/**
    * 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.replication;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.hbase.Cell;
  import org.apache.hadoop.hbase.CellUtil;
  import org.apache.hadoop.hbase.protobuf.generated.WALProtos.BulkLoadDescriptor;
  import org.apache.hadoop.hbase.protobuf.generated.WALProtos.StoreDescriptor;
  import org.apache.hadoop.hbase.regionserver.wal.WALEdit;
  
  import com.google.common.base.Predicate;
  
  public class BulkLoadCellFilter {
    private static final Log LOG = LogFactory.getLog(BulkLoadCellFilter.class);
  
    /**
     * Filters the bulk load cell using the supplied predicate.
     * @param cell The WAL cell to filter.
     * @param famPredicate Returns true of given family should be removed.
     * @return The filtered cell.
     */
    public Cell filterCell(Cell cell, Predicate<byte[]> famPredicate) {
      byte[] fam;
      BulkLoadDescriptor bld = null;
      try {
        bld = WALEdit.getBulkLoadDescriptor(cell);
      } catch (IOException e) {
        LOG.warn("Failed to get bulk load events information from the WAL file.", e);
        return cell;
      }
      List<StoreDescriptor> storesList = bld.getStoresList();
      // Copy the StoreDescriptor list and update it as storesList is a unmodifiableList
      List<StoreDescriptor> copiedStoresList = new ArrayList<StoreDescriptor>(storesList);
      Iterator<StoreDescriptor> copiedStoresListIterator = copiedStoresList.iterator();
      boolean anyStoreRemoved = false;
      while (copiedStoresListIterator.hasNext()) {
        StoreDescriptor sd = copiedStoresListIterator.next();
        fam = sd.getFamilyName().toByteArray();
        if (famPredicate.apply(fam)) {
          copiedStoresListIterator.remove();
          anyStoreRemoved = true;
        }
      }
  
      if (!anyStoreRemoved) {
        return cell;
      } else if (copiedStoresList.isEmpty()) {
        return null;
      }
      BulkLoadDescriptor.Builder newDesc =
          BulkLoadDescriptor.newBuilder().setTableName(bld.getTableName())
              .setEncodedRegionName(bld.getEncodedRegionName())
              .setBulkloadSeqNum(bld.getBulkloadSeqNum());
      newDesc.addAllStores(copiedStoresList);
      BulkLoadDescriptor newBulkLoadDescriptor = newDesc.build();
      return CellUtil.createCell(CellUtil.cloneRow(cell), WALEdit.METAFAMILY, WALEdit.BULK_LOAD,
          cell.getTimestamp(), cell.getTypeByte(), newBulkLoadDescriptor.toByteArray());
    }
  }