/*
  * Zip Motion Blocks Video (ZMBV) decoder
  * 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
  */
 
 /**

  * @file

  * Zip Motion Blocks Video decoder
  */
 
 #include <stdio.h>
 #include <stdlib.h>
 

 #include "libavutil/common.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/intreadwrite.h"

 #include "avcodec.h"

 #include "internal.h"

 
 #include <zlib.h>
 
 #define ZMBV_KEYFRAME 1
 #define ZMBV_DELTAPAL 2
 
 enum ZmbvFormat {
     ZMBV_FMT_NONE  = 0,
     ZMBV_FMT_1BPP  = 1,
     ZMBV_FMT_2BPP  = 2,
     ZMBV_FMT_4BPP  = 3,
     ZMBV_FMT_8BPP  = 4,
     ZMBV_FMT_15BPP = 5,
     ZMBV_FMT_16BPP = 6,
     ZMBV_FMT_24BPP = 7,
     ZMBV_FMT_32BPP = 8
 };
 
 /*
  * Decoder context
  */
 typedef struct ZmbvContext {
     AVCodecContext *avctx;
 
     int bpp;
     unsigned int decomp_size;
     uint8_t* decomp_buf;
     uint8_t pal[768];
     uint8_t *prev, *cur;
     int width, height;
     int fmt;
     int comp;
     int flags;

     int stride;

     int bw, bh, bx, by;
     int decomp_len;
     z_stream zstream;
     int (*decode_intra)(struct ZmbvContext *c);
     int (*decode_xor)(struct ZmbvContext *c);
 } ZmbvContext;
 
 /**
  * Decode XOR'ed frame - 8bpp version
  */
 
 static int zmbv_decode_xor_8(ZmbvContext *c)
 {
     uint8_t *src = c->decomp_buf;
     uint8_t *output, *prev;
     int8_t *mvec;
     int x, y;
     int d, dx, dy, bw2, bh2;
     int block;
     int i, j;
     int mx, my;
 
     output = c->cur;
     prev = c->prev;
 

     if (c->flags & ZMBV_DELTAPAL) {
         for (i = 0; i < 768; i++)

             c->pal[i] ^= *src++;
     }
 
     mvec = (int8_t*)src;
     src += ((c->bx * c->by * 2 + 3) & ~3);
 
     block = 0;

     for (y = 0; y < c->height; y += c->bh) {

         bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

         for (x = 0; x < c->width; x += c->bw) {

             uint8_t *out, *tprev;
 
             d = mvec[block] & 1;
             dx = mvec[block] >> 1;
             dy = mvec[block + 1] >> 1;
             block += 2;
 
             bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
 
             /* copy block - motion vectors out of bounds are used to zero blocks */
             out = output + x;
             tprev = prev + x + dx + dy * c->width;
             mx = x + dx;
             my = y + dy;

             for (j = 0; j < bh2; j++) {
                 if (my + j < 0 || my + j >= c->height) {

                     memset(out, 0, bw2);
                 } else {

                     for (i = 0; i < bw2; i++) {
                         if (mx + i < 0 || mx + i >= c->width)

                             out[i] = 0;
                         else
                             out[i] = tprev[i];
                     }
                 }
                 out += c->width;
                 tprev += c->width;
             }
 

             if (d) { /* apply XOR'ed difference */

                 out = output + x;

                 for (j = 0; j < bh2; j++) {
                     for (i = 0; i < bw2; i++)

