/*
    * 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.commons.dbcp2.datasources;
  
  import java.sql.Connection;
  import java.sql.SQLException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.EventListener;
  import java.util.List;
  
  import javax.sql.ConnectionEvent;
  import javax.sql.ConnectionEventListener;
  import javax.sql.PooledConnection;
  import javax.sql.StatementEventListener;
  
  /**
   * PooledConnection implementation that wraps a driver-supplied
   * PooledConnection and proxies events, allowing behavior to be
   * modified to simulate behavior of different implementations.
   */
  public class PooledConnectionProxy implements PooledConnection,
      ConnectionEventListener {
  
      protected PooledConnection delegate;
  
      /**
       * ConnectionEventListeners
       */
      private final List<EventListener> eventListeners = Collections.synchronizedList(new ArrayList<>());
  
      /**
       * True means we will (dubiously) notify listeners with a
       * ConnectionClosed event when this (i.e. the PooledConnection itself)
       * is closed
       */
      private boolean notifyOnClose;
  
      public PooledConnectionProxy(final PooledConnection pooledConnection) {
          this.delegate = pooledConnection;
          pooledConnection.addConnectionEventListener(this);
      }
  
      /**
       * Add event listeners.
       */
      @Override
      public void addConnectionEventListener(final ConnectionEventListener listener) {
          if (!eventListeners.contains(listener)) {
              eventListeners.add(listener);
          }
      }
  
      @Override
      public void addStatementEventListener(final StatementEventListener listener) {
          if (!eventListeners.contains(listener)) {
              eventListeners.add(listener);
          }
      }
  
      /**
       * If notifyOnClose is on, notify listeners
       */
      @Override
      public void close() throws SQLException {
          delegate.close();
          if (isNotifyOnClose()) {
             notifyListeners();
          }
      }
  
      /**
       * Pass closed events on to listeners
       */
      @Override
      public void connectionClosed(final ConnectionEvent event) {
          notifyListeners();
      }
  
      /**
       * Pass error events on to listeners
       */
      @Override
     public void connectionErrorOccurred(final ConnectionEvent event) {
         final Object[] listeners = eventListeners.toArray();
         for (final Object listener : listeners) {
             ((ConnectionEventListener) listener).connectionErrorOccurred(event);
         }
     }
 
     @Override
     public Connection getConnection() throws SQLException {
         return delegate.getConnection();
     }
 
     /**
      * Expose listeners
      */
     public Collection<EventListener> getListeners() {
         return eventListeners;
     }
 
     public boolean isNotifyOnClose() {
         return notifyOnClose;
     }
 
     /**
      * sends a connectionClosed event to listeners.
      */
     void notifyListeners() {
         final ConnectionEvent event = new ConnectionEvent(this);
         final Object[] listeners = eventListeners.toArray();
         for (final Object listener : listeners) {
             ((ConnectionEventListener) listener).connectionClosed(event);
         }
     }
 
     /**
      * Remove event listeners.
      */
     @Override
     public void removeConnectionEventListener(final ConnectionEventListener listener) {
         eventListeners.remove(listener);
     }
 
     @Override
     public void removeStatementEventListener(final StatementEventListener listener) {
         eventListeners.remove(listener);
     }
 
     public void setNotifyOnClose(final boolean notifyOnClose) {
         this.notifyOnClose = notifyOnClose;
     }
 
     /**
      * Generate a connection error event
      */
     public void throwConnectionError() {
         final ConnectionEvent event = new ConnectionEvent(this);
         connectionErrorOccurred(event);
     }
 
 }