/*      $OpenBSD: msg.c,v 1.28 2022/12/26 19:16:03 jmc Exp $    */

/*-
 * Copyright (c) 1991, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1991, 1993, 1994, 1995, 1996
 *      Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 */

#include "config.h"

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

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

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

/*
 * msgq --
 *      Display a message.
 *
 * PUBLIC: void msgq(SCR *, mtype_t, const char *, ...);
 */
void
msgq(SCR *sp, mtype_t mt, const char *fmt, ...)
{
        static int reenter;             /* STATIC: Re-entrancy check. */
        GS *gp;
        size_t blen, len, mlen, nlen;
        const char *p;
        char *bp, *mp;
        va_list ap;

        /*
         * !!!
         * It's possible to enter msg when there's no screen to hold the
         * message.  If sp is NULL, ignore the special cases and put the
         * message out to stderr.
         */
        if (sp == NULL) {
                gp = NULL;
                if (mt == M_BERR)
                        mt = M_ERR;
                else if (mt == M_VINFO)
                        mt = M_INFO;
        } else {
                gp = sp->gp;
                switch (mt) {
                case M_BERR:
                        if (F_ISSET(sp, SC_VI) && !O_ISSET(sp, O_VERBOSE)) {
                                F_SET(gp, G_BELLSCHED);
                                return;
                        }
                        mt = M_ERR;
                        break;
                case M_VINFO:
                        if (!O_ISSET(sp, O_VERBOSE))
                                return;
                        mt = M_INFO;
                        /* FALLTHROUGH */
                case M_INFO:
                        if (F_ISSET(sp, SC_EX_SILENT))
                                return;
                        break;
                case M_ERR:
                case M_SYSERR:
                        break;
                default:
                        abort();
                }
        }

        /*
         * It's possible to reenter msg when it allocates space.  We're
         * probably dead anyway, but there's no reason to drop core.
         *
         * XXX
         * Yes, there's a race, but it should only be two instructions.
         */
        if (reenter++)
                return;

        /* Get space for the message. */
        nlen = 1024;
        if (0) {
retry:          FREE_SPACE(sp, bp, blen);
                nlen *= 2;
        }
        bp = NULL;
        blen = 0;
        GET_SPACE_GOTO(sp, bp, blen, nlen);

        /*
         * Error prefix.
         *
         * mp:   pointer to the current next character to be written
         * mlen: length of the already written characters
         * blen: total length of the buffer
         */
#define REM     (blen - mlen)
        mp = bp;
        mlen = 0;
        if (mt == M_SYSERR) {
                p = "Error: ";
                len = strlen(p);
                if (REM < len)
                        goto retry;
                memcpy(mp, p, len);
                mp += len;
                mlen += len;
        }

        /*
         * If we're running an ex command that the user didn't enter, display
         * the file name and line number prefix.
         */
        if ((mt == M_ERR || mt == M_SYSERR) &&
            sp != NULL && gp != NULL && gp->if_name != NULL) {
                for (p = gp->if_name; *p != '\0'; ++p) {
                        len = snprintf(mp, REM, "%s", KEY_NAME(sp, *p));
                        mp += len;
                        if ((mlen += len) > blen)
                                goto retry;
                }
                len = snprintf(mp, REM, ", %d: ", gp->if_lno);
                mp += len;
                if ((mlen += len) > blen)
                        goto retry;
        }

        /* If nothing to format, we're done. */
        if (fmt == NULL) {
                len = 0;
                goto nofmt;
        }

        /* Format the arguments into the string. */
        va_start(ap, fmt);
        len = vsnprintf(mp, REM, fmt, ap);
        va_end(ap);
        if (len >= nlen)
                goto retry;

nofmt:  mp += len;
        if ((mlen += len) > blen)
                goto retry;
        if (mt == M_SYSERR) {
                len = snprintf(mp, REM, ": %s", strerror(errno));
                mp += len;
                if ((mlen += len) > blen)
                        goto retry;
                mt = M_ERR;
        }

