package net.minecraft.client.resources.model.cuboid;

import com.google.common.annotations.VisibleForTesting;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParseException;
import java.io.Reader;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.client.resources.model.UnbakedModel;
import net.minecraft.client.resources.model.geometry.UnbakedGeometry;
import net.minecraft.client.resources.model.sprite.TextureSlots;
import net.minecraft.resources.Identifier;
import net.minecraft.util.GsonHelper;
import org.jspecify.annotations.Nullable;

@Environment(EnvType.CLIENT)
public record CuboidModel(
	@Nullable UnbakedGeometry geometry,
	@Nullable UnbakedModel.GuiLight guiLight,
	@Nullable Boolean ambientOcclusion,
	@Nullable ItemTransforms transforms,
	TextureSlots.Data textureSlots,
	@Nullable Identifier parent
) implements UnbakedModel {
	@VisibleForTesting
	static final Gson GSON = new GsonBuilder()
		.registerTypeAdapter(CuboidModel.class, new CuboidModel.Deserializer())
		.registerTypeAdapter(CuboidModelElement.class, new CuboidModelElement.Deserializer())
		.registerTypeAdapter(CuboidFace.class, new CuboidFace.Deserializer())
		.registerTypeAdapter(ItemTransform.class, new ItemTransform.Deserializer())
		.registerTypeAdapter(ItemTransforms.class, new ItemTransforms.Deserializer())
		.create();

	public static CuboidModel fromStream(final Reader reader) {
		return GsonHelper.fromJson(GSON, reader, CuboidModel.class);
	}

	@Environment(EnvType.CLIENT)
	public static class Deserializer implements JsonDeserializer<CuboidModel> {
		public CuboidModel deserialize(final JsonElement json, final Type typeOfT, final JsonDeserializationContext context) throws JsonParseException {
			JsonObject object = json.getAsJsonObject();
			UnbakedGeometry elements = this.getElements(context, object);
			String parentName = this.getParentName(object);
			TextureSlots.Data textureMap = this.getTextureMap(object);
			Boolean hasAmbientOcclusion = this.getAmbientOcclusion(object);
			ItemTransforms transforms = null;
			if (object.has("display")) {
				JsonObject display = GsonHelper.getAsJsonObject(object, "display");
				transforms = context.deserialize(display, ItemTransforms.class);
			}

			UnbakedModel.GuiLight guiLight = null;
			if (object.has("gui_light")) {
				guiLight = UnbakedModel.GuiLight.getByName(GsonHelper.getAsString(object, "gui_light"));
			}

			Identifier parentLocation = parentName.isEmpty() ? null : Identifier.parse(parentName);
			return new CuboidModel(elements, guiLight, hasAmbientOcclusion, transforms, textureMap, parentLocation);
		}

		private TextureSlots.Data getTextureMap(final JsonObject object) {
			if (object.has("textures")) {
				JsonObject texturesObject = GsonHelper.getAsJsonObject(object, "textures");
				return TextureSlots.parseTextureMap(texturesObject);
			} else {
				return TextureSlots.Data.EMPTY;
			}
		}

		private String getParentName(final JsonObject object) {
			return GsonHelper.getAsString(object, "parent", "");
		}

		@Nullable
		protected Boolean getAmbientOcclusion(final JsonObject object) {
			return object.has("ambientocclusion") ? GsonHelper.getAsBoolean(object, "ambientocclusion") : null;
		}

		@Nullable
		protected UnbakedGeometry getElements(final JsonDeserializationContext context, final JsonObject object) {
			if (!object.has("elements")) {
				return null;
			} else {
				List<CuboidModelElement> elements = new ArrayList();

				for (JsonElement element : GsonHelper.getAsJsonArray(object, "elements")) {
					elements.add((CuboidModelElement)context.deserialize(element, CuboidModelElement.class));
				}

				return new UnbakedCuboidGeometry(elements);
			}
		}
	}
}