/* -*-c,save-*- */
/*
 * pokev.c - poker evaluation functions
 * Robert Heller. Created: Sun Mar 9, 1986 17:59:57.14
 * Last Mod: 
 * 
 * (c) Copyright 1986 by Robert Heller
 *     All Rights Reserved
 * 
 * 
 */
#include <stdio.h>

#define LOCAL static

/* #define DEBUG /* debugging */

#ifdef DEBUG
#define LOCAL /* static */
#endif

LOCAL float POKEV_A[10];

#define A(INDX) POKEV_A[(INDX)+1]

pok_ini()
{
#ifdef DEBUG
    register int i;
#endif

    A(-1) = 0.0;
    A(0) = 0.501;
    A(1) = 0.924;
    A(2) = 0.971;
    A(3) = 0.9924;
    A(4) = 0.9963;
    A(5) = 0.9983;
    A(6) = 0.99974;
    A(7) = 0.999985;
    A(8) = 1.0;

#ifdef DEBUG
    for (i=(-1);i<9;i++) {
	printf("POKEV[%d] = %f\n",i,A(i));
	}
#endif
    }
LOCAL char VALS[6];
LOCAL float pr(l,prefix)
register int l;
register char *prefix;
{
    register int combs;
    float pow13();
    register float fraction,result;

#ifdef DEBUG
    printf("***In pr(): l=%d,prefix=%s,VALS=%s\n",l,prefix,VALS);
#endif
    combs = comb(13,strlen(VALS));
    fraction = ((float) (base10(prefix,13) * combs + decomb(VALS))) / 
	       (pow13(strlen(prefix)) * ((float) combs));
#ifdef DEBUG
    printf("***         fraction=%f\n",fraction);
#endif
    result = A(l-1) + ((A(l)-A(l-1)) * fraction);
#ifdef DEBUG
    printf("***pr() returns %f\n",result);
#endif
    return(result);
    }
LOCAL float pow13(ipow)
register int ipow;
{
    register float result;
    register int iresult;

    iresult = 1;
#ifdef DEBUG
    printf("***13^%d=",ipow);
#endif
    while (ipow-- > 0) iresult *= 13;
    result = (float) iresult;
#ifdef DEBUG
    printf("%f\n",result);
#endif
    return(result);
    }
LOCAL comb(n,m)
register int n,m;
{
    register int k,result,diff;

#ifdef DEBUG
    printf("***comb(%d,%d)\n",n,m);
#endif
    if (m == 0) result = 1;
    else result = comb(n-1,m-1) * n / m;  
#ifdef DEBUG
    printf("***comb returns %d\n",result);
#endif
    return(result);
    }
LOCAL decomb(s)
register char *s;
{
    register int k,t,result;

#ifdef DEBUG
    printf("***decomb(%s)\n",s);
#endif
    result = 0;
    while (*s != '\0') {
	k = *s-'A';
	s++;
	result += comb(k,strlen(s)+1);
	}
#ifdef DEBUG
    printf("***decomb returns %d\n",result);
#endif
    return(result);
    }
LOCAL base10(n,b)
register char *n;
register int b;
{
    register int t,result;

#ifdef DEBUG
    printf("***base10(%s,%d) = ",n,b);
#endif
    result = 0;
    while (*n != '\0') {
	t = *n - 'A'; n++;
	result = (result * b) + t;
	}
#ifdef DEBUG
    printf("%d\n",result);
#endif
    return(result);
    }
LOCAL char *STRAIGHT_SEQ = "MLKJIHGFEDCBAM";
float pokev(h)
register char *h;
{
    char SUITS[6],temp[3];
#ifdef DEBUG
    char scratch[20];
#endif
    int rchar();
    float pr();
    register char v,w,*p;
    register int i;
    char *index(),*ispair(),*istrips(),*isfours(),*isflush();

