1 /*	@(#)one.c	8.1 (Berkeley) 5/31/93			*/
2 /*	$NetBSD: one.c,v 1.9 2012/10/13 19:19:39 dholland Exp $	*/
3 
4 /*
5  * Copyright (c) 1980, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "back.h"
34 
35 static int checkd(struct move *, int);
36 static int last(void);
37 
38 int
39 makmove(struct move *mm, int i)
40 {
41 	int     n, d;
42 	int     max;
43 
44 	d = mm->d0;
45 	n = abs(mm->g[i] - mm->p[i]);
46 	max = (*offptr < 0 ? 7 : last());
47 	if (board[mm->p[i]] * cturn <= 0)
48 		return (checkd(mm, d) + 2);
49 	if (mm->g[i] != home && board[mm->g[i]] * cturn < -1)
50 		return (checkd(mm, d) + 3);
51 	if (i || mm->D0 == mm->D1) {
52 		if (n == max ? mm->D1 < n : mm->D1 != n)
53 			return (checkd(mm, d) + 1);
54 	} else {
55 		if (n == max ? mm->D0 < n && mm->D1 < n : mm->D0 != n && mm->D1 != n)
56 			return (checkd(mm, d) + 1);
57 		if (n == max ? mm->D0 < n : mm->D0 != n) {
58 			if (mm->d0)
59 				return (checkd(mm, d) + 1);
60 			mswap(mm);
61 		}
62 	}
63 	if (mm->g[i] == home && *offptr < 0)
64 		return (checkd(mm, d) + 4);
65 	mm->h[i] = 0;
66 	board[mm->p[i]] -= cturn;
67 	if (mm->g[i] != home) {
68 		if (board[mm->g[i]] == -cturn) {
69 			board[home] -= cturn;
70 			board[mm->g[i]] = 0;
71 			mm->h[i] = 1;
72 			if (abs(bar - mm->g[i]) < 7) {
73 				(*inopp)--;
74 				if (*offopp >= 0)
75 					*offopp -= 15;
76 			}
77 		}
78 		board[mm->g[i]] += cturn;
79 		if (abs(home - mm->g[i]) < 7 && abs(home - mm->p[i]) > 6) {
80 			(*inptr)++;
81 			if (*inptr + *offptr == 0)
82 				*offptr += 15;
83 		}
84 	} else {
85 		(*offptr)++;
86 		(*inptr)--;
87 	}
88 	return (0);
89 }
90 
91 void
92 moverr(struct move *mm, int i)
93 {
94 	int     j;
95 
96 	if (tflag)
97 		curmove(20, 0);
98 	else
99 		writec('\n');
100 	writel("Error:  ");
101 	for (j = 0; j <= i; j++) {
102 		wrint(mm->p[j]);
103 		writec('-');
104 		wrint(mm->g[j]);
105 		if (j < i)
106 			writec(',');
107 	}
108 	writel("... ");
109 	movback(mm, i);
110 }
111 
112 
113 static int
114 checkd(struct move *mm, int d)
115 {
116 	if (mm->d0 != d)
117 		mswap(mm);
118 	return (0);
119 }
120 
121 static int
122 last(void)
123 {
124 	int     i;
125 
126 	for (i = home - 6 * cturn; i != home; i += cturn)
127 		if (board[i] * cturn > 0)
128 			return (abs(home - i));
129 	return (-1);
130 }
131 
132 void
133 movback(struct move *mm, int i)
134 {
135 	int     j;
136 
137 	for (j = i - 1; j >= 0; j--)
138 		backone(mm, j);
139 }
140 
141 void
142 backone(struct move *mm, int i)
143 {
144 	board[mm->p[i]] += cturn;
145 	if (mm->g[i] != home) {
146 		board[mm->g[i]] -= cturn;
147 		if (abs(mm->g[i] - home) < 7 && abs(mm->p[i] - home) > 6) {
148 			(*inptr)--;
149 			if (*inptr + *offptr < 15 && *offptr >= 0)
150 				*offptr -= 15;
151 		}
152 	} else {
153 		(*offptr)--;
154 		(*inptr)++;
155 	}
156 	if (mm->h[i]) {
157 		board[home] += cturn;
158 		board[mm->g[i]] = -cturn;
159 		if (abs(bar - mm->g[i]) < 7) {
160 			(*inopp)++;
161 			if (*inopp + *offopp == 0)
162 				*offopp += 15;
163 		}
164 	}
165 }
166