/*
                GNU GO - the game of Go (Wei-Chi)
                Version 1.1   last revised 3-1-89
           Copyright (C) Free Software Foundation, Inc.
                      written by Man L. Li
                      modified by Wayne Iba
                    documented by Bob Webber

     Feb 1990	Edited by S.Hawtin to work under NorthC on the Amiga

*/
/*
This program 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 1.

This program 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 in file COPYING for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

Please report any bug/fix, modification, suggestion to

mail address:   Man L. Li
                Dept. of Computer Science
                University of Houston
                4800 Calhoun Road
                Houston, TX 77004

e-mail address: manli@cs.uh.edu         (Internet)
                coscgbn@uhvax1.bitnet   (BITNET)
                70070,404               (CompuServe)
*/

#include <stdio.h>

#define EMPTY 0

extern unsigned char p[19][19];
extern int mymove, umove;
extern int opn[9];

/* AMIGA moved statics outside function */
static int cnd, mtype;  /* game tree node number, move type */

findpatn(i, j, val)
/* find pattern to match for next move */
int *i, *j, *val;
{
 int m, n;
 int ti, tj, tval;
/* mtype = 0, basic; 1, inverted; 2, reflected; 3, inverted & reflected */

/* open game then occupy corners */
 if (opn[4])   /* continue last move */
   {
    opn[4] = 0;  /* clear flag */
    if (opening(i, j, &cnd, mtype)) opn[4] = 1; /* more move then reset flag */
    if (p[*i][*j] == EMPTY)  /* valid move */
      {
       *val = 80;
       return 1;
     }
    else
      opn[4] = 0;
  }

 if (opn[0])   /* Northwest corner */
   {
    opn[0] = 0;  /* clear flag */
    if (openregion(0, 0, 5, 5))
      {
       cnd = 0;
       mtype = 0;
       opening(i, j, &cnd, mtype);  /* get new node for next move */
       if (opening(i, j, &cnd, mtype)) opn[4] = 1;
       *val = 80;
       return 1;
     }
 }

 if (opn[1])   /* Southwest corner */
   {
    opn[1] = 0;
    if (openregion(13, 0, 18, 5))
      {
       cnd = 0;
       mtype = 1;
       opening(i, j, &cnd, mtype);  /* get new node for next move */
       if (opening(i, j, &cnd, mtype)) opn[4] = 1;
       *val = 80;
       return 1;
     }
  }

 if (opn[2])   /* Northeast corner */
   {
    opn[2] = 0;
    if (openregion(0, 13, 5, 18))
      {
       cnd = 0;
       mtype = 2;
       opening(i, j, &cnd, mtype);  /* get new node for next move */
       if (opening(i, j, &cnd, mtype)) opn[4] = 1;
       *val = 80;
       return 1;
     }
  }

 if (opn[3])   /* Northeast corner */
   {
    opn[3] = 0;
    if (openregion(13, 13, 18, 18))
      {
       cnd = 0;
       mtype = 3;
       opening(i, j, &cnd, mtype);  /* get new node for next move */
       if (opening(i, j, &cnd, mtype)) opn[4] = 1;
       *val = 80;
       return 1;
     }
  }

/* occupy edges */
 if (opn[5])   /* North edge */
   {
    opn[5] = 0;
    if (openregion(0, 6, 4, 11))
      {
       *i = 3;
       *j = 9;
       *val = 80;
       return 1;
     }
  }

 if (opn[6])   /* South edge */
   {
    opn[6] = 0;
    if (openregion(18, 6, 14, 11))
      {
       *i = 15;
       *j = 9;
       *val = 80;
       return 1;
     }
  }

 if (opn[7])   /* West edge */
   {
    opn[7] = 0;
    if (openregion(6, 0, 11, 4))
      {
       *i = 9;
       *j = 3;
       *val = 80;
       return 1;
     }
  }

 if (opn[8])   /* East edge */
   {
    opn[8] = 0;
    if (openregion(6, 18, 11, 14))
      {
       *i = 9;
       *j = 15;
       *val = 80;
       return 1;
     }
  }

 *i = -1;
 *j = -1;
 *val = -1;

/* find local pattern */
 for (m = 0; m < 19; m++)
   for (n = 0; n < 19; n++)
     if ((p[m][n] == mymove) &&
         (matchpat(m, n, &ti, &tj, &tval) && (tval > *val)))
       {
        *val = tval;
        *i = ti;
        *j = tj;
      }
 if (*val > 0)  /* pattern found */
    return 1;
 else  /* no match found */
    return 0;
}  /* end findpatn */