package net.minecraft.client.resources;

import com.mojang.blaze3d.platform.NativeImage;
import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
import java.util.Objects;
import net.minecraft.client.renderer.texture.DynamicTexture;
import net.minecraft.client.renderer.texture.TextureManager;
import net.minecraft.resources.Identifier;
import net.minecraft.world.level.material.MapColor;
import net.minecraft.world.level.saveddata.maps.MapId;
import net.minecraft.world.level.saveddata.maps.MapItemSavedData;

public class MapTextureManager implements AutoCloseable {
	private final Int2ObjectMap<MapTextureManager.MapInstance> maps = new Int2ObjectOpenHashMap<>();
	private final TextureManager textureManager;

	public MapTextureManager(final TextureManager textureManager) {
		this.textureManager = textureManager;
	}

	public void update(final MapId id, final MapItemSavedData data) {
		this.getOrCreateMapInstance(id, data).forceUpload();
	}

	public Identifier prepareMapTexture(final MapId id, final MapItemSavedData data) {
		MapTextureManager.MapInstance mapInstance = this.getOrCreateMapInstance(id, data);
		mapInstance.updateTextureIfNeeded();
		return mapInstance.location;
	}

	public void resetData() {
		for (MapTextureManager.MapInstance mapInstance : this.maps.values()) {
			mapInstance.close();
		}

		this.maps.clear();
	}

	private MapTextureManager.MapInstance getOrCreateMapInstance(final MapId id, final MapItemSavedData data) {
		return this.maps.compute(id.id(), (k, instance) -> {
			if (instance == null) {
				return new MapTextureManager.MapInstance(k, data);
			} else {
				instance.replaceMapData(data);
				return instance;
			}
		});
	}

	public void close() {
		this.resetData();
	}

	private class MapInstance implements AutoCloseable {
		private MapItemSavedData data;
		private final DynamicTexture texture;
		private boolean requiresUpload;
		private final Identifier location;

		private MapInstance(final int id, final MapItemSavedData data) {
			Objects.requireNonNull(MapTextureManager.this);
			super();
			this.requiresUpload = true;
			this.data = data;
			this.texture = new DynamicTexture(() -> "Map " + id, 128, 128, true);
			this.location = Identifier.withDefaultNamespace("map/" + id);
			MapTextureManager.this.textureManager.register(this.location, this.texture);
		}

		private void replaceMapData(final MapItemSavedData data) {
			boolean dataChanged = this.data != data;
			this.data = data;
			this.requiresUpload |= dataChanged;
		}

		public void forceUpload() {
			this.requiresUpload = true;
		}

		private void updateTextureIfNeeded() {
			if (this.requiresUpload) {
				NativeImage pixels = this.texture.getPixels();

				for (int y = 0; y < 128; y++) {
					for (int x = 0; x < 128; x++) {
						int i = x + y * 128;
						pixels.setPixel(x, y, MapColor.getColorFromPackedId(this.data.colors[i]));
					}
				}

				this.texture.upload();
				this.requiresUpload = false;
			}
		}

		public void close() {
			this.texture.close();
		}
	}
}