// coupling.c draw 512 layout, check for legal coupling

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

static int legalc(int s, int legal[]);
static int checkik(int i, int k);

int main()
{
  int i, j, k, n;
  int s = 0;
  int legal[6] = {0, 0, 0, 0, 0, 0};
  int err;

  printf("coupling.c test program, running\n");
  printf("512 layout, numbers are i and j values of Jij\n");
  for(k=1; k<=8; k++)
  {
    for(j=1; j<=4; j++)
    {
      for(i=1; i<=7; i++)
      {
        printf("|%3d %3d|",s , s+4);
        s += 8;
      } 
      printf("|%3d %3d|\n",s , s+4);
      s += 9;
      s -= 64;
    }
    printf(" \n");
    s -= 4;
    s += 64;
  }
  printf(" \n");

  printf("final s=%d\n", s);

  // legal couplings
  printf("inside, general\n");
  s = 72;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 73;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 74;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 75;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 76;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 77;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 78;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 79;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  printf(" \n");
  printf("top row some not available\n");
  s = 0;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 5;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 9;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 17;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 25;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 33;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 41;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 49;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 57;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 61;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  printf(" \n");
  printf("bottom row some not available\n");
  s = 449;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 453;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 457;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 465;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 473;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 481;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 489;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 497;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 505;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  s = 509;
  n = legalc(s, legal);
  printf("s=%3d, n=%1d, legal to %3d, %3d, %3d, %3d, %3d, %3d\n",
	 s, n, legal[0], legal[1], legal[2], legal[3], legal[4], legal[5]); 
  printf(" \n");

  // user function checkik(i,k)
  err = checkik(1,2);
  if(err==0) printf("J12 coupling is legal\n");
  if(err==1) printf("J12 coupling illegal\n");
  err = checkik(507,511);
  if(err==0) printf("J507,511 coupling is legal\n");
  if(err==1) printf("J507,511 coupling illegal\n");

  printf("coupling.c finished\n");
  return 0;
} // end main

static int legalc(int s, int legal[])
{
  int localrow;
  int localcol;
  int s4, s8, s16, s64;
  int base;
  int n = 6;

  // local
  s4 = s%4;
  s8 = s%8;
  base = s - s8;
  s16 = s%16;
  s64 = s%64;
  // printf("s=%3d, s4=%3d, s8=%3d, s16=%3d, s64=%3d\n", s, s4, s8, s16, s64);
  localrow = s4;
  localcol = 1;
  if(s8>=4) localcol = 2;
  if(localcol==1)
  {
    legal[0] = base+4;
    legal[1] = base+5;
    legal[2] = base+6;
    legal[3] = base+7;
    legal[4] = base-64+s4;
    if(legal[4]<0) {legal[4] = legal[3]; n--;}
    legal[5] = base+64+s4;
    if(legal[5]>511) {legal[5] = legal[3]; n--;}
  }
  else
  {
    legal[0] = base+0;
    legal[1] = base+1;
    legal[2] = base+2;
    legal[3] = base+3;
    legal[4] = base-8+s8;
    if(s64<=7) {legal[4] = legal[3]; n--;}
    legal[5] = base+8+s8;
    if(s64>=56) {legal[5] = legal[3]; n--;}
  }  
  return n;
} // end legalc

static int checkik(int i, int k)
{
  int legal[6];
  int n;
  int j;

  n = legalc(i, legal);
  for(j=0; j<6; j++)
  {
    if(k==legal[j]) return 0;
  }
  printf("coupling %d %d not valid\n", i, k);
  return 1;
} // end checkik

// end coupling.c