package net.minecraft.util;

import com.mojang.logging.LogUtils;
import java.util.concurrent.CancellationException;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionException;
import java.util.concurrent.Executor;
import java.util.function.Consumer;
import org.slf4j.Logger;

public class FutureChain implements TaskChainer, AutoCloseable {
	private static final Logger LOGGER = LogUtils.getLogger();
	private CompletableFuture<?> head = CompletableFuture.completedFuture(null);
	private final Executor executor;
	private volatile boolean closed;

	public FutureChain(Executor executor) {
		this.executor = executor;
	}

	@Override
	public <T> void append(CompletableFuture<T> completableFuture, Consumer<T> consumer) {
		this.head = this.head.thenCombine(completableFuture, (object, object2) -> object2).thenAcceptAsync(object -> {
			if (!this.closed) {
				consumer.accept(object);
			}
		}, this.executor).exceptionally(throwable -> {
			if (throwable instanceof CompletionException completionException) {
				throwable = completionException.getCause();
			}

			if (throwable instanceof CancellationException cancellationException) {
				throw cancellationException;
			} else {
				LOGGER.error("Chain link failed, continuing to next one", throwable);
				return null;
			}
		});
	}

	public void close() {
		this.closed = true;
	}
}