content: /*
   * 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.ambari.server.state.alert;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  
  import com.google.inject.Singleton;
  
  /**
   * The {@link AggregateDefinitionMapping} is used to keep an in-memory mapping
   * of all of the {@link AlertDefinition}s that have aggregate definitions
   * associated with them.
   */
  @Singleton
  public class AggregateDefinitionMapping {
    /**
     * In-memory mapping of cluster ID to definition name / aggregate definition.
     * This is used for fast lookups when receiving events.
     */
    private Map<Long, Map<String, AlertDefinition>> m_aggregateMap =
      new ConcurrentHashMap<>();
  
    /**
     * Constructor.
     *
     */
    public AggregateDefinitionMapping() {
    }
  
    /**
     * Gets an aggregate definition based on a given alert definition name.
     *
     * @param clusterId
     *          the ID of the cluster that the definition is bound to.
     * @param name
     *          the unique name of the definition.
     * @return the aggregate definition, or {@code null} if none.
     */
    public AlertDefinition getAggregateDefinition(long clusterId, String name) {
      Long id = Long.valueOf(clusterId);
      if (!m_aggregateMap.containsKey(id)) {
        return null;
      }
  
      if (!m_aggregateMap.get(id).containsKey(name)) {
        return null;
      }
  
      return m_aggregateMap.get(id).get(name);
    }
  
    /**
     * Adds a mapping for a new aggregate definition.
     *
     * @param clusterId
     *          the ID of the cluster that the definition is bound to.
     * @param definition
     *          the aggregate definition to register (not {@code null}).
     */
    public void registerAggregate(long clusterId, AlertDefinition definition) {
      Long id = Long.valueOf(clusterId);
  
      if (!m_aggregateMap.containsKey(id)) {
        m_aggregateMap.put(id, new HashMap<>());
      }
  
      Map<String, AlertDefinition> map = m_aggregateMap.get(id);
  
      AggregateSource as = (AggregateSource) definition.getSource();
  
      map.put(as.getAlertName(), definition);
    }
  
    /**
     * Removes the associated aggregate for the specified aggregated definition.
     *
     * @param clusterId
     *          the ID of the cluster that the definition is bound to.
     * @param aggregatedDefinitonName
     *          the unique name of the definition for which aggregates should be
     *          unassociated (not {@code null}).
     */
    public void removeAssociatedAggregate(long clusterId,
        String aggregatedDefinitonName) {
      Long id = Long.valueOf(clusterId);
  
      if (!m_aggregateMap.containsKey(id)) {
        return;
      }
  
      Map<String, AlertDefinition> map = m_aggregateMap.get(id);
      map.remove(aggregatedDefinitonName);
    }
  
    /**
     * Gets a copy of all of the aggregate definitions for the specified cluster.
     *
     * @param clusterId
     *          the cluster ID
     * @return the list of all aggregate definitions
     */
    public List<AlertDefinition> getAggregateDefinitions(long clusterId) {
      if (!m_aggregateMap.containsKey(clusterId)) {
        return Collections.emptyList();
      }
  
      Map<String, AlertDefinition> map = m_aggregateMap.get(clusterId);
      return new ArrayList<>(map.values());
    }
  
    /**
     * Gets a copy of all of the alerts that have aggregates defined for them.
     *
     * @param clusterId
     *          the cluster ID
     * @return the list of all alerts with aggregate definitions
     */
    public List<String> getAlertsWithAggregates(long clusterId) {
      if (!m_aggregateMap.containsKey(clusterId)) {
        return Collections.emptyList();
      }
  
      Map<String, AlertDefinition> map = m_aggregateMap.get(clusterId);
      return new ArrayList<>(map.keySet());
    }
  }
  