utils.php

<?php
function generateRandomString($length = 96)
{
    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $charactersLength = strlen($characters);
    $randomString = '';
    for ($i = 0; $i < $length; $i++) {
        $randomString .= $characters[rand(0, $charactersLength - 1)];
    }
    return $randomString;
}

function getClientIP(): string
{
    $keys = array('HTTP_CLIENT_IP', 'HTTP_X_FORWARDED_FOR', 'HTTP_X_FORWARDED', 'HTTP_FORWARDED_FOR', 'HTTP_FORWARDED', 'REMOTE_ADDR');
    foreach ($keys as $k) {
        if (!empty($_SERVER[$k]) && filter_var($_SERVER[$k], FILTER_VALIDATE_IP)) {
            return $_SERVER[$k];
        }
    }
    return false;
}

function format(string $string, array $values)
{
    foreach ($values as $key => $value) {
        $string = str_replace("{{{$key}}}", $value, $string);
    }
    return $string;
}