/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2002 Jonathan Belson <jon@witchspace.com>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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/types.h>
#include <sys/queue.h>
#include <sys/sysctl.h>

#include <assert.h>
#include <bsddialog.h>
#include <ctype.h>
#include <dirent.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stringlist.h>
#include <unistd.h>

#include "kbdmap.h"


static const char *lang_default = DEFAULT_LANG;
static const char *font;
static const char *lang;
static const char *program;
static const char *keymapdir = DEFAULT_VT_KEYMAP_DIR;
static const char *fontdir = DEFAULT_VT_FONT_DIR;
static const char *font_default = DEFAULT_VT_FONT;
static const char *sysconfig = DEFAULT_SYSCONFIG;
static const char *font_current;
static const char *dir;
static const char *menu = "";
static const char *title = "Keyboard Menu";

static int x11;
static int using_vt;
static int show;
static int verbose;
static int print;


struct keymap {
        char    *desc;
        char    *keym;
        int     mark;
        SLIST_ENTRY(keymap) entries;
};
static SLIST_HEAD(slisthead, keymap) head = SLIST_HEAD_INITIALIZER(head);


/*
 * Get keymap entry for 'key', or NULL of not found
 */
static struct keymap *
get_keymap(const char *key)
{
        struct keymap *km;

        SLIST_FOREACH(km, &head, entries)
                if (!strcmp(km->keym, key))
                        return km;

        return NULL;
}

/*
 * Count the number of keymaps we found
 */
static int
get_num_keymaps(void)
{
        struct keymap *km;
        int count = 0;

        SLIST_FOREACH(km, &head, entries)
                count++;

        return count;
}

/*
 * Remove any keymap with given keym
 */
static void
remove_keymap(const char *keym)
{
        struct keymap *km;

        SLIST_FOREACH(km, &head, entries) {
                if (!strcmp(keym, km->keym)) {
                        SLIST_REMOVE(&head, km, keymap, entries);
                        free(km);
                        break;
                }
        }
}

/*
 * Add to hash with 'key'
 */
static void
add_keymap(const char *desc, int mark, const char *keym)
{
        struct keymap *km, *km_new;

        /* Is there already an entry with this key? */
        SLIST_FOREACH(km, &head, entries) {
                if (!strcmp(km->keym, keym)) {
                        /* Reuse this entry */
                        free(km->desc);
                        km->desc = strdup(desc);
                        km->mark = mark;
                        return;
                }
        }

        km_new = (struct keymap *) malloc (sizeof(struct keymap));
        km_new->desc = strdup(desc);
        km_new->keym = strdup(keym);
        km_new->mark = mark;

        /* Add to keymap list */
        SLIST_INSERT_HEAD(&head, km_new, entries);
}

/*
 * Return 0 if syscons is in use (to select legacy defaults).
 */
static int
check_vt(void)
{
        size_t len;
        char term[3];

        len = 3;
        if (sysctlbyname("kern.vty", &term, &len, NULL, 0) != 0 ||
            strcmp(term, "vt") != 0)
                return 0;
        return 1;
}

/*
 * Figure out the default language to use.
 */
static const char *
get_locale(void)
{
        const char *locale;

        if ((locale = getenv("LC_ALL")) == NULL &&
            (locale = getenv("LC_CTYPE")) == NULL &&
            (locale = getenv("LANG")) == NULL)
                locale = lang_default;

        /* Check for alias */
        if (!strcmp(locale, "C"))
                locale = DEFAULT_LANG;

        return locale;
}

/*
 * Extract filename part
 */
static const char *
extract_name(const char *name)
{
        char *p;

        p = strrchr(name, '/');
        if (p != NULL && p[1] != '\0')
                return p + 1;

        return name;
}

/*
 * Return file extension or NULL
 */
static char *
get_extension(const char *name)
{
        char *p;

        p = strrchr(name, '.');

        if (p != NULL && p[1] != '\0')
                return p;

        return NULL;
}

/*
 * Read font from /etc/rc.conf else return default.
 * Freeing the memory is the caller's responsibility.
 */
static char *
get_font(void)
{
        char line[256], buf[21];
        char *fnt = NULL;

        FILE *fp = fopen(sysconfig, "r");
        if (fp) {
                while (fgets(line, sizeof(line), fp)) {
                        int a, b, matches;

                        if (line[0] == '#')
                                continue;

