV,
     .priv_data_size = sizeof(JvContext),
     .init           = decode_init,
     .close          = decode_close,
     .decode         = decode_frame,
     .capabilities   = CODEC_CAP_DR1,
 };