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.parallel;

import org.reactivestreams.*;

import io.reactivex.exceptions.*;
import io.reactivex.functions.*;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.internal.fuseable.ConditionalSubscriber;
import io.reactivex.internal.subscriptions.SubscriptionHelper;
import io.reactivex.parallel.*;
import io.reactivex.plugins.RxJavaPlugins;

Calls a Consumer for each upstream value passing by
and handles any failure with a handler function.
History: 2.0.8 - experimental
Type parameters:
<T> – the input value type
Since:
2.2/**
 * Calls a Consumer for each upstream value passing by
 * and handles any failure with a handler function.
 * <p>History: 2.0.8 - experimental
 * @param <T> the input value type
 * @since 2.2
 */
public final class ParallelDoOnNextTry<T> extends ParallelFlowable<T> {

    final ParallelFlowable<T> source;

    final Consumer<? super T> onNext;

    final BiFunction<? super Long, ? super Throwable, ParallelFailureHandling> errorHandler;

    public ParallelDoOnNextTry(ParallelFlowable<T> source, Consumer<? super T> onNext,
            BiFunction<? super Long, ? super Throwable, ParallelFailureHandling> errorHandler) {
        this.source = source;
        this.onNext = onNext;
        this.errorHandler = errorHandler;
    }

    @Override
    public void subscribe(Subscriber<? super T>[] subscribers) {
        if (!validate(subscribers)) {
            return;
        }

        int n = subscribers.length;
        @SuppressWarnings("unchecked")
        Subscriber<? super T>[] parents = new Subscriber[n];

        for (int i = 0; i < n; i++) {
            Subscriber<? super T> a = subscribers[i];
            if (a instanceof ConditionalSubscriber) {
                parents[i] = new ParallelDoOnNextConditionalSubscriber<T>((ConditionalSubscriber<? super T>)a, onNext, errorHandler);
            } else {
                parents[i] = new ParallelDoOnNextSubscriber<T>(a, onNext, errorHandler);
            }
        }

        source.subscribe(parents);
    }

    @Override
    public int parallelism() {
        return source.parallelism();
    }

    static final class ParallelDoOnNextSubscriber<T> implements ConditionalSubscriber<T>, Subscription {

        final Subscriber<? super T> downstream;

        final Consumer<? super T> onNext;

        final BiFunction<? super Long, ? super Throwable, ParallelFailureHandling> errorHandler;

        Subscription upstream;

        boolean done;

        ParallelDoOnNextSubscriber(Subscriber<? super T> actual, Consumer<? super T> onNext,
                BiFunction<? super Long, ? super Throwable, ParallelFailureHandling> errorHandler) {
            this.downstream = actual;
            this.onNext = onNext;
            this.errorHandler = errorHandler;
        }

        @Override
        public void request(long n) {
            upstream.request(n);
        }

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

        @Override
        public void onSubscribe(Subscription s) {
            if (SubscriptionHelper.validate(this.upstream, s)) {
                this.upstream = s;

                downstream.onSubscribe(this);
            }
        }

        @Override
        public void onNext(T t) {
            if (!tryOnNext(t)) {
                upstream.request(1);
            }
        }

        @Override
        public boolean tryOnNext(T t) {
            if (done) {
                return false;
            }
            long retries = 0;

            for (;;) {
                try {
                    onNext.accept(t);
                } catch (Throwable ex) {
                    Exceptions.throwIfFatal(ex);

                    ParallelFailureHandling h;

                    try {
                        h = ObjectHelper.requireNonNull(errorHandler.apply(++retries, ex), "The errorHandler returned a null item");
                    } catch (Throwable exc) {
                        Exceptions.throwIfFatal(exc);
                        cancel();
                        onError(new CompositeException(ex, exc));
                        return false;
                    }

                    switch (h) {
                    case RETRY:
                        continue;
                    case SKIP:
                        return false;
                    case STOP:
                        cancel();
                        onComplete();
                        return false;
                    default:
                        cancel();
                        onError(ex);
                        return false;
                    }
                }

                downstream.onNext(t);
                return true;
            }
        }

        @Override
        public void onError(Throwable t) {
            if (done) {
                RxJavaPlugins.onError(t);
                return;
            }
            done = true;
            downstream.onError(t);
        }

        @Override
        public void onComplete() {
            if (done) {
                return;
            }
            done = true;
            downstream.onComplete();
        }

    }
    static final class ParallelDoOnNextConditionalSubscriber<T> implements ConditionalSubscriber<T>, Subscription {

        final ConditionalSubscriber<? super T> downstream;

        final Consumer<? super T> onNext;

        final BiFunction<? super Long, ? super Throwable, ParallelFailureHandling> errorHandler;

        Subscription upstream;

        boolean done;

        ParallelDoOnNextConditionalSubscriber(ConditionalSubscriber<? super T> actual,
                Consumer<? super T> onNext,
                BiFunction<? super Long, ? super Throwable, ParallelFailureHandling> errorHandler) {
            this.downstream = actual;
            this.onNext = onNext;
            this.errorHandler = errorHandler;
        }

        @Override
        public void request(long n) {
            upstream.request(n);
        }

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

        @Override
        public void onSubscribe(Subscription s) {
            if (SubscriptionHelper.validate(this.upstream, s)) {
                this.upstream = s;

                downstream.onSubscribe(this);
            }
        }

        @Override
        public void onNext(T t) {
            if (!tryOnNext(t) && !done) {
                upstream.request(1);
            }
        }

        @Override
        public boolean tryOnNext(T t) {
            if (done) {
                return false;
            }
            long retries = 0;

            for (;;) {
                try {
                    onNext.accept(t);
                } catch (Throwable ex) {
                    Exceptions.throwIfFatal(ex);

                    ParallelFailureHandling h;

                    try {
                        h = ObjectHelper.requireNonNull(errorHandler.apply(++retries, ex), "The errorHandler returned a null item");
                    } catch (Throwable exc) {
                        Exceptions.throwIfFatal(exc);
                        cancel();
                        onError(new CompositeException(ex, exc));
                        return false;
                    }

                    switch (h) {
                    case RETRY:
                        continue;
                    case SKIP:
                        return false;
                    case STOP:
                        cancel();
                        onComplete();
                        return false;
                    default:
                        cancel();
                        onError(ex);
                        return false;
                    }
                }

                return downstream.tryOnNext(t);
            }
        }

        @Override
        public void onError(Throwable t) {
            if (done) {
                RxJavaPlugins.onError(t);
                return;
            }
            done = true;
            downstream.onError(t);
        }

        @Override
        public void onComplete() {
            if (done) {
                return;
            }
            done = true;
            downstream.onComplete();
        }

    }
}