package net.minecraft.client.renderer.texture;

import com.mojang.blaze3d.GpuFormat;
import com.mojang.blaze3d.buffers.GpuBufferSlice;
import com.mojang.blaze3d.platform.NativeImage;
import com.mojang.blaze3d.systems.GpuDevice;
import com.mojang.blaze3d.systems.RenderSystem;
import java.io.IOException;
import net.minecraft.client.resources.metadata.texture.TextureMetadataSection;
import net.minecraft.resources.Identifier;
import net.minecraft.server.packs.resources.ResourceManager;

public class CubeMapTexture extends ReloadableTexture {
	private static final String[] SUFFIXES = new String[]{"_1.png", "_3.png", "_5.png", "_4.png", "_0.png", "_2.png"};

	public CubeMapTexture(final Identifier resourceId) {
		super(resourceId);
	}

	@Override
	public TextureContents loadContents(final ResourceManager resourceManager) throws IOException {
		Identifier location = this.resourceId();

		try (TextureContents first = TextureContents.load(resourceManager, location.withSuffix(SUFFIXES[0]))) {
			int width = first.image().getWidth();
			int height = first.image().getHeight();
			NativeImage stackedImage = new NativeImage(width, height * 6, false);
			first.image().copyRect(stackedImage, 0, 0, 0, 0, width, height, false, true);

			for (int i = 1; i < 6; i++) {
				try (TextureContents part = TextureContents.load(resourceManager, location.withSuffix(SUFFIXES[i]))) {
					if (part.image().getWidth() != width || part.image().getHeight() != height) {
						throw new IOException(
							"Image dimensions of cubemap '"
								+ location
								+ "' sides do not match: part 0 is "
								+ width
								+ "x"
								+ height
								+ ", but part "
								+ i
								+ " is "
								+ part.image().getWidth()
								+ "x"
								+ part.image().getHeight()
						);
					}

					part.image().copyRect(stackedImage, 0, 0, 0, i * height, width, height, false, true);
				}
			}

			return new TextureContents(stackedImage, new TextureMetadataSection(true, false, MipmapStrategy.MEAN, 0.0F));
		}
	}

	@Override
	protected void doLoad(final NativeImage image) {
		GpuDevice device = RenderSystem.getDevice();
		int width = image.getWidth();
		int height = image.getHeight() / 6;
		this.close();
		this.texture = device.createTexture(this.resourceId()::toString, 21, GpuFormat.RGBA8_UNORM, width, height, 6, 1);
		this.textureView = device.createTextureView(this.texture);
		GpuBufferSlice stagingBuffer = device.createCommandEncoder().transientMemory().uploadStaging(image.getPixelBytes(), 1L, 16);

		for (int i = 0; i < 6; i++) {
			device.createCommandEncoder()
				.copyBufferToTexture(stagingBuffer, 0, height * i, image.getWidth(), image.getHeight(), this.texture, 0, 0, width, height, 0, i);
		}
	}
}