/*
  * Sun Rasterfile (.sun/.ras/im{1,8,24}/.sunras) image encoder
  * Copyright (c) 2012 Aneesh Dogra (lionaneesh) <lionaneesh@gmail.com>
  *
  * This file is part of Libav.
  *
  * Libav 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.
  *
  * Libav 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 Libav; 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 "internal.h"
 #include "sunrast.h"
 
 typedef struct SUNRASTContext {
     AVFrame picture;
     PutByteContext p;
     int depth;      ///< depth of pixel
     int length;     ///< length (bytes) of image
     int type;       ///< type of file
     int maptype;    ///< type of colormap
     int maplength;  ///< length (bytes) of colormap
     int size;
 } SUNRASTContext;
 
 static void sunrast_image_write_header(AVCodecContext *avctx)
 {
     SUNRASTContext *s = avctx->priv_data;
 
     bytestream2_put_be32u(&s->p, RAS_MAGIC);
     bytestream2_put_be32u(&s->p, avctx->width);
     bytestream2_put_be32u(&s->p, avctx->height);
     bytestream2_put_be32u(&s->p, s->depth);
     bytestream2_put_be32u(&s->p, s->length);
     bytestream2_put_be32u(&s->p, s->type);
     bytestream2_put_be32u(&s->p, s->maptype);
     bytestream2_put_be32u(&s->p, s->maplength);
 }
 
 static void sunrast_image_write_image(AVCodecContext *avctx,
                                       const uint8_t *pixels,
                                       const uint32_t *palette_data,
                                       int linesize)
 {
     SUNRASTContext *s = avctx->priv_data;
     const uint8_t *ptr;

     int len, alen, x, y;

 
     if (s->maplength) {     // palettized
         PutByteContext pb_r, pb_g;
         int len = s->maplength / 3;
 
         pb_r = s->p;
         bytestream2_skip_p(&s->p, len);
         pb_g = s->p;
         bytestream2_skip_p(&s->p, len);
 
         for (x = 0; x < len; x++) {
             uint32_t pixel = palette_data[x];
 
             bytestream2_put_byteu(&pb_r, (pixel >> 16) & 0xFF);
             bytestream2_put_byteu(&pb_g, (pixel >> 8)  & 0xFF);
             bytestream2_put_byteu(&s->p,  pixel        & 0xFF);
         }
     }
 
     len  = (s->depth * avctx->width + 7) >> 3;
     alen = len + (len & 1);
     ptr  = pixels;
 
      if (s->type == RT_BYTE_ENCODED) {
         uint8_t value, value2;
         int run;
 
         ptr = pixels;
 

 #define GET_VALUE y >= avctx->height ? 0 : x >= len ? ptr[len-1] : ptr[x]

         x = 0, y = 0;

         value2 = GET_VALUE;

         while (y < avctx->height) {

             run = 1;
             value = value2;
             x++;
             if (x >= alen) {
                 x = 0;

                 ptr += linesize, y++;

             }
 
             value2 = GET_VALUE;

             while (value2 == value && run < 256 && y < avctx->height) {

                 x++;
                 run++;
                 if (x >= alen) {
                     x = 0;

                     ptr += linesize, y++;

                 }
                 value2 = GET_VALUE;
             }
 
             if (run > 2 || value == RLE_TRIGGER) {
                 bytestream2_put_byteu(&s->p, RLE_TRIGGER);
                 bytestream2_put_byteu(&s->p, run - 1);
                 if (run > 1)
                     bytestream2_put_byteu(&s->p, value);
             } else if (run == 1) {
                 bytestream2_put_byteu(&s->p, value);
             } else
                 bytestream2_put_be16u(&s->p, (value << 8) | value);
         }
 
         // update data length for header
         s->length = bytestream2_tell_p(&s->p) - 32 - s->maplength;
     } else {
         for (y = 0; y < avctx->height; y++) {
             bytestream2_put_buffer(&s->p, ptr, len);
             if (len < alen)
                 bytestream2_put_byteu(&s->p, 0);
             ptr += linesize;
         }
     }
 }
 
 static av_cold int sunrast_encode_init(AVCodecContext *avctx)
 {
     SUNRASTContext *s = avctx->priv_data;
 
     switch (avctx->coder_type) {
     case FF_CODER_TYPE_RLE:
         s->type = RT_BYTE_ENCODED;
         break;
     case FF_CODER_TYPE_RAW:
         s->type = RT_STANDARD;
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "invalid coder_type\n");
         return AVERROR(EINVAL);
     }
 
     avctx->coded_frame            = &s->picture;
     avctx->coded_frame->key_frame = 1;
     avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
     s->maptype                    = RMT_NONE;
     s->maplength                  = 0;
 
     switch (avctx->pix_fmt) {
     case PIX_FMT_MONOWHITE:
         s->depth = 1;
         break;
     case PIX_FMT_PAL8 :
         s->maptype   = RMT_EQUAL_RGB;
         s->maplength = 3 * 256;
     case PIX_FMT_GRAY8:
         s->depth = 8;
         break;
     case PIX_FMT_BGR24:
         s->depth = 24;
         break;
     default:
         return AVERROR_BUG;
     }
     s->length = avctx->height * (FFALIGN(avctx->width * s->depth, 16) >> 3);
     s->size   = 32 + s->maplength +
                 s->length * (s->type == RT_BYTE_ENCODED ? 2 : 1);
 
     return 0;
 }
 
 static int sunrast_encode_frame(AVCodecContext *avctx,  AVPacket *avpkt,
                                 const AVFrame *frame, int *got_packet_ptr)
 {
     SUNRASTContext *s = avctx->priv_data;
     int ret;
 

     if ((ret = ff_alloc_packet2(avctx, avpkt, s->size)) < 0)

         return ret;
 
     bytestream2_init_writer(&s->p, avpkt->data, avpkt->size);
     sunrast_image_write_header(avctx);
     sunrast_image_write_image(avctx, frame->data[0],
                               (const uint32_t *)frame->data[1],
                               frame->linesize[0]);
     // update data length in header after RLE
     if (s->type == RT_BYTE_ENCODED)
         AV_WB32(&avpkt->data[16], s->length);
 
     *got_packet_ptr = 1;

     avpkt->flags |= AV_PKT_FLAG_KEY;

     avpkt->size = bytestream2_tell_p(&s->p);
     return 0;
 }
 
 static const AVCodecDefault sunrast_defaults[] = {
      { "coder", "rle" },
      { NULL },
 };
 
 AVCodec ff_sunrast_encoder = {
     .name           = "sunrast",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = CODEC_ID_SUNRAST,
     .priv_data_size = sizeof(SUNRASTContext),
     .init           = sunrast_encode_init,
     .encode2        = sunrast_encode_frame,
     .defaults       = sunrast_defaults,
     .pix_fmts       = (const enum PixelFormat[]){ PIX_FMT_BGR24,
                                                   PIX_FMT_PAL8,
                                                   PIX_FMT_GRAY8,
                                                   PIX_FMT_MONOWHITE,
                                                   PIX_FMT_NONE },
     .long_name      = NULL_IF_CONFIG_SMALL("Sun Rasterfile image"),
 };