/*
    * 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.builders.appender;
  
  import org.apache.log4j.Appender;
  import org.apache.log4j.bridge.AppenderWrapper;
  import org.apache.log4j.bridge.RewritePolicyAdapter;
  import org.apache.log4j.bridge.RewritePolicyWrapper;
  import org.apache.log4j.builders.AbstractBuilder;
  import org.apache.log4j.builders.Holder;
  import org.apache.log4j.config.Log4j1Configuration;
  import org.apache.log4j.config.PropertiesConfiguration;
  import org.apache.log4j.helpers.OptionConverter;
  import org.apache.log4j.rewrite.RewritePolicy;
  import org.apache.log4j.spi.Filter;
  import org.apache.log4j.xml.XmlConfiguration;
  import org.apache.logging.log4j.Logger;
  import org.apache.logging.log4j.core.appender.rewrite.RewriteAppender;
  import org.apache.logging.log4j.core.config.AppenderRef;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.status.StatusLogger;
  import org.w3c.dom.Element;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Properties;
  
  import static org.apache.log4j.builders.BuilderManager.CATEGORY;
  import static org.apache.log4j.config.Log4j1Configuration.APPENDER_REF_TAG;
  import static org.apache.log4j.config.Log4j1Configuration.THRESHOLD_PARAM;
  import static org.apache.log4j.xml.XmlConfiguration.FILTER_TAG;
  import static org.apache.log4j.xml.XmlConfiguration.NAME_ATTR;
  import static org.apache.log4j.xml.XmlConfiguration.PARAM_TAG;
  import static org.apache.log4j.xml.XmlConfiguration.VALUE_ATTR;
  import static org.apache.log4j.xml.XmlConfiguration.forEachElement;
  
  
  /**
   * Build an Asynch Appender
   */
  @Plugin(name = "org.apache.log4j.rewrite.RewriteAppender", category = CATEGORY)
  public class RewriteAppenderBuilder extends AbstractBuilder implements AppenderBuilder {
  
      private static final Logger LOGGER = StatusLogger.getLogger();
      private static final String REWRITE_POLICY_TAG = "rewritePolicy";
  
      public RewriteAppenderBuilder() {
      }
  
      public RewriteAppenderBuilder(String prefix, Properties props) {
          super(prefix, props);
      }
  
      @Override
      public Appender parseAppender(final Element appenderElement, final XmlConfiguration config) {
          String name = appenderElement.getAttribute(NAME_ATTR);
          Holder<List<String>> appenderRefs = new Holder<>(new ArrayList<>());
          Holder<RewritePolicy> rewritePolicyHolder = new Holder<>();
          Holder<String> level = new Holder<>();
          Holder<Filter> filter = new Holder<>();
          forEachElement(appenderElement.getChildNodes(), (currentElement) -> {
              switch (currentElement.getTagName()) {
                  case APPENDER_REF_TAG:
                      Appender appender = config.findAppenderByReference(currentElement);
                      if (appender != null) {
                          appenderRefs.get().add(appender.getName());
                      }
                      break;
                  case REWRITE_POLICY_TAG: {
                      RewritePolicy policy = config.parseRewritePolicy(currentElement);
                      if (policy != null) {
                          rewritePolicyHolder.set(policy);
                      }
                      break;
                  }
                  case FILTER_TAG: {
                      filter.set(config.parseFilters(currentElement));
                      break;
                  }
                  case PARAM_TAG: {
                      if (currentElement.getAttribute(NAME_ATTR).equalsIgnoreCase(THRESHOLD_PARAM)) {
                          String value = currentElement.getAttribute(VALUE_ATTR);
                          if (value == null) {
                              LOGGER.warn("No value supplied for Threshold parameter, ignoring.");
                          } else {
                             level.set(value);
                         }
                     }
                     break;
                 }
             }
         });
         return createAppender(name, level.get(), appenderRefs.get().toArray(new String[0]), rewritePolicyHolder.get(),
                 filter.get(), config);
     }
 
     @Override
     public Appender parseAppender(final String name, final String appenderPrefix, final String layoutPrefix,
             final String filterPrefix, final Properties props, final PropertiesConfiguration configuration) {
         String appenderRef = getProperty(APPENDER_REF_TAG);
         Filter filter = configuration.parseAppenderFilters(props, filterPrefix, name);
         String policyPrefix = appenderPrefix + ".rewritePolicy";
         String className = getProperty(policyPrefix);
         RewritePolicy policy = configuration.getBuilderManager().parseRewritePolicy(className, policyPrefix,
                 props, configuration);
         String level = getProperty(THRESHOLD_PARAM);
         if (appenderRef == null) {
             LOGGER.warn("No appender references configured for AsyncAppender {}", name);
             return null;
         }
         Appender appender = configuration.parseAppender(props, appenderRef);
         if (appender == null) {
             LOGGER.warn("Cannot locate Appender {}", appenderRef);
             return null;
         }
         return createAppender(name, level, new String[] {appenderRef}, policy, filter, configuration);
     }
 
     private <T extends Log4j1Configuration> Appender createAppender(String name, String level,
             String[] appenderRefs, RewritePolicy policy, Filter filter, T configuration) {
         org.apache.logging.log4j.Level logLevel = OptionConverter.convertLevel(level,
                 org.apache.logging.log4j.Level.TRACE);
         AppenderRef[] refs = new AppenderRef[appenderRefs.length];
         int index = 0;
         for (String appenderRef : appenderRefs) {
             refs[index++] = AppenderRef.createAppenderRef(appenderRef, logLevel, null);
         }
         org.apache.logging.log4j.core.Filter rewriteFilter = buildFilters(level, filter);
         org.apache.logging.log4j.core.appender.rewrite.RewritePolicy rewritePolicy;
         if (policy instanceof RewritePolicyWrapper) {
             rewritePolicy = ((RewritePolicyWrapper) policy).getPolicy();
         } else {
             rewritePolicy = new RewritePolicyAdapter(policy);
         }
         return new AppenderWrapper(RewriteAppender.createAppender(name, "true", refs, configuration,
                 rewritePolicy, rewriteFilter));
     }
 }