/*
    * 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.log4j.rewrite;
  
  import org.apache.log4j.bridge.LogEventAdapter;
  import org.apache.log4j.helpers.OptionConverter;
  import org.apache.log4j.spi.LocationInfo;
  import org.apache.log4j.spi.LoggingEvent;
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.impl.Log4jLogEvent;
  import org.apache.logging.log4j.message.MapMessage;
  import org.apache.logging.log4j.message.Message;
  import org.apache.logging.log4j.message.SimpleMessage;
  import org.apache.logging.log4j.util.SortedArrayStringMap;
  
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * This policy rewrites events where the message of the
   * original event implements java.util.Map.
   * All other events are passed through unmodified.
   * If the map contains a "message" entry, the value will be
   * used as the message for the rewritten event.  The rewritten
   * event will have a property set that is the combination of the
   * original property set and the other members of the message map.
   * If both the original property set and the message map
   * contain the same entry, the value from the message map
   * will overwrite the original property set.
   * <p>
   * The combination of the RewriteAppender and this policy
   * performs the same actions as the MapFilter from log4j 1.3.
   * </p>
   */
  public class MapRewritePolicy implements RewritePolicy {
      /**
       * {@inheritDoc}
       */
      @Override
      public LoggingEvent rewrite(final LoggingEvent source) {
          Object msg = source.getMessage();
          if (msg instanceof MapMessage || msg instanceof Map) {
              Map<String, String> props = source.getProperties() != null ? new HashMap<>(source.getProperties())
                      : new HashMap<>();
              @SuppressWarnings("unchecked")
              Map<String, Object> eventProps = msg instanceof Map ? (Map) msg : ((MapMessage) msg).getData();
              //
              //   if the map sent in the logging request
              //      has "message" entry, use that as the message body
              //      otherwise, use the entire map.
              //
              Message newMessage = null;
              Object newMsg = eventProps.get("message");
              if (newMsg != null) {
                  newMessage = new SimpleMessage(newMsg.toString());
                  for (Map.Entry<String, Object> entry : eventProps.entrySet()) {
                      if (!("message".equals(entry.getKey()))) {
                          props.put(entry.getKey(), entry.getValue().toString());
                      }
                  }
              } else {
                  return source;
              }
  
              LogEvent event;
              if (source instanceof LogEventAdapter) {
                  event = new Log4jLogEvent.Builder(((LogEventAdapter) source).getEvent())
                          .setMessage(newMessage)
                          .setContextData(new SortedArrayStringMap(props))
                          .build();
              } else {
                  LocationInfo info = source.getLocationInformation();
                  StackTraceElement element = new StackTraceElement(info.getClassName(), info.getMethodName(),
                          info.getFileName(), Integer.parseInt(info.getLineNumber()));
                  Thread thread = getThread(source.getThreadName());
                  long threadId = thread != null ? thread.getId() : 0;
                  int threadPriority = thread != null ? thread.getPriority() : 0;
                  event = Log4jLogEvent.newBuilder()
                          .setContextData(new SortedArrayStringMap(props))
                          .setLevel(OptionConverter.convertLevel(source.getLevel()))
                          .setLoggerFqcn(source.getFQNOfLoggerClass())
                          .setMarker(null)
                          .setMessage(newMessage)
                          .setSource(element)
                          .setLoggerName(source.getLoggerName())
                         .setThreadName(source.getThreadName())
                         .setThreadId(threadId)
                         .setThreadPriority(threadPriority)
                         .setThrown(source.getThrowableInformation().getThrowable())
                         .setTimeMillis(source.getTimeStamp())
                         .setNanoTime(0)
                         .setThrownProxy(null)
                         .build();
             }
             return new LogEventAdapter(event);
         }
         return source;
 
     }
 
     private Thread getThread(String name) {
         for (Thread thread : Thread.getAllStackTraces().keySet()) {
             if (thread.getName().equals(name)) {
                 return thread;
             }
         }
         return null;
     }
 }