Knockout-Lite/app/BbCode/Tag/Unknown.php

<?php

namespace App\BbCode\Tag;

use Knockout\BbCode\Tag\TagInterface;
use Knockout\BbCode\Tokenizer\Tag as TokenTag;

class Unknown implements TagInterface
{

    public function format(TokenTag $tokenTag) : string
    {
        $formattedString = "[{$tokenTag->getType()}";

        if ($tokenTag->getArgument()) {
            $formattedString .= " {$tokenTag->getArgument()}";
        }

        $formattedString .= "]{$tokenTag->getText()}[/{$tokenTag->getType()}]";
        return $formattedString;
    }

    public function getName(): string
    {
        return '';
    }

    public function getOriginalText(TokenTag $tokenTag): string
    {
        return "[{$tokenTag->getType()}]{$tokenTag->getText()}[/{$tokenTag->getType()}]";
    }
}