/*       CCCC H   H EEEEE  SSSS  SSSS        CCCC 
**      C     H   H E     S     S           C     
**      C     HHHHH EEEE   SSS   SSS        C     
**      C     H   H E         S     S  ..   C     
**       CCCC H   H EEEEE SSSS  SSSS   ..    CCCC 
**
**      c h e s s . c           DAHarrod
**
**      test of C compiler on various platforms
**      ... draws a chessboard
**
**      29-jun-76       FORTRAN - XDS Sigma 9 - original version
**      27-oct-79       FORTRAN - PDP 11/70
**      08-jul-82       C       - VAX 780
**      01-apr-83       Pascal  - IBM PC
**      04-dec-83       C       - DEC Rainbow (Aztec CII)
**      22-dec-83               - modified to read data from a file
**      30-may-84       C       - SAGE-IV (DRI CP/M-68K)
**      09-sep-84       C       - DEC Rainbow (CI-C86)
**      23-aug-93       C       - Microsoft (ANSI) Visual C++
**      01-aug-95       C       - changed default board
**                     
**      usage:  A>CHESS filename
**
**      reads data from named file to display chessboard - see files
**      CHESS.DAT and CHESS2.DAT for examples
*/

#include <stdio.h>
#include <stdlib.h>

#define PERIOD  '.'
#define BLANK   ' '
#define BLACK   'B'
#define WHITE   'W'

FILE    *in_fcb;
char    board[64][80], pcolor, sqcolor;
long    buffer,
        mask[7] = { 0, 0xe9e88, 0xe9e9e, 0x9db99, 0xe9ea9, 0x699a5, 0x9aca9 };
int     bcol, brow, col, re, row, ua,
        sq[8][8] = {   /* "SHANNON'S SACRIFICE" - SCIENTIFIC AMERICAN, FEB'50 */
                {  0,  0,  0, -4,  0,  0, -6, -4 },     /*   . * .-R . *-K-R  */
                { -1, -1, -1,  0,  0, -3,  0, -1 },     /*  -P-P-P . *-N *-P  */
                {  0,  0,  0,  0,  0,  0,  0,  2 },     /*   . * . * . * . B  */
                {  0,  0,  0,  0,  0, -5,  0,  3 },     /*   * . * . *-Q * N  */
                {  0, -2, -1,  0,  0,  0,  0,  0 },     /*   .-B-P * . * . *  */
                {  0,  0,  1, -1,  0,  0,  0,  0 },     /*   * . P-P * . * .  */
                {  1,  1,  0,  0,  4,  1,  1,  1 },     /*   P P . * R P P P  */
                {  4,  0,  0,  5,  0,  0,  6,  0 }      /*   R . * Q * . K .  */
                };      /* default values */

void main( int argc, char **argv )
{
/*  read chessboard data from named file
**  ... or use default if no file named
*/
    if ((in_fcb = fopen(argv[1],"r")) == NULL) {        /* barf on open error */
        if (argc>1)
            fprintf(stderr, "\007\nCannot open data file '%s'\007\n", argv[1]);
    }
    else {
        for (ua=0 ; ua<8 ; ua++)                        /* for each row ... */
            for (re=0 ; re<8 ; re++)                    /* for each column ... */
                fscanf(in_fcb, "%d", &sq[ua][re]);      /* ... get value */
        fclose(in_fcb);
    }
/*
**  fill the board with periods & spaces
*/
    for (re=0 ; re<8 ; re++)
        for (ua=0 ; ua<8 ; ua++) {
            sqcolor = (((ua+re)%2)==0 ? BLANK : PERIOD);
            for (row=0 ; row<8 ; row++) {
                brow = ua*8 + row;
                for (col=0 ; col<10 ; col++) {
                    bcol = re*10 + col;
                    board[brow][bcol] = sqcolor;
                }
            }
        }
/*
**  for each sq[ua][re] determine the kind of piece ('mask'),
**  the color of the piece ('pcolor'), and the color of the
**  square ('sqcolor').
*/
    for (ua=0 ; ua<8 ; ua++)
        for (re=0 ; re<8 ; re++) {
            buffer = mask[(sq[ua][re]<0 ? abs(sq[ua][re]) : sq[ua][re])];
            pcolor = (sq[ua][re]<0 ? BLACK : WHITE);
            sqcolor = (((ua+re)%2)==0 ? BLANK : PERIOD);
/*
**  now strip the 'buffer' a bit at a time, and using each
**  bit as a guide, move the 'sqcolor' or 'pcolor' into the
**  corresponding position in the 4 x 5 matrix for the sq[ua][re].
*/
            for (row=6 ; row>1 ; row--) {
                brow = ua*8 + row;
                for (col=6 ; col>2 ; col--) {
                    bcol = re*10 + col;
                    board[brow][bcol] = (((int)buffer%2)!=0 ? pcolor : sqcolor);
                    buffer /= 2;
                }
            }
        }
/*
**  now that you've got it, put it on paper
*/
    for (row=0 ; row<64 ; row++) {
        if ((row%8)!=0) {
            for (col=0 ; col<80 ; col++)
                printf("%c",board[row][col]);
            printf("\n");
        }
    }
}