/*
  * SGI image encoder
  * Todd Kirby <doubleshot@pacbell.net>
  *
  * 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
  */
 
 #include "avcodec.h"
 #include "bytestream.h"
 #include "sgi.h"
 #include "rle.h"
 
 #define SGI_SINGLE_CHAN 2
 #define SGI_MULTI_CHAN 3
 
 typedef struct SgiContext {
     AVFrame picture;
 } SgiContext;
 

 static av_cold int encode_init(AVCodecContext *avctx)
 {

     SgiContext *s = avctx->priv_data;
 
     avcodec_get_frame_defaults(&s->picture);
     avctx->coded_frame = &s->picture;
 
     return 0;
 }
 
 static int encode_frame(AVCodecContext *avctx, unsigned char *buf,

                         int buf_size, void *data)
 {

     SgiContext *s = avctx->priv_data;
     AVFrame * const p = &s->picture;
     uint8_t *offsettab, *lengthtab, *in_buf, *encode_buf;
     int x, y, z, length, tablesize;
     unsigned int width, height, depth, dimension;
     unsigned char *orig_buf = buf, *end_buf = buf + buf_size;
 
     *p = *(AVFrame*)data;

     p->pict_type = AV_PICTURE_TYPE_I;

     p->key_frame = 1;
 

     width  = avctx->width;

     height = avctx->height;
 
     switch (avctx->pix_fmt) {

     case PIX_FMT_GRAY8:
         dimension = SGI_SINGLE_CHAN;
         depth     = SGI_GRAYSCALE;
         break;
     case PIX_FMT_RGB24:
         dimension = SGI_MULTI_CHAN;
         depth     = SGI_RGB;
         break;
     case PIX_FMT_RGBA:
         dimension = SGI_MULTI_CHAN;
         depth     = SGI_RGBA;
         break;
     default:
         return AVERROR_INVALIDDATA;

     }
 
     tablesize = depth * height * 4;
     length = tablesize * 2 + SGI_HEADER_SIZE;
 
     if (buf_size < length) {
         av_log(avctx, AV_LOG_ERROR, "buf_size too small(need %d, got %d)\n", length, buf_size);
         return -1;
     }
 
     /* Encode header. */
     bytestream_put_be16(&buf, SGI_MAGIC);

     bytestream_put_byte(&buf, avctx->coder_type != FF_CODER_TYPE_RAW); /* RLE 1 - VERBATIM 0*/

     bytestream_put_byte(&buf, 1); /* bytes_per_channel */
     bytestream_put_be16(&buf, dimension);
     bytestream_put_be16(&buf, width);
     bytestream_put_be16(&buf, height);
     bytestream_put_be16(&buf, depth);
 
     /* The rest are constant in this implementation. */
     bytestream_put_be32(&buf, 0L); /* pixmin */
     bytestream_put_be32(&buf, 255L); /* pixmax */
     bytestream_put_be32(&buf, 0L); /* dummy */
 
     /* name */
     memset(buf, 0, SGI_HEADER_SIZE);
     buf += 80;
 
      /* colormap */
     bytestream_put_be32(&buf, 0L);
 
     /* The rest of the 512 byte header is unused. */
     buf += 404;
     offsettab = buf;
 

     if (avctx->coder_type  != FF_CODER_TYPE_RAW) {

         /* Skip RLE offset table. */
         buf += tablesize;
         lengthtab = buf;

         /* Skip RLE length table. */
         buf += tablesize;

         /* Make an intermediate consecutive buffer. */

         if (!(encode_buf = av_malloc(width)))

             return -1;

         for (z = 0; z < depth; z++) {
             in_buf = p->data[0] + p->linesize[0] * (height - 1) + z;

             for (y = 0; y < height; y++) {
                 bytestream_put_be32(&offsettab, buf - orig_buf);

                 for (x = 0; x < width; x++)
                     encode_buf[x] = in_buf[depth * x];

                 if ((length = ff_rle_encode(buf, end_buf - buf - 1, encode_buf, 1, width, 0, 0, 0x80, 0)) < 1) {
                     av_free(encode_buf);
                     return -1;
                 }

                 buf += length;
                 bytestream_put_byte(&buf, 0);
                 bytestream_put_be32(&lengthtab, length + 1);
                 in_buf -= p->linesize[0];
             }

         }
 

         av_free(encode_buf);

     } else {
         for (z = 0; z < depth; z++) {
             in_buf = p->data[0] + p->linesize[0] * (height - 1) + z;

             for (y = 0; y < height; y++) {
                 for (x = 0; x < width * depth; x += depth)
                     bytestream_put_byte(&buf, in_buf[x]);

                 in_buf -= p->linesize[0];

             }
         }

     }

     /* total length */
     return buf - orig_buf;
 }
 

 AVCodec ff_sgi_encoder = {

     "sgi",

     AVMEDIA_TYPE_VIDEO,

     CODEC_ID_SGI,
     sizeof(SgiContext),
     encode_init,
     encode_frame,
     NULL,

     .pix_fmts= (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGBA, PIX_FMT_GRAY8, PIX_FMT_NONE},

     .long_name= NULL_IF_CONFIG_SMALL("SGI image"),

 };