package org.infinispan.statetransfer;

import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.any;
import static org.mockito.Matchers.anyInt;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;
import static org.testng.Assert.assertEquals;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentSkipListSet;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

import org.infinispan.Cache;
import org.infinispan.commands.CommandsFactory;
import org.infinispan.commons.hash.MurmurHash3;
import org.infinispan.commons.util.CollectionFactory;
import org.infinispan.commons.util.SmallIntSet;
import org.infinispan.configuration.cache.CacheMode;
import org.infinispan.configuration.cache.Configuration;
import org.infinispan.configuration.cache.ConfigurationBuilder;
import org.infinispan.configuration.cache.VersioningScheme;
import org.infinispan.configuration.global.GlobalConfiguration;
import org.infinispan.configuration.global.GlobalConfigurationBuilder;
import org.infinispan.conflict.impl.InternalConflictManager;
import org.infinispan.container.DataContainer;
import org.infinispan.container.entries.ImmortalCacheEntry;
import org.infinispan.container.entries.InternalCacheEntry;
import org.infinispan.context.InvocationContextFactory;
import org.infinispan.distribution.TestAddress;
import org.infinispan.distribution.TriangleOrderManager;
import org.infinispan.distribution.ch.impl.DefaultConsistentHash;
import org.infinispan.distribution.ch.impl.DefaultConsistentHashFactory;
import org.infinispan.distribution.ch.impl.HashFunctionPartitioner;
import org.infinispan.interceptors.AsyncInterceptorChain;
import org.infinispan.notifications.cachelistener.CacheNotifier;
import org.infinispan.persistence.manager.PersistenceManager;
import org.infinispan.remoting.inboundhandler.DeliverOrder;
import org.infinispan.remoting.responses.Response;
import org.infinispan.remoting.responses.SuccessfulResponse;
import org.infinispan.remoting.rpc.ResponseMode;
import org.infinispan.remoting.rpc.RpcManager;
import org.infinispan.remoting.rpc.RpcOptions;
import org.infinispan.remoting.rpc.RpcOptionsBuilder;
import org.infinispan.remoting.transport.Address;
import org.infinispan.remoting.transport.Transport;
import org.infinispan.test.AbstractInfinispanTest;
import org.infinispan.topology.CacheTopology;
import org.infinispan.topology.LocalTopologyManager;
import org.infinispan.topology.PersistentUUID;
import org.infinispan.topology.PersistentUUIDManager;
import org.infinispan.topology.PersistentUUIDManagerImpl;
import org.infinispan.transaction.impl.LocalTransaction;
import org.infinispan.transaction.impl.RemoteTransaction;
import org.infinispan.transaction.impl.TransactionTable;
import org.infinispan.transaction.totalorder.TotalOrderManager;
import org.infinispan.util.ByteString;
import org.infinispan.util.concurrent.BlockingTaskAwareExecutorService;
import org.infinispan.util.concurrent.CommandAckCollector;
import org.infinispan.util.concurrent.IsolationLevel;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.Test;

/**
 * Tests StateConsumerImpl.
 *
 * @author anistor@redhat.com
 * @since 5.2
 */
@Test(groups = "functional", testName = "statetransfer.StateConsumerTest")
public class StateConsumerTest extends AbstractInfinispanTest {

   private static final Log log = LogFactory.getLog(StateConsumerTest.class);

   private ExecutorService pooledExecutorService;

   @AfterMethod
   public void tearDown() {
      if (pooledExecutorService != null) {
         pooledExecutorService.shutdownNow();
      }
   }

   public void test1() throws Exception {
      // create cache configuration
      ConfigurationBuilder cb = new ConfigurationBuilder();
      cb.clustering().invocationBatching().enable()
            .clustering().cacheMode(CacheMode.DIST_SYNC)
            .clustering().stateTransfer().timeout(10000)
            .versioning().enable().scheme(VersioningScheme.SIMPLE)
            .locking().lockAcquisitionTimeout(200).writeSkewCheck(true).isolationLevel(IsolationLevel.REPEATABLE_READ);

      GlobalConfigurationBuilder gcb = GlobalConfigurationBuilder.defaultClusteredBuilder();
      GlobalConfiguration globalConfiguration = gcb.build();
      Configuration configuration = cb.build();
      PersistentUUIDManager persistentUUIDManager = new PersistentUUIDManagerImpl();

