/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include        <ctype.h>
#include        "tdef.h"
#include "ext.h"
#define HY_BIT  0200    /* stuff in here only works for ascii */

/*
 * troff8.c
 *
 * hyphenation
 */

char    hbuf[NHEX];
char    *nexth = hbuf;
tchar   *hyend;
#define THRESH 160 /*digram goodness threshold*/
int     thresh = THRESH;

int
hyphen(wp)
        tchar *wp;
{
        int     j;
        tchar *i;

        i = wp;
        while (punct(cbits(*i++)))
                ;
        if (!alph(cbits(*--i)))
                return (0);
        wdstart = i++;
        while (alph(cbits(*i++)))
                ;
        hyend = wdend = --i - 1;
        while (punct(cbits(*i++)))
                ;
        if (*--i)
                return (0);
        if ((wdend - wdstart - 4) < 0)
                return (0);
        hyp = hyptr;
        *hyp = 0;
        hyoff = 2;
        if (!exword() && !suffix())
                digram();
        *hyp++ = 0;
        if (*hyptr)
                for (j = 1; j; ) {
                        j = 0;
                        for (hyp = hyptr + 1; *hyp != 0; hyp++) {
                                if (*(hyp - 1) > *hyp) {
                                        j++;
                                        i = *hyp;
                                        *hyp = *(hyp - 1);
                                        *(hyp - 1) = i;
                                }
                        }
                }

        return (0);
}


int
punct(int i)
{
        if (!i || alph(i))
                return(0);
        else
                return(1);
}


int
alph(int i)
{
        if (i >= 'a' && i <= 'z' || i >= 'A' && i <= 'Z')
                return(1);
        else
                return(0);
}


int
caseht()
{
        thresh = THRESH;
        if (skip())
                return (0);
        noscale++;
        thresh = atoi();
        noscale = 0;

        return (0);
}


int
casehw()
{
        int     i, k;
        char    *j;
        tchar t;

        k = 0;
        while (!skip()) {
                if ((j = nexth) >= (hbuf + NHEX - 2))
                        goto full;
                for (; ; ) {
                        if (ismot(t = getch()))
                                continue;
                        i = cbits(t);
                        if (i == ' ' || i == '\n') {
                                *j++ = 0;
                                nexth = j;
                                *j = 0;
                                if (i == ' ')
                                        break;
                                else
                                        return (0);
                        }
                        if (i == '-') {
                                k = HY_BIT;
                                continue;
                        }
                        *j++ = maplow(i) | k;
                        k = 0;
                        if (j >= (hbuf + NHEX - 2))
                                goto full;
                }
        }
        return (0);
full:
        errprint(gettext("exception word list full."));
        *nexth = 0;

        return (0);
}


int
exword()
{
        tchar *w;
        char    *e;
        char    *save;

        e = hbuf;
        while (1) {
                save = e;
                if (*e == 0)
                        return(0);
                w = wdstart;
                while (*e && w <= hyend && (*e & 0177) == maplow(cbits(*w))) {
                        e++;
                        w++;
                };
                if (!*e) {
                        if (w-1 == hyend || (w == wdend && maplow(cbits(*w)) == 's')) {
                                w = wdstart;
                                for (e = save; *e; e++) {
                                        if (*e & HY_BIT)
                                                *hyp++ = w;
                                        if (hyp > (hyptr + NHYP - 1))
                                                hyp = hyptr + NHYP - 1;
                                        w++;
                                }
                                return(1);
                        } else {
                                e++;
                                continue;
                        }
                } else
                        while (*e++)
                                ;
        }

        return (0);
}


int
suffix()
{
        tchar *w;
        char    *s, *s0;
        tchar i;
        extern char     *suftab[];
        extern tchar *chkvow();

again:
        if (!alph(cbits(i = cbits(*hyend))))
                return(0);
        if (i < 'a')
                i -= 'A' - 'a';
        if ((s0 = suftab[i-'a']) == 0)
                return(0);
        for (; ; ) {
                if ((i = *s0 & 017) == 0)
                        return(0);
                s = s0 + i - 1;
                w = hyend - 1;
                while (s > s0 && w >= wdstart && (*s & 0177) == maplow(cbits(*w))) {
                        s--;
                        w--;
                }
                if (s == s0)
                        break;
                s0 += i;
        }
        s = s0 + i - 1;
        w = hyend;
        if (*s0 & HY_BIT)
                goto mark;
        while (s > s0) {
                w--;
                if (*s-- & HY_BIT) {
mark:
                        hyend = w - 1;
                        if (*s0 & 0100)
                                continue;
                        if (!chkvow(w))
                                return(0);
                        *hyp++ = w;
                }
        }
        if (*s0 & 040)
                return(0);
        if (exword())
                return(1);
        goto again;
}


int
maplow(i)
int     i;
{
        if (ischar(i) && isupper(i))
                i = tolower(i);
        return(i);
}


int
vowel(i)
int     i;
{
        switch (maplow(i)) {
        case 'a':
        case 'e':
        case 'i':
        case 'o':
        case 'u':
        case 'y':
                return(1);
        default:
                return(0);
        }
}


tchar *chkvow(w)
tchar *w;
{
        while (--w >= wdstart)
                if (vowel(cbits(*w)))
                        return(w);
        return(0);
}


int
digram()
{
        tchar *w;
        int     val;
        tchar * nhyend, *maxw;
        int     maxval;
        extern char     bxh[26][13], bxxh[26][13], xxh[26][13], xhx[26][13], hxx[26][13];

again:
        if (!(w = chkvow(hyend + 1)))
                return (0);
        hyend = w;
        if (!(w = chkvow(hyend)))
                return (0);
        nhyend = w;
        maxval = 0;
        w--;
        while ((++w < hyend) && (w < (wdend - 1))) {
                val = 1;
                if (w == wdstart)
                        val *= dilook('a', cbits(*w), bxh);
                else if (w == wdstart + 1)
                        val *= dilook(cbits(*(w-1)), cbits(*w), bxxh);
                else
                        val *= dilook(cbits(*(w-1)), cbits(*w), xxh);
                val *= dilook(cbits(*w), cbits(*(w+1)), xhx);
                val *= dilook(cbits(*(w+1)), cbits(*(w+2)), hxx);
                if (val > maxval) {
                        maxval = val;
                        maxw = w + 1;
                }
        }
        hyend = nhyend;
        if (maxval > thresh)
                *hyp++ = maxw;
        goto again;
}


int
dilook(a, b, t)
int     a, b;
char    t[26][13];
{
        int     i, j;

        i = t[maplow(a)-'a'][(j = maplow(b)-'a')/2];
        if (!(j & 01))
                i >>= 4;
        return(i & 017);
}