/*
  * 012v decoder
  *
  * Copyright (C) 2012 Carl Eugen Hoyos
  *
  * 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 "internal.h"
 #include "libavutil/intreadwrite.h"
 
 static av_cold int zero12v_decode_init(AVCodecContext *avctx)
 {
     avctx->pix_fmt             = PIX_FMT_YUV422P16;
     avctx->bits_per_raw_sample = 10;
 
     avctx->coded_frame = avcodec_alloc_frame();
     if (!avctx->coded_frame)
         return AVERROR(ENOMEM);
 
     if (avctx->codec_tag == MKTAG('a', '1', '2', 'v'))
         av_log_ask_for_sample(avctx, "Samples with actual transparency needed\n");
 
     avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
     avctx->coded_frame->key_frame = 1;
     return 0;
 }
 
 static int zero12v_decode_frame(AVCodecContext *avctx, void *data,
                                 int *got_frame, AVPacket *avpkt)
 {

     int line = 0, ret;

     const int width = avctx->width;
     AVFrame *pic = avctx->coded_frame;
     uint16_t *y, *u, *v;
     const uint8_t *line_end, *src = avpkt->data;
     int stride = avctx->width * 8 / 3;
 
     if (pic->data[0])
         avctx->release_buffer(avctx, pic);
 
     if (width == 1) {
         av_log(avctx, AV_LOG_ERROR, "Width 1 not supported.\n");
         return AVERROR_INVALIDDATA;
     }
     if (avpkt->size < avctx->height * stride) {
         av_log(avctx, AV_LOG_ERROR, "Packet too small: %d instead of %d\n",
                avpkt->size, avctx->height * stride);
         return AVERROR_INVALIDDATA;
     }
 
     pic->reference = 0;

     if ((ret = ff_get_buffer(avctx, pic)) < 0)
         return ret;

 
     y = (uint16_t *)pic->data[0];
     u = (uint16_t *)pic->data[1];
     v = (uint16_t *)pic->data[2];
     line_end = avpkt->data + stride;
 
     while (line++ < avctx->height) {
         while (1) {
             uint32_t t = AV_RL32(src);
             src += 4;
             *u++ = t <<  6 & 0xFFC0;
             *y++ = t >>  4 & 0xFFC0;
             *v++ = t >> 14 & 0xFFC0;
 
             if (src >= line_end - 1) {
                 *y = 0x80;
                 src++;
                 line_end += stride;
                 y = (uint16_t *)(pic->data[0] + line * pic->linesize[0]);
                 u = (uint16_t *)(pic->data[1] + line * pic->linesize[1]);
                 v = (uint16_t *)(pic->data[2] + line * pic->linesize[2]);
                 break;
             }
 
             t = AV_RL32(src);
             src += 4;
             *y++ = t <<  6 & 0xFFC0;
             *u++ = t >>  4 & 0xFFC0;
             *y++ = t >> 14 & 0xFFC0;
             if (src >= line_end - 2) {
                 if (!(width & 1)) {
                     *y = 0x80;
                     src += 2;
                 }
                 line_end += stride;
                 y = (uint16_t *)(pic->data[0] + line * pic->linesize[0]);
                 u = (uint16_t *)(pic->data[1] + line * pic->linesize[1]);
                 v = (uint16_t *)(pic->data[2] + line * pic->linesize[2]);
                 break;
             }
 
             t = AV_RL32(src);
             src += 4;
             *v++ = t <<  6 & 0xFFC0;
             *y++ = t >>  4 & 0xFFC0;
             *u++ = t >> 14 & 0xFFC0;
 
             if (src >= line_end - 1) {
                 *y = 0x80;
                 src++;
                 line_end += stride;
                 y = (uint16_t *)(pic->data[0] + line * pic->linesize[0]);
                 u = (uint16_t *)(pic->data[1] + line * pic->linesize[1]);
                 v = (uint16_t *)(pic->data[2] + line * pic->linesize[2]);
                 break;
             }
 
             t = AV_RL32(src);
             src += 4;
             *y++ = t <<  6 & 0xFFC0;
             *v++ = t >>  4 & 0xFFC0;
             *y++ = t >> 14 & 0xFFC0;
 
             if (src >= line_end - 2) {
                 if (width & 1) {
                     *y = 0x80;
                     src += 2;
                 }
                 line_end += stride;
                 y = (uint16_t *)(pic->data[0] + line * pic->linesize[0]);
                 u = (uint16_t *)(pic->data[1] + line * pic->linesize[1]);
                 v = (uint16_t *)(pic->data[2] + line * pic->linesize[2]);
                 break;
             }
         }
     }
 
     *got_frame = 1;
     *(AVFrame*)data= *avctx->coded_frame;
 
     return avpkt->size;
 }
 
 static av_cold int zero12v_decode_close(AVCodecContext *avctx)
 {
     AVFrame *pic = avctx->coded_frame;
     if (pic->data[0])
         avctx->release_buffer(avctx, pic);
     av_freep(&avctx->coded_frame);
 
     return 0;
 }
 
 AVCodec ff_zero12v_decoder = {
     .name           = "012v",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_012V,
     .init           = zero12v_decode_init,
     .close          = zero12v_decode_close,
     .decode         = zero12v_decode_frame,
     .capabilities   = CODEC_CAP_DR1,
     .long_name      = NULL_IF_CONFIG_SMALL("Uncompressed 4:2:2 10-bit"),
 };