        /* Add trailing newline. */
        if ((mlen += 1) > blen)
                goto retry;
        *mp = '\n';

        if (sp != NULL)
                (void)ex_fflush(sp);
        if (gp != NULL)
                gp->scr_msg(sp, mt, bp, mlen);
        else
                (void)fprintf(stderr, "%.*s", (int)mlen, bp);

        /* Cleanup. */
        FREE_SPACE(sp, bp, blen);
alloc_err:
        reenter = 0;
}

/*
 * msgq_str --
 *      Display a message with an embedded string.
 *
 * PUBLIC: void msgq_str(SCR *, mtype_t, char *, char *);
 */
void
msgq_str(SCR *sp, mtype_t mtype, char *str, char *fmt)
{
        int nf, sv_errno;
        char *p;

        if (str == NULL) {
                msgq(sp, mtype, fmt);
                return;
        }

        sv_errno = errno;
        p = msg_print(sp, str, &nf);
        errno = sv_errno;
        msgq(sp, mtype, fmt, p);
        if (nf)
                FREE_SPACE(sp, p, 0);
}

/*
 * mod_rpt --
 *      Report on the lines that changed.
 *
 * !!!
 * Historic vi documentation (USD:15-8) claimed that "The editor will also
 * always tell you when a change you make affects text which you cannot see."
 * This wasn't true -- edit a large file and do "100d|1".  We don't implement
 * this semantic since it requires tracking each line that changes during a
 * command instead of just keeping count.
 *
 * Line counts weren't right in historic vi, either.  For example, given the
 * file:
 *      abc
 *      def
 * the command 2d}, from the 'b' would report that two lines were deleted,
 * not one.
 *
 * PUBLIC: void mod_rpt(SCR *);
 */
void
mod_rpt(SCR *sp)
{
        static char * const action[] = {
                "added",
                "changed",
                "deleted",
                "joined",
                "moved",
                "shifted",
                "yanked",
        };
        static char * const lines[] = {
                "line",
                "lines",
        };
        recno_t total;
        u_long rptval;
        int first, cnt;
        size_t blen, len, tlen;
        const char *t;
        char * const *ap;
        char *bp, *p;

        /* Change reports are turned off in batch mode. */
        if (F_ISSET(sp, SC_EX_SILENT))
                return;

        /* Reset changing line number. */
        sp->rptlchange = OOBLNO;

        /*
         * Don't build a message if not enough changed.
         *
         * !!!
         * And now, a vi clone test.  Historically, vi reported if the number
         * of changed lines was > than the value, not >=, unless it was a yank
         * command, which used >=.  No lie.  Furthermore, an action was never
         * reported for a single line action.  This is consistent for actions
         * other than yank, but yank didn't report single line actions even if
         * the report edit option was set to 1.  In addition, setting report to
         * 0 in the 4BSD historic vi was equivalent to setting it to 1, for an
         * unknown reason (this bug was fixed in System III/V at some point).
         * I got complaints, so nvi conforms to System III/V historic practice
         * except that we report a yank of 1 line if report is set to 1.
         */
#define ARSIZE(a)       sizeof(a) / sizeof (*a)
#define MAXNUM          25
        rptval = O_VAL(sp, O_REPORT);
        for (cnt = 0, total = 0; cnt < ARSIZE(action); ++cnt)
                total += sp->rptlines[cnt];
        if (total == 0)
                return;
        if (total <= rptval && sp->rptlines[L_YANKED] < rptval) {
                for (cnt = 0; cnt < ARSIZE(action); ++cnt)
                        sp->rptlines[cnt] = 0;
                return;
        }

        /* Build and display the message. */
        GET_SPACE_GOTO(sp, bp, blen, sizeof(action) * MAXNUM + 1);
        for (p = bp, first = 1, tlen = 0,
            ap = action, cnt = 0; cnt < ARSIZE(action); ++ap, ++cnt)
                if (sp->rptlines[cnt] != 0) {
                        if (first)
                                first = 0;
                        else {
                                *p++ = ';';
                                *p++ = ' ';
                                tlen += 2;
                        }
                        len = snprintf(p, MAXNUM, "%u ", sp->rptlines[cnt]);
                        p += len;
                        tlen += len;
                        t = lines[sp->rptlines[cnt] == 1 ? 0 : 1];
                        len = strlen(t);
                        memcpy(p, t, len);
                        p += len;
                        tlen += len;
                        *p++ = ' ';
                        ++tlen;
                        len = strlen(*ap);
                        memcpy(p, *ap, len);
                        p += len;
                        tlen += len;
                        sp->rptlines[cnt] = 0;
                }

