/*      $OpenBSD: v_ulcase.c,v 1.10 2016/05/27 09:18:12 martijn Exp $   */

/*-
 * Copyright (c) 1992, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1992, 1993, 1994, 1995, 1996
 *      Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 */

#include "config.h"

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>

#include <bitstring.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "../common/common.h"
#include "vi.h"

static int ulcase(SCR *, recno_t, CHAR_T *, size_t, size_t, size_t);

/*
 * v_ulcase -- [count]~
 *      Toggle upper & lower case letters.
 *
 * !!!
 * Historic vi didn't permit ~ to cross newline boundaries.  I can
 * think of no reason why it shouldn't, which at least lets the user
 * auto-repeat through a paragraph.
 *
 * !!!
 * In historic vi, the count was ignored.  It would have been better
 * if there had been an associated motion, but it's too late to make
 * that the default now.
 *
 * PUBLIC: int v_ulcase(SCR *, VICMD *);
 */
int
v_ulcase(SCR *sp, VICMD *vp)
{
        recno_t lno;
        size_t cno, lcnt, len;
        u_long cnt;
        char *p;

        lno = vp->m_start.lno;
        cno = vp->m_start.cno;

        for (cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1; cnt > 0; cno = 0) {
                /* SOF is an error, EOF is an infinite count sink. */
                if (db_get(sp, lno, 0, &p, &len)) {
                        if (lno == 1) {
                                v_emsg(sp, NULL, VIM_EMPTY);
                                return (1);
                        }
                        --lno;
                        break;
                }

                /* Empty lines decrement the count by one. */
                if (len == 0) {
                        --cnt;
                        vp->m_final.cno = 0;
                        continue;
                }

                if (cno + cnt >= len) {
                        lcnt = len - 1;
                        cnt -= len - cno;

                        vp->m_final.cno = len - 1;
                } else {
                        lcnt = cno + cnt - 1;
                        cnt = 0;

                        vp->m_final.cno = lcnt + 1;
                }

                if (ulcase(sp, lno, p, len, cno, lcnt))
                        return (1);

                if (cnt > 0)
                        ++lno;
        }

        vp->m_final.lno = lno;
        return (0);
}

/*
 * v_mulcase -- [count]~[count]motion
 *      Toggle upper & lower case letters over a range.
 *
 * PUBLIC: int v_mulcase(SCR *, VICMD *);
 */
int
v_mulcase(SCR *sp, VICMD *vp)
{
        CHAR_T *p;
        size_t len;
        recno_t lno;

        for (lno = vp->m_start.lno;;) {
                if (db_get(sp, lno, DBG_FATAL, (char **) &p, &len))
                        return (1);
                if (len != 0 && ulcase(sp, lno, p, len,
                    lno == vp->m_start.lno ? vp->m_start.cno : 0,
                    !F_ISSET(vp, VM_LMODE) &&
                    lno == vp->m_stop.lno ? vp->m_stop.cno : len))
                        return (1);

                if (++lno > vp->m_stop.lno)
                        break;
        }

        /*
         * XXX
         * I didn't create a new motion command when I added motion semantics
         * for ~.  While that's the correct way to do it, that choice would
         * have required changes all over the vi directory for little gain.
         * Instead, we pretend it's a yank command.  Note, this means that we
         * follow the cursor motion rules for yank commands, but that seems
         * reasonable to me.
         */
        return (0);
}

/*
 * ulcase --
 *      Change part of a line's case.
 */
static int
ulcase(SCR *sp, recno_t lno, CHAR_T *lp, size_t len, size_t scno, size_t ecno)
{
        size_t blen;
        int change, rval;
        CHAR_T ch, *p, *t;
        char *bp;

        GET_SPACE_RET(sp, bp, blen, len);
        memmove(bp, lp, len);

        change = rval = 0;
        for (p = bp + scno, t = bp + ecno + 1; p < t; ++p) {
                ch = *(u_char *)p;
                if (islower(ch)) {
                        *p = toupper(ch);
                        change = 1;
                } else if (isupper(ch)) {
                        *p = tolower(ch);
                        change = 1;
                }
        }

        if (change && db_set(sp, lno, bp, len))
                rval = 1;

        FREE_SPACE(sp, bp, blen);
        return (rval);
}