/**
 * 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.observers;

import static org.junit.Assert.*;
import static org.mockito.Mockito.*;

import java.io.IOException;
import java.util.*;
import java.util.concurrent.*;

import org.junit.*;
import org.junit.rules.ExpectedException;
import org.mockito.InOrder;
import org.reactivestreams.Subscriber;

import io.reactivex.*;
import io.reactivex.disposables.*;
import io.reactivex.exceptions.TestException;
import io.reactivex.functions.Consumer;
import io.reactivex.internal.fuseable.QueueDisposable;
import io.reactivex.internal.operators.observable.ObservableScalarXMap.ScalarDisposable;
import io.reactivex.internal.subscriptions.EmptySubscription;
import io.reactivex.processors.PublishProcessor;
import io.reactivex.schedulers.Schedulers;
import io.reactivex.subscribers.TestSubscriber;

public class TestObserverTest {

    @Rule
    public ExpectedException thrown = ExpectedException.none();

    @Test
    public void testAssert() {
        Flowable<Integer> oi = Flowable.fromIterable(Arrays.asList(1, 2));
        TestSubscriber<Integer> o = new TestSubscriber<Integer>();
        oi.subscribe(o);

        o.assertValues(1, 2);
        o.assertValueCount(2);
        o.assertTerminated();
    }

    @Test
    public void testAssertNotMatchCount() {
        Flowable<Integer> oi = Flowable.fromIterable(Arrays.asList(1, 2));
        TestSubscriber<Integer> o = new TestSubscriber<Integer>();
        oi.subscribe(o);

        thrown.expect(AssertionError.class);
        // FIXME different message format
//        thrown.expectMessage("Number of items does not match. Provided: 1  Actual: 2");

        o.assertValue(1);
        o.assertValueCount(2);
        o.assertTerminated();
    }

    @Test
    public void testAssertNotMatchValue() {
        Flowable<Integer> oi = Flowable.fromIterable(Arrays.asList(1, 2));
        TestSubscriber<Integer> o = new TestSubscriber<Integer>();
        oi.subscribe(o);

        thrown.expect(AssertionError.class);
        // FIXME different message format
//        thrown.expectMessage("Value at index: 1 expected to be [3] (Integer) but was: [2] (Integer)");

        o.assertValues(1, 3);
        o.assertValueCount(2);
        o.assertTerminated();
    }

    @Test
    public void testAssertTerminalEventNotReceived() {
        PublishProcessor<Integer> p = PublishProcessor.create();
        TestSubscriber<Integer> o = new TestSubscriber<Integer>();
        p.subscribe(o);

        p.onNext(1);
        p.onNext(2);

        thrown.expect(AssertionError.class);
        // FIXME different message format
//        thrown.expectMessage("No terminal events received.");

        o.assertValues(1, 2);
        o.assertValueCount(2);
        o.assertTerminated();
    }

    @Test
    public void testWrappingMock() {
        Flowable<Integer> oi = Flowable.fromIterable(Arrays.asList(1, 2));

        Subscriber<Integer> mockObserver = TestHelper.mockSubscriber();
        
        oi.subscribe(new TestSubscriber<Integer>(mockObserver));

        InOrder inOrder = inOrder(mockObserver);
        inOrder.verify(mockObserver, times(1)).onNext(1);
        inOrder.verify(mockObserver, times(1)).onNext(2);
        inOrder.verify(mockObserver, times(1)).onComplete();
        inOrder.verifyNoMoreInteractions();
    }

    @Test
    public void testWrappingMockWhenUnsubscribeInvolved() {
        Flowable<Integer> oi = Flowable.fromIterable(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9)).take(2);
        Subscriber<Integer> mockObserver = TestHelper.mockSubscriber();
        oi.subscribe(new TestSubscriber<Integer>(mockObserver));

        InOrder inOrder = inOrder(mockObserver);
        inOrder.verify(mockObserver, times(1)).onNext(1);
        inOrder.verify(mockObserver, times(1)).onNext(2);
        inOrder.verify(mockObserver, times(1)).onComplete();
        inOrder.verifyNoMoreInteractions();
    }
    
    @Test
    public void testErrorSwallowed() {
        Flowable.error(new RuntimeException()).subscribe(new TestSubscriber<Object>());
    }
    
    @Test
    public void testGetEvents() {
        TestSubscriber<Integer> to = new TestSubscriber<Integer>();
        to.onSubscribe(EmptySubscription.INSTANCE);
        to.onNext(1);
        to.onNext(2);
        
        assertEquals(Arrays.<Object>asList(Arrays.asList(1, 2), 
                Collections.emptyList(), 
                Collections.emptyList()), to.getEvents());
        
        to.onComplete();
        
        assertEquals(Arrays.<Object>asList(Arrays.asList(1, 2), Collections.emptyList(),
                Collections.singletonList(Notification.createOnComplete())), to.getEvents());
        
