/*
 *
 * Copyright (C) 2004 Konstantin Shishkov
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * IBM Ultimotion Video Decoder
 *
 */

/**
 * @file ulti.c 
 * IBM Ultimotion Video Decoder.
 */
 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "common.h"
#include "avcodec.h"

#include "ulti_cb.h"

typedef struct UltimotionDecodeContext {
    AVCodecContext *avctx;
    int width, height, blocks;
    AVFrame frame;
    uint8_t *ulti_codebook;
} UltimotionDecodeContext;

static int ulti_decode_init(AVCodecContext *avctx)
{
    UltimotionDecodeContext *s = avctx->priv_data;

    s->avctx = avctx;
    s->width = avctx->width;
    s->height = avctx->height;
    s->blocks = (s->width / 8) * (s->height / 8);
    avctx->pix_fmt = PIX_FMT_YUV410P;
    avctx->has_b_frames = 0;
    avctx->coded_frame = (AVFrame*) &s->frame;
    s->ulti_codebook = ulti_codebook;

    return 0;
}

static int block_coords[8] = // 4x4 block coords in 8x8 superblock
    { 0, 0, 0, 4, 4, 4, 4, 0};

static int angle_by_index[4] = { 0, 2, 6, 12};

/* Lookup tables for luma and chroma - used by ulti_convert_yuv() */
static uint8_t ulti_lumas[64] =
    { 0x10, 0x13, 0x17, 0x1A, 0x1E, 0x21, 0x25, 0x28,
      0x2C, 0x2F, 0x33, 0x36, 0x3A, 0x3D, 0x41, 0x44,
      0x48, 0x4B, 0x4F, 0x52, 0x56, 0x59, 0x5C, 0x60,
      0x63, 0x67, 0x6A, 0x6E, 0x71, 0x75, 0x78, 0x7C,
      0x7F, 0x83, 0x86, 0x8A, 0x8D, 0x91, 0x94, 0x98,
      0x9B, 0x9F, 0xA2, 0xA5, 0xA9, 0xAC, 0xB0, 0xB3,
      0xB7, 0xBA, 0xBE, 0xC1, 0xC5, 0xC8, 0xCC, 0xCF,
      0xD3, 0xD6, 0xDA, 0xDD, 0xE1, 0xE4, 0xE8, 0xEB};
      
static uint8_t ulti_chromas[16] =
    { 0x60, 0x67, 0x6D, 0x73, 0x7A, 0x80, 0x86, 0x8D,
      0x93, 0x99, 0xA0, 0xA6, 0xAC, 0xB3, 0xB9, 0xC0};
      
/* convert Ultimotion YUV block (sixteen 6-bit Y samples and
 two 4-bit chroma samples) into standard YUV and put it into frame */
static void ulti_convert_yuv(AVFrame *frame, int x, int y,
			     uint8_t *luma,int chroma)
{
    uint8_t *y_plane, *cr_plane, *cb_plane;
    int i;
    
    y_plane = frame->data[0] + x + y * frame->linesize[0];
    cr_plane = frame->data[1] + (x / 4) + (y / 4) * frame->linesize[1];
    cb_plane = frame->data[2] + (x / 4) + (y / 4) * frame->linesize[2];
    
    cr_plane[0] = ulti_chromas[chroma >> 4];
    
    cb_plane[0] = ulti_chromas[chroma & 0xF];

    
    for(i = 0; i < 16; i++){
	y_plane[i & 3] = ulti_lumas[luma[i]];
	if((i & 3) == 3) { //next row
	    y_plane += frame->linesize[0];
	}
    }
}

/* generate block like in MS Video1 */
static void ulti_pattern(AVFrame *frame, int x, int y,
			 int f0, int f1, int Y0, int Y1, int chroma)
{
    uint8_t Luma[16];
    int mask, i;
    for(mask = 0x80, i = 0; mask; mask >>= 1, i++) {
	if(f0 & mask)
	    Luma[i] = Y1;
	else
	    Luma[i] = Y0;
    }
    
    for(mask = 0x80, i = 8; mask; mask >>= 1, i++) {
	if(f1 & mask)
	    Luma[i] = Y1;
	else
	    Luma[i] = Y0;
    }
    
