/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.ozone.om.request.key;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import org.apache.hadoop.ozone.om.ratis.utils.OzoneManagerDoubleBufferHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


import org.apache.hadoop.fs.FileEncryptionInfo;
import org.apache.hadoop.hdds.protocol.proto.HddsProtos;
import org.apache.hadoop.hdds.scm.container.common.helpers.ExcludeList;
import org.apache.hadoop.ozone.audit.OMAction;
import org.apache.hadoop.ozone.om.OMMetadataManager;
import org.apache.hadoop.ozone.om.OMMetrics;
import org.apache.hadoop.ozone.om.OzoneManager;
import org.apache.hadoop.ozone.om.helpers.OmBucketInfo;
import org.apache.hadoop.ozone.om.helpers.OmKeyInfo;
import org.apache.hadoop.ozone.om.helpers.OmKeyLocationInfo;
import org.apache.hadoop.ozone.om.response.OMClientResponse;
import org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos
    .CreateKeyRequest;
import org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos
    .KeyArgs;
import org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos
    .OMRequest;
import org.apache.hadoop.util.Time;
import org.apache.hadoop.hdds.utils.UniqueId;

import static org.apache.hadoop.ozone.om.lock.OzoneManagerLock.Resource.BUCKET_LOCK;
/**
 * Handles CreateKey request.
 */

public class OMKeyCreateRequest extends OMKeyRequest {
  private static final Logger LOG =
      LoggerFactory.getLogger(OMKeyCreateRequest.class);

  public OMKeyCreateRequest(OMRequest omRequest) {
    super(omRequest);
  }

  @Override
  public OMRequest preExecute(OzoneManager ozoneManager) throws IOException {
    CreateKeyRequest createKeyRequest = getOmRequest().getCreateKeyRequest();
    Preconditions.checkNotNull(createKeyRequest);

    KeyArgs keyArgs = createKeyRequest.getKeyArgs();

    // We cannot allocate block for multipart upload part when
    // createMultipartKey is called, as we will not know type and factor with
    // which initiateMultipartUpload has started for this key. When
    // allocateBlock call happen's we shall know type and factor, as we set
    // the type and factor read from multipart table, and set the KeyInfo in
    // validateAndUpdateCache and return to the client. TODO: See if we can fix
    //  this. We do not call allocateBlock in openKey for multipart upload.

    CreateKeyRequest.Builder newCreateKeyRequest = null;
    KeyArgs.Builder newKeyArgs = null;
    if (!keyArgs.getIsMultipartKey()) {

      long scmBlockSize = ozoneManager.getScmBlockSize();

      // NOTE size of a key is not a hard limit on anything, it is a value that
      // client should expect, in terms of current size of key. If client sets
      // a value, then this value is used, otherwise, we allocate a single
      // block which is the current size, if read by the client.
      final long requestedSize = keyArgs.getDataSize() > 0 ?
          keyArgs.getDataSize() : scmBlockSize;

      boolean useRatis = ozoneManager.shouldUseRatis();

      HddsProtos.ReplicationFactor factor = keyArgs.getFactor();
      if (factor == null) {
        factor = useRatis ? HddsProtos.ReplicationFactor.THREE :
            HddsProtos.ReplicationFactor.ONE;
      }

      HddsProtos.ReplicationType type = keyArgs.getType();
      if (type == null) {
        type = useRatis ? HddsProtos.ReplicationType.RATIS :
            HddsProtos.ReplicationType.STAND_ALONE;
      }

      // TODO: Here we are allocating block with out any check for
      //  bucket/key/volume or not and also with out any authorization checks.
      //  As for a client for the first time this can be executed on any OM,
      //  till leader is identified.

