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.flowable;

import java.util.concurrent.Callable;

import org.reactivestreams.Subscriber;

import io.reactivex.Flowable;
import io.reactivex.exceptions.*;
import io.reactivex.functions.Function;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.internal.subscribers.SinglePostCompleteSubscriber;

public final class FlowableMapNotification<T, R> extends AbstractFlowableWithUpstream<T, R> {

    final Function<? super T, ? extends R> onNextMapper;
    final Function<? super Throwable, ? extends R> onErrorMapper;
    final Callable<? extends R> onCompleteSupplier;

    public FlowableMapNotification(
            Flowable<T> source,
            Function<? super T, ? extends R> onNextMapper,
            Function<? super Throwable, ? extends R> onErrorMapper,
            Callable<? extends R> onCompleteSupplier) {
        super(source);
        this.onNextMapper = onNextMapper;
        this.onErrorMapper = onErrorMapper;
        this.onCompleteSupplier = onCompleteSupplier;
    }

    @Override
    protected void subscribeActual(Subscriber<? super R> s) {
        source.subscribe(new MapNotificationSubscriber<T, R>(s, onNextMapper, onErrorMapper, onCompleteSupplier));
    }

    static final class MapNotificationSubscriber<T, R>
    extends SinglePostCompleteSubscriber<T, R> {

        private static final long serialVersionUID = 2757120512858778108L;
        final Function<? super T, ? extends R> onNextMapper;
        final Function<? super Throwable, ? extends R> onErrorMapper;
        final Callable<? extends R> onCompleteSupplier;

        MapNotificationSubscriber(Subscriber<? super R> actual,
                Function<? super T, ? extends R> onNextMapper,
                Function<? super Throwable, ? extends R> onErrorMapper,
                Callable<? extends R> onCompleteSupplier) {
            super(actual);
            this.onNextMapper = onNextMapper;
            this.onErrorMapper = onErrorMapper;
            this.onCompleteSupplier = onCompleteSupplier;
        }

        @Override
        public void onNext(T t) {
            R p;

            try {
                p = ObjectHelper.requireNonNull(onNextMapper.apply(t), "The onNext publisher returned is null");
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                downstream.onError(e);
                return;
            }

            produced++;
            downstream.onNext(p);
        }

        @Override
        public void onError(Throwable t) {
            R p;

            try {
                p = ObjectHelper.requireNonNull(onErrorMapper.apply(t), "The onError publisher returned is null");
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                downstream.onError(new CompositeException(t, e));
                return;
            }

            complete(p);
        }

        @Override
        public void onComplete() {
            R p;

            try {
                p = ObjectHelper.requireNonNull(onCompleteSupplier.call(), "The onComplete publisher returned is null");
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                downstream.onError(e);
                return;
            }

            complete(p);
        }
    }
}