/**
    * Copyright The Apache Software Foundation
    *
    * 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.rsgroup;
  
  import com.google.common.collect.Maps;
  import com.google.common.collect.Sets;
  
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.ConnectionFactory;
  import org.apache.hadoop.hbase.client.Result;
  import org.apache.hadoop.hbase.client.Scan;
  import org.apache.hadoop.hbase.client.Table;
  import org.apache.hadoop.hbase.exceptions.DeserializationException;
  import org.apache.hadoop.hbase.net.Address;
  import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
  import org.apache.hadoop.hbase.protobuf.generated.RSGroupProtos;
  import org.apache.hadoop.hbase.zookeeper.ZKUtil;
  import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
  import org.apache.zookeeper.KeeperException;
  import org.junit.Assert;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  
  public class VerifyingRSGroupAdminClient implements RSGroupAdmin {
    private Table table;
    private ZooKeeperWatcher zkw;
    private RSGroupAdmin wrapped;
  
    public VerifyingRSGroupAdminClient(RSGroupAdmin RSGroupAdmin, Configuration conf)
        throws IOException {
      wrapped = RSGroupAdmin;
      table = ConnectionFactory.createConnection(conf).getTable(RSGroupInfoManager.RSGROUP_TABLE_NAME);
      zkw = new ZooKeeperWatcher(conf, this.getClass().getSimpleName(), null);
    }
  
    @Override
    public void addRSGroup(String groupName) throws IOException {
      wrapped.addRSGroup(groupName);
      verify();
    }
  
    @Override
    public RSGroupInfo getRSGroupInfo(String groupName) throws IOException {
      return wrapped.getRSGroupInfo(groupName);
    }
  
    @Override
    public RSGroupInfo getRSGroupInfoOfTable(TableName tableName) throws IOException {
      return wrapped.getRSGroupInfoOfTable(tableName);
    }
  
    @Override
    public void moveServers(Set<Address> servers, String targetGroup) throws IOException {
      wrapped.moveServers(servers, targetGroup);
      verify();
    }
  
    @Override
    public void moveTables(Set<TableName> tables, String targetGroup) throws IOException {
      wrapped.moveTables(tables, targetGroup);
      verify();
    }
  
    @Override
    public void removeRSGroup(String name) throws IOException {
      wrapped.removeRSGroup(name);
      verify();
    }
  
    @Override
    public boolean balanceRSGroup(String name) throws IOException {
      return wrapped.balanceRSGroup(name);
    }
  
    @Override
    public List<RSGroupInfo> listRSGroups() throws IOException {
      return wrapped.listRSGroups();
   }
 
   @Override
   public RSGroupInfo getRSGroupOfServer(Address server) throws IOException {
     return wrapped.getRSGroupOfServer(server);
   }
 
   @Override
   public void removeServers(Set<Address> servers) throws IOException {
     wrapped.removeServers(servers);
     verify();
   }
 
   @Override
   public void renameRSGroup(String oldName, String newName) throws IOException {
     wrapped.renameRSGroup(oldName, newName);
     verify();
   }
 
   public void verify() throws IOException {
     Map<String, RSGroupInfo> groupMap = Maps.newHashMap();
     Set<RSGroupInfo> zList = Sets.newHashSet();
 
     for (Result result : table.getScanner(new Scan())) {
       RSGroupProtos.RSGroupInfo proto =
           RSGroupProtos.RSGroupInfo.parseFrom(
               result.getValue(
                   RSGroupInfoManager.META_FAMILY_BYTES,
                   RSGroupInfoManager.META_QUALIFIER_BYTES));
       groupMap.put(proto.getName(), RSGroupProtobufUtil.toGroupInfo(proto));
     }
     Assert.assertEquals(Sets.newHashSet(groupMap.values()),
         Sets.newHashSet(wrapped.listRSGroups()));
     try {
       String groupBasePath = ZKUtil.joinZNode(zkw.baseZNode, "rsgroup");
       for(String znode: ZKUtil.listChildrenNoWatch(zkw, groupBasePath)) {
         byte[] data = ZKUtil.getData(zkw, ZKUtil.joinZNode(groupBasePath, znode));
         if(data.length > 0) {
           ProtobufUtil.expectPBMagicPrefix(data);
           ByteArrayInputStream bis = new ByteArrayInputStream(
               data, ProtobufUtil.lengthOfPBMagic(), data.length);
           zList.add(RSGroupProtobufUtil.toGroupInfo(RSGroupProtos.RSGroupInfo.parseFrom(bis)));
         }
       }
       Assert.assertEquals(zList.size(), groupMap.size());
       for(RSGroupInfo RSGroupInfo : zList) {
         Assert.assertTrue(groupMap.get(RSGroupInfo.getName()).equals(RSGroupInfo));
       }
     } catch (KeeperException e) {
       throw new IOException("ZK verification failed", e);
     } catch (DeserializationException e) {
       throw new IOException("ZK verification failed", e);
     } catch (InterruptedException e) {
       throw new IOException("ZK verification failed", e);
     }
   }
 
   @Override
   public void moveServersAndTables(Set<Address> servers, Set<TableName> tables,
       String targetGroup) throws IOException {
     wrapped.moveServersAndTables(servers, tables, targetGroup);
     verify();
   }
 
   @Override
   public void close() throws IOException {
   }
 }