                        matches = sscanf(line,
                            " font%dx%d = \"%20[-.0-9a-zA-Z_]",
                            &a, &b, buf);
                        if (matches==3) {
                                if (strcmp(buf, "NO")) {
                                        if (fnt)
                                                free(fnt);
                                        fnt = strdup(buf);
                                }
                        }
                }
                fclose(fp);
        } else
                fprintf(stderr, "Could not open %s for reading\n", sysconfig);

        return fnt;
}

/*
 * Set a font using 'vidcontrol'
 */
static void
vidcontrol(const char *fnt)
{
        char *tmp, *p, *q, *cmd;
        char ch;
        int i;

        /* syscons test failed */
        if (x11)
                return;

        if (using_vt) {
                asprintf(&cmd, "vidcontrol -f %s", fnt);
                system(cmd);
                free(cmd);
                return;
        }

        tmp = strdup(fnt);

        /* Extract font size */
        p = strrchr(tmp, '-');
        if (p && p[1] != '\0') {
                p++;
                /* Remove any '.fnt' extension */
                if ((q = strstr(p, ".fnt")))
                        *q = '\0';

                /*
                 * Check font size is valid, with no trailing characters
                 *  ('&ch' should not be matched)
                 */
                if (sscanf(p, "%dx%d%c", &i, &i, &ch) != 2)
                        fprintf(stderr, "Which font size? %s\n", fnt);
                else {
                        asprintf(&cmd, "vidcontrol -f %s %s", p, fnt);
                        if (verbose)
                                fprintf(stderr, "%s\n", cmd);
                        system(cmd);
                        free(cmd);
                }
        } else
                fprintf(stderr, "Which font size? %s\n", fnt);

        free(tmp);
}

/*
 * Execute 'kbdcontrol' with the appropriate arguments
 */
static void
do_kbdcontrol(struct keymap *km)
{
        char *kbd_cmd;
        asprintf(&kbd_cmd, "kbdcontrol -l %s/%s", dir, km->keym);

        if (!x11)
                system(kbd_cmd);

        fprintf(stderr, "keymap=\"%s\"\n", km->keym);
        free(kbd_cmd);
}

/*
 * Call 'vidcontrol' with the appropriate arguments
 */
static void
do_vidfont(struct keymap *km)
{
        char *vid_cmd, *tmp, *p, *q;

        asprintf(&vid_cmd, "%s/%s", dir, km->keym);
        vidcontrol(vid_cmd);
        free(vid_cmd);

        tmp = strdup(km->keym);
        p = strrchr(tmp, '-');
        if (p && p[1]!='\0') {
                p++;
                q = get_extension(p);
                if (q) {
                        *q = '\0';
                        printf("font%s=%s\n", p, km->keym);
                }
        }
        free(tmp);
}

/*
 * Display dialog from 'keymaps[]'
 */
static void
show_dialog(struct keymap **km_sorted, int num_keymaps)
{
        struct bsddialog_conf conf;
        struct bsddialog_menuitem *listitems;
        int i, result;

        if (bsddialog_init() == BSDDIALOG_ERROR) {
                fprintf(stderr, "Error bsddialog: %s\n", bsddialog_geterror());
                exit(1);
        }
        conf.title = __DECONST(char *, title);

        listitems = calloc(num_keymaps + 1, sizeof(struct bsddialog_menuitem));
        if (listitems == NULL) {
                fprintf(stderr, "Failed to allocate memory in show_dialog");
                bsddialog_end();
                exit(1);
        }

        /* start right font, assume that current font is equal
         * to default font in /etc/rc.conf
         *      
         * $font is the font which require the language $lang; e.g.
         * russian *need* a koi8 font
         * $font_current is the current font from /etc/rc.conf
         */
        if (font && strcmp(font, font_current))
                vidcontrol(font);