        TestException ex = new TestException();
        TestSubscriber<Integer> to2 = new TestSubscriber<Integer>();
        to2.onSubscribe(EmptySubscription.INSTANCE);
        to2.onNext(1);
        to2.onNext(2);
        
        assertEquals(Arrays.<Object>asList(Arrays.asList(1, 2), 
                Collections.emptyList(), 
                Collections.emptyList()), to2.getEvents());
        
        to2.onError(ex);
        
        assertEquals(Arrays.<Object>asList(
                Arrays.asList(1, 2),
                Collections.singletonList(ex),
                Collections.emptyList()), 
                    to2.getEvents());
    }

    @Test
    public void testNullExpected() {
        TestSubscriber<Integer> to = new TestSubscriber<Integer>();
        to.onNext(1);

        try {
            to.assertValue(null);
        } catch (AssertionError ex) {
            // this is expected
            return;
        }
        fail("Null element check assertion didn't happen!");
    }
    
    @Test
    public void testNullActual() {
        TestSubscriber<Integer> to = new TestSubscriber<Integer>();
        to.onNext(null);

        try {
            to.assertValue(1);
        } catch (AssertionError ex) {
            // this is expected
            return;
        }
        fail("Null element check assertion didn't happen!");
    }
    
    @Test
    public void testTerminalErrorOnce() {
        TestSubscriber<Integer> to = new TestSubscriber<Integer>();
        to.onError(new TestException());
        to.onError(new TestException());
        
        try {
            to.assertTerminated();
        } catch (AssertionError ex) {
            // this is expected
            return;
        }
        fail("Failed to report multiple onError terminal events!");
    }
    @Test
    public void testTerminalCompletedOnce() {
        TestSubscriber<Integer> to = new TestSubscriber<Integer>();
        to.onComplete();
        to.onComplete();
        
        try {
            to.assertTerminated();
        } catch (AssertionError ex) {
            // this is expected
            return;
        }
        fail("Failed to report multiple onComplete terminal events!");
    }
    
    @Test
    public void testTerminalOneKind() {
        TestSubscriber<Integer> to = new TestSubscriber<Integer>();
        to.onError(new TestException());
        to.onComplete();
        
        try {
            to.assertTerminated();
        } catch (AssertionError ex) {
            // this is expected
            return;
        }
        fail("Failed to report multiple kinds of events!");
    }
    
    @Test
    public void createDelegate() {
        TestObserver<Integer> ts1 = TestObserver.create();
        
        TestObserver<Integer> ts = TestObserver.create(ts1);
        
        ts.assertNotSubscribed();

        assertFalse(ts.hasSubscription());

        ts.onSubscribe(Disposables.empty());
        
        try {
            ts.assertNotSubscribed();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }

        assertTrue(ts.hasSubscription());
        
        assertFalse(ts.isDisposed());
        
        ts.onNext(1);
        ts.onError(new TestException());
        ts.onComplete();
        
        ts1.assertValue(1).assertError(TestException.class).assertComplete();
        
        ts.dispose();
        
        assertTrue(ts.isDisposed());
        
        assertTrue(ts.isTerminated());
        
        assertSame(Thread.currentThread(), ts.lastThread());

        try {
            ts.assertNoValues();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }

        try {
            ts.assertValueCount(0);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }
        
        ts.assertValueSequence(Arrays.asList(1));
        
        try {
            ts.assertValueSequence(Arrays.asList(2));
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }

        ts.assertValueSet(Collections.singleton(1));

        try {
            ts.assertValueSet(Collections.singleton(2));
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }

    }
    
    @Test
    public void assertError() {
        TestObserver<Integer> ts = TestObserver.create();
        
        try {
            ts.assertError(TestException.class);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }

        try {
            ts.assertError(new TestException());
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }

        try {
            ts.assertErrorMessage("");
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            
        }

        try {
            ts.assertSubscribed();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            
        }

        try {
            ts.assertTerminated();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            
        }

        ts.onSubscribe(Disposables.empty());

        ts.assertSubscribed();
        
        ts.assertNoErrors();

        TestException ex = new TestException("Forced failure");
        
        ts.onError(ex);

        ts.assertError(ex);
        
        ts.assertError(TestException.class);

        ts.assertErrorMessage("Forced failure");
        
        try {
            ts.assertErrorMessage("");
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            
        }
        
        try {
            ts.assertError(new RuntimeException());
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }

        try {
            ts.assertError(IOException.class);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }

        try {
            ts.assertNoErrors();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError exc) {
            // expected
        }
        
        ts.assertTerminated();
        
        ts.assertValueCount(0);
        
        ts.assertNoValues();
        
