package org.eclipse.aether.named.hazelcast;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.HashMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import org.eclipse.aether.RepositorySystemSession;
import org.eclipse.aether.SyncContext;
import org.eclipse.aether.artifact.DefaultArtifact;
import org.eclipse.aether.internal.impl.synccontext.named.DiscriminatingNameMapper;
import org.eclipse.aether.internal.impl.synccontext.named.GAVNameMapper;
import org.eclipse.aether.internal.impl.synccontext.named.NamedLockFactoryAdapter;
import org.eclipse.aether.named.NamedLockFactory;
import org.eclipse.aether.repository.LocalRepository;
import org.eclipse.aether.spi.synccontext.SyncContextFactory;
import org.junit.AfterClass;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

/**
 * UT support for {@link SyncContextFactory}.
 */
public abstract class NamedLockFactoryAdapterTestSupport
{
    protected static final HazelcastClientUtils utils = new HazelcastClientUtils();

    private static final long ADAPTER_TIME = 100L;

    private static final TimeUnit ADAPTER_TIME_UNIT = TimeUnit.MILLISECONDS;

    /**
     * Subclass should populate this field, using {@link #setNamedLockFactory(NamedLockFactory)}, but subclass
     * must take care of proper cleanup as well, if needed!
     */
    private static NamedLockFactoryAdapter adapter;

    private RepositorySystemSession session;

    protected static void setNamedLockFactory( final NamedLockFactory namedLockFactory )
    {
        adapter = new NamedLockFactoryAdapter(
                new DiscriminatingNameMapper( new GAVNameMapper() ), namedLockFactory
        );
    }

    @AfterClass
    public static void cleanup()
    {
        if ( adapter != null )
        {
            adapter.shutdown();
        }

        utils.cleanup();
    }

    @Before
    public void before() throws IOException
    {
        Files.createDirectories( Paths.get( System.getProperty( "java.io.tmpdir" ) ) ); // hack for Surefire
        LocalRepository localRepository = new LocalRepository( Files.createTempDirectory( "test" ).toFile() );
        session = mock( RepositorySystemSession.class );
        when( session.getLocalRepository() ).thenReturn( localRepository );
        HashMap<String, Object> config = new HashMap<>();
        config.put( NamedLockFactoryAdapter.TIME_KEY, String.valueOf( ADAPTER_TIME ) );
        config.put( NamedLockFactoryAdapter.TIME_UNIT_KEY, ADAPTER_TIME_UNIT.name() );
        when( session.getConfigProperties() ).thenReturn( config );
    }

    @Test
    public void justCreateAndClose()
    {
        adapter.newInstance( session, false ).close();
    }

    @Test
    public void justAcquire()
    {
        try ( SyncContext syncContext = adapter.newInstance( session, false ) )
        {
            syncContext.acquire(
                    Arrays.asList( new DefaultArtifact( "groupId:artifactId:1.0" ),
                            new DefaultArtifact( "groupId:artifactId:1.1" ) ),
                    null
            );
        }
    }

    @Test( timeout = 5000 )
    public void sharedAccess() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 2 ); // we expect 2 winners
        CountDownLatch losers = new CountDownLatch( 0 ); // we expect 0 losers
        Thread t1 = new Thread( new Access( true, winners, losers, adapter, session, null ) );
        Thread t2 = new Thread( new Access( true, winners, losers, adapter, session, null ) );
        t1.start();
        t2.start();
        t1.join();
        t2.join();
        winners.await();
        losers.await();
    }

    @Test( timeout = 5000 )
    public void exclusiveAccess() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 1 ); // we expect 1 winner
        CountDownLatch losers = new CountDownLatch( 1 ); // we expect 1 loser
        Thread t1 = new Thread( new Access( false, winners, losers, adapter, session, null ) );
        Thread t2 = new Thread( new Access( false, winners, losers, adapter, session, null ) );
        t1.start();
        t2.start();
        t1.join();
        t2.join();
        winners.await();
        losers.await();
    }

    @Test( timeout = 5000 )
    public void mixedAccess() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 1 ); // we expect 1 winner
        CountDownLatch losers = new CountDownLatch( 1 ); // we expect 1 loser
        Thread t1 = new Thread( new Access( true, winners, losers, adapter, session, null ) );
        Thread t2 = new Thread( new Access( false, winners, losers, adapter, session, null ) );
        t1.start();
        t2.start();
        t1.join();
        t2.join();
        winners.await();
        losers.await();
    }

    @Test( timeout = 5000 )
    public void nestedSharedShared() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 2 ); // we expect 2 winners
        CountDownLatch losers = new CountDownLatch( 0 ); // we expect 0 losers
        Thread t1 = new Thread(
                new Access( true, winners, losers, adapter, session,
                        new Access( true, winners, losers, adapter, session, null )
                )
        );
        t1.start();
        t1.join();
        winners.await();
        losers.await();
    }

    @Test( timeout = 5000 )
    public void nestedExclusiveShared() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 2 ); // we expect 2 winners
        CountDownLatch losers = new CountDownLatch( 0 ); // we expect 0 losers
        Thread t1 = new Thread(
                new Access( false, winners, losers, adapter, session,
                        new Access( true, winners, losers, adapter, session, null )
                )
        );
        t1.start();
        t1.join();
        winners.await();
        losers.await();
    }

    @Test( timeout = 5000 )
    public void nestedExclusiveExclusive() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 2 ); // we expect 2 winners
        CountDownLatch losers = new CountDownLatch( 0 ); // we expect 0 losers
        Thread t1 = new Thread(
                new Access( false, winners, losers, adapter, session,
                        new Access( false, winners, losers, adapter, session, null )
                )
        );
        t1.start();
        t1.join();
        winners.await();
        losers.await();
    }

    @Test( timeout = 5000 )
    public void nestedSharedExclusive() throws InterruptedException
    {
        CountDownLatch winners = new CountDownLatch( 1 ); // we expect 1 winner (outer)
        CountDownLatch losers = new CountDownLatch( 1 ); // we expect 1 loser (inner)
        Thread t1 = new Thread(
                new Access( true, winners, losers, adapter, session,
                        new Access( false, winners, losers, adapter, session, null )
                )
        );
        t1.start();
        t1.join();
        winners.await();
        losers.await();
    }

    private static class Access implements Runnable
    {
        final boolean shared;
        final CountDownLatch winner;
        final CountDownLatch loser;
        final NamedLockFactoryAdapter adapter;
        final RepositorySystemSession session;
        final Access chained;

        public Access( boolean shared,
                       CountDownLatch winner,
                       CountDownLatch loser,
                       NamedLockFactoryAdapter adapter,
                       RepositorySystemSession session,
                       Access chained )
        {
            this.shared = shared;
            this.winner = winner;
            this.loser = loser;
            this.adapter = adapter;
            this.session = session;
            this.chained = chained;
        }

        @Override
        public void run()
        {
            try
            {
                try ( SyncContext syncContext = adapter.newInstance( session, shared ) )
                {
                    syncContext.acquire(
                            Arrays.asList( new DefaultArtifact( "groupId:artifactId:1.0" ),
                                    new DefaultArtifact( "groupId:artifactId:1.1" ) ),
                            null
                    );
                    winner.countDown();
                    if ( chained != null )
                    {
                        chained.run();
                    }
                    loser.await();
                }
                catch ( IllegalStateException e )
                {
                    loser.countDown();
                    winner.await();
                }
            }
            catch ( InterruptedException e )
            {
                Assert.fail( "interrupted" );
            }
        }
    }
}