/*

KDM remote control application

Copyright (C) 2004 Oswald Buddenhagen <ossi@kde.org>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

*/

#include <config-workspace.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <sys/socket.h>
#include <sys/un.h>

static int
openCtl(int fd, int err, const char *ctl, const char *dpy)
{
    struct sockaddr_un sa;

    sa.sun_family = AF_UNIX;
    if (dpy)
        snprintf(sa.sun_path, sizeof(sa.sun_path),
                 "%s/dmctl-%s/socket", ctl, dpy);
    else
        snprintf(sa.sun_path, sizeof(sa.sun_path),
                 "%s/dmctl/socket", ctl);
    if (!connect(fd, (struct sockaddr *)&sa, sizeof(sa)))
        return 1;
    if (err)
        fprintf(stderr, "Cannot connect socket '%s'.\n", sa.sun_path);
    return 0;
}

static const char *
readConfig(const char *cfg)
{
    FILE *fp;
    const char *ctl;
    char *ptr, *ptr2;
    char buf[1024];

    if (!(fp = fopen(cfg, "r"))) {
        fprintf(stderr,
                "Cannot open kdm config file '%s'.\n",
                cfg);
        return 0;
    }
    ctl = "/var/run/xdmctl";
    while (fgets(buf, sizeof(buf), fp))
        if (!strncmp(buf, "FifoDir", 7)) {
            ptr = buf + 7;
            while (*ptr && isspace(*ptr))
                ptr++;
            if (*ptr++ != '=')
                continue;
            while (*ptr && isspace(*ptr))
                ptr++;
            for (ptr2 = buf + strlen(buf);
                 ptr2 > ptr && isspace(*(ptr2 - 1));
                 ptr2--);
            *ptr2 = 0;
            ctl = strdup(ptr);
            break;
        }
    fclose(fp);
    return ctl;
}

static int
exe(int fd, const char *in, int len)
{
    char buf[4096];

    if (write(fd, in, len) != len) {
        fprintf(stderr, "Cannot send command\n");
        return 1;
    }
    do {
        if ((len = read(fd, buf, sizeof(buf))) <= 0) {
            fprintf(stderr, "Cannot receive reply\n");
            return 1;
        }
        fwrite(buf, 1, len, stdout);
    } while (buf[len - 1] != '\n');
    return 0;
}

static int
run(int fd, char **argv)
{
    unsigned len, l;
    char buf[1024];

    if (!*argv)
        return exe(fd, "caps\n", 5);
    if (!strcmp(*argv, "-")) {
        for (;;) {
            if (isatty(0)) {
                fputs("> ", stdout);
                fflush(stdout);
            }
            if (!fgets(buf, sizeof(buf), stdin))
                return 0;
            if (exe(fd, buf, strlen(buf)))
                return 1;
        }
    } else {
        len = strlen(*argv);
        if (len >= sizeof(buf))
            goto bad;
        memcpy(buf, *argv, len);
        while (*++argv) {
            l = strlen(*argv);
            if (len + l + 1 >= sizeof(buf))
                goto bad;
            buf[len++] = '\t';
            memcpy(buf + len, *argv, l);
            len += l;
        }
        buf[len++] = '\n';
        return exe(fd, buf, len);
      bad:
        fprintf(stderr, "Command too long\n");
        return 1;
    }
}

int
main(int argc, char **argv)
{
    char *dpy = getenv("DISPLAY");
    const char *ctl = getenv("DM_CONTROL");
    const char *cfg = KDE_CONFDIR "/kdm/kdmrc";
    char *ptr;
    int fd;

    (void)argc;
    while (*++argv) {
        ptr = *argv;
        if (*ptr != '-' || !*(ptr + 1))
            break;
        ptr++;
        if (*ptr == '-')
            ptr++;
        if (!strcmp(ptr, "h") || !strcmp(ptr, "help")) {
            puts(
"Usage: kdmctl [options] [command [command arguments]]\n"
"\n"
"Options are:\n"
" -h -help     This help message.\n"
" -g -global   Use global control socket even if $DISPLAY is set\n"
" -d -display  Override $DISPLAY\n"
" -s -sockets  Override $DM_CONTROL\n"
" -c -config   Use alternative kdm config file\n"
"\n"
"The directory in which the sockets are located is determined this way:\n"
"- the -s option is examined\n"
"- the $DM_CONTROL variable is examined\n"
"- the kdm config file is searched for the FifoDir key\n"
"- /var/run/xdmctl and /var/run are tried\n"
"\n"
"If $DISPLAY is set (or -d was specified) and -g was not specified, the\n"
"display-specific control socket will be used, otherwise the global one.\n"
"\n"
"Tokens in the command and the reply are tab-separated.\n"
"Command arguments can be specified as separate command line parameters,\n"
"in which case they are simply concatenated with tabs in between.\n"
"\n"
"If the command is '-', kdmctl reads commands from stdin.\n"
"The default command is 'caps'.\n"
           );
            return 0;
        } else if (!strcmp(ptr, "g") || !strcmp(ptr, "global")) {
            dpy = 0;
        } else if (!strcmp(ptr, "d") || !strcmp(ptr, "display")) {
            if (!argv[1])
                goto needarg;
            dpy = *++argv;
        } else if (!strcmp(ptr, "s") || !strcmp(ptr, "sockets")) {
            if (!argv[1])
                goto needarg;
            ctl = *++argv;
        } else if (!strcmp(ptr, "c") || !strcmp(ptr, "config")) {
            if (!argv[1]) {
              needarg:
                fprintf(stderr, "Option '%s' needs argument.\n", ptr);
                return 1;
            }
            cfg = *++argv;
        } else {
            fprintf(stderr, "Unknown option '%s'.\n", ptr);
            return 1;
        }
    }
    if ((!ctl || !*ctl) && *cfg)
        ctl = readConfig(cfg);
    if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
        fprintf(stderr, "Cannot create UNIX socket\n");
        return 1;
    }
    if (dpy && (ptr = strchr(dpy, ':')) && (ptr = strchr(ptr, '.')))
        *ptr = 0;
    if (ctl && *ctl) {
        if (!openCtl(fd, 1, ctl, dpy))
            return 1;
    } else {
        if (!openCtl(fd, 0, "/var/run/xdmctl", dpy) &&
            !openCtl(fd, 0, "/var/run", dpy))
        {
            fprintf(stderr, "No command socket found.\n");
            return 1;
        }
    }
    return run(fd, argv);
}