        
    }
    
    @Test
    public void emptyObserverEnum() {
        assertEquals(1, TestObserver.EmptyObserver.values().length);
        assertNotNull(TestObserver.EmptyObserver.valueOf("INSTANCE"));
    }
    
    @Test
    public void valueAndClass() {
        assertEquals("null", TestObserver.valueAndClass(null));
        assertEquals("1 (class: Integer)", TestObserver.valueAndClass(1));
    }
    
    @Test
    public void assertFailure() {
        TestObserver<Integer> ts = TestObserver.create();
        
        ts.onSubscribe(Disposables.empty());
        
        ts.onError(new TestException("Forced failure"));

        ts.assertFailure(TestException.class);
        
        ts.assertFailureAndMessage(TestException.class, "Forced failure");
        
        ts.onNext(1);

        ts.assertFailure(TestException.class, 1);
        
        ts.assertFailureAndMessage(TestException.class, "Forced failure", 1);
    }
    
    @Test
    public void assertFuseable() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());
        
        ts.assertNotFuseable();
        
        try {
            ts.assertFuseable();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
        ts = TestObserver.create();
        ts.setInitialFusionMode(QueueDisposable.ANY);
        
        ts.onSubscribe(new ScalarDisposable<Integer>(ts, 1));
        
        ts.assertFuseable();
        
        ts.assertFusionMode(QueueDisposable.SYNC);
        
        try {
            ts.assertFusionMode(QueueDisposable.NONE);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
        try {
            ts.assertNotFuseable();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
    }
    
    @Test
    public void assertTerminated() {
        TestObserver<Integer> ts = TestObserver.create();
        
        ts.assertNotTerminated();
        
        ts.onError(null);
        
        try {
            ts.assertNotTerminated();
            throw new RuntimeException("Should have thrown!");
        } catch (AssertionError ex) {
            // expected
        }
    }
    
    @Test
    public void assertOf() {
        TestObserver<Integer> ts = TestObserver.create();
       
        ts.assertOf(new Consumer<TestObserver<Integer>>() {
            @Override
            public void accept(TestObserver<Integer> f) throws Exception {
                f.assertNotSubscribed();
            }
        });
        
        try {
            ts.assertOf(new Consumer<TestObserver<Integer>>() {
                @Override
                public void accept(TestObserver<Integer> f) throws Exception {
                    f.assertSubscribed();
                }
            });
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
        try {
            ts.assertOf(new Consumer<TestObserver<Integer>>() {
                @Override
                public void accept(TestObserver<Integer> f) throws Exception {
                    throw new IllegalArgumentException();
                }
            });
            throw new RuntimeException("Should have thrown");
        } catch (IllegalArgumentException ex) {
            // expected
        }
    }
    
    @Test
    public void assertResult() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());
        
        ts.onComplete();
        
        ts.assertResult();
        
        try {
            ts.assertResult(1);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
        ts.onNext(1);
        
        ts.assertResult(1);
        
        try {
            ts.assertResult(2);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
        try {
            ts.assertResult();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }

    }
    
    @Test(timeout = 5000)
    public void await() throws Exception {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());

        assertFalse(ts.await(100, TimeUnit.MILLISECONDS));
        
        ts.awaitDone(100, TimeUnit.MILLISECONDS);
        
        assertTrue(ts.isDisposed());

        assertFalse(ts.awaitTerminalEvent(100, TimeUnit.MILLISECONDS));
        
        assertEquals(0, ts.completions());
        assertEquals(0, ts.errorCount());

        ts.onComplete();
        
        assertTrue(ts.await(100, TimeUnit.MILLISECONDS));
        
        ts.await();
        
        ts.awaitDone(5, TimeUnit.SECONDS);
        
        assertEquals(1, ts.completions());
        assertEquals(0, ts.errorCount());
        
        assertTrue(ts.awaitTerminalEvent());
        
        final TestObserver<Integer> ts1 = TestObserver.create();

        ts1.onSubscribe(Disposables.empty());

        Schedulers.single().scheduleDirect(new Runnable() {
            @Override
            public void run() {
                ts1.onComplete();
            }
        }, 200, TimeUnit.MILLISECONDS);
        
        ts1.await();
        
        ts1.assertValueSet(Collections.<Integer>emptySet());
    }
    
    @Test
    public void errors() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());

        assertEquals(0, ts.errors().size());
        
        ts.onError(new TestException());

        assertEquals(1, ts.errors().size());
        