                         out[i] ^= *src++;
                     out += c->width;
                 }
             }
         }
         output += c->width * c->bh;
         prev += c->width * c->bh;
     }

     if (src - c->decomp_buf != c->decomp_len)

         av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",

                src-c->decomp_buf, c->decomp_len);

     return 0;
 }
 
 /**

  * Decode XOR'ed frame - 15bpp and 16bpp version
  */
 
 static int zmbv_decode_xor_16(ZmbvContext *c)
 {
     uint8_t *src = c->decomp_buf;
     uint16_t *output, *prev;
     int8_t *mvec;
     int x, y;
     int d, dx, dy, bw2, bh2;
     int block;
     int i, j;
     int mx, my;
 
     output = (uint16_t*)c->cur;
     prev = (uint16_t*)c->prev;
 
     mvec = (int8_t*)src;
     src += ((c->bx * c->by * 2 + 3) & ~3);
 
     block = 0;

     for (y = 0; y < c->height; y += c->bh) {

         bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

         for (x = 0; x < c->width; x += c->bw) {

             uint16_t *out, *tprev;
 
             d = mvec[block] & 1;
             dx = mvec[block] >> 1;
             dy = mvec[block + 1] >> 1;
             block += 2;
 
             bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
 
             /* copy block - motion vectors out of bounds are used to zero blocks */
             out = output + x;
             tprev = prev + x + dx + dy * c->width;
             mx = x + dx;
             my = y + dy;

             for (j = 0; j < bh2; j++) {
                 if (my + j < 0 || my + j >= c->height) {

                     memset(out, 0, bw2 * 2);
                 } else {

                     for (i = 0; i < bw2; i++) {
                         if (mx + i < 0 || mx + i >= c->width)

                             out[i] = 0;
                         else
                             out[i] = tprev[i];
                     }
                 }
                 out += c->width;
                 tprev += c->width;
             }
 

             if (d) { /* apply XOR'ed difference */

                 out = output + x;

                 for (j = 0; j < bh2; j++){
                     for (i = 0; i < bw2; i++) {

                         out[i] ^= *((uint16_t*)src);
                         src += 2;
                     }
                     out += c->width;
                 }
             }
         }
         output += c->width * c->bh;
         prev += c->width * c->bh;
     }

     if (src - c->decomp_buf != c->decomp_len)

         av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",

                src-c->decomp_buf, c->decomp_len);

     return 0;
 }
 
 #ifdef ZMBV_ENABLE_24BPP
 /**

  * Decode XOR'ed frame - 24bpp version
  */
 
 static int zmbv_decode_xor_24(ZmbvContext *c)
 {
     uint8_t *src = c->decomp_buf;
     uint8_t *output, *prev;
     int8_t *mvec;
     int x, y;
     int d, dx, dy, bw2, bh2;
     int block;
     int i, j;
     int mx, my;
     int stride;
 
     output = c->cur;
     prev = c->prev;
 
     stride = c->width * 3;
     mvec = (int8_t*)src;
     src += ((c->bx * c->by * 2 + 3) & ~3);
 
     block = 0;

     for (y = 0; y < c->height; y += c->bh) {

         bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

         for (x = 0; x < c->width; x += c->bw) {

             uint8_t *out, *tprev;
 
             d = mvec[block] & 1;
             dx = mvec[block] >> 1;
             dy = mvec[block + 1] >> 1;
             block += 2;
 
             bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
 
             /* copy block - motion vectors out of bounds are used to zero blocks */
             out = output + x * 3;
             tprev = prev + (x + dx) * 3 + dy * stride;
             mx = x + dx;
             my = y + dy;

             for (j = 0; j < bh2; j++) {
                 if (my + j < 0 || my + j >= c->height) {

                     memset(out, 0, bw2 * 3);
                 } else {

                     for (i = 0; i < bw2; i++){
                         if (mx + i < 0 || mx + i >= c->width) {

                             out[i * 3 + 0] = 0;
                             out[i * 3 + 1] = 0;
                             out[i * 3 + 2] = 0;
                         } else {
                             out[i * 3 + 0] = tprev[i * 3 + 0];
                             out[i * 3 + 1] = tprev[i * 3 + 1];
                             out[i * 3 + 2] = tprev[i * 3 + 2];
                         }
                     }
                 }
                 out += stride;
                 tprev += stride;
             }
 

             if (d) { /* apply XOR'ed difference */

                 out = output + x * 3;

