code: /*
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
   * the License for the specific language governing permissions and limitations under the License.
   */
  
  package io.reactivex.rxjava3.internal.operators.maybe;
  
  import java.util.concurrent.TimeUnit;
  import java.util.concurrent.atomic.AtomicReference;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.disposables.Disposable;
  import io.reactivex.rxjava3.internal.disposables.DisposableHelper;
  
  /**
   * Delays all signal types by the given amount and re-emits them on the given scheduler.
   *
   * @param <T> the value type
   */
  public final class MaybeDelay<T> extends AbstractMaybeWithUpstream<T, T> {
  
      final long delay;
  
      final TimeUnit unit;
  
      final Scheduler scheduler;
  
      final boolean delayError;
  
      public MaybeDelay(MaybeSource<T> source, long delay, TimeUnit unit, Scheduler scheduler, boolean delayError) {
          super(source);
          this.delay = delay;
          this.unit = unit;
          this.scheduler = scheduler;
          this.delayError = delayError;
      }
  
      @Override
      protected void subscribeActual(MaybeObserver<? super T> observer) {
          source.subscribe(new DelayMaybeObserver<>(observer, delay, unit, scheduler, delayError));
      }
  
      static final class DelayMaybeObserver<T>
      extends AtomicReference<Disposable>
      implements MaybeObserver<T>, Disposable, Runnable {
  
          private static final long serialVersionUID = 5566860102500855068L;
  
          final MaybeObserver<? super T> downstream;
  
          final long delay;
  
          final TimeUnit unit;
  
          final Scheduler scheduler;
  
          final boolean delayError;
  
          T value;
  
          Throwable error;
  
          DelayMaybeObserver(MaybeObserver<? super T> actual, long delay, TimeUnit unit, Scheduler scheduler, boolean delayError) {
              this.downstream = actual;
              this.delay = delay;
              this.unit = unit;
              this.scheduler = scheduler;
              this.delayError = delayError;
          }
  
          @Override
          public void run() {
              Throwable ex = error;
              if (ex != null) {
                  downstream.onError(ex);
              } else {
                  T v = value;
                  if (v != null) {
                      downstream.onSuccess(v);
                  } else {
                      downstream.onComplete();
                  }
              }
          }
  
          @Override
          public void dispose() {
              DisposableHelper.dispose(this);
          }
  
          @Override
          public boolean isDisposed() {
              return DisposableHelper.isDisposed(get());
          }
  
          @Override
          public void onSubscribe(Disposable d) {
              if (DisposableHelper.setOnce(this, d)) {
                  downstream.onSubscribe(this);
              }
          }
  
          @Override
          public void onSuccess(T value) {
              this.value = value;
              schedule(delay);
          }
  
          @Override
          public void onError(Throwable e) {
              this.error = e;
              schedule(delayError ? delay : 0);
          }
  
          @Override
          public void onComplete() {
              schedule(delay);
          }
  
          void schedule(long delay) {
              DisposableHelper.replace(this, scheduler.scheduleDirect(this, delay, unit));
          }
      }
  }
  