        /* Build up the menu */
        for (i=0; i<num_keymaps; i++) {
                listitems[i].prefix = "";
                listitems[i].depth = 0;
                listitems[i].bottomdesc = "";
                listitems[i].on = false;
                listitems[i].name = km_sorted[i]->desc;
                listitems[i].desc = "";
        }
        bsddialog_initconf(&conf);
        conf.title = title;
        conf.clear = true;
        conf.key.enable_esc = true;
        result = bsddialog_menu(&conf, menu, 0, 0, 0, num_keymaps, listitems,
            NULL);
        if (result == BSDDIALOG_ERROR)
                fprintf(stderr, "Error bsddialog: %s\n", bsddialog_geterror());
        bsddialog_end();

        switch (result) {
        case BSDDIALOG_OK:
                for (i = 0; i < num_keymaps; i++) {
                        if (listitems[i].on) {
                                if (!strcmp(program, "kbdmap"))
                                        do_kbdcontrol(km_sorted[i]);
                                else
                                        do_vidfont(km_sorted[i]);
                                break;
                        }
                }
                break;
        default:
                if (font != NULL && strcmp(font, font_current))
                        /* Cancelled, restore old font */
                        vidcontrol(font_current);
                break;
        }
}

/*
 * Search for 'token' in comma delimited array 'buffer'.
 * Return true for found, false for not found.
 */
static int
find_token(const char *buffer, const char *token)
{
        char *buffer_tmp, *buffer_copy, *inputstring;
        char **ap;
        int found;

        buffer_copy = strdup(buffer);
        buffer_tmp = buffer_copy;
        inputstring = buffer_copy;
        ap = &buffer_tmp;

        found = 0;

        while ((*ap = strsep(&inputstring, ",")) != NULL) {
                if (strcmp(buffer_tmp, token) == 0) {
                        found = 1;
                        break;
                }
        }

        free(buffer_copy);

        return found;
}

/*
 * Compare function for qsort
 */
static int
compare_keymap(const void *a, const void *b)
{

        /* We've been passed pointers to pointers, so: */
        const struct keymap *km1 = *((const struct keymap * const *) a);
        const struct keymap *km2 = *((const struct keymap * const *) b);

        return strcmp(km1->desc, km2->desc);
}

/*
 * Compare function for qsort
 */
static int
compare_lang(const void *a, const void *b)
{
        const char *l1 = *((const char * const *) a);
        const char *l2 = *((const char * const *) b);

        return strcmp(l1, l2);
}

/*
 * Change '8x8' to '8x08' so qsort will put it before eg. '8x14'
 */
static void
kludge_desc(struct keymap **km_sorted, int num_keymaps)
{
        int i;

        for (i=0; i<num_keymaps; i++) {
                char *p;
                char *km = km_sorted[i]->desc;
                if ((p = strstr(km, "8x8")) != NULL) {
                        int len;
                        int j;
                        int offset;

                        offset = p - km;

                        /* Make enough space for the extra '0' */
                        len = strlen(km);
                        km = realloc(km, len + 2);

                        for (j=len; j!=offset+1; j--)
                                km[j + 1] = km[j];

                        km[offset+2] = '0';

                        km_sorted[i]->desc = km;
                }
        }
}

/*
 * Reverse 'kludge_desc()' - change '8x08' back to '8x8'
 */
static void
unkludge_desc(struct keymap **km_sorted, int num_keymaps)
{
        int i;

        for (i=0; i<num_keymaps; i++) {
                char *p;
                char *km = km_sorted[i]->desc;
                if ((p = strstr(km, "8x08")) != NULL) {
                        p += 2;
                        while (*p++)
                                p[-1] = p[0];

                        km = realloc(km, p - km - 1);
                        km_sorted[i]->desc = km;
                }
        }
}

/*
 * Return 0 if file exists and is readable, else -1
 */
static int
check_file(const char *keym)
{
        int status = 0;

        if (access(keym, R_OK) == -1) {
                char *fn;
                asprintf(&fn, "%s/%s", dir, keym);
                if (access(fn, R_OK) == -1) {
                        if (verbose)
                                fprintf(stderr, "%s not found!\n", fn);
                        status = -1;
                }
                free(fn);
        } else {
                if (verbose)
                        fprintf(stderr, "No read permission for %s!\n", keym);
                status = -1;
        }

        return status;
}

/*
 * Read options from the relevant configuration file, then
 *  present to user.
 */
static void
menu_read(void)
{
        const char *lg;
        char *p;
        int mark, num_keymaps, items, i;
        char buffer[256], filename[PATH_MAX];
        char keym[65], lng[65], desc[257];
        char dialect[64], lang_abk[64];
        struct keymap *km;
        struct keymap **km_sorted;
        struct dirent *dp;
        StringList *lang_list;
        FILE *fp;
        DIR *dirp;

        lang_list = sl_init();

        sprintf(filename, "%s/INDEX.%s", dir, extract_name(dir));

