class AbstractSurrogateFragmentRenderer

abstract class AbstractSurrogateFragmentRenderer extends RoutableFragmentRenderer {
    
    /**
     * The "fallback" strategy when surrogate is not available should always be an
     * instance of InlineFragmentRenderer.
     *
     * @param FragmentRendererInterface $inlineStrategy The inline strategy to use when the surrogate is not supported
     */
    public function __construct(?SurrogateInterface $surrogate, FragmentRendererInterface $inlineStrategy, ?UriSigner $signer = null) {
    }
    
    /**
     * Note that if the current Request has no surrogate capability, this method
     * falls back to use the inline rendering strategy.
     *
     * Additional available options:
     *
     *  * alt: an alternative URI to render in case of an error
     *  * comment: a comment to add when returning the surrogate tag
     *  * absolute_uri: whether to generate an absolute URI or not. Default is false
     *
     * Note, that not all surrogate strategies support all options. For now
     * 'alt' and 'comment' are only supported by ESI.
     *
     * @see Symfony\Component\HttpKernel\HttpCache\SurrogateInterface
     */
    public function render(string|ControllerReference $uri, Request $request, array $options = []) : Response {
        if (!$this->surrogate || !$this->surrogate
            ->hasSurrogateCapability($request)) {
            $request->attributes
                ->set('_check_controller_is_allowed', true);
            if ($uri instanceof ControllerReference && $this->containsNonScalars($uri->attributes)) {
                throw new \InvalidArgumentException('Passing non-scalar values as part of URI attributes to the ESI and SSI rendering strategies is not supported. Use a different rendering strategy or pass scalar values.');
            }
            return $this->inlineStrategy
                ->render($uri, $request, $options);
        }
        $absolute = $options['absolute_uri'] ?? false;
        if ($uri instanceof ControllerReference) {
            $uri = $this->generateSignedFragmentUri($uri, $request, $absolute);
        }
        $alt = $options['alt'] ?? null;
        if ($alt instanceof ControllerReference) {
            $alt = $this->generateSignedFragmentUri($alt, $request, $absolute);
        }
        $tag = $this->surrogate
            ->renderIncludeTag($uri, $alt, $options['ignore_errors'] ?? false, $options['comment'] ?? '');
        return new Response($tag);
    }
    private function generateSignedFragmentUri(ControllerReference $uri, Request $request, bool $absolute) : string {
        return (new FragmentUriGenerator($this->fragmentPath, $this->signer))
            ->generate($uri, $request, $absolute);
    }
    private function containsNonScalars(array $values) : bool {
        foreach ($values as $value) {
            if (\is_scalar($value) || null === $value) {
                continue;
            }
            if (!\is_array($value) || $this->containsNonScalars($value)) {
                return true;
            }
        }
        return false;
    }

}