    ulti_convert_yuv(frame, x, y, Luma, chroma);
}

/* fill block with some gradient */
static void ulti_grad(AVFrame *frame, int x, int y, uint8_t *Y, int chroma, int angle)
{
    uint8_t Luma[16];
    if(angle & 8) { //reverse order
	int t;
	angle &= 0x7;
	t = Y[0];
	Y[0] = Y[3];
	Y[3] = t;
	t = Y[1];
	Y[1] = Y[2];
	Y[2] = t;
    }
    switch(angle){
    case 0:
	Luma[0]  = Y[0]; Luma[1]  = Y[1]; Luma[2]  = Y[2]; Luma[3]  = Y[3];
	Luma[4]  = Y[0]; Luma[5]  = Y[1]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
	Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[2]; Luma[11] = Y[3];
	Luma[12] = Y[0]; Luma[13] = Y[1]; Luma[14] = Y[2]; Luma[15] = Y[3];	
	break;
    case 1:
	Luma[0]  = Y[1]; Luma[1]  = Y[2]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
	Luma[4]  = Y[0]; Luma[5]  = Y[1]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
	Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[2]; Luma[11] = Y[3];
	Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[1]; Luma[15] = Y[2];	
	break;
    case 2:
	Luma[0]  = Y[1]; Luma[1]  = Y[2]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
	Luma[4]  = Y[1]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
	Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[2];
	Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[1]; Luma[15] = Y[2];	
	break;
    case 3:
	Luma[0]  = Y[2]; Luma[1]  = Y[3]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
	Luma[4]  = Y[1]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
	Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[2];
	Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[1];	
	break;
    case 4:
	Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
	Luma[4]  = Y[2]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[2];
	Luma[8]  = Y[1]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[1];
	Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[0];	
	break;
    case 5:
	Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[3]; Luma[3]  = Y[2];
	Luma[4]  = Y[3]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[1];
	Luma[8]  = Y[2]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[0];
	Luma[12] = Y[1]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[0];	
	break;
    case 6:
	Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[2]; Luma[3]  = Y[2];
	Luma[4]  = Y[3]; Luma[5]  = Y[2]; Luma[6]  = Y[1]; Luma[7]  = Y[1];
	Luma[8]  = Y[2]; Luma[9]  = Y[2]; Luma[10] = Y[1]; Luma[11] = Y[0];
	Luma[12] = Y[1]; Luma[13] = Y[1]; Luma[14] = Y[0]; Luma[15] = Y[0];	
	break;
    case 7:
	Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[2]; Luma[3]  = Y[1];
	Luma[4]  = Y[3]; Luma[5]  = Y[2]; Luma[6]  = Y[1]; Luma[7]  = Y[0];
	Luma[8]  = Y[3]; Luma[9]  = Y[2]; Luma[10] = Y[1]; Luma[11] = Y[0];
	Luma[12] = Y[2]; Luma[13] = Y[1]; Luma[14] = Y[0]; Luma[15] = Y[0];	
	break;
    default:
	Luma[0]  = Y[0]; Luma[1]  = Y[0]; Luma[2]  = Y[1]; Luma[3]  = Y[1];
	Luma[4]  = Y[0]; Luma[5]  = Y[0]; Luma[6]  = Y[1]; Luma[7]  = Y[1];
	Luma[8]  = Y[2]; Luma[9]  = Y[2]; Luma[10] = Y[3]; Luma[11] = Y[3];
	Luma[12] = Y[2]; Luma[13] = Y[2]; Luma[14] = Y[3]; Luma[15] = Y[3];	
	break;
    }
    
    ulti_convert_yuv(frame, x, y, Luma, chroma);
}

static int ulti_decode_frame(AVCodecContext *avctx, 
                             void *data, int *data_size,
                             uint8_t *buf, int buf_size)
{
    UltimotionDecodeContext *s=avctx->priv_data;
    int modifier = 0;
    int uniq = 0;
    int mode = 0;
    int blocks = 0;
    int done = 0;
    int x = 0, y = 0;
    int i;
    int skip;
    int tmp;

    if(s->frame.data[0])
        avctx->release_buffer(avctx, &s->frame);

    s->frame.reference = 1;
    s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
    if(avctx->get_buffer(avctx, &s->frame) < 0) {
        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
        return -1;
    }
    
    while(!done) {
	int idx;
	if(blocks >= s->blocks || y >= s->height)
	    break;//all blocks decoded
	
	idx = *buf++;
	if((idx & 0xF8) == 0x70) {
	    switch(idx) {
	    case 0x70: //change modifier
		modifier = *buf++;
		if(modifier>1)
		    av_log(avctx, AV_LOG_INFO, "warning: modifier must be 0 or 1, got %i\n", modifier);
		break;
	    case 0x71: // set uniq flag
		uniq = 1;
		break;
	    case 0x72: //toggle mode
		mode = !mode;
		break;
	    case 0x73: //end-of-frame
		done = 1;
		break;
	    case 0x74: //skip some blocks
		skip = *buf++;
		if ((blocks + skip) >= s->blocks)
		    break;
		blocks += skip;
		x += skip * 8;
		while(x >= s->width) {
		    x -= s->width;
		    y += 8;
		}
		break;
	    default:
		av_log(avctx, AV_LOG_INFO, "warning: unknown escape 0x%02X\n", idx);
	    }	
	} else { //handle one block
	    int code;
	    int cf;
	    int angle = 0;
	    uint8_t Y[4]; // luma samples of block
	    int tx = 0, ty = 0; //coords of subblock
	    int chroma = 0;
	    if (mode || uniq) {
		uniq = 0;
		cf = 1;
		chroma = 0;
	    } else {
		cf = 0;
		if (idx)
		    chroma = *buf++;
	    }
	    for (i = 0; i < 4; i++) { // for every subblock
		code = (idx >> (6 - i*2)) & 3; //extract 2 bits
		if(!code) //skip subblock
		    continue;
		if(cf)
		    chroma = *buf++;
		tx = x + block_coords[i * 2];
		ty = y + block_coords[(i * 2) + 1];
		switch(code) {
		case 1: 
		    tmp = *buf++;
		    
		    angle = angle_by_index[(tmp >> 6) & 0x3];
		    
