/*
    * 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.bridge;
  
  import org.apache.log4j.Appender;
  import org.apache.log4j.Layout;
  import org.apache.log4j.helpers.AppenderAttachableImpl;
  import org.apache.log4j.spi.AppenderAttachable;
  import org.apache.log4j.spi.ErrorHandler;
  import org.apache.log4j.spi.Filter;
  import org.apache.log4j.spi.LoggingEvent;
  import org.apache.logging.log4j.Logger;
  import org.apache.logging.log4j.core.filter.AbstractFilterable;
  import org.apache.logging.log4j.status.StatusLogger;
  
  import java.util.ArrayList;
  import java.util.Enumeration;
  import java.util.List;
  
  /**
   * Holds a Log4j 2 Appender in an empty Log4j 1 Appender so it can be extracted when constructing the configuration.
   * Allows a Log4j 1 Appender to reference a Log4j 2 Appender.
   */
  public class AppenderWrapper extends AppenderAttachableImpl implements Appender {
  
      private static final Logger LOGGER = StatusLogger.getLogger();
      private final org.apache.logging.log4j.core.Appender appender;
  
      public AppenderWrapper(org.apache.logging.log4j.core.Appender appender) {
          this.appender = appender;
      }
  
      public org.apache.logging.log4j.core.Appender getAppender() {
          return appender;
      }
  
      @Override
      public void addFilter(Filter newFilter) {
          if (appender instanceof AbstractFilterable) {
              if (newFilter instanceof FilterWrapper) {
                  ((AbstractFilterable) appender).addFilter(((FilterWrapper) newFilter).getFilter());
              } else {
                  ((AbstractFilterable) appender).addFilter(new FilterAdapter(newFilter));
              }
          } else {
              LOGGER.warn("Unable to add filter to appender {}, it does not support filters", appender.getName());
          }
      }
  
      @Override
      public Filter getFilter() {
          return null;
      }
  
      @Override
      public void clearFilters() {
  
      }
  
      @Override
      public void close() {
          // Not supported with Log4j 2.
      }
  
      @Override
      public void doAppend(LoggingEvent event) {
          if (event instanceof LogEventAdapter) {
              appender.append(((LogEventAdapter) event).getEvent());
          }
      }
  
      @Override
      public String getName() {
          return appender.getName();
      }
  
      @Override
      public void setErrorHandler(ErrorHandler errorHandler) {
          appender.setHandler(new ErrorHandlerAdapter(errorHandler));
      }
  
      @Override
      public ErrorHandler getErrorHandler() {
          return ((ErrorHandlerAdapter)appender.getHandler()).getHandler();
      }
 
     @Override
     public void setLayout(Layout layout) {
         // Log4j 2 doesn't support this.
     }
 
     @Override
     public Layout getLayout() {
         return new LayoutWrapper(appender.getLayout());
     }
 
     @Override
     public void setName(String name) {
         // Log4j 2 doesn't support this.
     }
 
     @Override
     public boolean requiresLayout() {
         return false;
     }
 }