/*
  * CDXL video decoder
  * Copyright (c) 2011-2012 Paul B Mahol
  *

  * 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
  * Commodore CDXL video decoder
  * @author Paul B Mahol
  */
 

 #define UNCHECKED_BITSTREAM_READER 1
 

 #include "libavutil/intreadwrite.h"
 #include "libavutil/imgutils.h"
 #include "avcodec.h"

 #include "bytestream.h"

 #include "get_bits.h"

 #include "internal.h"

 #define BIT_PLANAR   0x00

 #define CHUNKY       0x20
 #define BYTE_PLANAR  0x40

 #define BIT_LINE     0x80
 #define BYTE_LINE    0xC0
 

 typedef struct CDXLVideoContext {

     AVCodecContext *avctx;
     int            bpp;

     int            format;
     int            padded_bits;

     const uint8_t  *palette;
     int            palette_size;
     const uint8_t  *video;
     int            video_size;
     uint8_t        *new_video;
     int            new_video_size;
 } CDXLVideoContext;
 
 static av_cold int cdxl_decode_init(AVCodecContext *avctx)
 {
     CDXLVideoContext *c = avctx->priv_data;
 
     c->new_video_size = 0;
     c->avctx          = avctx;
 
     return 0;
 }
 
 static void import_palette(CDXLVideoContext *c, uint32_t *new_palette)
 {
     int i;
 
     for (i = 0; i < c->palette_size / 2; i++) {
         unsigned rgb = AV_RB16(&c->palette[i * 2]);
         unsigned r   = ((rgb >> 8) & 0xF) * 0x11;
         unsigned g   = ((rgb >> 4) & 0xF) * 0x11;
         unsigned b   =  (rgb       & 0xF) * 0x11;

         AV_WN32(&new_palette[i], (0xFFU << 24) | (r << 16) | (g << 8) | b);

     }
 }
 

 static void bitplanar2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)

 {
     GetBitContext gb;
     int x, y, plane;
 

     if (init_get_bits8(&gb, c->video, c->video_size) < 0)
         return;

     for (plane = 0; plane < c->bpp; plane++) {
         for (y = 0; y < c->avctx->height; y++) {
             for (x = 0; x < c->avctx->width; x++)

                 out[linesize * y + x] |= get_bits1(&gb) << plane;

             skip_bits(&gb, c->padded_bits);
         }
     }
 }
 
 static void bitline2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)
 {
     GetBitContext  gb;
     int x, y, plane;
 

     if (init_get_bits8(&gb, c->video, c->video_size) < 0)
         return;

     for (y = 0; y < c->avctx->height; y++) {
         for (plane = 0; plane < c->bpp; plane++) {
             for (x = 0; x < c->avctx->width; x++)
                 out[linesize * y + x] |= get_bits1(&gb) << plane;
             skip_bits(&gb, c->padded_bits);

         }
     }

 }
 

 static void chunky2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)
 {
     GetByteContext gb;
     int y;
 
     bytestream2_init(&gb, c->video, c->video_size);
     for (y = 0; y < c->avctx->height; y++) {
         bytestream2_get_buffer(&gb, out + linesize * y, c->avctx->width * 3);
     }
 }
 

 static void import_format(CDXLVideoContext *c, int linesize, uint8_t *out)
 {
     memset(out, 0, linesize * c->avctx->height);
 
     switch (c->format) {
     case BIT_PLANAR:
         bitplanar2chunky(c, linesize, out);
         break;
     case BIT_LINE:
         bitline2chunky(c, linesize, out);
         break;

     case CHUNKY:
         chunky2chunky(c, linesize, out);
         break;

     }
 }
 

 static void cdxl_decode_rgb(CDXLVideoContext *c, AVFrame *frame)

 {

     uint32_t *new_palette = (uint32_t *)frame->data[1];

     memset(frame->data[1], 0, AVPALETTE_SIZE);

     import_palette(c, new_palette);

     import_format(c, frame->linesize[0], frame->data[0]);

 }
 

 static void cdxl_decode_raw(CDXLVideoContext *c, AVFrame *frame)
 {
     import_format(c, frame->linesize[0], frame->data[0]);
 }
 

 static void cdxl_decode_ham6(CDXLVideoContext *c, AVFrame *frame)

 {
     AVCodecContext *avctx = c->avctx;
     uint32_t new_palette[16], r, g, b;
     uint8_t *ptr, *out, index, op;
     int x, y;
 
     ptr = c->new_video;

     out = frame->data[0];

 
     import_palette(c, new_palette);

     import_format(c, avctx->width, c->new_video);

 
     for (y = 0; y < avctx->height; y++) {
         r = new_palette[0] & 0xFF0000;
         g = new_palette[0] & 0xFF00;
         b = new_palette[0] & 0xFF;
         for (x = 0; x < avctx->width; x++) {
             index  = *ptr++;
             op     = index >> 4;
             index &= 15;
             switch (op) {
             case 0:
                 r = new_palette[index] & 0xFF0000;
                 g = new_palette[index] & 0xFF00;
                 b = new_palette[index] & 0xFF;
                 break;
             case 1:
                 b = index * 0x11;
                 break;
             case 2:
                 r = index * 0x11 << 16;
                 break;
             case 3:
                 g = index * 0x11 << 8;
                 break;
             }

