#include <stdio.h>
#include <ctype.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/time.h>

#include "pline.h"

#include "dice.h"

void initrandom(void)
{
 struct timeval tv;

 gettimeofday(&tv,(struct timezone *)0);
 srandom(tv.tv_sec^tv.tv_usec^getpid()^getuid()^gethostid());
}

int rnd(int n)
{
 return(random()%n);
}

int onein(int n)
{
 return((n>1)?!rnd(n):1);
}

static int d(int n, int sides)
{
 int total;

 total = 0;
 for (;n>0;n--)
  { total += 1 + (random() % sides);
  }
 return(total);
}

int roll(const char *str)
{
 int total;
 int ndice;
 int nsides;
 const char *cp;
 int neg;

 cp = str;
 neg = 0;
 total = 0;
 while (1)
  { if (isdigit((unsigned char)*cp))
     { ndice = 0;
       while (isdigit((unsigned char)*cp))
	{ ndice = (10 * ndice) + (*cp - '0');
	  cp ++;
	}
     }
    else if (*cp == 'd')
     { ndice = 1;
     }
    if (*cp == 'd')
     { cp ++;
       nsides = 0;
       while (isdigit((unsigned char)*cp))
	{ nsides = (10 * nsides) + (*cp - '0');
	  cp ++;
	}
       if (neg)
	{ total -= d(ndice,nsides);
	}
       else
	{ total += d(ndice,nsides);
	}
     }
    else
     { if (neg)
	{ total -= ndice;
	}
       else
	{ total += ndice;
	}
     }
    neg = 0;
    if (*cp == '+')
     { cp ++;
     }
    else if (*cp == '-')
     { neg = 1;
       cp ++;
     }
    else if (*cp == '\0')
     { break;
     }
    else
     { panic("Bad dice spec `%s' to roll()",str);
     }
  }
 return(total);
}