@VisibleForTesting
  List<Image> getCachedBaseImages()
      throws IOException, CacheCorruptedException, BadContainerConfigurationFormatException,
          LayerCountMismatchException, UnlistedPlatformInManifestListException,
          PlatformNotFoundInBaseImageException {
    ImageReference baseImage = buildContext.getBaseImageConfiguration().getImage();
    Optional<ImageMetadataTemplate> metadata =
        buildContext.getBaseImageLayersCache().retrieveMetadata(baseImage);
    if (!metadata.isPresent()) {
      return Collections.emptyList();
    }

    ManifestTemplate manifestList = metadata.get().getManifestList();
    List<ManifestAndConfigTemplate> manifestsAndConfigs = metadata.get().getManifestsAndConfigs();

    if (manifestList == null) {
      Verify.verify(manifestsAndConfigs.size() == 1);
      ManifestAndConfigTemplate manifestAndConfig = manifestsAndConfigs.get(0);
      Optional<Image> cachedImage = getBaseImageIfAllLayersCached(manifestAndConfig, true);
      if (!cachedImage.isPresent()) {
        return Collections.emptyList();
      }
      return Collections.singletonList(cachedImage.get());
    }

    // Manifest list cached. Identify matching platforms and check if all of them are cached.
    ImmutableList.Builder<Image> images = ImmutableList.builder();
    for (Platform platform : buildContext.getContainerConfiguration().getPlatforms()) {
      String manifestDigest =
          lookUpPlatformSpecificImageManifest((ManifestListTemplate) manifestList, platform);

      Optional<ManifestAndConfigTemplate> manifestAndConfigFound =
          manifestsAndConfigs.stream()
              .filter(entry -> manifestDigest.equals(entry.getManifestDigest()))
              .findFirst();
      if (!manifestAndConfigFound.isPresent()) {
        return Collections.emptyList();
      }
      Optional<Image> cachedImage =
          getBaseImageIfAllLayersCached(manifestAndConfigFound.get(), false);
      if (!cachedImage.isPresent()) {
        return Collections.emptyList();
      }
      images.add(cachedImage.get());
    }
    return images.build();
  }
@Test
  public void testGetCachedBaseImages_emptyCache()
      throws InvalidImageReferenceException, IOException, CacheCorruptedException,
          UnlistedPlatformInManifestListException, PlatformNotFoundInBaseImageException,
          BadContainerConfigurationFormatException, LayerCountMismatchException {
    ImageReference imageReference = ImageReference.parse("cat");
    Mockito.when(buildContext.getBaseImageConfiguration())
        .thenReturn(ImageConfiguration.builder(imageReference).build());
    Mockito.when(cache.retrieveMetadata(imageReference)).thenReturn(Optional.empty());

    Assert.assertEquals(Arrays.asList(), pullBaseImageStep.getCachedBaseImages());
  }