             AV_WL24(out + x * 3, r | g | b);

         }

         out += frame->linesize[0];

     }
 }
 

 static void cdxl_decode_ham8(CDXLVideoContext *c, AVFrame *frame)

 {
     AVCodecContext *avctx = c->avctx;
     uint32_t new_palette[64], r, g, b;
     uint8_t *ptr, *out, index, op;
     int x, y;
 
     ptr = c->new_video;

     out = frame->data[0];

 
     import_palette(c, new_palette);

     import_format(c, avctx->width, c->new_video);

 
     for (y = 0; y < avctx->height; y++) {
         r = new_palette[0] & 0xFF0000;
         g = new_palette[0] & 0xFF00;
         b = new_palette[0] & 0xFF;
         for (x = 0; x < avctx->width; x++) {
             index  = *ptr++;
             op     = index >> 6;
             index &= 63;
             switch (op) {
             case 0:
                 r = new_palette[index] & 0xFF0000;
                 g = new_palette[index] & 0xFF00;
                 b = new_palette[index] & 0xFF;
                 break;
             case 1:
                 b = (index <<  2) | (b & 3);
                 break;
             case 2:
                 r = (index << 18) | (r & (3 << 16));
                 break;
             case 3:
                 g = (index << 10) | (g & (3 << 8));
                 break;
             }

             AV_WL24(out + x * 3, r | g | b);

         }

         out += frame->linesize[0];

     }
 }
 
 static int cdxl_decode_frame(AVCodecContext *avctx, void *data,

                              int *got_frame, AVPacket *pkt)

 {
     CDXLVideoContext *c = avctx->priv_data;

     AVFrame * const p = data;

     int ret, w, h, encoding, aligned_width, buf_size = pkt->size;

     const uint8_t *buf = pkt->data;
 
     if (buf_size < 32)
         return AVERROR_INVALIDDATA;
     encoding        = buf[1] & 7;

     c->format       = buf[1] & 0xE0;

     w               = AV_RB16(&buf[14]);
     h               = AV_RB16(&buf[16]);
     c->bpp          = buf[19];
     c->palette_size = AV_RB16(&buf[20]);
     c->palette      = buf + 32;
     c->video        = c->palette + c->palette_size;
     c->video_size   = buf_size - c->palette_size - 32;
 
     if (c->palette_size > 512)
         return AVERROR_INVALIDDATA;
     if (buf_size < c->palette_size + 32)
         return AVERROR_INVALIDDATA;
     if (c->bpp < 1)
         return AVERROR_INVALIDDATA;

     if (c->format != BIT_PLANAR && c->format != BIT_LINE && c->format != CHUNKY) {

         avpriv_request_sample(avctx, "Pixel format 0x%0x", c->format);

         return AVERROR_PATCHWELCOME;
     }
 

     if ((ret = ff_set_dimensions(avctx, w, h)) < 0)

         return ret;
 

     if (c->format == CHUNKY)
         aligned_width = avctx->width;
     else
         aligned_width = FFALIGN(c->avctx->width, 16);

     c->padded_bits  = aligned_width - c->avctx->width;

     if (c->video_size < aligned_width * avctx->height * (int64_t)c->bpp / 8)

         return AVERROR_INVALIDDATA;

     if (!encoding && c->palette_size && c->bpp <= 8 && c->format != CHUNKY) {

         avctx->pix_fmt = AV_PIX_FMT_PAL8;

     } else if (encoding == 1 && (c->bpp == 6 || c->bpp == 8) && c->format != CHUNKY) {

         if (c->palette_size != (1 << (c->bpp - 1)))
             return AVERROR_INVALIDDATA;

         avctx->pix_fmt = AV_PIX_FMT_BGR24;

     } else if (!encoding && c->bpp == 24 && c->format == CHUNKY &&
                !c->palette_size) {
         avctx->pix_fmt = AV_PIX_FMT_RGB24;

     } else {

         avpriv_request_sample(avctx, "Encoding %d, bpp %d and format 0x%x",
                               encoding, c->bpp, c->format);

         return AVERROR_PATCHWELCOME;
     }
 

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

         return ret;
     p->pict_type = AV_PICTURE_TYPE_I;
 
     if (encoding) {
         av_fast_padded_malloc(&c->new_video, &c->new_video_size,

                               h * w + AV_INPUT_BUFFER_PADDING_SIZE);

         if (!c->new_video)
             return AVERROR(ENOMEM);
         if (c->bpp == 8)

             cdxl_decode_ham8(c, p);

         else

             cdxl_decode_ham6(c, p);

     } else if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {

         cdxl_decode_rgb(c, p);

     } else {
         cdxl_decode_raw(c, p);

     }

     *got_frame = 1;

 
     return buf_size;
 }
 
 static av_cold int cdxl_decode_end(AVCodecContext *avctx)
 {
     CDXLVideoContext *c = avctx->priv_data;
 

     av_freep(&c->new_video);

 
     return 0;
 }
 
 AVCodec ff_cdxl_decoder = {
     .name           = "cdxl",

     .long_name      = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_CDXL,

     .priv_data_size = sizeof(CDXLVideoContext),
     .init           = cdxl_decode_init,
     .close          = cdxl_decode_end,
     .decode         = cdxl_decode_frame,

     .capabilities   = AV_CODEC_CAP_DR1,

 };