public function decodeInteger(string $data): int
    {
        $this->validateInput($data);

        $data = str_split($data);
        $data = array_map(function ($character) {
            return strpos($this->options["characters"], $character);
        }, $data);

        $converted = $this->baseConvert($data, 62, 10);
        return (integer) implode("", $converted);
    }