/*
    * 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.slf4j;
  
  import java.util.Map;
  import java.util.Map.Entry;
  
  import org.apache.logging.log4j.spi.CleanableThreadContextMap;
  import org.apache.logging.log4j.util.SortedArrayStringMap;
  import org.apache.logging.log4j.util.StringMap;
  import org.slf4j.MDC;
  
  /**
   * Bind the ThreadContextMap to the SLF4J MDC.
   */
  public class MDCContextMap implements CleanableThreadContextMap {
  
      private static final StringMap EMPTY_CONTEXT_DATA = new SortedArrayStringMap(1);
      static {
          EMPTY_CONTEXT_DATA.freeze();
      }
  
      @Override
      public void put(final String key, final String value) {
          MDC.put(key, value);
      }
  
      @Override
      public void putAll(final Map<String, String> m) {
          for (final Entry<String, String> entry : m.entrySet()) {
              MDC.put(entry.getKey(), entry.getValue());
          }
      }
  
      @Override
      public String get(final String key) {
          return MDC.get(key);
      }
  
      @Override
      public void remove(final String key) {
          MDC.remove(key);
      }
  
  
      @Override
      public void removeAll(final Iterable<String> keys) {
          for (final String key : keys) {
              MDC.remove(key);
          }
      }
  
      @Override
      public void clear() {
          MDC.clear();
      }
  
      @Override
      public boolean containsKey(final String key) {
          return MDC.getCopyOfContextMap().containsKey(key);
      }
  
      @Override
      @SuppressWarnings("unchecked") // nothing we can do about this, restricted by SLF4J API
      public Map<String, String> getCopy() {
          return MDC.getCopyOfContextMap();
      }
  
      @Override
      @SuppressWarnings("unchecked") // nothing we can do about this, restricted by SLF4J API
      public Map<String, String> getImmutableMapOrNull() {
          return MDC.getCopyOfContextMap();
      }
  
      @Override
      public boolean isEmpty() {
          return MDC.getCopyOfContextMap().isEmpty();
      }
  
      @Override
      public StringMap getReadOnlyContextData() {
          final Map<String, String> copy = getCopy();
          if (copy.isEmpty()) {
              return EMPTY_CONTEXT_DATA;
          }
         final StringMap result = new SortedArrayStringMap();
         for (final Entry<String, String> entry : copy.entrySet()) {
             result.putValue(entry.getKey(), entry.getValue());
         }
         return result;
     }
 }