/*
 *
 * 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.client;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.util.Bytes;

/**
 * Container for Actions (i.e. Get, Delete, or Put), which are grouped by
 * regionName. Intended to be used with HConnectionManager.processBatch()
 */
@InterfaceAudience.Private
public final class MultiAction<R> {
  // TODO: This class should not be visible outside of the client package.

  // map of regions to lists of puts/gets/deletes for that region.
  public Map<byte[], List<Action<R>>> actions =
    new TreeMap<byte[], List<Action<R>>>(Bytes.BYTES_COMPARATOR);

  private long nonceGroup = HConstants.NO_NONCE;

  public MultiAction() {
    super();
  }

  /**
   * Get the total number of Actions
   *
   * @return total number of Actions for all groups in this container.
   */
  public int size() {
    int size = 0;
    for (List<?> l : actions.values()) {
      size += l.size();
    }
    return size;
  }

  /**
   * Add an Action to this container based on it's regionName. If the regionName
   * is wrong, the initial execution will fail, but will be automatically
   * retried after looking up the correct region.
   *
   * @param regionName
   * @param a
   */
  public void add(byte[] regionName, Action<R> a) {
    List<Action<R>> rsActions = actions.get(regionName);
    if (rsActions == null) {
      rsActions = new ArrayList<Action<R>>();
      actions.put(regionName, rsActions);
    }
    rsActions.add(a);
  }

  public void setNonceGroup(long nonceGroup) {
    this.nonceGroup = nonceGroup;
  }

  public Set<byte[]> getRegions() {
    return actions.keySet();
  }

  /**
   * @return All actions from all regions in this container
   */
  public List<Action<R>> allActions() {
    List<Action<R>> res = new ArrayList<Action<R>>();
    for (List<Action<R>> lst : actions.values()) {
      res.addAll(lst);
    }
    return res;
  }

  public boolean hasNonceGroup() {
    return nonceGroup != HConstants.NO_NONCE;
  }

  public long getNonceGroup() {
    return this.nonceGroup;
  }
}