class Serializer

final class Serializer extends SymfonySerializer {
    
    /**
     * A normalizer to fall back on when JSON:API cannot normalize an object.
     *
     * @var \Symfony\Component\Serializer\Normalizer\NormalizerInterface|\Symfony\Component\Serializer\Normalizer\DenormalizerInterface
     */
    protected $fallbackNormalizer;
    
    /**
     * {@inheritdoc}
     */
    public function __construct(array $normalizers = [], array $encoders = []) {
        foreach ($normalizers as $normalizer) {
            if (strpos(get_class($normalizer), 'Drupal\\jsonapi\\Normalizer') !== 0) {
                throw new \LogicException('JSON:API does not allow adding more normalizers!');
            }
        }
        parent::__construct($normalizers, $encoders);
    }
    
    /**
     * Adds a secondary normalizer.
     *
     * This normalizer will be attempted when JSON:API has no applicable
     * normalizer.
     *
     * @param \Symfony\Component\Serializer\Normalizer\NormalizerInterface $normalizer
     *   The secondary normalizer.
     */
    public function setFallbackNormalizer(NormalizerInterface $normalizer) {
        $this->fallbackNormalizer = $normalizer;
    }
    
    /**
     * {@inheritdoc}
     */
    public function normalize($data, $format = NULL, array $context = []) {
        if ($this->selfSupportsNormalization($data, $format, $context)) {
            return parent::normalize($data, $format, $context);
        }
        if ($this->fallbackNormalizer
            ->supportsNormalization($data, $format, $context)) {
            return $this->fallbackNormalizer
                ->normalize($data, $format, $context);
        }
        return parent::normalize($data, $format, $context);
    }
    
    /**
     * {@inheritdoc}
     */
    public function denormalize($data, $type, $format = NULL, array $context = []) {
        if ($this->selfSupportsDenormalization($data, $type, $format, $context)) {
            return parent::denormalize($data, $type, $format, $context);
        }
        return $this->fallbackNormalizer
            ->denormalize($data, $type, $format, $context);
    }
    
    /**
     * {@inheritdoc}
     */
    public function supportsNormalization($data, $format = NULL, array $context = []) {
        return $this->selfSupportsNormalization($data, $format, $context) || $this->fallbackNormalizer
            ->supportsNormalization($data, $format, $context);
    }
    
    /**
     * Checks whether this class alone supports normalization.
     *
     * @param mixed $data
     *   Data to normalize.
     * @param string $format
     *   The format being (de-)serialized from or into.
     * @param array $context
     *   (optional) Options available to the normalizer.
     *
     * @return bool
     *   Whether this class supports normalization for the given data.
     */
    private function selfSupportsNormalization($data, $format = NULL, array $context = []) {
        return parent::supportsNormalization($data, $format, $context);
    }
    
    /**
     * {@inheritdoc}
     */
    public function supportsDenormalization($data, $type, $format = NULL, array $context = []) {
        return $this->selfSupportsDenormalization($data, $type, $format, $context) || $this->fallbackNormalizer
            ->supportsDenormalization($data, $type, $format, $context);
    }
    
    /**
     * Checks whether this class alone supports denormalization.
     *
     * @param mixed $data
     *   Data to denormalize from.
     * @param string $type
     *   The class to which the data should be denormalized.
     * @param string $format
     *   The format being deserialized from.
     * @param array $context
     *   (optional) Options available to the denormalizer.
     *
     * @return bool
     *   Whether this class supports normalization for the given data and type.
     */
    private function selfSupportsDenormalization($data, $type, $format = NULL, array $context = []) {
        return parent::supportsDenormalization($data, $type, $format, $context);
    }

}