/**
 * 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.protocolPB;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import com.google.common.base.Optional;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.ReconfigurationTaskStatus;
import org.apache.hadoop.conf.ReconfigurationUtil.PropertyChange;
import org.apache.hadoop.hdfs.client.BlockReportOptions;
import org.apache.hadoop.hdfs.protocol.BlockLocalPathInfo;
import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
import org.apache.hadoop.hdfs.protocol.HdfsBlocksMetadata;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.DeleteBlockPoolRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.DeleteBlockPoolResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetBlockLocalPathInfoRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetBlockLocalPathInfoResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetDatanodeInfoRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetDatanodeInfoResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetReconfigurationStatusConfigChangeProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetReconfigurationStatusRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetReconfigurationStatusResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetHdfsBlockLocationsRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetHdfsBlockLocationsResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetHdfsBlockLocationsResponseProto.Builder;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetReplicaVisibleLengthRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.GetReplicaVisibleLengthResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.RefreshNamenodesRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.RefreshNamenodesResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.ShutdownDatanodeRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.ShutdownDatanodeResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.StartReconfigurationRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.StartReconfigurationResponseProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.TriggerBlockReportRequestProto;
import org.apache.hadoop.hdfs.protocol.proto.ClientDatanodeProtocolProtos.TriggerBlockReportResponseProto;
import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
import org.apache.hadoop.security.proto.SecurityProtos.TokenProto;
import org.apache.hadoop.security.token.Token;

import com.google.common.primitives.Longs;
import com.google.protobuf.ByteString;
import com.google.protobuf.RpcController;
import com.google.protobuf.ServiceException;

/**
 * Implementation for protobuf service that forwards requests
 * received on {@link ClientDatanodeProtocolPB} to the
 * {@link ClientDatanodeProtocol} server implementation.
 */
@InterfaceAudience.Private
public class ClientDatanodeProtocolServerSideTranslatorPB implements
    ClientDatanodeProtocolPB {
  private final static RefreshNamenodesResponseProto REFRESH_NAMENODE_RESP =
      RefreshNamenodesResponseProto.newBuilder().build();
  private final static DeleteBlockPoolResponseProto DELETE_BLOCKPOOL_RESP =
      DeleteBlockPoolResponseProto.newBuilder().build();
  private final static ShutdownDatanodeResponseProto SHUTDOWN_DATANODE_RESP =
      ShutdownDatanodeResponseProto.newBuilder().build();
  private final static StartReconfigurationResponseProto START_RECONFIG_RESP =
      StartReconfigurationResponseProto.newBuilder().build();
  private final static TriggerBlockReportResponseProto TRIGGER_BLOCK_REPORT_RESP =
      TriggerBlockReportResponseProto.newBuilder().build();
  
  private final ClientDatanodeProtocol impl;

  public ClientDatanodeProtocolServerSideTranslatorPB(
      ClientDatanodeProtocol impl) {
    this.impl = impl;
  }

  @Override
  public GetReplicaVisibleLengthResponseProto getReplicaVisibleLength(
      RpcController unused, GetReplicaVisibleLengthRequestProto request)
      throws ServiceException {
    long len;
    try {
      len = impl.getReplicaVisibleLength(PBHelper.convert(request.getBlock()));
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return GetReplicaVisibleLengthResponseProto.newBuilder().setLength(len)
        .build();
  }

  @Override
  public RefreshNamenodesResponseProto refreshNamenodes(
      RpcController unused, RefreshNamenodesRequestProto request)
      throws ServiceException {
    try {
      impl.refreshNamenodes();
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return REFRESH_NAMENODE_RESP;
  }

  @Override
  public DeleteBlockPoolResponseProto deleteBlockPool(RpcController unused,
      DeleteBlockPoolRequestProto request) throws ServiceException {
    try {
      impl.deleteBlockPool(request.getBlockPool(), request.getForce());
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return DELETE_BLOCKPOOL_RESP;
  }

  @Override
  public GetBlockLocalPathInfoResponseProto getBlockLocalPathInfo(
      RpcController unused, GetBlockLocalPathInfoRequestProto request)
      throws ServiceException {
    BlockLocalPathInfo resp;
    try {
      resp = impl.getBlockLocalPathInfo(PBHelper.convert(request.getBlock()), PBHelper.convert(request.getToken()));
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return GetBlockLocalPathInfoResponseProto.newBuilder()
        .setBlock(PBHelper.convert(resp.getBlock()))
        .setLocalPath(resp.getBlockPath()).setLocalMetaPath(resp.getMetaPath())
        .build();
  }

