/**
 * 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.
 */
package org.apache.hadoop.hdfs.server.blockmanagement;

import io.hops.common.INodeUtil;
import io.hops.exception.StorageException;
import io.hops.metadata.hdfs.entity.INodeIdentifier;
import io.hops.transaction.handler.HDFSOperationType;
import io.hops.transaction.handler.HopsTransactionalRequestHandler;
import io.hops.transaction.lock.LockFactory;
import io.hops.transaction.lock.TransactionLocks;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.Block;
import org.apache.hadoop.hdfs.server.common.GenerationStamp;
import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
import org.junit.Test;

import java.io.IOException;

import static org.junit.Assert.assertEquals;

/**
 * Test if FSNamesystem handles heartbeat right
 */
public class TestComputeInvalidateWork {
  /**
   * Test if {@link FSNamesystem#computeInvalidateWork(int)}
   * can schedule invalidate work correctly
   */
  @Test
  public void testCompInvalidate() throws Exception {
    final Configuration conf = new HdfsConfiguration();
    final int NUM_OF_DATANODES = 3;
    conf.setInt(DFSConfigKeys.DFS_NAMENODE_REPLICATION_INTERVAL_KEY,
        Integer.MAX_VALUE);

    final MiniDFSCluster cluster =
        new MiniDFSCluster.Builder(conf).numDataNodes(NUM_OF_DATANODES).build();
    try {
      cluster.waitActive();
      final FSNamesystem namesystem = cluster.getNamesystem();
      final BlockManager bm = namesystem.getBlockManager();
      final int blockInvalidateLimit =
          bm.getDatanodeManager().blockInvalidateLimit;
      final DatanodeDescriptor[] nodes =
          bm.getDatanodeManager().getHeartbeatManager().getDatanodes();
      assertEquals(nodes.length, NUM_OF_DATANODES);

      for (int i = 0; i < nodes.length; i++) {
        for (int j = 0; j < 3 * blockInvalidateLimit + 1; j++) {
          Block block = new Block(i * (blockInvalidateLimit + 1) + j, 0,
              GenerationStamp.FIRST_VALID_STAMP);
          addToInvalidates(bm, block, nodes[i], namesystem);
        }
      }

      assertEquals(blockInvalidateLimit * NUM_OF_DATANODES,
          bm.computeInvalidateWork(NUM_OF_DATANODES + 1));
      assertEquals(blockInvalidateLimit * NUM_OF_DATANODES,
          bm.computeInvalidateWork(NUM_OF_DATANODES));
      assertEquals(blockInvalidateLimit * (NUM_OF_DATANODES - 1),
          bm.computeInvalidateWork(NUM_OF_DATANODES - 1));
      int workCount = bm.computeInvalidateWork(1);
      if (workCount == 1) {
        assertEquals(blockInvalidateLimit + 1, bm.computeInvalidateWork(2));
      } else {
        assertEquals(workCount, blockInvalidateLimit);
        assertEquals(2, bm.computeInvalidateWork(2));
      }

    } finally {
      cluster.shutdown();
    }
  }
  
  private void addToInvalidates(final BlockManager bm, final Block block,
      final DatanodeDescriptor node, final FSNamesystem namesystem)
      throws IOException {
    new HopsTransactionalRequestHandler(HDFSOperationType.COMP_INVALIDATE) {
      INodeIdentifier inodeIdentifier;

      @Override
      public void setUp() throws StorageException, IOException {
        inodeIdentifier = INodeUtil.resolveINodeFromBlock(block);
      }

      @Override
      public void acquireLock(TransactionLocks locks) throws IOException {
        LockFactory lf = LockFactory.getInstance();
        locks
            .add(lf.getIndividualBlockLock(block.getBlockId(), inodeIdentifier))
            .add(lf.getBlockRelated(LockFactory.BLK.IV));
      }

      @Override
      public Object performTask() throws StorageException, IOException {
        bm.addToInvalidates(block, node);
        return null;
      }
    }.handle(namesystem);
  }
}