/*
 * lang.c - determines language, handles translations
 *
 * Erik Troan <ewt@redhat.com>
 * Matt Wilson <msw@redhat.com>
 * Michael Fulbright <msf@redhat.com>
 * Jeremy Katz <katzj@redhat.com>
 *
 * Copyright 1997 - 2003 Red Hat, Inc.
 *
 * This software may be freely redistributed under the terms of the GNU
 * General Public License.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <alloca.h>
#include <errno.h>
#include <fcntl.h>
#include <netinet/in.h>
#include <newt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <unistd.h>

#include "loader.h"
#include "lang.h"
#include "log.h"
#include "loadermisc.h"
#include "windows.h"

#include "../isys/stubs.h"
#include "../isys/cpio.h"

static int startBterm(int flags);

struct aString {
    unsigned int hash;
    short length;
    char * str;
} ;

struct aString * strings = NULL;
int numStrings = 0, allocedStrings = 0;

static char * topLineWelcome = N_("Welcome to %s");
static char * bottomHelpLine = N_("  <Tab>/<Alt-Tab> between elements  | <Space> selects | <F12> next screen ");

static int aStringCmp(const void * a, const void * b) {
    const struct aString * first = a;
    const struct aString * second = b;

    if (first->hash < second->hash)
        return -1;
    else if (first->hash == second->hash)
        return 0;

    return 1;
}

char * translateString(char * str) {
    unsigned int sum = 0, xor = 0;
    int len = 0;
    char * chptr;
    struct aString * match;
    struct aString key;

    for (chptr = str; *chptr; chptr++) {
        sum += *chptr;
        xor ^= *chptr;
        len++;
    }

    key.hash = (sum << 16) | ((xor & 0xFF) << 8) | (len & 0xFF);
    match = bsearch(&key, strings, numStrings, sizeof(*strings), aStringCmp);
    if (!match)
        return str;

    return match->str;
}

static struct langInfo * languages = NULL;
static int numLanguages = 0;

static void loadLanguageList(int flags) {
    char * file = FL_TESTING(flags) ? "../lang-table" :
                    "/etc/lang-table";
    FILE * f;
    char line[256];
    char name[256], key[256], font[256], map[256], code[256],
         keyboard[256], timezone[256], instlang[256];
    int lineNum = 0;

    f = fopen(file, "r");
    if (!f) {
        newtWinMessage(_("Error"), _("OK"), "cannot open %s: %s",
                       file, strerror (errno));
        return;
    }

    while (fgets(line, sizeof(line), f)) {
        lineNum++;
        languages = realloc(languages, sizeof(*languages) * (numLanguages + 1));
        if (sscanf(line, "%s %s %s %s %s %s %s %s\n", name, key, font, map,
                   code, keyboard, timezone, instlang) != 8) {
            logMessage("bad line %d in lang-table", lineNum);
        } else {
            languages[numLanguages].lang = strdup(name);
            languages[numLanguages].key = strdup(key);
            languages[numLanguages].font = strdup(font);
            languages[numLanguages].map = strdup(map);
            languages[numLanguages].lc_all = strdup(code);
            languages[numLanguages].keyboard = strdup(keyboard);
            languages[numLanguages].instlang = strdup(instlang);
            numLanguages++;
        }
    }
    fclose(f);
}

int getLangInfo(struct langInfo ** langs, int flags) {
    if (!languages)
	loadLanguageList(flags);

    *langs = languages;
    return numLanguages;
}

void loadLanguage (char * file, int flags) {
    char filename[200];
    gzFile stream;
    int fd, hash, rc;
    char * key = getenv("LANGKEY");

    if (strings) {
	free(strings), strings = NULL;
	numStrings = allocedStrings = 0;
    }
    
    /* english requires no files */
    if (!strcmp(key, "en"))
        return;

    if (!file) {
        file = filename;
        if (FL_TESTING(flags))
            sprintf(filename, "loader.tr");
        else
            sprintf(filename, "/etc/loader.tr");
    }

    stream = gunzip_open(file);

    if (!stream) {
        newtWinMessage("Error", "OK", "Translation for %s is not available.  "
                       "The Installation will proceed in English.", key);
        return ;
    }
    
    sprintf(filename, "%s.tr", key);

    rc = installCpioFile(stream, filename, "/tmp/translation", 1);
    gunzip_close(stream);

    if (rc || access("/tmp/translation", R_OK)) {
        newtWinMessage("Error", "OK", "Cannot get translation file %s.\n", 
                        filename);
        return;
    }
    
    fd = open("/tmp/translation", O_RDONLY);
    if (fd < 0) {
        newtWinMessage("Error", "OK", "Failed to open /tmp/translation: %s\n", 
                        strerror(errno));
        return;
    }

    while (read(fd, &hash, 4) == 4) {
        if (allocedStrings == numStrings) {
            allocedStrings += 10;
            strings = realloc(strings, sizeof(*strings) * allocedStrings);
        }

        strings[numStrings].hash = ntohl(hash);
        read(fd, &strings[numStrings].length, 2);
        strings[numStrings].length = ntohs(strings[numStrings].length);
        strings[numStrings].str = malloc(strings[numStrings].length + 1);
        read(fd, strings[numStrings].str, strings[numStrings].length);
        strings[numStrings].str[strings[numStrings].length] = '\0';
        numStrings++;
    }

    close(fd);
    unlink("/tmp/translation");

    qsort(strings, numStrings, sizeof(*strings), aStringCmp);
}


/* give the index of the language to set to -- sets the appropriate
 * lang variables if we have a font.
 *
 * ASSUMPTION: languages exists
 */
static void setLangEnv (int i, int flags) {
    if (i > numLanguages)
        return;

    logMessage("setting language to %s", languages[i].lc_all);
    if (!strcmp(languages[i].font, "None"))
        return;

    setenv("LANG", languages[i].instlang, 1);
    setenv("LANGKEY", languages[i].key, 1);
    setenv("LINGUAS", languages[i].instlang, 1);
    loadLanguage (NULL, flags);
}

