/*
 *
 * 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;

import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.wal.WAL;

/**
 * Services a Store needs from a Region.
 * RegionServicesForStores class is the interface through which memstore access services at the
 * region level.
 * For example, when using alternative memory formats or due to compaction the memstore needs to
 * take occasional lock and update size counters at the region level.
 */
@InterfaceAudience.Private
public class RegionServicesForStores {

  private static final int POOL_SIZE = 10;
  private static final ThreadPoolExecutor INMEMORY_COMPACTION_POOL =
      new ThreadPoolExecutor(POOL_SIZE, POOL_SIZE, 60, TimeUnit.SECONDS,
          new LinkedBlockingQueue<>(),
          new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
              String name = Thread.currentThread().getName() + "-inmemoryCompactions-" +
                  System.currentTimeMillis();
              return new Thread(r, name);
            }
          });
  private final HRegion region;

  public RegionServicesForStores(HRegion region) {
    this.region = region;
  }

  public void blockUpdates() {
    region.blockUpdates();
  }

  public void unblockUpdates() {
    region.unblockUpdates();
  }

  public void addMemstoreSize(MemstoreSize size) {
    region.addAndGetMemstoreSize(size);
  }

  public HRegionInfo getRegionInfo() {
    return region.getRegionInfo();
  }

  public WAL getWAL() {
    return region.getWAL();
  }

  public ThreadPoolExecutor getInMemoryCompactionPool() { return INMEMORY_COMPACTION_POOL; }

  public long getMemstoreFlushSize() {
    return region.getMemstoreFlushSize();
  }

  public int getNumStores() {
    return region.getTableDesc().getColumnFamilyCount();
  }

  // methods for tests
  long getMemstoreSize() {
    return region.getMemstoreSize();
  }
}