		    Y[0] = tmp & 0x3F;
		    Y[1] = Y[0];
		    
		    if (angle) {
			Y[2] = Y[0]+1;
			if (Y[2] > 0x3F)
			    Y[2] = 0x3F;
			Y[3] = Y[2];			
		    } else {
			Y[2] = Y[0];
			Y[3] = Y[0];
		    }
		    break;
		    
		case 2:
		    if (modifier) { // unpack four luma samples
			tmp = (*buf++) << 16;
			tmp += (*buf++) << 8;
			tmp += *buf++;
			
			Y[0] = (tmp >> 18) & 0x3F;
			Y[1] = (tmp >> 12) & 0x3F;
			Y[2] = (tmp >> 6) & 0x3F;
			Y[3] = tmp & 0x3F;
			angle = 16;
		    } else { // retrieve luma samples from codebook
			tmp = (*buf++) << 8;
			tmp += (*buf++);
			
			angle = (tmp >> 12) & 0xF;
			tmp &= 0xFFF;
			tmp <<= 2;
			Y[0] = s->ulti_codebook[tmp];
			Y[1] = s->ulti_codebook[tmp + 1];
			Y[2] = s->ulti_codebook[tmp + 2];
			Y[3] = s->ulti_codebook[tmp + 3];
		    }
		    break;
		    
		case 3:
		    if (modifier) { // all 16 luma samples
			uint8_t Luma[16];
			
			tmp = (*buf++) << 16;
			tmp += (*buf++) << 8;
			tmp += *buf++;
			Luma[0] = (tmp >> 18) & 0x3F;
			Luma[1] = (tmp >> 12) & 0x3F;
			Luma[2] = (tmp >> 6) & 0x3F;
			Luma[3] = tmp & 0x3F;
			
			tmp = (*buf++) << 16;
			tmp += (*buf++) << 8;
			tmp += *buf++;
			Luma[4] = (tmp >> 18) & 0x3F;
			Luma[5] = (tmp >> 12) & 0x3F;
			Luma[6] = (tmp >> 6) & 0x3F;
			Luma[7] = tmp & 0x3F;
			
			tmp = (*buf++) << 16;
			tmp += (*buf++) << 8;
			tmp += *buf++;
			Luma[8] = (tmp >> 18) & 0x3F;
			Luma[9] = (tmp >> 12) & 0x3F;
			Luma[10] = (tmp >> 6) & 0x3F;
			Luma[11] = tmp & 0x3F;
			
			tmp = (*buf++) << 16;
			tmp += (*buf++) << 8;
			tmp += *buf++;
			Luma[12] = (tmp >> 18) & 0x3F;
			Luma[13] = (tmp >> 12) & 0x3F;
			Luma[14] = (tmp >> 6) & 0x3F;
			Luma[15] = tmp & 0x3F;
			
			ulti_convert_yuv(&s->frame, tx, ty, Luma, chroma);
		    } else {
			tmp = *buf++;
			if(tmp & 0x80) {
			    angle = (tmp >> 4) & 0x7;
			    tmp = (tmp << 8) + *buf++;
			    Y[0] = (tmp >> 6) & 0x3F;
			    Y[1] = tmp & 0x3F;
			    Y[2] = (*buf++) & 0x3F;
			    Y[3] = (*buf++) & 0x3F;
			    ulti_grad(&s->frame, tx, ty, Y, chroma, angle); //draw block
			} else { // some patterns
			    int f0, f1;
			    f0 = *buf++;
			    f1 = tmp;
			    Y[0] = (*buf++) & 0x3F;
			    Y[1] = (*buf++) & 0x3F;
			    ulti_pattern(&s->frame, tx, ty, f1, f0, Y[0], Y[1], chroma);
			}
		    }
		    break;
		}
		if(code != 3)
		    ulti_grad(&s->frame, tx, ty, Y, chroma, angle); // draw block
	    }
	    blocks++;
    	    x += 8;
	    if(x >= s->width) {
		x = 0;
		y += 8;
	    }
	}
    }
    
    *data_size=sizeof(AVFrame);
    *(AVFrame*)data= s->frame;

    return buf_size;
}

static int ulti_decode_end(AVCodecContext *avctx)
{
/*    UltimotionDecodeContext *s = avctx->priv_data;*/

    return 0;
}

AVCodec ulti_decoder = {
    "ultimotion",
    CODEC_TYPE_VIDEO,
    CODEC_ID_ULTI,
    sizeof(UltimotionDecodeContext),
    ulti_decode_init,
    NULL,
    ulti_decode_end,
    ulti_decode_frame,
    CODEC_CAP_DR1,
    NULL
};