/* choice is the index of the chosen language in languages */
static int setupLanguage(int choice, int flags) {
    char * buf;
    int i;

    logMessage("going to set language to %s", languages[choice].lc_all);
    /* load the language only if it is displayable */
    if (!strcmp(languages[choice].font, "bterm") && startBterm(flags)) {
        if (FL_KICKSTART(flags)) return 0;

	newtWinMessage("Language Unavailable", "OK", 
		       "%s display is unavailable in text mode.  The "
		       "installation will continue in English until the "
		       "display of %s is possible.", languages[choice].lang,
		       languages[choice].lang);
	return 0;
    }
    
    setLangEnv (choice, flags);

    /* clear out top line */
    buf = alloca(80);
    for (i=0; i < 80; i++)
	buf[i] = ' ';
    newtDrawRootText(0, 0, buf);

    buf = sdupprintf(_(topLineWelcome), getProductName());
    newtDrawRootText(0, 0, buf);
    free(buf);
    newtPopHelpLine();
    newtPushHelpLine(_(bottomHelpLine));

    return 0;

}

/* this is pretty simple.  we want to break down the language specifier
 * into its short form (eg, en_US)
 */
static char * getLangShortForm(char * oldLang) {
    char * lang;
    char * c;
    
    lang = strdup(oldLang);

    c = strchr(lang, '@');
    if (c) {
        *c = '\0';
    }

    c = strchr(lang, '.');
    if (c) {
        *c = '\0';
    }

    return lang;
}

/* return the nick of a language -- eg en_US -> en */
static char * getLangNick(char * oldLang) {
    char * lang;
    char * c;
    
    lang = strdup(oldLang);

    c = strchr(lang, '_');
    if (c) {
        *c = '\0';
    }

    return lang;
}

int setLanguage (char * key, int flags) {
    int i;

    if (!languages) loadLanguageList(flags);

    for (i = 0; i < numLanguages; i++) {
        if (!strcmp(languages[i].lc_all, key)) {
            return setupLanguage(i, flags);
        }
    }

    /* we didn't specify anything that's exactly in the lang-table.  check
     * against short forms and nicks */
    for (i = 0; i < numLanguages; i++) {
        if (!strcmp(getLangShortForm(languages[i].lc_all), key)) {
            return setupLanguage(i, flags);
        }
    }

    for (i = 0; i < numLanguages; i++) {
        if (!strcmp(getLangNick(languages[i].lc_all), key)) {
            return setupLanguage(i, flags);
        }
    }

    logMessage("unable to set to requested language %s", key);
    return -1;
}

/* returns 0 on success, 1 on failure */
extern int bterm_main(int argc, char **argv);

static int startBterm(int flags) {
    char *args[4] = { "bterm", "-s", "-f", NULL };
    int rc;
    struct stat sb;

    /* assume that if we're already on a pty we can handle unicode */
    fstat(0, &sb);
    if (major(sb.st_rdev) == 3 || major(sb.st_rdev) == 136)
	return 0;

    if (FL_TESTING(flags))
	args[3] = "font.bgf.gz";	
    else
	args[3] = "/etc/font.bgf.gz";
    
    stopNewt();
    rc = bterm_main(4, args);
    startNewt(flags);
    return rc;
}

int chooseLanguage(char ** lang, int flags) {
    int choice = 0;
    char ** langs;
    int i;
    int english = 0;
    int current = -1;
    char * currentLangName = getenv("LANG");
    int numLangs = 0;
    char * langPicked;

    if (!languages) loadLanguageList(flags);

    langs = alloca(sizeof(*langs) * (numLanguages + 1)); 

    for (i = 0; i < numLanguages; i++) {
        if (!strncmp(languages[i].key, "en", 2))
            english = numLangs;
        if (currentLangName &&
            !strcmp(languages[i].instlang, currentLangName))
            current = numLangs;

        langs[numLangs++] = languages[i].lang;
    }

    langs[numLangs] = NULL;

    if (current >= 0)
        choice = current;
    else
        choice = english;

    newtWinMenu(_("Choose a Language"),
                _("What language would you like to use during the "
                  "installation process?"), 40, 5, 5, 8,
                langs, &choice, _("OK"), NULL);

    langPicked = langs[choice];
    for (i = 0; i < numLanguages; i++) {
        if (!strcmp(langPicked, languages[i].lang)) {
            *lang = languages[i].lc_all;
            choice = i;
            break;
        }
    }

    /* this can't happen */
    if (i == numLanguages) abort();

    /* load the language only if it is displayable */
    if (!strcmp(languages[choice].font, "bterm") && startBterm(flags)) {
	newtWinMessage("Language Unavailable", "OK", 
		       "%s display is unavailable in text mode.  The "
		       "installation will continue in English until the "
		       "display of %s is possible.", languages[choice].lang,
		       languages[choice].lang);
	return 0;
    }

    setupLanguage(choice, flags);
    return 0;
}

void setKickstartLanguage(struct loaderData_s * loaderData, int argc, 
                          char ** argv, int * flagsPtr) {
    if (argc < 2) {
        logMessage("no argument passed to lang kickstart command");
        return;
    }

    loaderData->lang = argv[1];
    loaderData->lang_set = 1;
}