/*******************************************************************************
 * Copyright (c) 2009, 2014 Ericsson
 *
 * All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License 2.0 which
 * accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *   Francois Chouinard - Initial API and implementation
 *   Alexandre Montplaisir - Port to JUnit4
 *******************************************************************************/

package org.eclipse.tracecompass.tmf.core.tests.component;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import java.io.IOException;
import java.util.Vector;

import org.eclipse.tracecompass.internal.tmf.core.component.TmfProviderManager;
import org.eclipse.tracecompass.tmf.core.component.ITmfEventProvider;
import org.eclipse.tracecompass.tmf.core.event.ITmfEvent;
import org.eclipse.tracecompass.tmf.core.request.ITmfEventRequest.ExecutionType;
import org.eclipse.tracecompass.tmf.core.request.TmfEventRequest;
import org.eclipse.tracecompass.tmf.core.signal.TmfEndSynchSignal;
import org.eclipse.tracecompass.tmf.core.signal.TmfStartSynchSignal;
import org.eclipse.tracecompass.tmf.core.timestamp.ITmfTimestamp;
import org.eclipse.tracecompass.tmf.core.timestamp.TmfTimeRange;
import org.eclipse.tracecompass.tmf.core.timestamp.TmfTimestamp;
import org.eclipse.tracecompass.tmf.tests.stubs.component.TmfEventProviderStub;
import org.eclipse.tracecompass.tmf.tests.stubs.component.TmfSyntheticEventProviderStub;
import org.eclipse.tracecompass.tmf.tests.stubs.event.TmfSyntheticEventStub;
import org.eclipse.tracecompass.tmf.tests.stubs.trace.TmfTraceStub;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

/**
 * Test suite for the TmfEventProvider class.
 */
public class TmfEventProviderTest {

    private TmfEventProviderStub fEventProvider;
    private TmfSyntheticEventProviderStub fSyntheticEventProvider;

    /**
     * Initialization
     *
     * @throws IOException
     *             If we can't find the test trace (they are committed in the
     *             tree, so it shouldn't happen).
     */
    @Before
    public void setUp() throws IOException {
        fEventProvider = new TmfEventProviderStub();
        fSyntheticEventProvider = new TmfSyntheticEventProviderStub();
    }

    /**
     * Clean-up
     */
    @After
    public void tearDown() {
        fEventProvider.dispose();
        fSyntheticEventProvider.dispose();
    }

    // ------------------------------------------------------------------------
    // getProviders (more a sanity check than a test)
    // ------------------------------------------------------------------------

    /**
     * Test getProviders
     */
    @Test
    public void testGetProviders() {
        // There should be 2 TmfEvent providers: a TmfTraceStub and a
        // TmfEventProviderStub
        ITmfEventProvider[] eventProviders = TmfProviderManager.getProviders(ITmfEvent.class);
        assertEquals("getProviders", 2, eventProviders.length);

        eventProviders = TmfProviderManager.getProviders(ITmfEvent.class, TmfTraceStub.class);
        assertEquals("getProviders", 1, eventProviders.length);

        eventProviders = TmfProviderManager.getProviders(ITmfEvent.class, TmfEventProviderStub.class);
        assertEquals("getProviders", 1, eventProviders.length);

        // There should be 1 TmfSyntheticEventStub provider
        eventProviders = TmfProviderManager.getProviders(TmfSyntheticEventStub.class);
        assertEquals("getProviders", 1, eventProviders.length);
    }

    // ------------------------------------------------------------------------
    // getSyntheticEvent
    // ------------------------------------------------------------------------

    /**
     * Test getPlainEvents
     */
    @Test
    public void testGetPlainEvents() {
        final int NB_EVENTS = 1000;
        final Vector<ITmfEvent> requestedEvents = new Vector<>();

        // Get the TmfSyntheticEventStub provider
        ITmfEventProvider[] eventProviders = TmfProviderManager.getProviders(ITmfEvent.class,
                TmfEventProviderStub.class);
        ITmfEventProvider provider = eventProviders[0];

        TmfTimeRange range = new TmfTimeRange(TmfTimestamp.BIG_BANG, TmfTimestamp.BIG_CRUNCH);
        final TmfEventRequest request = new TmfEventRequest(ITmfEvent.class,
                range, 0, NB_EVENTS, ExecutionType.FOREGROUND) {
            @Override
            public void handleData(ITmfEvent event) {
                super.handleData(event);
                requestedEvents.add(event);
            }
        };

        provider.sendRequest(request);
        try {
            request.waitForCompletion();
            assertEquals("nbEvents", NB_EVENTS, requestedEvents.size());
            assertTrue("isCompleted", request.isCompleted());
            assertFalse("isCancelled", request.isCancelled());