      // create list of 6 members
      Address[] addresses = new Address[4];
      for (int i = 0; i < 4; i++) {
         addresses[i] = new TestAddress(i);
         persistentUUIDManager.addPersistentAddressMapping(addresses[i], PersistentUUID.randomUUID());
      }
      List<Address> members1 = Arrays.asList(addresses[0], addresses[1], addresses[2], addresses[3]);
      List<Address> members2 = Arrays.asList(addresses[0], addresses[1], addresses[2]);

      // create CHes
      DefaultConsistentHashFactory chf = new DefaultConsistentHashFactory();
      DefaultConsistentHash ch1 = chf.create(MurmurHash3.getInstance(), 2, 40, members1, null);
      final DefaultConsistentHash ch2 = chf.updateMembers(ch1, members2, null);
      DefaultConsistentHash ch3 = chf.rebalance(ch2);
      DefaultConsistentHash ch23 = chf.union(ch2, ch3);

      log.debug(ch1);
      log.debug(ch2);

      // create dependencies
      Cache cache = mock(Cache.class);
      when(cache.getName()).thenReturn("testCache");

      pooledExecutorService = new ThreadPoolExecutor(0, 20, 0L,
                                                     TimeUnit.MILLISECONDS, new SynchronousQueue<>(),
                                                     getTestThreadFactory("Worker"),
                                                     new ThreadPoolExecutor.CallerRunsPolicy());

      StateTransferManager stateTransferManager = mock(StateTransferManager.class);
      LocalTopologyManager localTopologyManager = mock(LocalTopologyManager.class);
      CacheNotifier cacheNotifier = mock(CacheNotifier.class);
      RpcManager rpcManager = mock(RpcManager.class);
      Transport transport = mock(Transport.class);
      CommandsFactory commandsFactory = mock(CommandsFactory.class);
      PersistenceManager persistenceManager = mock(PersistenceManager.class);
      DataContainer dataContainer = mock(DataContainer.class);
      TransactionTable transactionTable = mock(TransactionTable.class);
      StateTransferLock stateTransferLock = mock(StateTransferLock.class);
      AsyncInterceptorChain interceptorChain = mock(AsyncInterceptorChain.class);
      InvocationContextFactory icf = mock(InvocationContextFactory.class);
      TotalOrderManager totalOrderManager = mock(TotalOrderManager.class);
      BlockingTaskAwareExecutorService remoteCommandsExecutor = mock(BlockingTaskAwareExecutorService.class);
      InternalConflictManager conflictManager = mock(InternalConflictManager.class);

      when(commandsFactory.buildStateRequestCommand(any(StateRequestCommand.Type.class), any(Address.class), anyInt(), any(SmallIntSet.class)))
         .thenAnswer(invocation-> new StateRequestCommand(ByteString.fromString("cache1"),
                                                          (StateRequestCommand.Type) invocation.getArguments()[0],
                                                          (Address) invocation.getArguments()[1],
                                                          (Integer) invocation.getArguments()[2],
                                                          (Set) invocation.getArguments()[3]));

      when(transport.getViewId()).thenReturn(1);
      when(rpcManager.getAddress()).thenReturn(addresses[0]);
      when(rpcManager.getTransport()).thenReturn(transport);

      final Map<Address, Set<Integer>> requestedSegments = CollectionFactory.makeConcurrentMap();
      final Set<Integer> flatRequestedSegments = new ConcurrentSkipListSet<>();
      when(rpcManager.invokeRemotely(any(Collection.class), any(StateRequestCommand.class), any(RpcOptions.class)))
            .thenAnswer(invocation -> {
               Collection<Address> recipients = (Collection<Address>) invocation.getArguments()[0];
               Address recipient = recipients.iterator().next();
               StateRequestCommand cmd = (StateRequestCommand) invocation.getArguments()[1];
               Map<Address, Response> results = new HashMap<>(1);
               if (cmd.getType().equals(StateRequestCommand.Type.GET_TRANSACTIONS)) {
                  results.put(recipient, SuccessfulResponse.create(new ArrayList<TransactionInfo>()));
                  Set<Integer> segments = cmd.getSegments();
                  requestedSegments.put(recipient, segments);
                  flatRequestedSegments.addAll(segments);
               } else if (cmd.getType().equals(StateRequestCommand.Type.START_STATE_TRANSFER)
                     || cmd.getType().equals(StateRequestCommand.Type.CANCEL_STATE_TRANSFER)) {
                  results.put(recipient, SuccessfulResponse.SUCCESSFUL_EMPTY_RESPONSE);
               }
               return results;
            });

      when(rpcManager.getRpcOptionsBuilder(any(ResponseMode.class))).thenAnswer(invocation -> {
         Object[] args = invocation.getArguments();
         return new RpcOptionsBuilder(10000, TimeUnit.MILLISECONDS, (ResponseMode) args[0],
                                      DeliverOrder.PER_SENDER);
      });