  @Override
  public GetHdfsBlockLocationsResponseProto getHdfsBlockLocations(
      RpcController controller, GetHdfsBlockLocationsRequestProto request)
      throws ServiceException {
    HdfsBlocksMetadata resp;
    try {
      String poolId = request.getBlockPoolId();

      List<Token<BlockTokenIdentifier>> tokens = 
          new ArrayList<Token<BlockTokenIdentifier>>(request.getTokensCount());
      for (TokenProto b : request.getTokensList()) {
        tokens.add(PBHelper.convert(b));
      }
      long[] blockIds = Longs.toArray(request.getBlockIdsList());
      
      // Call the real implementation
      resp = impl.getHdfsBlocksMetadata(poolId, blockIds, tokens);
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    List<ByteString> volumeIdsByteStrings = 
        new ArrayList<ByteString>(resp.getVolumeIds().size());
    for (byte[] b : resp.getVolumeIds()) {
      volumeIdsByteStrings.add(ByteString.copyFrom(b));
    }
    // Build and return the response
    Builder builder = GetHdfsBlockLocationsResponseProto.newBuilder();
    builder.addAllVolumeIds(volumeIdsByteStrings);
    builder.addAllVolumeIndexes(resp.getVolumeIndexes());
    return builder.build();
  }

  @Override
  public ShutdownDatanodeResponseProto shutdownDatanode(
      RpcController unused, ShutdownDatanodeRequestProto request)
      throws ServiceException {
    try {
      impl.shutdownDatanode(request.getForUpgrade());
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return SHUTDOWN_DATANODE_RESP;
  }

  public GetDatanodeInfoResponseProto getDatanodeInfo(RpcController unused,
      GetDatanodeInfoRequestProto request) throws ServiceException {
    GetDatanodeInfoResponseProto res;
    try {
      res = GetDatanodeInfoResponseProto.newBuilder()
          .setLocalInfo(PBHelper.convert(impl.getDatanodeInfo())).build();
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return res;
  }

  @Override
  public StartReconfigurationResponseProto startReconfiguration(
      RpcController unused, StartReconfigurationRequestProto request)
    throws ServiceException {
    try {
      impl.startReconfiguration();
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return START_RECONFIG_RESP;
  }

  @Override
  public GetReconfigurationStatusResponseProto getReconfigurationStatus(
      RpcController unused, GetReconfigurationStatusRequestProto request)
      throws ServiceException {
    GetReconfigurationStatusResponseProto.Builder builder =
        GetReconfigurationStatusResponseProto.newBuilder();
    try {
      ReconfigurationTaskStatus status = impl.getReconfigurationStatus();
      builder.setStartTime(status.getStartTime());
      if (status.stopped()) {
        builder.setEndTime(status.getEndTime());
        assert status.getStatus() != null;
        for (Map.Entry<PropertyChange, Optional<String>> result :
            status.getStatus().entrySet()) {
          GetReconfigurationStatusConfigChangeProto.Builder changeBuilder =
              GetReconfigurationStatusConfigChangeProto.newBuilder();
          PropertyChange change = result.getKey();
          changeBuilder.setName(change.prop);
          changeBuilder.setOldValue(change.oldVal != null ? change.oldVal : "");
          if (change.newVal != null) {
            changeBuilder.setNewValue(change.newVal);
          }
          if (result.getValue().isPresent()) {
            // Get full stack trace.
            changeBuilder.setErrorMessage(result.getValue().get());
          }
          builder.addChanges(changeBuilder);
        }
      }
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return builder.build();
  }

  @Override
  public TriggerBlockReportResponseProto triggerBlockReport(
      RpcController unused, TriggerBlockReportRequestProto request)
          throws ServiceException {
    try {
      impl.triggerBlockReport(new BlockReportOptions.Factory().
          setIncremental(request.getIncremental()).build());
    } catch (IOException e) {
      throw new ServiceException(e);
    }
    return TRIGGER_BLOCK_REPORT_RESP;
  }
}