<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');

function getIPv4() {
    $ipv4 = '';
    if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
        $ipv4 = $_SERVER['HTTP_X_FORWARDED_FOR'];
    } else if (isset($_SERVER['HTTP_CLIENT_IP'])) {
        $ipv4 = $_SERVER['HTTP_CLIENT_IP'];
    } else {
        $ipv4 = $_SERVER['REMOTE_ADDR'];
    }
    return filter_var($ipv4, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) ? $ipv4 : '';
}

function getIPv6() {
    $ipv6 = '';
    if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
        $ips = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
        foreach ($ips as $ip) {
            if (filter_var(trim($ip), FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
                $ipv6 = trim($ip);
                break;
            }
        }
    } else if (isset($_SERVER['REMOTE_ADDR']) && filter_var($_SERVER['REMOTE_ADDR'], FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
        $ipv6 = $_SERVER['REMOTE_ADDR'];
    }
    return $ipv6;
}

echo json_encode([
    'ipv4' => getIPv4(),
    'ipv6' => getIPv6()
]);