            // Make that we have distinct events.
            // Don't go overboard: we are not validating the stub!
            for (int i = 0; i < NB_EVENTS; i++) {
                assertEquals("Distinct events", i + 1, requestedEvents.get(i).getTimestamp().getValue());
            }
        } catch (InterruptedException e) {
            fail();
        }
    }

    /**
     * Test canceling requests.
     */
    @Test
    public void testCancelRequests() {
        final int NB_EVENTS = 1000;
        final int NUMBER_EVENTS_BEFORE_CANCEL_REQ1 = 10;
        final int NUMBER_EVENTS_BEFORE_CANCEL_REQ2 = 800;

        final Vector<ITmfEvent> requestedEventsReq1 = new Vector<>();
        final Vector<ITmfEvent> requestedEventsReq2 = new Vector<>();

        // Get the TmfSyntheticEventStub provider
        ITmfEventProvider[] eventProviders = TmfProviderManager.getProviders(ITmfEvent.class,
                TmfEventProviderStub.class);
        ITmfEventProvider provider = eventProviders[0];

        TmfTimeRange range = new TmfTimeRange(TmfTimestamp.BIG_BANG, TmfTimestamp.BIG_CRUNCH);

        // Create first request
        final TmfEventRequest request1 = new TmfEventRequest(ITmfEvent.class,
                range, 0, NB_EVENTS, ExecutionType.FOREGROUND) {
            @Override
            public void handleData(ITmfEvent event) {
                super.handleData(event);
                requestedEventsReq1.add(event);

                // cancel sub request
                if (getNbRead() == NUMBER_EVENTS_BEFORE_CANCEL_REQ1) {
                    cancel();
                }
            }
        };

        // Synchronize requests
        ((TmfEventProviderStub) provider).startSynch(new TmfStartSynchSignal(0));

        // Additionally, notify provider for up-coming requests
        provider.notifyPendingRequest(true);

        // Call sendRequest, which will create a coalescing request, but it
        // doesn't send request1 yet
        provider.sendRequest(request1);

        // Check if request1 is not running yet.
        assertFalse("isRunning", request1.isRunning());

        // Create second request
        final TmfEventRequest request2 = new TmfEventRequest(ITmfEvent.class,
                range, 0, NB_EVENTS, ExecutionType.FOREGROUND) {
            @Override
            public void handleData(ITmfEvent event) {
                super.handleData(event);
                requestedEventsReq2.add(event);

                // cancel sub request which will cancel also main request
                if (getNbRead() == NUMBER_EVENTS_BEFORE_CANCEL_REQ2) {
                    cancel();
                }
            }
        };

        // Call sendRequest, which will create a coalescing request, but it
        // doesn't send request2 yet
        provider.sendRequest(request2);

        // Check if request1/2 is not running yet.
        assertFalse("isRunning", request1.isRunning());
        assertFalse("isRunning", request2.isRunning());

        // Send end synch signal, however requests won't be sent
        ((TmfEventProviderStub) provider).endSynch(new TmfEndSynchSignal(0));

        // Check if request1/2 is not running yet.
        assertFalse("isRunning", request1.isRunning());
        assertFalse("isRunning", request2.isRunning());

        // Finally, trigger sending of requests
        provider.notifyPendingRequest(false);

        try {

            // Wait until requests start
            request1.waitForStart();
            request2.waitForStart();

//            // Verify that the requests are running
//            assertTrue("isRunning", request1.isRunning());
//            assertTrue("isRunning", request2.isRunning());

            request1.waitForCompletion();

//            // Check if request2 is still running
//            assertTrue("isRunning",  request2.isRunning());

            // Verify result (request1)
            assertEquals("nbEvents", NUMBER_EVENTS_BEFORE_CANCEL_REQ1, requestedEventsReq1.size());
            assertTrue("isCompleted", request1.isCompleted());
            assertTrue("isCancelled", request1.isCancelled());

            request2.waitForCompletion();

            // Verify result (request2)
            assertEquals("nbEvents", NUMBER_EVENTS_BEFORE_CANCEL_REQ2, requestedEventsReq2.size());
            assertTrue("isCompleted", request2.isCompleted());
            assertTrue("isCancelled", request2.isCancelled());

