/**
    * 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.hbase.master;
  
  import static org.junit.Assert.assertNotSame;
  
  import org.apache.hadoop.hbase.exceptions.DeserializationException;
  import org.apache.hadoop.hbase.HRegionInfo;
  import org.apache.hadoop.hbase.RegionTransition;
  import org.apache.hadoop.hbase.ServerName;
  import org.apache.hadoop.hbase.executor.EventType;
  import org.apache.hadoop.hbase.master.RegionState.State;
  import org.apache.hadoop.hbase.zookeeper.ZKAssign;
  import org.apache.hadoop.hbase.zookeeper.ZKUtil;
  import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
  import org.apache.zookeeper.KeeperException;
  
  /**
   * Package scoped mocking utility.
   */
  public class Mocking {
  
    static void waitForRegionFailedToCloseAndSetToPendingClose(
        AssignmentManager am, HRegionInfo hri) throws InterruptedException {
      // Since region server is fake, sendRegionClose will fail, and closing
      // region will fail. For testing purpose, moving it back to pending close
      boolean wait = true;
      while (wait) {
        RegionState state = am.getRegionStates().getRegionState(hri);
        if (state != null && state.isFailedClose()){
          am.getRegionStates().updateRegionState(hri, State.PENDING_CLOSE);
          wait = false;
        } else {
          Thread.sleep(1);
        }
      }
    }
  
    /**
     * Verifies that the specified region is in the specified state in ZooKeeper.
     * <p>
     * Returns true if region is in transition and in the specified state in
     * ZooKeeper.  Returns false if the region does not exist in ZK or is in
     * a different state.
     * <p>
     * Method synchronizes() with ZK so will yield an up-to-date result but is
     * a slow read.
     * @param zkw
     * @param region
     * @param expectedState
     * @return true if region exists and is in expected state
     * @throws DeserializationException
     */
    static boolean verifyRegionState(ZooKeeperWatcher zkw, HRegionInfo region, EventType expectedState)
    throws KeeperException, DeserializationException {
      String encoded = region.getEncodedName();
  
      String node = ZKAssign.getNodeName(zkw, encoded);
      zkw.syncOrTimeout(node);
  
      // Read existing data of the node
      byte [] existingBytes = null;
      try {
        existingBytes = ZKUtil.getDataAndWatch(zkw, node);
      } catch (KeeperException.NoNodeException nne) {
        return false;
      } catch (KeeperException e) {
        throw e;
      }
      if (existingBytes == null) return false;
      RegionTransition rt = RegionTransition.parseFrom(existingBytes);
      return rt.getEventType().equals(expectedState);
    }
  }