/*
  * BRender PIX (.pix) image decoder
  * Copyright (c) 2012 Aleksi Nurmi
  *
  * 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
  */
 
 /*
  * Tested against samples from I-War / Independence War and Defiance.
  * If the PIX file does not contain a palette, the
  * palette_has_changed property of the AVFrame is set to 0.
  */
 
 #include "libavutil/imgutils.h"
 #include "avcodec.h"
 #include "bytestream.h"

 #include "internal.h"

 
 typedef struct BRPixHeader {
     int format;
     unsigned int width, height;
 } BRPixHeader;
 
 static int brpix_decode_header(BRPixHeader *out, GetByteContext *pgb)
 {
     unsigned int header_len = bytestream2_get_be32(pgb);
 
     out->format = bytestream2_get_byte(pgb);
     bytestream2_skip(pgb, 2);
     out->width = bytestream2_get_be16(pgb);
     out->height = bytestream2_get_be16(pgb);
 
     // the header is at least 11 bytes long; we read the first 7
     if (header_len < 11) {
         return 0;
     }
 
     // skip the rest of the header
     bytestream2_skip(pgb, header_len-7);
 
     return 1;
 }
 
 static int brpix_decode_frame(AVCodecContext *avctx,

                               void *data, int *got_frame,

                               AVPacket *avpkt)
 {

     AVFrame *frame = data;

 
     int ret;
     GetByteContext gb;
 
     unsigned int bytes_pp;
 
     unsigned int magic[4];
     unsigned int chunk_type;
     unsigned int data_len;
     BRPixHeader hdr;
 
     bytestream2_init(&gb, avpkt->data, avpkt->size);
 
     magic[0] = bytestream2_get_be32(&gb);
     magic[1] = bytestream2_get_be32(&gb);
     magic[2] = bytestream2_get_be32(&gb);
     magic[3] = bytestream2_get_be32(&gb);
 
     if (magic[0] != 0x12 ||
         magic[1] != 0x8 ||
         magic[2] != 0x2 ||
         magic[3] != 0x2) {
         av_log(avctx, AV_LOG_ERROR, "Not a BRender PIX file\n");
         return AVERROR_INVALIDDATA;
     }
 
     chunk_type = bytestream2_get_be32(&gb);
     if (chunk_type != 0x3 && chunk_type != 0x3d) {
         av_log(avctx, AV_LOG_ERROR, "Invalid chunk type %d\n", chunk_type);
         return AVERROR_INVALIDDATA;
     }
 
     ret = brpix_decode_header(&hdr, &gb);
     if (!ret) {
         av_log(avctx, AV_LOG_ERROR, "Invalid header length\n");
         return AVERROR_INVALIDDATA;
     }
     switch (hdr.format) {
     case 3:
         avctx->pix_fmt = AV_PIX_FMT_PAL8;
         bytes_pp = 1;
         break;
     case 4:
         avctx->pix_fmt = AV_PIX_FMT_RGB555BE;
         bytes_pp = 2;
         break;
     case 5:
         avctx->pix_fmt = AV_PIX_FMT_RGB565BE;
         bytes_pp = 2;
         break;
     case 6:
         avctx->pix_fmt = AV_PIX_FMT_RGB24;
         bytes_pp = 3;
         break;
     case 7:
         avctx->pix_fmt = AV_PIX_FMT_0RGB;
         bytes_pp = 4;
         break;
     case 18:
         avctx->pix_fmt = AV_PIX_FMT_GRAY8A;
         bytes_pp = 2;
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "Format %d is not supported\n",
                                     hdr.format);
         return AVERROR_PATCHWELCOME;
     }
 

     if ((ret = ff_set_dimensions(avctx, hdr.width, hdr.height)) < 0)
         return ret;

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

         return ret;
 
     chunk_type = bytestream2_get_be32(&gb);
 
     if (avctx->pix_fmt == AV_PIX_FMT_PAL8 &&
         (chunk_type == 0x3 || chunk_type == 0x3d)) {
         BRPixHeader palhdr;

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

         int i;

 
         ret = brpix_decode_header(&palhdr, &gb);
         if (!ret) {
             av_log(avctx, AV_LOG_ERROR, "Invalid palette header length\n");
             return AVERROR_INVALIDDATA;
         }
         if (palhdr.format != 7) {
             av_log(avctx, AV_LOG_ERROR, "Palette is not in 0RGB format\n");
             return AVERROR_INVALIDDATA;
         }
 
         chunk_type = bytestream2_get_be32(&gb);
         data_len = bytestream2_get_be32(&gb);
         bytestream2_skip(&gb, 8);
         if (chunk_type != 0x21 || data_len != 1032 ||
             bytestream2_get_bytes_left(&gb) < 1032) {
             av_log(avctx, AV_LOG_ERROR, "Invalid palette data\n");
             return AVERROR_INVALIDDATA;
         }
         // convert 0RGB to machine endian format (ARGB32)

         for (i = 0; i < 256; ++i) {

             bytestream2_skipu(&gb, 1);
             *pal_out++ = (0xFFU << 24) | bytestream2_get_be24u(&gb);
         }
         bytestream2_skip(&gb, 8);
 

         frame->palette_has_changed = 1;

 
         chunk_type = bytestream2_get_be32(&gb);

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

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

         int i;
 
         for (i = 0; i < 256; ++i) {
             *pal_out++ = (0xFFU << 24) | (i * 0x010101);
         }

         frame->palette_has_changed = 1;

     }
 
     data_len = bytestream2_get_be32(&gb);
     bytestream2_skip(&gb, 8);
 
     // read the image data to the buffer
     {
         unsigned int bytes_per_scanline = bytes_pp * hdr.width;
         unsigned int bytes_left = bytestream2_get_bytes_left(&gb);
 
         if (chunk_type != 0x21 || data_len != bytes_left ||
             bytes_left / bytes_per_scanline < hdr.height)
         {
             av_log(avctx, AV_LOG_ERROR, "Invalid image data\n");
             return AVERROR_INVALIDDATA;
         }
 

         av_image_copy_plane(frame->data[0], frame->linesize[0],

                             avpkt->data + bytestream2_tell(&gb),
                             bytes_per_scanline,
                             bytes_per_scanline, hdr.height);
     }
 

     *got_frame = 1;

 
     return avpkt->size;
 }
 
 AVCodec ff_brender_pix_decoder = {
     .name           = "brender_pix",

     .long_name      = NULL_IF_CONFIG_SMALL("BRender PIX image"),

     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_BRENDER_PIX,
     .decode         = brpix_decode_frame,
     .capabilities   = CODEC_CAP_DR1,
 };