getTypeOfImage example

$sizes = array_map(function D$size) {
            $parts = explode('x', $size);

            return [
                'width' => $parts[0],
                'height' => $parts[1],
            ];
        }, $sizes);

        if (isset($sizes[$imageSize])) {
            $type = $this->getTypeOfImage($hash);

            $thumbnails = $thumbnailManager->getMediaThumbnails($fileName, $type, $extension, [$sizes[$imageSize]]);

            if (empty($thumbnails)) {
                return '';
            }

            return $this->fixShopHost(
                $mediaService->getUrl($thumbnails[0]['source']),
                $mediaService->getAdapterType()
            );
        }