/**

* Copyright 2016 Netflix, Inc.

*

* 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.tck;

import java.util.concurrent.atomic.AtomicInteger;

import org.reactivestreams.*;

import io.reactivex.Flowable;

import io.reactivex.internal.functions.ObjectHelper;

import io.reactivex.internal.subscriptions.SubscriptionHelper;

import io.reactivex.internal.util.*;

/**

* Helper Flowable that makes sure invalid requests from downstream are reported

* as onErrors (instead of RxJavaPlugins.onError). Since requests can be

* async to the onXXX method calls, we need half-serialization to ensure correct

* operations.

*

* @param <T> the value type

*/

public final class FlowableTck<T> extends Flowable<T> {

/**

* Wraps a given Publisher and makes sure invalid requests trigger an onError(IllegalArgumentException).

* @param <T> the value type

* @param source the source to wrap, not null

* @return the new Flowable instance

*/

public static <T> Flowable<T> wrap(Publisher<T> source) {

return new FlowableTck<T>(ObjectHelper.requireNonNull(source, "source is null"));

}

final Publisher<T> source;

FlowableTck(Publisher<T> source) {

this.source = source;

}

@Override

protected void subscribeActual(Subscriber<? super T> s) {

source.subscribe(new TckSubscriber<T>(s));

}

static final class TckSubscriber<T>

extends AtomicInteger

implements Subscriber<T>, Subscription {

private static final long serialVersionUID = -4945028590049415624L;

final Subscriber<? super T> actual;

final AtomicThrowable error;

Subscription s;

TckSubscriber(Subscriber<? super T> actual) {

this.actual = actual;

this.error = new AtomicThrowable();

}

@Override

public void request(long n) {

if (n <= 0) {

s.cancel();

onError(new IllegalArgumentException("§3.9 violated: positive request amount required but it was " + n));

} else {

s.request(n);

}

}

@Override

public void cancel() {

s.cancel();

}

@Override

public void onSubscribe(Subscription s) {

if (SubscriptionHelper.validate(this.s, s)) {

this.s = s;

actual.onSubscribe(this);

}

}

@Override

public void onNext(T t) {

HalfSerializer.onNext(actual, t, this, error);

}

@Override

public void onError(Throwable t) {

HalfSerializer.onError(actual, t, this, error);

}

@Override

public void onComplete() {

HalfSerializer.onComplete(actual, this, error);

}

}

}