Display Visitor's Local Time for IPV6

/****************************************************************************************************************/
/* Description: This snippet is provide simple way to help user display Visitor's Local Time.                   */
/*              suggestions for different city locations across the country.                                    */
/*              There are 1 steps in this snippet. For information, please visit IP2Location tutorial page at:  */
/* https://www.ip2location.com/tutorials/display-visitors-local-time-using-php-and-mysql-database               */
/****************************************************************************************************************/
/* You can obtain free IP2Location DB11 LITE database for IPv6 at                                               */
/*https://lite.ip2location.com/database/ip-country-region-city-latitude-longitude-zipcode-timezone              */

<?php

    // Replace this MYSQL server variables with actual configuration
    $mysql_server = "mysql_server.com";
    $mysql_user_name = "UserName";
    $mysql_user_pass = "Password";

    // Retrieve visitor IP address from server variable REMOTE_ADDR
    $ip = $_SERVER['REMOTE_ADDR'];

    // Convert IP address to IP number for querying database
    $ipno = Dot2LongIPv6($ip);

    // Connect to the database server
    $link = mysqli_connect($mysql_server, $mysql_user_name, $mysql_user_pass) or die("Could not connect to MySQL database");

    // Connect to the IP2Location database
    mysqli_select_db($link,"ip2location") or die("Could not select database");

    // SQL query string to match the recordset that the IP number fall between the valid range
    $query = "SELECT time_zone, country_code FROM ip2location_db11 WHERE $ipno <= ip_to LIMIT 1";

    // Execute SQL query
    $result = mysqli_query($link,$query) or die("IP2Location Query Failed");

    // Retrieve the recordset (only one)
    $row = mysqli_fetch_assoc($result);

    // Keep the time zone and country code as variables
    $country_code = $row['country_code'];
    $time_zone = $row['time_zone'];

    // Free recordset and close database connection
    mysqli_free_result($result);
    mysqli_close($link);

    $utc_time = gmdate("H:i:s");
    $utc_h = explode(':', $utc_time);

    if (strcmp($time_zone, "-") == 0) {
        $localdate = $utc_time;
    }
    else {
        $time = explode(':', $time_zone);

        if ($utc_h[0] + $time[0] < 0) {
            $hour = $utc_h[0] + 24 + $time[0];
        }
        elseif ($utc_h[0] + $time[0] >= 24) {
            $hour = $utc_h[0] + $time[0] - 24;
        }
        else {
            $hour = $utc_h[0] + $time[0];
        }

        $localdate = $hour . gmdate(":i:s");
    }

    date_default_timezone_set("Asia/Kuala_Lumpur");
    $date = date_create($localdate);
    echo 'Country Code: ' . $country_code . '<br />';
    echo 'Local Time: ' . date_format($date, "H:i:s"). '<br />';
    echo 'Server Time: ' . strftime("%H:%M:%S") . '<br />';
    echo 'UTC Time: ' . gmdate("H:i:s") . '<br />';

    // Function to convert IP address to IP number (IPv6)
    function Dot2LongIPv6 ($IPaddr) {
        $int = inet_pton($IPaddr);
        $bits = 15;
        $ipv6long = 0;
        while($bits >= 0){
            $bin = sprintf("%08b", (ord($int[$bits])));
            if($ipv6long){
                $ipv6long = $bin . $ipv6long;
            }
            else{
                $ipv6long = $bin;
            }
            $bits--;
        }
        $ipv6long = gmp_strval(gmp_init($ipv6long, 2), 10);
        return $ipv6long;
    }
?>