/*
  * Copyright (c) 2011 Derek Buitenhuis
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public
  * License as published by the Free Software Foundation;
  * version 2 of the License.
  *
  * 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
  * General Public License for more details.
  *
  * You should have received a copy of the GNU 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
  * Known FOURCCs:
  *     'ULY0' (YCbCr 4:2:0), 'ULY2' (YCbCr 4:2:2), 'ULRG' (RGB), 'ULRA' (RGBA)
  */
 
 extern "C" {
 #include "avcodec.h"
 }
 
 #include <stdlib.h>
 #include <utvideo/utvideo.h>
 #include <utvideo/Codec.h>
 
 #include "get_bits.h"
 
 typedef struct {
     uint32_t version;
     uint32_t original_format;

     uint32_t frameinfo_size;

     uint32_t flags;
 } UtVideoExtra;
 
 typedef struct {
     CCodec *codec;

     unsigned int buf_size;

     uint8_t *output;
 } UtVideoContext;
 
 static av_cold int utvideo_decode_init(AVCodecContext *avctx)
 {
     UtVideoContext *utv = (UtVideoContext *)avctx->priv_data;
     UtVideoExtra info;

     int format;

     int begin_ret;

     if (avctx->extradata_size != 4*4) {

         av_log(avctx, AV_LOG_ERROR, "Extradata size mismatch.\n");
         return -1;
     }
 
     /* Read extradata */
     info.version = AV_RL32(avctx->extradata);
     info.original_format = AV_RL32(avctx->extradata + 4);

     info.frameinfo_size = AV_RL32(avctx->extradata + 8);

     info.flags = AV_RL32(avctx->extradata + 12);
 

     /* Pick format based on FOURCC */

     switch (avctx->codec_tag) {
     case MKTAG('U', 'L', 'Y', '0'):
         avctx->pix_fmt = PIX_FMT_YUV420P;
         format = UTVF_YV12;
         break;
     case MKTAG('U', 'L', 'Y', '2'):
         avctx->pix_fmt = PIX_FMT_YUYV422;
         format = UTVF_YUY2;
         break;
     case MKTAG('U', 'L', 'R', 'G'):
         avctx->pix_fmt = PIX_FMT_BGR24;
         format = UTVF_RGB24_WIN;
         break;
     case MKTAG('U', 'L', 'R', 'A'):
         avctx->pix_fmt = PIX_FMT_RGB32;
         format = UTVF_RGB32_WIN;
         break;
     default:
         av_log(avctx, AV_LOG_ERROR,
               "Not a Ut Video FOURCC: %X\n", avctx->codec_tag);
         return -1;

     }
 
     /* Only allocate the buffer once */

     utv->buf_size = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
     utv->output = (uint8_t *)av_malloc(utv->buf_size * sizeof(uint8_t));

     if (utv->output == NULL) {

         av_log(avctx, AV_LOG_ERROR, "Unable to allocate output buffer.\n");
         return -1;
     }
 

     /* Allocate the output frame */

     avctx->coded_frame = avcodec_alloc_frame();
 
     /* Ut Video only supports 8-bit */
     avctx->bits_per_raw_sample = 8;
 
     /* Is it interlaced? */
     avctx->coded_frame->interlaced_frame = info.flags & 0x800 ? 1 : 0;
 
     /* Apparently Ut Video doesn't store this info... */
     avctx->coded_frame->top_field_first = 1;
 
     /*
      * Create a Ut Video instance. Since the function wants
      * an "interface name" string, pass it the name of the lib.
      */
     utv->codec = CCodec::CreateInstance(UNFCC(avctx->codec_tag), "libavcodec");
 
     /* Initialize Decoding */

     begin_ret = utv->codec->DecodeBegin(format, avctx->width, avctx->height,

                             CBGROSSWIDTH_WINDOWS, &info, sizeof(UtVideoExtra));

     /* Check to see if the decoder initlized properly */

     if (begin_ret != 0) {

         av_log(avctx, AV_LOG_ERROR,
                "Could not initialize decoder: %d\n", begin_ret);
         return -1;
     }
 

     return 0;
 }
 
 static int utvideo_decode_frame(AVCodecContext *avctx, void *data,
                                 int *data_size, AVPacket *avpkt)
 {
     UtVideoContext *utv = (UtVideoContext *)avctx->priv_data;
     AVFrame *pic = avctx->coded_frame;

     int w = avctx->width, h = avctx->height;

 
     /* Set flags */
     pic->reference = 0;
     pic->pict_type = AV_PICTURE_TYPE_I;
     pic->key_frame = 1;
 
     /* Decode the frame */
     utv->codec->DecodeFrame(utv->output, avpkt->data, true);
 
     /* Set the output data depending on the colorspace */

     switch (avctx->pix_fmt) {
     case PIX_FMT_YUV420P:
         pic->linesize[0] = w;
         pic->linesize[1] = pic->linesize[2] = w / 2;
         pic->data[0] = utv->output;
         pic->data[2] = utv->output + (w * h);
         pic->data[1] = pic->data[2] + (w * h / 4);
         break;
     case PIX_FMT_YUYV422:
         pic->linesize[0] = w * 2;
         pic->data[0] = utv->output;
         break;
     case PIX_FMT_BGR24:
     case PIX_FMT_RGB32:
         /* Make the linesize negative, since Ut Video uses bottom-up BGR */
         pic->linesize[0] = -1 * w * (avctx->pix_fmt == PIX_FMT_BGR24 ? 3 : 4);
         pic->data[0] = utv->output + utv->buf_size + pic->linesize[0];
         break;
     }

 
     *data_size = sizeof(AVFrame);
     *(AVFrame *)data = *pic;
 
     return avpkt->size;
 }
 
 static av_cold int utvideo_decode_close(AVCodecContext *avctx)
 {
     UtVideoContext *utv = (UtVideoContext *)avctx->priv_data;
 
     /* Free output */
     av_freep(&avctx->coded_frame);
     av_freep(&utv->output);
 
     /* Finish decoding and clean up the instance */
     utv->codec->DecodeEnd();
     CCodec::DeleteInstance(utv->codec);
 
     return 0;
 }
 
 AVCodec ff_libutvideo_decoder = {

     "libutvideo",

     AVMEDIA_TYPE_VIDEO,
     CODEC_ID_UTVIDEO,
     sizeof(UtVideoContext),
     utvideo_decode_init,
     NULL,
     utvideo_decode_close,
     utvideo_decode_frame,

     NULL,

     NULL,
     NULL,
     NULL,
     NULL,
     NULL_IF_CONFIG_SMALL("Ut Video"),
 };