#ifdef DEBUG
    display(h,scratch);
    printf("***In pokev(): h = %s\n",scratch);
#endif
    vals(h,VALS);
    qsort(VALS,strlen(VALS),sizeof(char),rchar);
    suits(h,SUITS);
    if (isstraight(VALS)) {
	if (isflush(SUITS) != NULL) return(pr(8,""));
	else return(pr(4,""));
	}
    if (isflush(SUITS) != NULL) return(pr(5,""));
    else if (ispair(VALS) == NULL) return(pr(0,""));
    else {
	p = isfours(VALS);
	if (p != NULL) {
	    temp[0] = v = *p; temp[1] = '\0';
	    for (i=0;i<4;i++) {
		p = index(VALS,v);
		strcpy(p,p+1);
		}
	    return(pr(7,temp));
	    }
	p = istrips(VALS);
	if (p != NULL) {
	    w = v = *p; temp[0] = w; temp[1] = '\0'; temp[2] = '\0';
	    for (i=0;i<3;i++) {
		p = index(VALS,v);
		strcpy(p,p+1);
		}
	    p = ispair(VALS);
	    if (p == NULL) return(pr(3,temp));
	    else {
		temp[1] = v = *p;
		for (i=0;i<2;i++) {
		    p = index(VALS,v);
		    strcpy(p,p+1);
		    }
		return(pr(6,temp));
		}
	    
	    }
	else {
	    p = ispair(VALS);
	    temp[1] = temp[2] = '\0';
	    if (p != NULL) {
		temp[0] = w = *p;
		for (i=0;i<2;i++) {
		    p = index(VALS,w);
		    strcpy(p,p+1);
		    }
		}
	    p = ispair(VALS);
	    if (p == NULL) return(pr(1,temp));
	    else {
		v = *p;
		for (i=0;i<2;i++) {
		    p = index(VALS,v);
		    strcpy(p,p+1);
		    }
		temp[1] = v;
		return(pr(2,temp));
		}
	    }
	}
    }
LOCAL rchar(a,b)
register char *a,*b;
{
    return(*b-*a);
    }
LOCAL isstraight(str)
register char *str;
{
    char *index(),temp[8];
    register char *p1,*p2;

    for (p1 = str;p1 != '\0'; p1++) {
	p2 = index(STRAIGHT_SEQ,*p1);
	if (p2 != NULL) break;
	}
    if (p2 != NULL && strncmp(p2,p1,strlen(p1)) == 0) return(TRUE);
    strcpy(temp,str+1);
    p1 = temp+strlen(temp);
    *p1++ = *str;
    *p1 = '\0';
    for (p1 = temp;p1 != '\0'; p1++) {
	p2 = index(STRAIGHT_SEQ,*p1);
	if (p2 != NULL) break;
	}
    if (p2 != NULL && strncmp(p2,p1,strlen(p1)) == 0) return(TRUE);
    return(FALSE);
    }
LOCAL char *ispair(str)
register char *str;
{
    char *index();
    register char *p1,*p2;

    for (p1 = str; *p1 != '\0'; p1++) {
	p2 = index(p1+1,*p1);
	if (p2 != NULL) break;
	}
    return(p2);
    }
LOCAL char *istrips(str)
register char *str;
{
    char *ispair(),*index();
    register char *p1,*p2;

    for (p1 = str;*p1 != '\0'; p1++) {
	p2 = ispair(p1);
	if (p2 != NULL && ((p2 = index(p2+1,*p2)) != NULL)) break;
	}
    return(p2);
    }
LOCAL char *isfours(str)
register char *str;
{
    char *istrips(),*index();
    register char *p1,*p2;

    for (p1 = str;*p1 != '\0'; p1++) {
	p2 = istrips(p1);
	if (p2 != NULL && ((p2 = index(p2+1,*p2)) != NULL)) break;
	}
    return(p2);
    }
LOCAL char *isflush(str)
register char *str;
{
    char *isfours(),*index();
    register char *p1,*p2;

    for (p1 = str;*p1 != '\0'; p1++) {
	p2 = isfours(p1);
	if (p2 != NULL && ((p2 = index(p2+1,*p2)) != NULL)) break;
	}
    return(p2);
    }