                 for (j = 0; j < bh2; j++) {
                     for (i = 0; i < bw2; i++) {

                         out[i * 3 + 0] ^= *src++;
                         out[i * 3 + 1] ^= *src++;
                         out[i * 3 + 2] ^= *src++;
                     }
                     out += stride;
                 }
             }
         }
         output += stride * c->bh;
         prev += stride * c->bh;
     }

     if (src - c->decomp_buf != c->decomp_len)
         av_log(c->avctx, AV_LOG_ERROR, "Used %i of %i bytes\n",
                src-c->decomp_buf, c->decomp_len);

     return 0;
 }

 #endif //ZMBV_ENABLE_24BPP
 
 /**
  * Decode XOR'ed frame - 32bpp version
  */
 
 static int zmbv_decode_xor_32(ZmbvContext *c)
 {
     uint8_t *src = c->decomp_buf;
     uint32_t *output, *prev;
     int8_t *mvec;
     int x, y;
     int d, dx, dy, bw2, bh2;
     int block;
     int i, j;
     int mx, my;
 
     output = (uint32_t*)c->cur;
     prev = (uint32_t*)c->prev;
 
     mvec = (int8_t*)src;
     src += ((c->bx * c->by * 2 + 3) & ~3);
 
     block = 0;

     for (y = 0; y < c->height; y += c->bh) {

         bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

         for (x = 0; x < c->width; x += c->bw) {

             uint32_t *out, *tprev;
 
             d = mvec[block] & 1;
             dx = mvec[block] >> 1;
             dy = mvec[block + 1] >> 1;
             block += 2;
 
             bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);
 
             /* copy block - motion vectors out of bounds are used to zero blocks */
             out = output + x;
             tprev = prev + x + dx + dy * c->width;
             mx = x + dx;
             my = y + dy;

             for (j = 0; j < bh2; j++) {
                 if (my + j < 0 || my + j >= c->height) {

                     memset(out, 0, bw2 * 4);
                 } else {

                     for (i = 0; i < bw2; i++){
                         if (mx + i < 0 || mx + i >= c->width)

                             out[i] = 0;
                         else
                             out[i] = tprev[i];
                     }
                 }
                 out += c->width;
                 tprev += c->width;
             }
 

             if (d) { /* apply XOR'ed difference */

                 out = output + x;

                 for (j = 0; j < bh2; j++){
                     for (i = 0; i < bw2; i++) {
                         out[i] ^= *((uint32_t *) src);

                         src += 4;
                     }
                     out += c->width;
                 }
             }
         }
         output += c->width * c->bh;

         prev   += c->width * c->bh;

     }

     if (src - c->decomp_buf != c->decomp_len)

         av_log(c->avctx, AV_LOG_ERROR, "Used %"PTRDIFF_SPECIFIER" of %i bytes\n",

                src-c->decomp_buf, c->decomp_len);

     return 0;
 }

 
 /**
  * Decode intraframe
  */
 static int zmbv_decode_intra(ZmbvContext *c)
 {
     uint8_t *src = c->decomp_buf;
 
     /* make the palette available on the way out */
     if (c->fmt == ZMBV_FMT_8BPP) {
         memcpy(c->pal, src, 768);
         src += 768;
     }
 
     memcpy(c->cur, src, c->width * c->height * (c->bpp / 8));
     return 0;
 }
 

 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)

 {

     AVFrame *frame = data;

     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;

     ZmbvContext * const c = avctx->priv_data;

     int zret = Z_OK; // Zlib return code
     int len = buf_size;

     int hi_ver, lo_ver, ret;

