/*
 * 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.rxjava4.internal.operators.single;

import static org.junit.Assert.*;

import java.util.Arrays;

import org.junit.Test;

import io.reactivex.rxjava4.core.*;
import io.reactivex.rxjava4.processors.PublishProcessor;
import io.reactivex.rxjava4.subscribers.TestSubscriber;
import io.reactivex.rxjava4.testsupport.TestHelper;

public class SingleConcatTest extends RxJavaTest {
    @Test
    public void concatWith() {
        Single.just(1).concatWith(Single.just(2))
        .test()
        .assertResult(1, 2);
    }

    @Test
    public void concat2() {
        Single.concat(Single.just(1), Single.just(2))
        .test()
        .assertResult(1, 2);
    }

    @Test
    public void concat3() {
        Single.concat(Single.just(1), Single.just(2), Single.just(3))
        .test()
        .assertResult(1, 2, 3);
    }

    @Test
    public void concat4() {
        Single.concat(Single.just(1), Single.just(2), Single.just(3), Single.just(4))
        .test()
        .assertResult(1, 2, 3, 4);
    }

    @SuppressWarnings("unchecked")
    @Test
    public void concatArray() {
        for (int i = 1; i < 100; i++) {
            Single<Integer>[] array = new Single[i];

            Arrays.fill(array, Single.just(1));

            Single.concatArray(array)
            .to(TestHelper.<Integer>testConsumer())
            .assertSubscribed()
            .assertValueCount(i)
            .assertNoErrors()
            .assertComplete();
        }
    }

    @Test
    public void concatArrayEagerTest() {
        PublishProcessor<String> pp1 = PublishProcessor.create();
        PublishProcessor<String> pp2 = PublishProcessor.create();

        TestSubscriber<String> ts = Single.concatArrayEager(pp1.single("1"), pp2.single("2")).test();

        assertTrue(pp1.hasSubscribers());
        assertTrue(pp2.hasSubscribers());

        pp2.onComplete();
        ts.assertEmpty();
        pp1.onComplete();

        ts.assertResult("1", "2");
        ts.assertComplete();
    }

    @Test
    public void concatEagerIterableTest() {
        PublishProcessor<String> pp1 = PublishProcessor.create();
        PublishProcessor<String> pp2 = PublishProcessor.create();

        TestSubscriber<String> ts = Single.concatEager(Arrays.asList(pp1.single("2"), pp2.single("1"))).test();

        assertTrue(pp1.hasSubscribers());
        assertTrue(pp2.hasSubscribers());

        pp2.onComplete();
        ts.assertEmpty();
        pp1.onComplete();

        ts.assertResult("2", "1");
        ts.assertComplete();
    }

    @Test
    public void concatEagerPublisherTest() {
        PublishProcessor<String> pp1 = PublishProcessor.create();
        PublishProcessor<String> pp2 = PublishProcessor.create();

        TestSubscriber<String> ts = Single.concatEager(Flowable.just(pp1.single("1"), pp2.single("2"))).test();

        assertTrue(pp1.hasSubscribers());
        assertTrue(pp2.hasSubscribers());

        pp2.onComplete();
        ts.assertEmpty();
        pp1.onComplete();

        ts.assertResult("1", "2");
        ts.assertComplete();
    }

    @SuppressWarnings("unchecked")
    @Test
    public void concatObservable() {
        for (int i = 1; i < 100; i++) {
            Single<Integer>[] array = new Single[i];

            Arrays.fill(array, Single.just(1));

            Single.concat(Observable.fromArray(array))
            .to(TestHelper.<Integer>testConsumer())
            .assertSubscribed()
            .assertValueCount(i)
            .assertNoErrors()
            .assertComplete();
        }
    }

    @Test
    public void noSubsequentSubscription() {
        final int[] calls = { 0 };

        Single<Integer> source = Single.create(new SingleOnSubscribe<Integer>() {
            @Override
            public void subscribe(SingleEmitter<Integer> s) throws Exception {
                calls[0]++;
                s.onSuccess(1);
            }
        });

        Single.concatArray(source, source).firstElement()
        .test()
        .assertResult(1);

        assertEquals(1, calls[0]);
    }

    @Test
    public void noSubsequentSubscriptionIterable() {
        final int[] calls = { 0 };

        Single<Integer> source = Single.create(new SingleOnSubscribe<Integer>() {
            @Override
            public void subscribe(SingleEmitter<Integer> s) throws Exception {
                calls[0]++;
                s.onSuccess(1);
            }
        });

        Single.concat(Arrays.asList(source, source)).firstElement()
        .test()
        .assertResult(1);

        assertEquals(1, calls[0]);
    }
}
