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

A consumer that implements the consumer types of Maybe, Single and Completable
and turns their signals into Notifications for a SingleObserver.
Type parameters:
<T> – the element type of the source
Since:
2.2.4 - experimental/**
 * A consumer that implements the consumer types of Maybe, Single and Completable
 * and turns their signals into Notifications for a SingleObserver.
 * @param <T> the element type of the source
 * @since 2.2.4 - experimental
 */
@Experimental
public final class MaterializeSingleObserver<T>
implements SingleObserver<T>, MaybeObserver<T>, CompletableObserver, Disposable {

    final SingleObserver<? super Notification<T>> downstream;

    Disposable upstream;

    public MaterializeSingleObserver(SingleObserver<? super Notification<T>> downstream) {
        this.downstream = downstream;
    }

    @Override
    public void onSubscribe(Disposable d) {
        if (DisposableHelper.validate(upstream, d)) {
            this.upstream = d;
            downstream.onSubscribe(this);
        }
    }

    @Override
    public void onComplete() {
        downstream.onSuccess(Notification.<T>createOnComplete());
    }

    @Override
    public void onSuccess(T t) {
        downstream.onSuccess(Notification.<T>createOnNext(t));
    }

    @Override
    public void onError(Throwable e) {
        downstream.onSuccess(Notification.<T>createOnError(e));
    }

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

    @Override
    public void dispose() {
        upstream.dispose();
    }
}