protected function parsePattern($pattern)
    {
        $currentPos      = 0;
        $length          = strlen($pattern);
        $tokens          = [];
        $level           = 0;
        $quotedDelimiter = preg_quote($this->delimiter);

        while ($currentPos < $length) {
            preg_match('(\G(?P<literal>[^:{\[\]]*)(?P<token>[:\[\]]|$))', $pattern, $matches, 0, $currentPos);

            $currentPos += strlen($matches[0]);

            if (!empty($matches['literal'])) {
                $tokens[] = ['literal', $matches['literal']];
            }

            if ($matches['token'] === ':') {
                if (!preg_match(
                    '(\G(?P<name>[^:' . $quotedDelimiter . '{\[\]]+)(?:{(?P<delimiters>[^}]+)})?:?)',
                    $pattern,
                    $matches,
                    0,
                    $currentPos
                )) {
                    throw new Exception\RuntimeException('Found empty parameter name');
                }

                $tokens[] = [
                    'parameter',
                    $matches['name'],
                    isset($matches['delimiters']) ? $matches['delimiters'] : null
                ];

                $currentPos += strlen($matches[0]);
            } elseif ($matches['token'] === '[') {
                $tokens[] = ['optional-start'];
                $level++;
            } elseif ($matches['token'] === ']') {
                $tokens[] = ['optional-end'];
                $level--;

                if ($level < 0) {
                    throw new Exception\RuntimeException('Found closing bracket without matching opening bracket');
                }
            } else {
                break;
            }
        }

        if ($level > 0) {
            throw new Exception\RuntimeException('Found unbalanced brackets');
        }

        return $tokens;
    }