/*
    * 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.logging.log4j.core.lookup;
  
  import java.io.File;
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.net.URL;
  
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.config.ConfigurationSource;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.status.StatusLogger;
  
  /**
   * Lookup properties of Log4j
   */
  @Plugin(name = "log4j", category = StrLookup.CATEGORY)
  public class Log4jLookup extends AbstractConfigurationAwareLookup {
  
      public final static String KEY_CONFIG_LOCATION = "configLocation";
      public final static String KEY_CONFIG_PARENT_LOCATION = "configParentLocation";
  
      private static final org.apache.logging.log4j.Logger LOGGER = StatusLogger.getLogger();
  
      private static String asPath(final URI uri) {
          if (uri.getScheme() == null || uri.getScheme().equals("file")) {
              return uri.getPath();
          }
          return uri.toString();
      }
  
      private static URI getParent(final URI uri) throws URISyntaxException {
          final String s = uri.toString();
          final int offset = s.lastIndexOf('/');
          if (offset > -1) {
              return new URI(s.substring(0, offset));
          }
          return new URI("../");
      }
  
      @Override
      public String lookup(final LogEvent event, final String key) {
          if (configuration != null) {
              final ConfigurationSource configSrc = configuration.getConfigurationSource();
              final File file = configSrc.getFile();
              if (file != null) {
                  switch (key) {
                      case KEY_CONFIG_LOCATION:
                          return file.getAbsolutePath();
  
                      case KEY_CONFIG_PARENT_LOCATION:
                          return file.getParentFile().getAbsolutePath();
  
                      default:
                          return null;
                  }
              }
  
              final URL url = configSrc.getURL();
              if (url != null) {
                  try {
                      switch (key) {
                          case KEY_CONFIG_LOCATION:
                              return asPath(url.toURI());
  
                          case KEY_CONFIG_PARENT_LOCATION:
                              return asPath(getParent(url.toURI()));
  
                          default:
                              return null;
                      }
                  } catch (final URISyntaxException use) {
                      LOGGER.error(use);
                      return null;
                  }
              }
          }
  
          return null;
      }
  }