public function renderHelp()
    {
        $this->renderHeader();

        echo Line::begin('Usage:', Line::YELLOW)->nl();
        echo Line::begin()
            ->indent(2)
            ->text($this->getUsage())
            ->nl(2);

        // Options
        echo Line::begin('Options:', Line::YELLOW)->nl();
        echo Line::begin()
            ->indent(2)
            ->text('--help', Line::MAGENTA)
            ->to(21)
            ->text('-h', Line::MAGENTA)
            ->text('Display this help message.')
            ->nl(1);

        $attributes = $this->attributeNames();
        $help = $this->attributeHelp();

        sort($attributes);

        foreach ($attributes as $name) {
            echo Line::begin()
                ->indent(2)
                ->text("--$name", Line::MAGENTA)
                ->to(24)
                ->text(isset($help[$name]) ? $help[$name] : '')
                ->nl();
        }

        exit(0);
    }