        /* Add trailing newline. */
        *p = '\n';
        ++tlen;

        (void)ex_fflush(sp);
        sp->gp->scr_msg(sp, M_INFO, bp, tlen);

        FREE_SPACE(sp, bp, blen);
alloc_err:
        return;

#undef ARSIZE
#undef MAXNUM
}

/*
 * msgq_status --
 *      Report on the file's status.
 *
 * PUBLIC: void msgq_status(SCR *, recno_t, u_int);
 */
void
msgq_status(SCR *sp, recno_t lno, u_int flags)
{
        recno_t last;
        size_t blen, len;
        int cnt, needsep;
        const char *t;
        char **ap, *bp, *np, *p, *s, *ep;

        /* Get sufficient memory. */
        len = strlen(sp->frp->name);
        GET_SPACE_GOTO(sp, bp, blen, len * MAX_CHARACTER_COLUMNS + 128);
        p = bp;
        ep = bp + blen;

        /* Copy in the filename. */
        for (t = sp->frp->name; *t != '\0'; ++t) {
                len = KEY_LEN(sp, *t);
                memcpy(p, KEY_NAME(sp, *t), len);
                p += len;
        }
        np = p;
        *p++ = ':';
        *p++ = ' ';

        /* Copy in the argument count. */
        if (F_ISSET(sp, SC_STATUS_CNT) && sp->argv != NULL) {
                for (cnt = 0, ap = sp->argv; *ap != NULL; ++ap, ++cnt);
                if (cnt > 1) {
                        (void)snprintf(p, ep - p, "%d files to edit", cnt);
                        p += strlen(p);
                        *p++ = ':';
                        *p++ = ' ';
                }
                F_CLR(sp, SC_STATUS_CNT);
        }

        /*
         * See nvi/exf.c:file_init() for a description of how and when the
         * read-only bit is set.
         *
         * !!!
         * The historic display for "name changed" was "[Not edited]".
         */
        needsep = 0;
        if (F_ISSET(sp->frp, FR_NEWFILE)) {
                F_CLR(sp->frp, FR_NEWFILE);
                len = strlen("new file");
                memcpy(p, "new file", len);
                p += len;
                needsep = 1;
        } else {
                if (F_ISSET(sp->frp, FR_NAMECHANGE)) {
                        len = strlen("name changed");
                        memcpy(p, "name changed", len);
                        p += len;
                        needsep = 1;
                }
                if (needsep) {
                        *p++ = ',';
                        *p++ = ' ';
                }
                t = (F_ISSET(sp->ep, F_MODIFIED)) ? "modified" : "unmodified";
                len = strlen(t);
                memcpy(p, t, len);
                p += len;
                needsep = 1;
        }
        if (F_ISSET(sp->frp, FR_UNLOCKED)) {
                if (needsep) {
                        *p++ = ',';
                        *p++ = ' ';
                }
                len = strlen("UNLOCKED");
                memcpy(p, "UNLOCKED", len);
                p += len;
                needsep = 1;
        }
        if (O_ISSET(sp, O_READONLY)) {
                if (needsep) {
                        *p++ = ',';
                        *p++ = ' ';
                }
                len = strlen("readonly");
                memcpy(p, "readonly", len);
                p += len;
                needsep = 1;
        }
        if (needsep) {
                *p++ = ':';
                *p++ = ' ';
        }
        if (LF_ISSET(MSTAT_SHOWLAST)) {
                if (db_last(sp, &last))
                        return;
                if (last == 0) {
                        len = strlen("empty file");
                        memcpy(p, "empty file", len);
                        p += len;
                } else {
                        (void)snprintf(p, ep - p, "line %lu of %lu [%lu%%]",
                            (unsigned long)lno, (unsigned long)last,
                            (unsigned long)(lno * 100) / last);
                        p += strlen(p);
                }
        } else {
                (void)snprintf(p, ep - p, "line %lu", (unsigned long)lno);
                p += strlen(p);
        }
#ifdef DEBUG
        (void)snprintf(p, ep - p, " (pid %ld)", (long)getpid());
        p += strlen(p);
#endif
        *p++ = '\n';
        len = p - bp;

