package com.google.common.util.concurrent;

import static com.google.common.truth.Truth.assertThat;
import static com.google.common.util.concurrent.Futures.immediateFuture;
import static com.google.common.util.concurrent.Futures.transformAsync;
import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
import static com.google.common.util.concurrent.Uninterruptibles.awaitUninterruptibly;
import static org.junit.Assert.assertThrows;

package com.google.common.util.concurrent;

import static com.google.common.truth.Truth.assertThat;
import static com.google.common.util.concurrent.Futures.immediateFuture;
import static com.google.common.util.concurrent.Futures.transformAsync;
import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
import static com.google.common.util.concurrent.Uninterruptibles.awaitUninterruptibly;
import static org.junit.Assert.assertThrows;

import java.util.concurrent.Future;
import org.jspecify.annotations.Nullable;

/**
 * Transforms a value, possibly asynchronously. For an example usage and more information, see
 * {@link Futures#transformAsync(ListenableFuture, AsyncFunction, Executor)}.
 *
 * @author Chris Povirk
 * @since 11.0
 */
@GwtCompatible
public interface AsyncFunction<I extends @Nullable Object, O extends @Nullable Object> {
  /**

  }

  @SuppressWarnings("FutureTransformAsync") // We intentionally test transformAsync.
  public void testTransformAsync_genericsWildcard_asyncFunction() throws Exception {
    ListenableFuture<?> nullFuture = immediateVoidFuture();
    ListenableFuture<?> chainedFuture =
        transformAsync(nullFuture, x -> immediateFuture("hi"), directExecutor());
    assertThat(getDone(chainedFuture)).isEqualTo("hi");

  }

  @SuppressWarnings("FutureTransformAsync") // We intentionally test transformAsync.
  public void testTransformAsync_genericsWildcard_asyncFunction() throws Exception {
    ListenableFuture<?> nullFuture = immediateVoidFuture();
    ListenableFuture<?> chainedFuture =
        transformAsync(nullFuture, x -> immediateFuture("hi"), directExecutor());
    assertThat(getDone(chainedFuture)).isEqualTo("hi");

        };
    return derive(state.future.transformAsync(applyFunction, executor));
  }

  /**
   * Returns an {@link AsyncClosingFunction} that applies an {@link AsyncFunction} to an input,
   * ignoring the DeferredCloser and returning a {@code ClosingFuture} derived from the returned
   * {@link ListenableFuture}.
   *
   * <p>Use this method to pass a transformation to {@link #transformAsync(AsyncClosingFunction,

    assertClosed(closeable1, closeable2);
  }

  public void testTransformAsync() throws Exception {
    ClosingFuture<String> closingFuture =
        ClosingFuture.from(immediateFuture("value"))
            .transformAsync(
                (DeferredCloser closer, String v) -> {
                  closer.eventuallyClose(closeable1, closingExecutor);
                  closer.eventuallyClose(closeable2, closingExecutor);

    assertClosed(closeable1, closeable2);
  }

  public void testTransformAsync() throws Exception {
    ClosingFuture<String> closingFuture =
        ClosingFuture.from(immediateFuture("value"))
            .transformAsync(
                (DeferredCloser closer, String v) -> {
                  closer.eventuallyClose(closeable1, closingExecutor);
                  closer.eventuallyClose(closeable2, closingExecutor);

    assertThat(f.get()).isEqualTo(2);
  }

  public void testTransformAsync() throws Exception {
    FluentFuture<Integer> f =
        FluentFuture.from(immediateFuture(1))
            .transformAsync(i -> immediateFuture(i + 1), directExecutor());
    assertThat(f.get()).isEqualTo(2);
  }

  @J2ktIncompatible
  @GwtIncompatible // withTimeout
  public void testWithTimeout() throws Exception {

    assertThat(f.get()).isEqualTo(2);
  }

  public void testTransformAsync() throws Exception {
    FluentFuture<Integer> f =
        FluentFuture.from(immediateFuture(1))
            .transformAsync(i -> immediateFuture(i + 1), directExecutor());
    assertThat(f.get()).isEqualTo(2);
  }

  @J2ktIncompatible
  @GwtIncompatible // withTimeout
  public void testWithTimeout() throws Exception {