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/*
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 * Miro VideoXL codec
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 * Copyright (c) 2004 Konstantin Shishkov
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 *
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 * This file is part of Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Miro VideoXL codec.
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 */
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#include "libavutil/intreadwrite.h"
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#include "avcodec.h"
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typedef struct VideoXLContext{
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    AVCodecContext *avctx;
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    AVFrame pic;
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} VideoXLContext;
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static const int xl_table[32] = {
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   0,   1,   2,   3,   4,   5,   6,   7,
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   8,   9,  12,  15,  20,  25,  34,  46,
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  64,  82,  94, 103, 108, 113, 116, 119,
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 120, 121, 122, 123, 124, 125, 126, 127};
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static int decode_frame(AVCodecContext *avctx,
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                        void *data, int *data_size,
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                        AVPacket *avpkt)
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{
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    const uint8_t *buf = avpkt->data;
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    int buf_size = avpkt->size;
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    VideoXLContext * const a = avctx->priv_data;
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    AVFrame * const p= (AVFrame*)&a->pic;
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    uint8_t *Y, *U, *V;
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    int i, j;
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    int stride;
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    uint32_t val;
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    int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0;
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    if(p->data[0])
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        avctx->release_buffer(avctx, p);
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    p->reference = 0;
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    if(avctx->get_buffer(avctx, p) < 0){
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        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
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        return -1;
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    }
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    p->pict_type= FF_I_TYPE;
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    p->key_frame= 1;
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    Y = a->pic.data[0];
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    U = a->pic.data[1];
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    V = a->pic.data[2];
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    stride = avctx->width - 4;
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    for (i = 0; i < avctx->height; i++) {
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        /* lines are stored in reversed order */
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        buf += stride;
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        for (j = 0; j < avctx->width; j += 4) {
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            /* value is stored in LE dword with word swapped */
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            val = AV_RL32(buf);
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            buf -= 4;
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            val = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16);
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            if(!j)
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                y0 = (val & 0x1F) << 2;
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            else
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                y0 = y3 + xl_table[val & 0x1F];
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            val >>= 5;
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            y1 = y0 + xl_table[val & 0x1F];
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            val >>= 5;
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            y2 = y1 + xl_table[val & 0x1F];
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            val >>= 6; /* align to word */
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            y3 = y2 + xl_table[val & 0x1F];
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            val >>= 5;
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            if(!j)
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                c0 = (val & 0x1F) << 2;
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            else
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                c0 += xl_table[val & 0x1F];
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            val >>= 5;
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            if(!j)
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                c1 = (val & 0x1F) << 2;
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            else
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                c1 += xl_table[val & 0x1F];
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            Y[j + 0] = y0 << 1;
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            Y[j + 1] = y1 << 1;
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            Y[j + 2] = y2 << 1;
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            Y[j + 3] = y3 << 1;
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            U[j >> 2] = c0 << 1;
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            V[j >> 2] = c1 << 1;
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        }
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        buf += avctx->width + 4;
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        Y += a->pic.linesize[0];
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        U += a->pic.linesize[1];
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        V += a->pic.linesize[2];
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    }
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    *data_size = sizeof(AVFrame);
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    *(AVFrame*)data = a->pic;
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    return buf_size;
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}
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static av_cold int decode_init(AVCodecContext *avctx){
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//    VideoXLContext * const a = avctx->priv_data;
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    avctx->pix_fmt= PIX_FMT_YUV411P;
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    return 0;
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}
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static av_cold int decode_end(AVCodecContext *avctx){
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    VideoXLContext * const a = avctx->priv_data;
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    AVFrame *pic = &a->pic;
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    if (pic->data[0])
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        avctx->release_buffer(avctx, pic);
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    return 0;
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}
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AVCodec ff_xl_decoder = {
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    "xl",
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    AVMEDIA_TYPE_VIDEO,
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    CODEC_ID_VIXL,
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    sizeof(VideoXLContext),
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    decode_init,
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    NULL,
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    decode_end,
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    decode_frame,
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    CODEC_CAP_DR1,
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    .long_name = NULL_IF_CONFIG_SMALL("Miro VideoXL"),
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};