      List< OmKeyLocationInfo > omKeyLocationInfoList =
          allocateBlock(ozoneManager.getScmClient(),
              ozoneManager.getBlockTokenSecretManager(), type, factor,
              new ExcludeList(), requestedSize, scmBlockSize,
              ozoneManager.getPreallocateBlocksMax(),
              ozoneManager.isGrpcBlockTokenEnabled(),
              ozoneManager.getOMNodeId());

      newKeyArgs = keyArgs.toBuilder().setModificationTime(Time.now())
              .setType(type).setFactor(factor)
              .setDataSize(requestedSize);

      newKeyArgs.addAllKeyLocations(omKeyLocationInfoList.stream()
          .map(OmKeyLocationInfo::getProtobuf).collect(Collectors.toList()));
    } else {
      newKeyArgs = keyArgs.toBuilder().setModificationTime(Time.now());
    }

    newCreateKeyRequest =
        createKeyRequest.toBuilder().setKeyArgs(newKeyArgs)
            .setClientID(UniqueId.next());

    return getOmRequest().toBuilder()
        .setCreateKeyRequest(newCreateKeyRequest).setUserInfo(getUserInfo())
        .build();
  }

  @Override
  public OMClientResponse validateAndUpdateCache(OzoneManager ozoneManager,
      long transactionLogIndex,
      OzoneManagerDoubleBufferHelper ozoneManagerDoubleBufferHelper) {
    CreateKeyRequest createKeyRequest = getOmRequest().getCreateKeyRequest();


    KeyArgs keyArgs = createKeyRequest.getKeyArgs();

    String volumeName = keyArgs.getVolumeName();
    String bucketName = keyArgs.getBucketName();
    String keyName = keyArgs.getKeyName();

    OMMetrics omMetrics = ozoneManager.getMetrics();
    omMetrics.incNumKeyAllocates();

    OMMetadataManager omMetadataManager = ozoneManager.getMetadataManager();
    OmKeyInfo omKeyInfo = null;
    final List< OmKeyLocationInfo > locations = new ArrayList<>();
    Optional<FileEncryptionInfo> encryptionInfo = Optional.absent();
    IOException exception = null;
    boolean acquireLock = false;
    OMClientResponse omClientResponse = null;
    try {
      // check Acl
      checkBucketAcls(ozoneManager, volumeName, bucketName, keyName);

      acquireLock = omMetadataManager.getLock().acquireWriteLock(BUCKET_LOCK,
          volumeName, bucketName);
      validateBucketAndVolume(omMetadataManager, volumeName, bucketName);
      //TODO: We can optimize this get here, if getKmsProvider is null, then
      // bucket encryptionInfo will be not set. If this assumption holds
      // true, we can avoid get from bucket table.

      OmBucketInfo bucketInfo = omMetadataManager.getBucketTable().get(
              omMetadataManager.getBucketKey(volumeName, bucketName));

      encryptionInfo = getFileEncryptionInfo(ozoneManager, bucketInfo);

      omKeyInfo = prepareKeyInfo(omMetadataManager, keyArgs,
          omMetadataManager.getOzoneKey(volumeName, bucketName, keyName),
          keyArgs.getDataSize(), locations, encryptionInfo.orNull(),
          ozoneManager.getPrefixManager(), bucketInfo);
      omClientResponse = prepareCreateKeyResponse(keyArgs, omKeyInfo,
          locations, encryptionInfo.orNull(), exception,
          createKeyRequest.getClientID(), transactionLogIndex, volumeName,
          bucketName, keyName, ozoneManager, OMAction.ALLOCATE_KEY,
          ozoneManager.getPrefixManager(), bucketInfo);
    } catch (IOException ex) {
      exception = ex;
      omClientResponse = prepareCreateKeyResponse(keyArgs, omKeyInfo, locations,
          encryptionInfo.orNull(), exception, createKeyRequest.getClientID(),
          transactionLogIndex, volumeName, bucketName, keyName, ozoneManager,
          OMAction.ALLOCATE_KEY, ozoneManager.getPrefixManager(), null);
    } finally {
      if (omClientResponse != null) {
        omClientResponse.setFlushFuture(
            ozoneManagerDoubleBufferHelper.add(omClientResponse,
                transactionLogIndex));
      }
      if (acquireLock) {
        omMetadataManager.getLock().releaseWriteLock(BUCKET_LOCK, volumeName,
            bucketName);
      }
    }

    return omClientResponse;
  }

}