/*
    *    Copyright 2009-2024 the original author or authors.
    *
    *    Licensed 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
    *
    *       https://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.ibatis.datasource.pooled;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.locks.ReentrantLock;
  
  /**
   * @author Clinton Begin
   */
  public class PoolState {
  
    // This lock does not guarantee consistency.
    // Field values can be modified in PooledDataSource
    // after the instance is returned from
    // PooledDataSource#getPoolState().
    // A possible fix is to create and return a 'snapshot'.
    private final ReentrantLock lock = new ReentrantLock();
  
    protected PooledDataSource dataSource;
  
    protected final List<PooledConnection> idleConnections = new ArrayList<>();
    protected final List<PooledConnection> activeConnections = new ArrayList<>();
    protected long requestCount;
    protected long accumulatedRequestTime;
    protected long accumulatedCheckoutTime;
    protected long claimedOverdueConnectionCount;
    protected long accumulatedCheckoutTimeOfOverdueConnections;
    protected long accumulatedWaitTime;
    protected long hadToWaitCount;
    protected long badConnectionCount;
  
    public PoolState(PooledDataSource dataSource) {
      this.dataSource = dataSource;
    }
  
    public long getRequestCount() {
      lock.lock();
      try {
        return requestCount;
      } finally {
        lock.unlock();
      }
    }
  
    public long getAverageRequestTime() {
      lock.lock();
      try {
        return requestCount == 0 ? 0 : accumulatedRequestTime / requestCount;
      } finally {
        lock.unlock();
      }
    }
  
    public long getAverageWaitTime() {
      lock.lock();
      try {
        return hadToWaitCount == 0 ? 0 : accumulatedWaitTime / hadToWaitCount;
      } finally {
        lock.unlock();
      }
    }
  
    public long getHadToWaitCount() {
      lock.lock();
      try {
        return hadToWaitCount;
      } finally {
        lock.unlock();
      }
    }
  
    public long getBadConnectionCount() {
      lock.lock();
      try {
        return badConnectionCount;
      } finally {
        lock.unlock();
      }
    }
  
    public long getClaimedOverdueConnectionCount() {
      lock.lock();
      try {
        return claimedOverdueConnectionCount;
     } finally {
       lock.unlock();
     }
   }
 
   public long getAverageOverdueCheckoutTime() {
     lock.lock();
     try {
       return claimedOverdueConnectionCount == 0 ? 0
           : accumulatedCheckoutTimeOfOverdueConnections / claimedOverdueConnectionCount;
     } finally {
       lock.unlock();
     }
   }
 
   public long getAverageCheckoutTime() {
     lock.lock();
     try {
       return requestCount == 0 ? 0 : accumulatedCheckoutTime / requestCount;
     } finally {
       lock.unlock();
     }
   }
 
   public int getIdleConnectionCount() {
     lock.lock();
     try {
       return idleConnections.size();
     } finally {
       lock.unlock();
     }
   }
 
   public int getActiveConnectionCount() {
     lock.lock();
     try {
       return activeConnections.size();
     } finally {
       lock.unlock();
     }
   }
 
   @Override
   public String toString() {
     lock.lock();
     try {
       StringBuilder builder = new StringBuilder();
       builder.append("\n===CONFIGURATION==============================================");
       builder.append("\n jdbcDriver                     ").append(dataSource.getDriver());
       builder.append("\n jdbcUrl                        ").append(dataSource.getUrl());
       builder.append("\n jdbcUsername                   ").append(dataSource.getUsername());
       builder.append("\n jdbcPassword                   ")
           .append(dataSource.getPassword() == null ? "NULL" : "************");
       builder.append("\n poolMaxActiveConnections       ").append(dataSource.poolMaximumActiveConnections);
       builder.append("\n poolMaxIdleConnections         ").append(dataSource.poolMaximumIdleConnections);
       builder.append("\n poolMaxCheckoutTime            ").append(dataSource.poolMaximumCheckoutTime);
       builder.append("\n poolTimeToWait                 ").append(dataSource.poolTimeToWait);
       builder.append("\n poolPingEnabled                ").append(dataSource.poolPingEnabled);
       builder.append("\n poolPingQuery                  ").append(dataSource.poolPingQuery);
       builder.append("\n poolPingConnectionsNotUsedFor  ").append(dataSource.poolPingConnectionsNotUsedFor);
       builder.append("\n ---STATUS-----------------------------------------------------");
       builder.append("\n activeConnections              ").append(getActiveConnectionCount());
       builder.append("\n idleConnections                ").append(getIdleConnectionCount());
       builder.append("\n requestCount                   ").append(getRequestCount());
       builder.append("\n averageRequestTime             ").append(getAverageRequestTime());
       builder.append("\n averageCheckoutTime            ").append(getAverageCheckoutTime());
       builder.append("\n claimedOverdue                 ").append(getClaimedOverdueConnectionCount());
       builder.append("\n averageOverdueCheckoutTime     ").append(getAverageOverdueCheckoutTime());
       builder.append("\n hadToWait                      ").append(getHadToWaitCount());
       builder.append("\n averageWaitTime                ").append(getAverageWaitTime());
       builder.append("\n badConnectionCount             ").append(getBadConnectionCount());
       builder.append("\n===============================================================");
       return builder.toString();
     } finally {
       lock.unlock();
     }
   }
 
 }