      // create state provider
      final StateConsumerImpl stateConsumer = new StateConsumerImpl();
      stateConsumer.init(cache, pooledExecutorService, stateTransferManager, localTopologyManager, interceptorChain, icf, configuration, rpcManager, null,
                         commandsFactory, persistenceManager, dataContainer, transactionTable, stateTransferLock, cacheNotifier,
                         totalOrderManager, remoteCommandsExecutor, new CommitManager(), new CommandAckCollector(), new TriangleOrderManager(0), null,
                         new HashFunctionPartitioner(), conflictManager);
      stateConsumer.start();

      final List<InternalCacheEntry> cacheEntries = new ArrayList<InternalCacheEntry>();
      Object key1 = new TestKey("key1", 0, ch1);
      Object key2 = new TestKey("key2", 0, ch1);
      cacheEntries.add(new ImmortalCacheEntry(key1, "value1"));
      cacheEntries.add(new ImmortalCacheEntry(key2, "value2"));
      when(dataContainer.iterator()).thenAnswer(new Answer<Iterator<InternalCacheEntry>>() {
         @Override
         public Iterator<InternalCacheEntry> answer(InvocationOnMock invocation) {
            return cacheEntries.iterator();
         }
      });
      when(transactionTable.getLocalTransactions()).thenReturn(Collections.<LocalTransaction>emptyList());
      when(transactionTable.getRemoteTransactions()).thenReturn(Collections.<RemoteTransaction>emptyList());

      assertFalse(stateConsumer.hasActiveTransfers());

      // node 4 leaves
      stateConsumer.onTopologyUpdate(new CacheTopology(1, 1, ch2, null, CacheTopology.Phase.NO_REBALANCE, ch2.getMembers(), persistentUUIDManager.mapAddresses(ch2.getMembers())), false);
      assertFalse(stateConsumer.hasActiveTransfers());

      // start a rebalance
      stateConsumer.onTopologyUpdate(new CacheTopology(2, 2, ch2, ch3, ch23, CacheTopology.Phase.READ_OLD_WRITE_ALL,
            ch23.getMembers(), persistentUUIDManager.mapAddresses(ch23.getMembers())), true);
      assertTrue(stateConsumer.hasActiveTransfers());

      // check that all segments have been requested
      Set<Integer> oldSegments = ch2.getSegmentsForOwner(addresses[0]);
      final Set<Integer> newSegments = ch3.getSegmentsForOwner(addresses[0]);
      newSegments.removeAll(oldSegments);
      log.debugf("Rebalancing. Added segments=%s, old segments=%s", newSegments, oldSegments);
      assertEquals(flatRequestedSegments, newSegments);

      // simulate a cluster state recovery and return to ch2
      Future<Object> future = fork(() -> {
         stateConsumer.onTopologyUpdate(new CacheTopology(3, 2, ch2, null, CacheTopology.Phase.NO_REBALANCE, ch2.getMembers(), persistentUUIDManager.mapAddresses(ch2.getMembers())), false);
         return null;
      });
      stateConsumer.onTopologyUpdate(new CacheTopology(3, 2, ch2, null, CacheTopology.Phase.NO_REBALANCE, ch2.getMembers(), persistentUUIDManager.mapAddresses(ch2.getMembers())), false);
      future.get();
      assertFalse(stateConsumer.hasActiveTransfers());


      // restart the rebalance
      requestedSegments.clear();
      stateConsumer.onTopologyUpdate(new CacheTopology(4, 4, ch2, ch3, ch23, CacheTopology.Phase.READ_OLD_WRITE_ALL,
            ch23.getMembers(), persistentUUIDManager.mapAddresses(ch23.getMembers())), true);
      assertTrue(stateConsumer.hasActiveTransfers());
      assertEquals(flatRequestedSegments, newSegments);

      // apply state
      ArrayList<StateChunk> stateChunks = new ArrayList<StateChunk>();
      for (Integer segment : newSegments) {
         stateChunks.add(new StateChunk(segment, Collections.<InternalCacheEntry>emptyList(), true));
      }
      stateConsumer.applyState(addresses[1], 2, stateChunks);

      stateConsumer.stop();
      assertFalse(stateConsumer.hasActiveTransfers());
   }
}
