/**
    * 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.regionserver.compactions;
  
  import java.io.IOException;
  import java.util.List;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.regionserver.DateTieredMultiFileWriter;
  import org.apache.hadoop.hbase.regionserver.InternalScanner;
  import org.apache.hadoop.hbase.regionserver.Store;
  import org.apache.hadoop.hbase.regionserver.StoreFile;
  import org.apache.hadoop.hbase.regionserver.throttle.ThroughputController;
  import org.apache.hadoop.hbase.security.User;
  
  /**
   * This compactor will generate StoreFile for different time ranges.
   */
  @InterfaceAudience.Private
  public class DateTieredCompactor extends AbstractMultiOutputCompactor<DateTieredMultiFileWriter> {
  
    private static final Log LOG = LogFactory.getLog(DateTieredCompactor.class);
  
    public DateTieredCompactor(Configuration conf, Store store) {
      super(conf, store);
    }
  
    private boolean needEmptyFile(CompactionRequest request) {
      // if we are going to compact the last N files, then we need to emit an empty file to retain the
      // maxSeqId if we haven't written out anything.
      return StoreFile.getMaxSequenceIdInList(request.getFiles()) == store.getMaxSequenceId();
    }
  
    public List<Path> compact(final CompactionRequest request, final List<Long> lowerBoundaries,
        ThroughputController throughputController, User user) throws IOException {
      if (LOG.isDebugEnabled()) {
        LOG.debug("Executing compaction with " + lowerBoundaries.size()
            + "windows, lower boundaries: " + lowerBoundaries);
      }
  
      return compact(request, defaultScannerFactory,
        new CellSinkFactory<DateTieredMultiFileWriter>() {
  
          @Override
          public DateTieredMultiFileWriter createWriter(InternalScanner scanner, FileDetails fd,
              boolean shouldDropBehind) throws IOException {
            DateTieredMultiFileWriter writer = new DateTieredMultiFileWriter(lowerBoundaries,
                needEmptyFile(request));
            initMultiWriter(writer, scanner, fd, shouldDropBehind);
            return writer;
          }
        }, throughputController, user);
    }
  
    @Override
    protected List<Path> commitWriter(DateTieredMultiFileWriter writer, FileDetails fd,
        CompactionRequest request) throws IOException {
      return writer.commitWriters(fd.maxSeqId, request.isAllFiles(), request.getFiles());
    }
  }