protected function convertArgs($step)
    {
        if ($step instanceof Operator) {
            $arguments = $step->getArguments();
        } else {
            $arguments = $step;
        }

        if (is_array($arguments)) {
            $values = [];
            foreach ($arguments as $key => $args) {
                if ($args instanceof Operator) {
                    if (is_string($key)) {
                        $values[$key] = [$this->cmd.$args->getOperatorName() => $this->convertArgs($args)];
                    } else {
                        $values[] = [$this->cmd.$args->getOperatorName() => $this->convertArgs($args)];
                    }
                } else {
                    if (is_string($key)) {
                        $values[$key] = $this->convertArgs($args);
                    } else {
                        $values[] = $args;
                    }
                }
            }

            return $values;

        } elseif ($arguments instanceof Operator) {
            return [$this->cmd.$arguments->getOperatorName() => $this->convertArgs($arguments)];
        } else {
            return $arguments;
        }
    }