        /*
         * There's a nasty problem with long path names.  Tags files
         * can result in long paths and vi will request a continuation key from
         * the user as soon as it starts the screen.  Unfortunately, the user
         * has already typed ahead, and chaos results.  If we assume that the
         * characters in the filenames and informational messages only take a
         * single screen column each, we can trim the filename.
         *
         * XXX
         * Status lines get put up at fairly awkward times.  For example, when
         * you do a filter read (e.g., :read ! echo foo) in the top screen of a
         * split screen, we have to repaint the status lines for all the screens
         * below the top screen.  We don't want users having to enter continue
         * characters for those screens.  Make it really hard to screw this up.
         */
        s = bp;
        if (LF_ISSET(MSTAT_TRUNCATE) && len > sp->cols) {
                for (; s < np && (*s != '/' || (p - s) > sp->cols - 3); ++s);
                if (s == np) {
                        s = p - (sp->cols - 5);
                        *--s = ' ';
                }
                *--s = '.';
                *--s = '.';
                *--s = '.';
                len = p - s;
        }

        /* Flush any waiting ex messages. */
        (void)ex_fflush(sp);

        sp->gp->scr_msg(sp, M_INFO, s, len);

        FREE_SPACE(sp, bp, blen);
alloc_err:
        return;
}

/*
 * msg_cont --
 *      Return common continuation messages.
 *
 * PUBLIC: const char *msg_cmsg(SCR *, cmsg_t, size_t *);
 */
const char *
msg_cmsg(SCR *sp, cmsg_t which, size_t *lenp)
{
        const char *s;
        switch (which) {
        case CMSG_CONF:
                s = "confirm? [ynq]";
                break;
        case CMSG_CONT:
                s = "Press any key to continue: ";
                break;
        case CMSG_CONT_EX:
                s = "Press any key to continue [: to enter more ex commands]: ";
                break;
        case CMSG_CONT_R:
                s = "Press Enter to continue: ";
                break;
        case CMSG_CONT_S:
                s = " cont?";
                break;
        case CMSG_CONT_Q:
                s = "Press any key to continue [q to quit]: ";
                break;
        default:
                abort();
        }
        *lenp = strlen(s);
        return s;
}

/*
 * msg_print --
 *      Return a printable version of a string, in allocated memory.
 *
 * PUBLIC: char *msg_print(SCR *, const char *, int *);
 */
char *
msg_print(SCR *sp, const char *s, int *needfree)
{
        size_t blen, nlen;
        const char *cp;
        char *bp, *ep, *p, *t;

        *needfree = 0;

        for (cp = s; *cp != '\0'; ++cp)
                if (!isprint(*cp))
                        break;
        if (*cp == '\0')
                return ((char *)s);     /* SAFE: needfree set to 0. */

        nlen = 0;
        if (0) {
retry:          if (sp == NULL)
                        free(bp);
                else
                        FREE_SPACE(sp, bp, blen);
                *needfree = 0;
        }
        nlen += 256;
        if (sp == NULL) {
                if ((bp = malloc(nlen)) == NULL)
                        goto alloc_err;
                blen = 0;
        } else
                GET_SPACE_GOTO(sp, bp, blen, nlen);
        if (0) {
alloc_err:      return ("");
        }
        *needfree = 1;

        for (p = bp, ep = (bp + blen) - 1, cp = s; *cp != '\0' && p < ep; ++cp)
                for (t = KEY_NAME(sp, *cp); *t != '\0' && p < ep; *p++ = *t++);
        if (p == ep)
                goto retry;
        *p = '\0';
        return (bp);
}