        /* en_US.ISO8859-1 -> en_..\.ISO8859-1 */
        strlcpy(dialect, lang, sizeof(dialect));
        if (strlen(dialect) >= 6 && dialect[2] == '_') {
                dialect[3] = '.';
                dialect[4] = '.';
        }


        /* en_US.ISO8859-1 -> en */
        strlcpy(lang_abk, lang, sizeof(lang_abk));
        if (strlen(lang_abk) >= 3 && lang_abk[2] == '_')
                lang_abk[2] = '\0';

        fprintf(stderr, "lang_default = %s\n", lang_default);
        fprintf(stderr, "dialect = %s\n", dialect);
        fprintf(stderr, "lang_abk = %s\n", lang_abk);

        fp = fopen(filename, "r");
        if (fp) {
                int matches;
                while (fgets(buffer, sizeof(buffer), fp)) {
                        p = buffer;
                        if (p[0] == '#')
                                continue;

                        while (isspace(*p))
                                p++;

                        if (*p == '\0')
                                continue;

                        /* Parse input, removing newline */
                        matches = sscanf(p, "%64[^:]:%64[^:]:%256[^:\n]", 
                            keym, lng, desc);
                        if (matches == 3) {
                                if (strcmp(keym, "FONT") != 0 &&
                                    strcmp(keym, "MENU") != 0 &&
                                    strcmp(keym, "TITLE") != 0) {
                                        /* Check file exists & is readable */
                                        if (check_file(keym) == -1)
                                                continue;
                                }
                        }

                        if (show) {
                                /*
                                 * Take note of supported languages, which
                                 * might be in a comma-delimited list
                                 */
                                char *tmp = strdup(lng);
                                char *delim = tmp;

                                for (delim = tmp; ; ) {
                                        char ch = *delim++;
                                        if (ch == ',' || ch == '\0') {
                                                delim[-1] = '\0';
                                                if (!sl_find(lang_list, tmp))
                                                        sl_add(lang_list, tmp);
                                                if (ch == '\0')
                                                        break;
                                                tmp = delim;
                                        }
                                }
                        }
                        /* Set empty language to default language */
                        if (lng[0] == '\0')
                                lg = lang_default;
                        else
                                lg = lng;


                        /* 4) Your choice if it exists
                         * 3) Long match eg. en_GB.ISO8859-1 is equal to
                         *      en_..\.ISO8859-1
                         * 2) short match 'de'
                         * 1) default langlist 'en'
                         * 0) any language
                         *
                         * Language may be a comma separated list
                         * A higher match overwrites a lower
                         * A later entry overwrites a previous if it exists
                         *     twice in the database
                         */

                        /* Check for favoured language */
                        km = get_keymap(keym);
                        mark = (km) ? km->mark : 0;

                        if (find_token(lg, lang))
                                add_keymap(desc, 4, keym);
                        else if (mark <= 3 && find_token(lg, dialect))
                                add_keymap(desc, 3, keym);
                        else if (mark <= 2 && find_token(lg, lang_abk))
                                add_keymap(desc, 2, keym);
                        else if (mark <= 1 && find_token(lg, lang_default))
                                add_keymap(desc, 1, keym);
                        else if (mark <= 0)
                                add_keymap(desc, 0, keym);
                }
                fclose(fp);

        } else
                fprintf(stderr, "Could not open %s for reading\n", filename);

        if (show) {
                qsort(lang_list->sl_str, lang_list->sl_cur, sizeof(char*),
                    compare_lang);
                printf("Currently supported languages: ");
                for (i=0; i< (int) lang_list->sl_cur; i++)
                        printf("%s ", lang_list->sl_str[i]);
                puts("");
                exit(0);
        }

        km = get_keymap("TITLE");
        if (km)
                /* Take note of dialog title */
                title = strdup(km->desc);
        km = get_keymap("MENU");
        if (km)
                /* Take note of menu title */
                menu = strdup(km->desc);
        km = get_keymap("FONT");
        if (km)
                /* Take note of language font */
                font = strdup(km->desc);

        /* Remove unwanted items from list */
        remove_keymap("FONT");
        remove_keymap("MENU");
        remove_keymap("TITLE");

