/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1980, 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */



#include <sys/param.h>

#include <ctype.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "systat.h"
#include "extern.h"

void
command(const char *cmd)
{
        struct cmdtab *p;
        char *cp, *tmpstr, *tmpstr1;
        double t;

        tmpstr = tmpstr1 = strdup(cmd);
        for (cp = tmpstr1; *cp && !isspace(*cp); cp++)
                ;
        if (*cp)
                *cp++ = '\0';
        if (*tmpstr1 == '\0')
                goto done;
        for (; *cp && isspace(*cp); cp++)
                ;
        if (strcmp(tmpstr1, "quit") == 0 || strcmp(tmpstr1, "q") == 0)
                die(0);
        if (strcmp(tmpstr1, "load") == 0) {
                load();
                goto done;
        }
        if (strcmp(tmpstr1, "stop") == 0) {
                delay = 0;
                mvaddstr(CMDLINE, 0, "Refresh disabled.");
                clrtoeol();
                goto done;
        }
        if (strcmp(tmpstr1, "help") == 0) {
                int _col, _len;

                move(CMDLINE, _col = 0);
                for (p = cmdtab; p->c_name; p++) {
                        _len = strlen(p->c_name);
                        if (_col + _len > COLS)
                                break;
                        addstr(p->c_name); _col += _len;
                        if (_col + 1 < COLS)
                                addch(' ');
                }
                clrtoeol();
                goto done;
        }
        t = strtod(tmpstr1, NULL) * 1000000.0;
        if (t > 0 && t < (double)UINT_MAX)
                delay = (unsigned int)t;
        if ((t <= 0 || t > (double)UINT_MAX) &&
            (strcmp(tmpstr1, "start") == 0 ||
            strcmp(tmpstr1, "interval") == 0)) {
                if (*cp != '\0') {
                        t = strtod(cp, NULL) * 1000000.0;
                        if (t <= 0 || t >= (double)UINT_MAX) {
                                error("%d: bad interval.", (int)t);
                                goto done;
                        }
                }
        }
        if (t > 0) {
                delay = (unsigned int)t;
                display();
                status();
                goto done;
        }
        p = lookup(tmpstr1);
        if (p == (struct cmdtab *)-1) {
                error("%s: Ambiguous command.", tmpstr1);
                goto done;
        }
        if (p) {
                if (curcmd == p)
                        goto done;
                (*curcmd->c_close)(wnd);
                curcmd->c_flags &= ~CF_INIT;
                wnd = (*p->c_open)();
                if (wnd == NULL) {
                        error("Couldn't open new display");
                        wnd = (*curcmd->c_open)();
                        if (wnd == NULL) {
                                error("Couldn't change back to previous cmd");
                                exit(1);
                        }
                        p = curcmd;
                }
                if ((p->c_flags & CF_INIT) == 0) {
                        if ((*p->c_init)())
                                p->c_flags |= CF_INIT;
                        else
                                goto done;
                }
                curcmd = p;
                labels();
                display();
                status();
                goto done;
        }
        if (curcmd->c_cmd == NULL || !(*curcmd->c_cmd)(tmpstr1, cp))
                error("%s: Unknown command.", tmpstr1);
done:
        free(tmpstr);
}

struct cmdtab *
lookup(const char *name)
{
        const char *p, *q;
        struct cmdtab *ct, *found;
        int nmatches, longest;

        longest = 0;
        nmatches = 0;
        found = (struct cmdtab *) 0;
        for (ct = cmdtab; (p = ct->c_name); ct++) {
                for (q = name; *q == *p++; q++)
                        if (*q == 0)            /* exact match? */
                                return (ct);
                if (!*q) {                      /* the name was a prefix */
                        if (q - name > longest) {
                                longest = q - name;
                                nmatches = 1;
                                found = ct;
                        } else if (q - name == longest)
                                nmatches++;
                }
        }
        if (nmatches > 1)
                return ((struct cmdtab *)-1);
        return (found);
}

void
status(void)
{

        error("Showing %s, refresh every %d seconds.",
          curcmd->c_name, delay / 1000000);
}

int
prefix(const char *s1, const char *s2)
{

        while (*s1 == *s2) {
                if (*s1 == '\0')
                        return (1);
                s1++, s2++;
        }
        return (*s1 == '\0');
}