        TestHelper.assertError(ts.errors(), 0, TestException.class);
    }
    
    @SuppressWarnings("unchecked")
    @Test
    public void onNext() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());

        assertEquals(0, ts.valueCount());
        
        assertEquals(Arrays.asList(), ts.values());
        
        ts.onNext(1);
        
        assertEquals(Arrays.asList(1), ts.values());
        
        ts.cancel();
        
        assertTrue(ts.isCancelled());
        assertTrue(ts.isDisposed());
        
        ts.assertValue(1);
        
        assertEquals(Arrays.asList(Arrays.asList(1), Collections.emptyList(), Collections.emptyList()), ts.getEvents());
    }
    
    @Test
    public void fusionModeToString() {
        assertEquals("NONE", TestObserver.fusionModeToString(QueueDisposable.NONE));
        assertEquals("SYNC", TestObserver.fusionModeToString(QueueDisposable.SYNC));
        assertEquals("ASYNC", TestObserver.fusionModeToString(QueueDisposable.ASYNC));
        assertEquals("Unknown(100)", TestObserver.fusionModeToString(100));
    }
    
    @Test
    public void multipleTerminals() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());

        ts.assertNotComplete();

        ts.onComplete();

        try {
            ts.assertNotComplete();
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }

        ts.assertTerminated();
        
        ts.onComplete();
        
        try {
            ts.assertComplete();
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }

        try {
            ts.assertTerminated();
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }

        try {
            ts.assertNotComplete();
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }
    }
    
    @Test
    public void assertValue() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());

        try {
            ts.assertValue(1);
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }
        
        ts.onNext(1);
        
        ts.assertValue(1);
        
        try {
            ts.assertValue(2);
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }

        ts.onNext(2);
        
        try {
            ts.assertValue(1);
            throw new RuntimeException("Should have thrown");
        } catch (Throwable ex) {
            // expected
        }
    }

    @Test
    public void onNextMisbehave() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onNext(1);
        
        ts.assertError(IllegalStateException.class);
        
        ts = TestObserver.create();
        
        ts.onSubscribe(Disposables.empty());
        
        ts.onNext(null);
        
        ts.assertFailure(NullPointerException.class, (Integer)null);
    }
    
    @Test
    public void awaitTerminalEventInterrupt() {
        final TestObserver<Integer> ts = TestObserver.create();
        
        ts.onSubscribe(Disposables.empty());

        Thread.currentThread().interrupt();
        
        ts.awaitTerminalEvent();

        assertTrue(Thread.interrupted());
        
        Thread.currentThread().interrupt();

        ts.awaitTerminalEvent(5, TimeUnit.SECONDS);

        assertTrue(Thread.interrupted());
    }
    
    @Test
    public void assertTerminated2() {
        TestObserver<Integer> ts = TestObserver.create();
        
        ts.onSubscribe(Disposables.empty());

        assertFalse(ts.isTerminated());
        
        ts.onError(new TestException());
        ts.onError(new IOException());
        
        assertTrue(ts.isTerminated());
        
        try {
            ts.assertTerminated();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        
        try {
            ts.assertError(TestException.class);
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
        

        ts = TestObserver.create();
        
        ts.onSubscribe(Disposables.empty());

        ts.onError(new TestException());
        ts.onComplete();

        try {
            ts.assertTerminated();
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
    }
    
    @Test
    public void onSubscribe() {
        TestObserver<Integer> ts = TestObserver.create();
        
        ts.onSubscribe(null);
        
        ts.assertError(NullPointerException.class);

        ts = TestObserver.create();
        
        ts.onSubscribe(Disposables.empty());
        
        Disposable d1 = Disposables.empty();
        
        ts.onSubscribe(d1);
        
        assertTrue(d1.isDisposed());
        
        ts.assertError(IllegalStateException.class);

        ts = TestObserver.create();
        ts.dispose();
        
        d1 = Disposables.empty();
        
        ts.onSubscribe(d1);
        
        assertTrue(d1.isDisposed());
        
    }

    @Test
    public void assertValueSequence() {
        TestObserver<Integer> ts = TestObserver.create();

        ts.onSubscribe(Disposables.empty());
        
        ts.onNext(1);
        ts.onNext(2);
        
        try {
            ts.assertValueSequence(Arrays.<Integer>asList());
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }

        try {
            ts.assertValueSequence(Arrays.asList(1));
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }

        ts.assertValueSequence(Arrays.asList(1, 2));

        try {
            ts.assertValueSequence(Arrays.asList(1, 2, 3));
            throw new RuntimeException("Should have thrown");
        } catch (AssertionError ex) {
            // expected
        }
    }
}