/**
 * Logback: the reliable, generic, fast and flexible logging framework.
 * 
 * Copyright (C) 1999-2006, QOS.ch
 * 
 * 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.
 */

package ch.qos.logback.access.db;

import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Enumeration;

import ch.qos.logback.access.spi.AccessEvent;
import ch.qos.logback.core.db.DBAppenderBase;

/**
 * The DBAppender inserts access events into three database tables in a format
 * independent of the Java programming language. 
 * 
 * For more informations about this appender, please refer to the online manual at
 * http://logback.qos.ch/manual/appenders.html#AccessDBAppender
 * 
 * @author Ceki G&uuml;lc&uuml;
 * @author Ray DeCampo
 * @author S&eacute;bastien Pennec
 */
public class DBAppender extends DBAppenderBase {
  protected static final String insertSQL;
  protected final String insertHeaderSQL = "INSERT INTO  access_event_header (event_id, header_key, header_value) VALUES (?, ?, ?)";
  protected static final Method GET_GENERATED_KEYS_METHOD; 

  private boolean insertHeaders = false;
  
  static {
    StringBuffer sql = new StringBuffer();
    sql.append("INSERT INTO access_event (");
    sql.append("timestmp, ");
    sql.append("requestURI, ");
    sql.append("requestURL, ");
    sql.append("remoteHost, ");
    sql.append("remoteUser, ");
    sql.append("remoteAddr, ");
    sql.append("protocol, ");
    sql.append("method, ");
    sql.append("serverName, ");
    sql.append("postContent) ");
    sql.append(" VALUES (?, ?, ? ,?, ?, ?, ?, ?, ?, ?)");
    insertSQL = sql.toString();

    Method getGeneratedKeysMethod;
    try {
      getGeneratedKeysMethod = PreparedStatement.class.getMethod(
          "getGeneratedKeys", (Class[]) null);
    } catch (Exception ex) {
      getGeneratedKeysMethod = null;
    }
    GET_GENERATED_KEYS_METHOD = getGeneratedKeysMethod;
  }
  
  public DBAppender() {
  }

  @Override
  protected void subAppend(Object eventObject, Connection connection,
      PreparedStatement insertStatement) throws Throwable {
    AccessEvent event = (AccessEvent) eventObject;

    addAccessEvent(insertStatement, event);
    
    int updateCount = insertStatement.executeUpdate();
    if (updateCount != 1) {
      addWarn("Failed to insert access event");
    }
    
    if (insertHeaders) {
      int eventId = getEventId(insertStatement, connection);
      addRequestHeaders(event, connection, eventId);
    }
  }
  
  void addAccessEvent(PreparedStatement stmt, AccessEvent event)
      throws SQLException {
    stmt.setLong(1, event.getTimeStamp());
    stmt.setString(2, event.getRequestURI());
    stmt.setString(3, event.getRequestURL());
    stmt.setString(4, event.getRemoteHost());
    stmt.setString(5, event.getRemoteUser());
    stmt.setString(6, event.getRemoteAddr());
    stmt.setString(7, event.getProtocol());
    stmt.setString(8, event.getMethod());
    stmt.setString(9, event.getServerName());
    stmt.setString(10, event.getPostContent()); 
  }
  
  void addRequestHeaders(AccessEvent event,
      Connection connection, int eventId) throws SQLException {
    Enumeration names = event.getRequestHeaderNames();
    if (names.hasMoreElements()) {
      PreparedStatement insertHeaderStatement = connection
          .prepareStatement(insertHeaderSQL);

      
      while (names.hasMoreElements()) {
        String key = (String) names.nextElement();
        String value = (String) event.getRequestHeader(key);

        insertHeaderStatement.setInt(1, eventId);
        insertHeaderStatement.setString(2, key);
        insertHeaderStatement.setString(3, value);

        if (cnxSupportsBatchUpdates) {
          insertHeaderStatement.addBatch();
        } else {
          insertHeaderStatement.execute();
        }
      }

      if (cnxSupportsBatchUpdates) {
        insertHeaderStatement.executeBatch();
      }

      insertHeaderStatement.close();
      insertHeaderStatement = null;
    }
  }

  @Override
  protected Method getGeneratedKeysMethod() {
    return GET_GENERATED_KEYS_METHOD;
  }

  @Override
  protected String getInsertSQL() {
    return insertSQL;
  }
  
  public void setInsertHeaders(boolean insertHeaders) {
    this.insertHeaders = insertHeaders;
  }
}