        } catch (InterruptedException e) {
            fail();
        }
    }

    private static void getSyntheticData(final TmfTimeRange range,
            final int nbEvents) throws InterruptedException {

        final Vector<ITmfEvent> requestedEvents = new Vector<>();

        // Get the event provider
        ITmfEventProvider[] eventProviders = TmfProviderManager
                .getProviders(TmfSyntheticEventStub.class);
        ITmfEventProvider provider = eventProviders[0];

        final TmfEventRequest request = new TmfEventRequest(TmfSyntheticEventStub.class, range,
                0, nbEvents, ExecutionType.FOREGROUND) {
            @Override
            public void handleData(ITmfEvent event) {
                super.handleData(event);
                requestedEvents.add(event);
            }
        };
        provider.sendRequest(request);

        request.waitForCompletion();
        if (nbEvents != -1) {
            assertEquals("nbEvents", nbEvents, requestedEvents.size());
        }
        assertTrue("isCompleted", request.isCompleted());
        assertFalse("isCancelled", request.isCancelled());

        // For each base event, the stub will queue 2 identical synthetic events
        // Ensure that the events are queued properly.
        // Don't go overboard: we are not validating the stub!
        for (int i = 0; i < (nbEvents / 2); i++) {
            assertEquals("Distinct events", i + 1, requestedEvents.get(2 * i + 0).getTimestamp().getValue());
            assertEquals("Distinct events", i + 1, requestedEvents.get(2 * i + 1).getTimestamp().getValue());
        }
    }

    /**
     * Test getSyntheticEvents for equal block sizes.
     */
    @Test
    public void testGetSyntheticEvents_EqualBlockSizes() {
        TmfTimeRange range = new TmfTimeRange(TmfTimestamp.BIG_BANG, TmfTimestamp.BIG_CRUNCH);
        try {
            getSyntheticData(range, 1000);
        } catch (InterruptedException e) {
            fail();
        }
    }

    /**
     * Test getSyntheticEvents
     */
    @Test
    public void testGetSyntheticEvents_TimeRange() {
        ITmfTimestamp start = TmfTimestamp.create(1, (byte) -3);
        ITmfTimestamp end = TmfTimestamp.create(1000, (byte) -3);
        TmfTimeRange range = new TmfTimeRange(start, end);
        try {
            getSyntheticData(range, -1);
        } catch (InterruptedException e) {
            fail();
        }
    }

//    public void testGetSyntheticEvents_WeirdTimeRange1() {
//        TmfTimestamp start = TmfTimestamp.BigBang;
//        TmfTimestamp end = TmfTimestamp.Zero; // TmfTimestamp.create(0, (byte) -3,
//                                              // 0);
//        TmfTimeRange range = new TmfTimeRange(start, end);
//        try {
//            getSyntheticData(range, -1, TmfSyntheticEventProviderStub.BLOCK_SIZE);
//        } catch (InterruptedException e) {
//            fail();
//        }
//    }

//    public void testGetSyntheticEvents_WeirdTimeRange2() {
//        TmfTimestamp start = TmfTimestamp.Zero; // TmfTimestamp.create(0, (byte)
//                                                // -3, 0);
//        TmfTimestamp end = TmfTimestamp.BigCrunch;
//        TmfTimeRange range = new TmfTimeRange(start, end);
//        try {
//            getSyntheticData(range, -1, TmfSyntheticEventProviderStub.BLOCK_SIZE);
//        } catch (InterruptedException e) {
//            fail();
//        }
//    }

    /**
     * Test getProviders (more a sanity check than a test)
     */
    @Test
    public void testGetProviders2() {

        // There should be 2 TmfEvent providers: a TmfTraceStub and a
        // TmfEventProviderStub
        ITmfEventProvider[] eventProviders = TmfProviderManager.getProviders(ITmfEvent.class);
        assertEquals("getProviders", 2, eventProviders.length);

        eventProviders = TmfProviderManager.getProviders(ITmfEvent.class, TmfTraceStub.class);
        assertEquals("getProviders", 1, eventProviders.length);

        eventProviders = TmfProviderManager.getProviders(ITmfEvent.class, TmfEventProviderStub.class);
        assertEquals("getProviders", 1, eventProviders.length);

        // There should be 1 TmfSyntheticEventStub provider
        eventProviders = TmfProviderManager.getProviders(TmfSyntheticEventStub.class);
        assertEquals("getProviders", 1, eventProviders.length);
    }

}