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 org.reactivestreams.Subscriber;

import io.reactivex.Flowable;
import io.reactivex.annotations.Nullable;
import io.reactivex.exceptions.*;
import io.reactivex.functions.*;
import io.reactivex.internal.fuseable.ConditionalSubscriber;
import io.reactivex.internal.subscribers.*;
import io.reactivex.internal.util.ExceptionHelper;
import io.reactivex.plugins.RxJavaPlugins;

public final class FlowableDoOnEach<T> extends AbstractFlowableWithUpstream<T, T> {
    final Consumer<? super T> onNext;
    final Consumer<? super Throwable> onError;
    final Action onComplete;
    final Action onAfterTerminate;

    public FlowableDoOnEach(Flowable<T> source, Consumer<? super T> onNext,
            Consumer<? super Throwable> onError,
            Action onComplete,
            Action onAfterTerminate) {
        super(source);
        this.onNext = onNext;
        this.onError = onError;
        this.onComplete = onComplete;
        this.onAfterTerminate = onAfterTerminate;
    }

    @Override
    protected void subscribeActual(Subscriber<? super T> s) {
        if (s instanceof ConditionalSubscriber) {
            source.subscribe(new DoOnEachConditionalSubscriber<T>(
                    (ConditionalSubscriber<? super T>)s, onNext, onError, onComplete, onAfterTerminate));
        } else {
            source.subscribe(new DoOnEachSubscriber<T>(
                    s, onNext, onError, onComplete, onAfterTerminate));
        }
    }

    static final class DoOnEachSubscriber<T> extends BasicFuseableSubscriber<T, T> {
        final Consumer<? super T> onNext;
        final Consumer<? super Throwable> onError;
        final Action onComplete;
        final Action onAfterTerminate;

        DoOnEachSubscriber(
                Subscriber<? super T> actual,
                Consumer<? super T> onNext,
                Consumer<? super Throwable> onError,
                Action onComplete,
                Action onAfterTerminate) {
            super(actual);
            this.onNext = onNext;
            this.onError = onError;
            this.onComplete = onComplete;
            this.onAfterTerminate = onAfterTerminate;
        }

        @Override
        public void onNext(T t) {
            if (done) {
                return;
            }

            if (sourceMode != NONE) {
                downstream.onNext(null);
                return;
            }

            try {
                onNext.accept(t);
            } catch (Throwable e) {
                fail(e);
                return;
            }

            downstream.onNext(t);
        }

        @Override
        public void onError(Throwable t) {
            if (done) {
                RxJavaPlugins.onError(t);
                return;
            }
            done = true;
            boolean relay = true;
            try {
                onError.accept(t);
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                downstream.onError(new CompositeException(t, e));
                relay = false;
            }
            if (relay) {
                downstream.onError(t);
            }

            try {
                onAfterTerminate.run();
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                RxJavaPlugins.onError(e);
            }
        }

        @Override
        public void onComplete() {
            if (done) {
                return;
            }
            try {
                onComplete.run();
            } catch (Throwable e) {
                fail(e);
                return;
            }

            done = true;
            downstream.onComplete();

            try {
                onAfterTerminate.run();
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                RxJavaPlugins.onError(e);
            }
        }

        @Override
        public int requestFusion(int mode) {
            return transitiveBoundaryFusion(mode);
        }

        @Nullable
        @Override
        public T poll() throws Exception {
            T v;

            try {
                v = qs.poll();
            } catch (Throwable ex) {
                Exceptions.throwIfFatal(ex);
                try {
                    onError.accept(ex);
                } catch (Throwable exc) {
                    throw new CompositeException(ex, exc);
                }
                throw ExceptionHelper.<Exception>throwIfThrowable(ex);
            }

            if (v != null) {
                try {
                    try {
                        onNext.accept(v);
                    } catch (Throwable ex) {
                        Exceptions.throwIfFatal(ex);
                        try {
                            onError.accept(ex);
                        } catch (Throwable exc) {
                            throw new CompositeException(ex, exc);
                        }
                        throw ExceptionHelper.<Exception>throwIfThrowable(ex);
                    }
                } finally {
                    onAfterTerminate.run();
                }
            } else {
                if (sourceMode == SYNC) {
                    onComplete.run();

                    onAfterTerminate.run();
                }
            }
            return v;
        }
    }

    static final class DoOnEachConditionalSubscriber<T> extends BasicFuseableConditionalSubscriber<T, T> {
        final Consumer<? super T> onNext;
        final Consumer<? super Throwable> onError;
        final Action onComplete;
        final Action onAfterTerminate;

        DoOnEachConditionalSubscriber(
                ConditionalSubscriber<? super T> actual,
                Consumer<? super T> onNext,
                Consumer<? super Throwable> onError,
                Action onComplete,
                Action onAfterTerminate) {
            super(actual);
            this.onNext = onNext;
            this.onError = onError;
            this.onComplete = onComplete;
            this.onAfterTerminate = onAfterTerminate;
        }

        @Override
        public void onNext(T t) {
            if (done) {
                return;
            }

            if (sourceMode != NONE) {
                downstream.onNext(null);
                return;
            }

            try {
                onNext.accept(t);
            } catch (Throwable e) {
                fail(e);
                return;
            }

            downstream.onNext(t);
        }

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

            try {
                onNext.accept(t);
            } catch (Throwable e) {
                fail(e);
                return false;
            }

            return downstream.tryOnNext(t);
        }

        @Override
        public void onError(Throwable t) {
            if (done) {
                RxJavaPlugins.onError(t);
                return;
            }
            done = true;
            boolean relay = true;
            try {
                onError.accept(t);
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                downstream.onError(new CompositeException(t, e));
                relay = false;
            }
            if (relay) {
                downstream.onError(t);
            }

            try {
                onAfterTerminate.run();
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                RxJavaPlugins.onError(e);
            }
        }

        @Override
        public void onComplete() {
            if (done) {
                return;
            }
            try {
                onComplete.run();
            } catch (Throwable e) {
                fail(e);
                return;
            }

            done = true;
            downstream.onComplete();

            try {
                onAfterTerminate.run();
            } catch (Throwable e) {
                Exceptions.throwIfFatal(e);
                RxJavaPlugins.onError(e);
            }
        }

        @Override
        public int requestFusion(int mode) {
            return transitiveBoundaryFusion(mode);
        }

        @Nullable
        @Override
        public T poll() throws Exception {
            T v;

            try {
                v = qs.poll();
            } catch (Throwable ex) {
                Exceptions.throwIfFatal(ex);
                try {
                    onError.accept(ex);
                } catch (Throwable exc) {
                    throw new CompositeException(ex, exc);
                }
                throw ExceptionHelper.<Exception>throwIfThrowable(ex);
            }

            if (v != null) {
                try {
                    try {
                        onNext.accept(v);
                    } catch (Throwable ex) {
                        Exceptions.throwIfFatal(ex);
                        try {
                            onError.accept(ex);
                        } catch (Throwable exc) {
                            throw new CompositeException(ex, exc);
                        }
                        throw ExceptionHelper.<Exception>throwIfThrowable(ex);
                    }
                } finally {
                    onAfterTerminate.run();
                }
            } else {
                if (sourceMode == SYNC) {
                    onComplete.run();

                    onAfterTerminate.run();
                }
            }
            return v;
        }
    }
}