/*
    * 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.filter;
  
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Objects;
  
  import org.apache.logging.log4j.Level;
  import org.apache.logging.log4j.Marker;
  import org.apache.logging.log4j.ThreadContext;
  import org.apache.logging.log4j.core.Filter;
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.Logger;
  import org.apache.logging.log4j.core.config.Node;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
  import org.apache.logging.log4j.core.config.plugins.PluginElement;
  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
  import org.apache.logging.log4j.core.util.KeyValuePair;
  import org.apache.logging.log4j.message.Message;
  
  /**
   * Compare against a log level that is associated with an MDC value.
   */
  @Plugin(name = "DynamicThresholdFilter", category = Node.CATEGORY, elementType = Filter.ELEMENT_TYPE, printObject = true)
  public final class DynamicThresholdFilter extends AbstractFilter {
  
      private static final long serialVersionUID = 1L;
  
      /**
       * Create the DynamicThresholdFilter.
       * @param key The name of the key to compare.
       * @param pairs An array of value and Level pairs.
       * @param defaultThreshold The default Level.
       * @param onMatch The action to perform if a match occurs.
       * @param onMismatch The action to perform if no match occurs.
       * @return The DynamicThresholdFilter.
       */
      @PluginFactory
      public static DynamicThresholdFilter createFilter(
              @PluginAttribute("key") final String key,
              @PluginElement("Pairs") final KeyValuePair[] pairs,
              @PluginAttribute("defaultThreshold") final Level defaultThreshold,
              @PluginAttribute("onMatch") final Result onMatch,
              @PluginAttribute("onMismatch") final Result onMismatch) {
          final Map<String, Level> map = new HashMap<>();
          for (final KeyValuePair pair : pairs) {
              map.put(pair.getKey(), Level.toLevel(pair.getValue()));
          }
          final Level level = defaultThreshold == null ? Level.ERROR : defaultThreshold;
          return new DynamicThresholdFilter(key, map, level, onMatch, onMismatch);
      }
      private Level defaultThreshold = Level.ERROR;
      private final String key;
  
      private Map<String, Level> levelMap = new HashMap<>();
  
      private DynamicThresholdFilter(final String key, final Map<String, Level> pairs, final Level defaultLevel,
                                     final Result onMatch, final Result onMismatch) {
          super(onMatch, onMismatch);
          Objects.requireNonNull(key, "key cannot be null");
          this.key = key;
          this.levelMap = pairs;
          this.defaultThreshold = defaultLevel;
      }
  
      @Override
      public boolean equals(final Object obj) {
          if (this == obj) {
              return true;
          }
          if (!super.equalsImpl(obj)) {
              return false;
          }
          if (getClass() != obj.getClass()) {
              return false;
          }
          final DynamicThresholdFilter other = (DynamicThresholdFilter) obj;
          if (defaultThreshold == null) {
              if (other.defaultThreshold != null) {
                  return false;
              }
          } else if (!defaultThreshold.equals(other.defaultThreshold)) {
              return false;
         }
         if (key == null) {
             if (other.key != null) {
                 return false;
             }
         } else if (!key.equals(other.key)) {
             return false;
         }
         if (levelMap == null) {
             if (other.levelMap != null) {
                 return false;
             }
         } else if (!levelMap.equals(other.levelMap)) {
             return false;
         }
         return true;
     }
 
     private Result filter(final Level level) {
         final Object value = ThreadContext.get(key);
         if (value != null) {
             Level ctxLevel = levelMap.get(value);
             if (ctxLevel == null) {
                 ctxLevel = defaultThreshold;
             }
             return level.isMoreSpecificThan(ctxLevel) ? onMatch : onMismatch;
         }
         return Result.NEUTRAL;
 
     }
 
     @Override
     public Result filter(final LogEvent event) {
         return filter(event.getLevel());
     }
 
     @Override
     public Result filter(final Logger logger, final Level level, final Marker marker, final Message msg,
                          final Throwable t) {
         return filter(level);
     }
 
     @Override
     public Result filter(final Logger logger, final Level level, final Marker marker, final Object msg,
                          final Throwable t) {
         return filter(level);
     }
 
     @Override
     public Result filter(final Logger logger, final Level level, final Marker marker, final String msg,
                          final Object... params) {
         return filter(level);
     }
 
     public String getKey() {
         return this.key;
     }
 
     public Map<String, Level> getLevelMap() {
         return levelMap;
     }
 
     @Override
     public int hashCode() {
         final int prime = 31;
         int result = super.hashCodeImpl();
         result = prime * result + ((defaultThreshold == null) ? 0 : defaultThreshold.hashCode());
         result = prime * result + ((key == null) ? 0 : key.hashCode());
         result = prime * result + ((levelMap == null) ? 0 : levelMap.hashCode());
         return result;
     }
 
     @Override
     public String toString() {
         final StringBuilder sb = new StringBuilder();
         sb.append("key=").append(key);
         sb.append(", default=").append(defaultThreshold);
         if (levelMap.size() > 0) {
             sb.append('{');
             boolean first = true;
             for (final Map.Entry<String, Level> entry : levelMap.entrySet()) {
                 if (!first) {
                     sb.append(", ");
                     first = false;
                 }
                 sb.append(entry.getKey()).append('=').append(entry.getValue());
             }
             sb.append('}');
         }
         return sb.toString();
     }
 }