 
     /* parse header */

     if (len < 1)
         return AVERROR_INVALIDDATA;

     c->flags = buf[0];
     buf++; len--;

     if (c->flags & ZMBV_KEYFRAME) {

         void *decode_intra = NULL;
         c->decode_intra= NULL;

 
         if (len < 6)
             return AVERROR_INVALIDDATA;

         hi_ver = buf[0];
         lo_ver = buf[1];
         c->comp = buf[2];
         c->fmt = buf[3];
         c->bw = buf[4];
         c->bh = buf[5];

         c->decode_intra = NULL;
         c->decode_xor = NULL;

 
         buf += 6;
         len -= 6;

         av_log(avctx, AV_LOG_DEBUG,
                "Flags=%X ver=%i.%i comp=%i fmt=%i blk=%ix%i\n",
                c->flags,hi_ver,lo_ver,c->comp,c->fmt,c->bw,c->bh);
         if (hi_ver != 0 || lo_ver != 1) {

             avpriv_request_sample(avctx, "Version %i.%i", hi_ver, lo_ver);

             return AVERROR_PATCHWELCOME;

         }

         if (c->bw == 0 || c->bh == 0) {

             avpriv_request_sample(avctx, "Block size %ix%i", c->bw, c->bh);

             return AVERROR_PATCHWELCOME;

         }

         if (c->comp != 0 && c->comp != 1) {

             avpriv_request_sample(avctx, "Compression type %i", c->comp);

             return AVERROR_PATCHWELCOME;

         }

         switch (c->fmt) {

         case ZMBV_FMT_8BPP:
             c->bpp = 8;

             decode_intra = zmbv_decode_intra;

             c->decode_xor = zmbv_decode_xor_8;

             avctx->pix_fmt = AV_PIX_FMT_PAL8;
             c->stride = c->width;

             break;
         case ZMBV_FMT_15BPP:
         case ZMBV_FMT_16BPP:
             c->bpp = 16;

             decode_intra = zmbv_decode_intra;

             c->decode_xor = zmbv_decode_xor_16;

             if (c->fmt == ZMBV_FMT_15BPP)
                 avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
             else
                 avctx->pix_fmt = AV_PIX_FMT_RGB565LE;
             c->stride = c->width * 2;

             break;
 #ifdef ZMBV_ENABLE_24BPP
         case ZMBV_FMT_24BPP:
             c->bpp = 24;

             decode_intra = zmbv_decode_intra;

             c->decode_xor = zmbv_decode_xor_24;

             avctx->pix_fmt = AV_PIX_FMT_RGB24;
             c->stride = c->width * 3;

             break;
 #endif //ZMBV_ENABLE_24BPP
         case ZMBV_FMT_32BPP:
             c->bpp = 32;

             decode_intra = zmbv_decode_intra;

             c->decode_xor = zmbv_decode_xor_32;

             avctx->pix_fmt = AV_PIX_FMT_BGR0;

             c->stride = c->width * 4;

             break;
         default:
             c->decode_xor = NULL;

             avpriv_request_sample(avctx, "Format %i", c->fmt);

             return AVERROR_PATCHWELCOME;

         }

         zret = inflateReset(&c->zstream);
         if (zret != Z_OK) {
             av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);

             return AVERROR_UNKNOWN;

         }

         c->cur  = av_realloc_f(c->cur, avctx->width * avctx->height,  (c->bpp / 8));

         c->prev = av_realloc_f(c->prev, avctx->width * avctx->height,  (c->bpp / 8));

         c->bx = (c->width + c->bw - 1) / c->bw;
         c->by = (c->height+ c->bh - 1) / c->bh;

         if (!c->cur || !c->prev)

             return AVERROR(ENOMEM);

         memset(c->cur, 0, avctx->width * avctx->height * (c->bpp / 8));
         memset(c->prev, 0, avctx->width * avctx->height * (c->bpp / 8));

         c->decode_intra= decode_intra;

     }
 

     if (!c->decode_intra) {

         av_log(avctx, AV_LOG_ERROR, "Error! Got no format or no keyframe!\n");
         return AVERROR_INVALIDDATA;
     }

