Date._pad = function(num, len) {
    for (var i = 1; i <= len; i++)
        if (num < Math.pow(10, i))
            return new Array(len-i+1).join(0) + num;
    return num;
};
Date.prototype.format = function(format) {
    if (format.indexOf('%%') > -1) { // a literal `%' character
        format = format.split('%%');
        for (var i = 0; i < format.length; i++)
            format[i] = this.format(format[i]);
        return format.join('%');
    }
    format = format.replace(/%D/g, '%m/%d/%y'); // same as %m/%d/%y
    format = format.replace(/%r/g, '%I:%M:%S %p'); // time in a.m. and p.m. notation
    format = format.replace(/%R/g, '%H:%M:%S'); // time in 24 hour notation
    format = format.replace(/%T/g, '%H:%M:%S'); // current time, equal to %H:%M:%S
    var dateObj = this;
    return format.replace(/%([aAbhBcCdegGHIjmMnpStuUVWwyYzZ])/g, function(match0, match1) {
        return dateObj.format_callback(match0, match1);
    });
}
Date.prototype.format_callback = function(match0, match1) {
    switch (match1) {
        case 'a': // abbreviated weekday name according to the current locale
            return Date._l10n.days[this.getDay()].substr(0,3);
        case 'A': // full weekday name according to the current locale
            return Date._l10n.days[this.getDay()];
        case 'b':
        case 'h': // abbreviated month name according to the current locale
            return Date._l10n.months[this.getMonth()].substr(0,3);
        case 'B': // full month name according to the current locale
            return Date._l10n.months[this.getMonth()];
        case 'c': // preferred date and time representation for the current locale
            return this.toLocaleString();
        case 'C': // century number (the year divided by 100 and truncated to an integer, range 00 to 99)
            return Math.floor(this.getFullYear() / 100);
        case 'd': // day of the month as a decimal number (range 01 to 31)
            return Date._pad(this.getDate(), 2);
        case 'e': // day of the month as a decimal number, a single digit is preceded by a space (range ' 1' to '31')
            return Date._pad(this.getDate(), 2);
        /*case 'g': // like %G, but without the century
            return ;
        case 'G': // The 4-digit year corresponding to the ISO week number (see %V). This has the same format and value as %Y, except that if the ISO week number belongs to the previous or next year, that year is used instead
            return ;*/
        case 'H': // hour as a decimal number using a 24-hour clock (range 00 to 23)
            return Date._pad(this.getHours(), 2);
        case 'I': // hour as a decimal number using a 12-hour clock (range 01 to 12)
            return Date._pad(this.getHours() % 12, 2);
        case 'j': // day of the year as a decimal number (range 001 to 366)
            return Date._pad(this.getMonth() * 30 + Math.ceil(this.getMonth() / 2) + this.getDay() - 2 * (this.getMonth() > 1) + (!(this.getFullYear() % 400) || (!(this.getFullYear() % 4) && this.getFullYear() % 100)), 3);
        case 'm': // month as a decimal number (range 01 to 12)
            return Date._pad(this.getMonth() + 1, 2);
        case 'M': // minute as a decimal number
            return Date._pad(this.getMinutes(), 2);
        case 'n': // newline character
            return '\n';
        case 'p': // either `am' or `pm' according to the given time value, or the corresponding strings for the current locale
            return this.getHours() < 12 ? 'am' : 'pm';
        case 'S': // second as a decimal number
            return Date._pad(this.getSeconds(), 2);
        case 't': // tab character
            return '\t';
        case 'u': // weekday as a decimal number [1,7], with 1 representing Monday
            return this.getDay() || 7;
        /*case 'U': // week number of the current year as a decimal number, starting with the first Sunday as the first day of the first week
            return ;
        case 'V': // The ISO 8601:1988 week number of the current year as a decimal number, range 01 to 53, where week 1 is the first week that has at least 4 days in the current year, and with Monday as the first day of the week. (Use %G or %g for the year component that corresponds to the week number for the specified timestamp.)
            return ;
        case 'W': // week number of the current year as a decimal number, starting with the first Monday as the first day of the first week
            return ;*/
        case 'w': // day of the week as a decimal, Sunday being 0
            return this.getDay();
        case 'y': // year as a decimal number without a century (range 00 to 99)
            return this.getFullYear().toString().substr(2);
        case 'Y': // year as a decimal number including the century
            return this.getFullYear();
        /*case 'z':
        case 'Z': // time zone or name or abbreviation
            return ;*/
        default:
            return match0;
    }
}
  
  function updateClock() {

    var clientTime = new Date();
    var currentTime = new Date();
    var timeFormat = "%d/%m/%Y %H:%M:%S";
    var timeOffset = +7 * 60 * 60 * 1000;
    var timeZone = "WIB";
    currentTime.setTime(clientTime.getTime() + timeOffset);
    
    var currentHours = currentTime.getUTCHours();
    var currentMinutes = currentTime.getUTCMinutes();
    var currentSeconds = currentTime.getUTCSeconds();
    var currentMonth = currentTime.getUTCMonth();
    var currentDate = currentTime.getUTCDate();
    var currentDay = currentTime.getUTCDay();
    var currentYear = currentTime.getUTCFullYear();    
    var Now = new Date(currentYear, currentMonth, currentDate, currentHours, currentMinutes, currentSeconds);
    
    var output = Now.format(timeFormat);
    document.getElementById("egLocalTime").innerHTML = output + ' ' + timeZone;
  
}

window.onload = function() {
    updateClock();
    setInterval(updateClock, 1000);
}