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.
/**
 * 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.internal.operators.mixed;

import java.util.concurrent.atomic.AtomicReference;

import io.reactivex.*;
import io.reactivex.disposables.Disposable;
import io.reactivex.internal.disposables.DisposableHelper;

After Completable completes, it relays the signals
of the ObservableSource to the downstream observer.
Type parameters:
<R> – the result type of the ObservableSource and this operator
Since:
2.1.15/**
 * After Completable completes, it relays the signals
 * of the ObservableSource to the downstream observer.
 * 
 * @param <R> the result type of the ObservableSource and this operator
 * @since 2.1.15
 */
public final class CompletableAndThenObservable<R> extends Observable<R> {

    final CompletableSource source;

    final ObservableSource<? extends R> other;

    public CompletableAndThenObservable(CompletableSource source,
            ObservableSource<? extends R> other) {
        this.source = source;
        this.other = other;
    }

    @Override
    protected void subscribeActual(Observer<? super R> observer) {
        AndThenObservableObserver<R> parent = new AndThenObservableObserver<R>(observer, other);
        observer.onSubscribe(parent);
        source.subscribe(parent);
    }

    static final class AndThenObservableObserver<R>
    extends AtomicReference<Disposable>
    implements Observer<R>, CompletableObserver, Disposable {

        private static final long serialVersionUID = -8948264376121066672L;

        final Observer<? super R> downstream;

        ObservableSource<? extends R> other;

        AndThenObservableObserver(Observer<? super R> downstream, ObservableSource<? extends R> other) {
            this.other = other;
            this.downstream = downstream;
        }

        @Override
        public void onNext(R t) {
            downstream.onNext(t);
        }

        @Override
        public void onError(Throwable t) {
            downstream.onError(t);
        }

        @Override
        public void onComplete() {
            ObservableSource<? extends R> o = other;
            if (o == null) {
                downstream.onComplete();
            } else {
                other = null;
                o.subscribe(this);
            }
        }

        @Override
        public void dispose() {
            DisposableHelper.dispose(this);
        }

        @Override
        public boolean isDisposed() {
            return DisposableHelper.isDisposed(get());
        }

        @Override
        public void onSubscribe(Disposable d) {
            DisposableHelper.replace(this, d);
        }

    }
}