/*
 *
 * MariaDB Client for Java
 *
 * Copyright (c) 2012-2014 Monty Program Ab.
 * Copyright (c) 2015-2020 MariaDB Corporation Ab.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along
 * with this library; if not, write to Monty Program Ab info@montyprogram.com.
 *
 * This particular MariaDB Client for Java file is work
 * derived from a Drizzle-JDBC. Drizzle-JDBC file which is covered by subject to
 * the following copyright and notice provisions:
 *
 * Copyright (c) 2009-2011, Marcus Eriksson
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this list
 * of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice, this
 * list of conditions and the following disclaimer in the documentation and/or
 * other materials provided with the distribution.
 *
 * Neither the name of the driver nor the names of its contributors may not be
 * used to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS  AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 */

package org.mariadb.jdbc;

import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicLong;
import javax.sql.*;

public class MariaDbPooledConnection implements PooledConnection {

  private final MariaDbConnection connection;
  private final List<ConnectionEventListener> connectionEventListeners;
  private final List<StatementEventListener> statementEventListeners;
  private final AtomicLong lastUsed;

  /**
   * Constructor.
   *
   * @param connection connection to retrieve connection options
   */
  public MariaDbPooledConnection(MariaDbConnection connection) {
    this.connection = connection;
    connection.pooledConnection = this;
    statementEventListeners = new CopyOnWriteArrayList<>();
    connectionEventListeners = new CopyOnWriteArrayList<>();
    lastUsed = new AtomicLong(System.nanoTime());
  }

  /**
   * Creates and returns a <code>Connection</code> object that is a handle for the physical
   * connection that this <code>PooledConnection</code> object represents. The connection pool
   * manager calls this method when an application has called the method <code>
   * DataSource.getConnection</code> and there are no <code>PooledConnection</code> objects
   * available. See the {@link PooledConnection interface description} for more information.
   *
   * @return a <code>Connection</code> object that is a handle to this <code>PooledConnection</code>
   *     object
   */
  public MariaDbConnection getConnection() {
    return connection;
  }

  /**
   * Closes the physical connection that this <code>PooledConnection</code> object represents. An
   * application never calls this method directly; it is called by the connection pool module, or
   * manager. <br>
   * See the {@link PooledConnection interface description} for more information.
   *
   * @throws SQLException if a database access error occurs
   */
  public void close() throws SQLException {
    connection.pooledConnection = null;
    connection.close();
  }

  /**
   * Abort connection.
   *
   * @param executor executor
   * @throws SQLException if a database access error occurs
   */
  public void abort(Executor executor) throws SQLException {
    connection.pooledConnection = null;
    connection.abort(executor);
  }

  /**
   * Registers the given event failover so that it will be notified when an event occurs on this
   * <code>PooledConnection</code> object.
   *
   * @param listener a component, usually the connection pool manager, that has implemented the
   *     <code>ConnectionEventListener</code> interface and wants to be notified when the connection
   *     is closed or has an error
   * @see #removeConnectionEventListener
   */
  public void addConnectionEventListener(ConnectionEventListener listener) {
    connectionEventListeners.add(listener);
  }

  /**
   * Removes the given event failover from the list of components that will be notified when an
   * event occurs on this <code>PooledConnection</code> object.
   *
   * @param listener a component, usually the connection pool manager, that has implemented the
   *     <code>ConnectionEventListener</code> interface and been registered with this <code>
   *     PooledConnection</code> object as a failover
   * @see #addConnectionEventListener
   */
  public void removeConnectionEventListener(ConnectionEventListener listener) {
    connectionEventListeners.remove(listener);
  }

  /**
   * Registers a <code>StatementEventListener</code> with this <code>PooledConnection</code> object.
   * Components that wish to be notified when <code>PreparedStatement</code>s created by the
   * connection are closed or are detected to be invalid may use this method to register a <code>
   * StatementEventListener</code> with this <code>PooledConnection</code> object. <br>
   *
   * @param listener an component which implements the <code>StatementEventListener</code> interface
   *     that is to be registered with this <code>PooledConnection</code> object <br>
   */
  public void addStatementEventListener(StatementEventListener listener) {
    statementEventListeners.add(listener);
  }

  /**
   * Removes the specified <code>StatementEventListener</code> from the list of components that will
   * be notified when the driver detects that a <code>PreparedStatement</code> has been closed or is
   * invalid. <br>
   *
   * @param listener the component which implements the <code>StatementEventListener</code>
   *     interface that was previously registered with this <code>PooledConnection</code> object
   *     <br>
   */
  public void removeStatementEventListener(StatementEventListener listener) {
    statementEventListeners.remove(listener);
  }

  /**
   * Fire statement close event to listeners.
   *
   * @param st statement
   */
  public void fireStatementClosed(Statement st) {
    if (st instanceof PreparedStatement) {
      StatementEvent event = new StatementEvent(this, (PreparedStatement) st);
      for (StatementEventListener listener : statementEventListeners) {
        listener.statementClosed(event);
      }
    }
  }

  /**
   * Fire statement error to listeners.
   *
   * @param st statement
   * @param ex exception
   */
  public void fireStatementErrorOccurred(Statement st, SQLException ex) {
    if (st instanceof PreparedStatement) {
      StatementEvent event = new StatementEvent(this, (PreparedStatement) st, ex);
      for (StatementEventListener listener : statementEventListeners) {
        listener.statementErrorOccurred(event);
      }
    }
  }

  /** Fire Connection close to listening listeners. */
  public void fireConnectionClosed() {
    ConnectionEvent event = new ConnectionEvent(this);
    for (ConnectionEventListener listener : connectionEventListeners) {
      listener.connectionClosed(event);
    }
  }

  /**
   * Fire connection error to listening listeners.
   *
   * @param ex exception
   */
  public void fireConnectionErrorOccurred(SQLException ex) {
    ConnectionEvent event = new ConnectionEvent(this, ex);
    for (ConnectionEventListener listener : connectionEventListeners) {
      listener.connectionErrorOccurred(event);
    }
  }

  /**
   * Indicate if there are any registered listener.
   *
   * @return true if no listener.
   */
  public boolean noStmtEventListeners() {
    return statementEventListeners.isEmpty();
  }

  /**
   * Indicate last time this pool connection has been used.
   *
   * @return current last used time (nano).
   */
  public AtomicLong getLastUsed() {
    return lastUsed;
  }

  /** Set last poolConnection use to now. */
  public void lastUsedToNow() {
    lastUsed.set(System.nanoTime());
  }

  public void ensureValidation() {
    lastUsed.set(0);
  }
}
