model

public class TestModelLoader implements IModelGeometry<TestModelLoader> {

	final String key;
	final Map<String, BlockModel> modelMap;

	public TestModelLoader(String key, Map<String, BlockModel> modelMap) {

		this.key = key;
		this.modelMap = modelMap;
	}

	@Override
	public IBakedModel bake(IModelConfiguration owner, ModelBakery bakery, Function<Material, TextureAtlasSprite> spriteGetter, IModelTransform modelTransform, ItemOverrideList overrides, ResourceLocation modelLocation) {

		return new BakedModel(owner, modelTransform, modelLocation,
                spriteGetter.apply(owner.resolveTexture("particle")),
                owner.isSideLit(), bakery, owner.getOwnerModel(), bakery::getUnbakedModel, spriteGetter, key,
                Maps.transformEntries(modelMap, (k, v) -> v.bakeModel(bakery, v, spriteGetter, modelTransform, new ResourceLocation(modelLocation.getNamespace(), modelLocation.getPath() + "/" + k), owner.isSideLit()))
        );
	}

	@Override
	public Collection<Material> getTextures(IModelConfiguration owner, Function<ResourceLocation, IUnbakedModel> modelGetter, Set<Pair<String, String>> missingTextureErrors) {

		return null;

	}

	public static class BakedModel implements IBakedModel {

		private final boolean isSideLit;
		private final TextureAtlasSprite particle;
		private final IModelConfiguration owner;
		private IModelTransform modelTransform;
		private ResourceLocation modelLocation;
		private final ItemOverrideList overrides;

		public BakedModel(IModelConfiguration owner, IModelTransform modelTransform, ResourceLocation modelLocation, TextureAtlasSprite particle, boolean isSideLit, ModelBakery bakery, IUnbakedModel ownerModel, Function<ResourceLocation, IUnbakedModel> modelGetter, Function<Material, TextureAtlasSprite> textureGetter, String key, Map<String, IBakedModel> modelMap) {

			this.isSideLit = isSideLit;
			this.particle = particle;
			this.owner = owner;
			this.modelTransform = modelTransform;
			this.modelLocation = modelLocation;
			this.overrides = new ItemOverrideList(bakery, ownerModel, modelGetter, textureGetter, Collections.emptyList()) {

				final String nbtKey = key;
				final Map<String, IBakedModel> models = modelMap;

				@Nullable
				@Override
				public IBakedModel getModelWithOverrides(IBakedModel model, ItemStack stack, @Nullable World worldIn, @Nullable LivingEntity entityIn) {

					ImmutableList.Builder<Material> textures = ImmutableList.builder();

					textures.add(new Material(AtlasTexture.LOCATION_BLOCKS_TEXTURE, new ResourceLocation("block/test1")));
					textures.add(new Material(AtlasTexture.LOCATION_BLOCKS_TEXTURE, new ResourceLocation("block/test2")));
					textures.add(new Material(AtlasTexture.LOCATION_BLOCKS_TEXTURE, new ResourceLocation("block/test3")));

					ItemLayerModel model2 = new ItemLayerModel(textures.build());

					/**

					CompoundNBT tag = stack.getTag();
					INBT tagValue = (tag != null) ? tag.get(nbtKey) : null;

					String value = tagValue != null ? tagValue.getString() : null;

					if (value == null) {

						value = "";

					}

					return models.getOrDefault(value, null);

					**/

					return model2.bake(owner, bakery, textureGetter, modelTransform, overrides, modelLocation);

				}

			};

		}

		@Override
		public List<BakedQuad> getQuads(BlockState state, Direction side, Random rand) {

			return Collections.emptyList();

		}

		@Override
		public boolean isAmbientOcclusion() {

			return true;

		}

		@Override
		public boolean isGui3d() {

			return true;

		}

		@Override
		public boolean func_230044_c_() {

			return isSideLit;

		}

		@Override
		public boolean isBuiltInRenderer() {

			return false;

		}

		@Override
		public TextureAtlasSprite getParticleTexture() {

			return particle;

		}

		@Override
		public ItemOverrideList getOverrides() {

			return overrides;

		}

	}

	public static class Loader implements IModelLoader<TestModelLoader> {

		@Override
		public void onResourceManagerReload(IResourceManager resourceManager) {

		}

		@Override
		public TestModelLoader read(JsonDeserializationContext deserializationContext, JsonObject modelContents) {

			String key = JSONUtils.getString(modelContents, "tag");
            JsonObject obj = JSONUtils.getJsonObject(modelContents, "values");
            ImmutableMap.Builder<String, BlockModel> builder = ImmutableMap.<String, BlockModel>builder();
            for(Map.Entry<String, JsonElement> kv : obj.entrySet())
            {
                builder.put(kv.getKey(), deserializationContext.deserialize(kv.getValue(), BlockModel.class));
            }
            return new TestModelLoader(key, builder.build());

		}

	}

}