        /* Look for keymaps not in database */
        dirp = opendir(dir);
        if (dirp) {
                while ((dp = readdir(dirp)) != NULL) {
                        const char *ext = get_extension(dp->d_name);
                        if (ext) {
                                if ((!strcmp(ext, ".fnt") ||
                                    !strcmp(ext, ".kbd")) &&
                                    !get_keymap(dp->d_name)) {
                                        char *q;

                                        /* Remove any .fnt or .kbd extension */
                                        q = strdup(dp->d_name);
                                        *(get_extension(q)) = '\0';
                                        add_keymap(q, 0, dp->d_name);
                                        free(q);

                                        if (verbose)
                                                fprintf(stderr,
                                                    "'%s' not in database\n",
                                                    dp->d_name);
                                }
                        }
                }
                closedir(dirp);
        } else
                fprintf(stderr, "Could not open directory '%s'\n", dir);

        /* Sort items in keymap */
        num_keymaps = get_num_keymaps();

        km_sorted = (struct keymap **)
            malloc(num_keymaps*sizeof(struct keymap *));

        /* Make array of pointers to items in hash */
        items = 0;
        SLIST_FOREACH(km, &head, entries)
                km_sorted[items++] = km;

        /* Change '8x8' to '8x08' so sort works as we might expect... */
        kludge_desc(km_sorted, num_keymaps);

        qsort(km_sorted, num_keymaps, sizeof(struct keymap *), compare_keymap);

        /* ...change back again */
        unkludge_desc(km_sorted, num_keymaps);

        if (print) {
                for (i=0; i<num_keymaps; i++)
                        printf("%s\n", km_sorted[i]->desc);
                exit(0);
        }

        show_dialog(km_sorted, num_keymaps);

        free(km_sorted);
}

/*
 * Display usage information and exit
 */
static void
usage(void)
{

        fprintf(stderr, "usage: %s\t[-K] [-V] [-d|-default] [-h|-help] "
            "[-l|-lang language]\n\t\t[-p|-print] [-r|-restore] [-s|-show] "
            "[-v|-verbose]\n", program);
        exit(1);
}

static void
parse_args(int argc, char **argv)
{
        int i;

        for (i=1; i<argc; i++) {
                if (argv[i][0] != '-')
                        usage();
                else if (!strcmp(argv[i], "-help") || !strcmp(argv[i], "-h"))
                        usage();
                else if (!strcmp(argv[i], "-verbose") || !strcmp(argv[i], "-v"))
                        verbose = 1;
                else if (!strcmp(argv[i], "-lang") || !strcmp(argv[i], "-l"))
                        if (i + 1 == argc)
                                usage();
                        else
                                lang = argv[++i];
                else if (!strcmp(argv[i], "-default") || !strcmp(argv[i], "-d"))
                        lang = lang_default;
                else if (!strcmp(argv[i], "-show") || !strcmp(argv[i], "-s"))
                        show = 1;
                else if (!strcmp(argv[i], "-print") || !strcmp(argv[i], "-p"))
                        print = 1;
                else if (!strcmp(argv[i], "-restore") ||
                    !strcmp(argv[i], "-r")) {
                        vidcontrol(font_current);
                        exit(0);
                } else if (!strcmp(argv[i], "-K"))
                        dir = keymapdir;
                else if (!strcmp(argv[i], "-V"))
                        dir = fontdir;
                else
                        usage();
        }
}

/*
 * A front-end for the 'vidfont' and 'kbdmap' programs.
 */
int
main(int argc, char **argv)
{

        x11 = system("kbdcontrol -d >/dev/null");

        if (x11) {
                fprintf(stderr, "You are not on a virtual console - "
                                "expect certain strange side-effects\n");
                sleep(2);
        }

        using_vt = check_vt();
        if (using_vt == 0) {
                keymapdir = DEFAULT_SC_KEYMAP_DIR;
                fontdir = DEFAULT_SC_FONT_DIR;
                font_default = DEFAULT_SC_FONT;
        }

        SLIST_INIT(&head);

        lang = get_locale();

        program = extract_name(argv[0]);

        font_current = get_font();
        if (font_current == NULL)
                font_current = font_default;

        if (strcmp(program, "kbdmap"))
                dir = fontdir;
        else
                dir = keymapdir;

        /* Parse command line arguments */
        parse_args(argc, argv);

        /* Read and display options */
        menu_read();

        return 0;
}