     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)

         return ret;
 

     if (c->comp == 0) { // uncompressed data

         if (c->decomp_size < len) {

             av_log(avctx, AV_LOG_ERROR, "Buffer too small\n");

             return AVERROR_INVALIDDATA;
         }

         memcpy(c->decomp_buf, buf, len);
     } else { // ZLIB-compressed data
         c->zstream.total_in = c->zstream.total_out = 0;

         c->zstream.next_in = (uint8_t*)buf;

         c->zstream.avail_in = len;
         c->zstream.next_out = c->decomp_buf;
         c->zstream.avail_out = c->decomp_size;

         zret = inflate(&c->zstream, Z_SYNC_FLUSH);
         if (zret != Z_OK && zret != Z_STREAM_END) {
             av_log(avctx, AV_LOG_ERROR, "inflate error %d\n", zret);
             return AVERROR_INVALIDDATA;
         }

         c->decomp_len = c->zstream.total_out;
     }

     if (c->flags & ZMBV_KEYFRAME) {

         frame->key_frame = 1;
         frame->pict_type = AV_PICTURE_TYPE_I;

         c->decode_intra(c);
     } else {

         frame->key_frame = 0;
         frame->pict_type = AV_PICTURE_TYPE_P;

         if (c->decomp_len)

             c->decode_xor(c);

     }
 
     /* update frames */
     {
         uint8_t *out, *src;

         int j;

         out = frame->data[0];

         src = c->cur;

         switch (c->fmt) {

         case ZMBV_FMT_8BPP:

             for (j = 0; j < 256; j++)

                 AV_WN32(&frame->data[1][j * 4], 0xFFU << 24 | AV_RB24(&c->pal[j * 3]));

         case ZMBV_FMT_15BPP:
         case ZMBV_FMT_16BPP:
 #ifdef ZMBV_ENABLE_24BPP
         case ZMBV_FMT_24BPP:

 #endif

         case ZMBV_FMT_32BPP:

             av_image_copy_plane(out, frame->linesize[0], src, c->stride,
                                 c->stride, c->height);

             break;
         default:
             av_log(avctx, AV_LOG_ERROR, "Cannot handle format %i\n", c->fmt);

         }

         FFSWAP(uint8_t *, c->cur, c->prev);

     }

     *got_frame = 1;

 
     /* always report that the buffer was completely consumed */
     return buf_size;
 }
 

 static av_cold int decode_init(AVCodecContext *avctx)

 {

     ZmbvContext * const c = avctx->priv_data;

     int zret; // Zlib return code
 
     c->avctx = avctx;
 
     c->width = avctx->width;
     c->height = avctx->height;
 

     c->bpp = avctx->bits_per_coded_sample;

 
     // Needed if zlib unused or init aborted before inflateInit

     memset(&c->zstream, 0, sizeof(z_stream));

     c->decomp_size = (avctx->width + 255) * 4 * (avctx->height + 64);
 
     /* Allocate decompression buffer */
     if (c->decomp_size) {

         if (!(c->decomp_buf = av_mallocz(c->decomp_size))) {

             av_log(avctx, AV_LOG_ERROR,
                    "Can't allocate decompression buffer.\n");

             return AVERROR(ENOMEM);

         }
     }
 
     c->zstream.zalloc = Z_NULL;
     c->zstream.zfree = Z_NULL;
     c->zstream.opaque = Z_NULL;

     zret = inflateInit(&c->zstream);

     if (zret != Z_OK) {
         av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);

         return AVERROR_UNKNOWN;

     }
 
     return 0;
 }
 

 static av_cold int decode_end(AVCodecContext *avctx)

 {

     ZmbvContext * const c = avctx->priv_data;

 
     av_freep(&c->decomp_buf);
 

     inflateEnd(&c->zstream);

     av_freep(&c->cur);
     av_freep(&c->prev);

 
     return 0;
 }
 

 AVCodec ff_zmbv_decoder = {

     .name           = "zmbv",

     .long_name      = NULL_IF_CONFIG_SMALL("Zip Motion Blocks Video"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_ZMBV,

     .priv_data_size = sizeof(ZmbvContext),
     .init           = decode_init,
     .close          = decode_end,
     .decode         = decode_frame,

     .capabilities   = AV_CODEC_CAP_DR1,

 };