/*
    * 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 org.apache.logging.log4j.Level;
  import org.apache.logging.log4j.Marker;
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.Logger;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.core.config.plugins.PluginAttr;
  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
  import org.apache.logging.log4j.message.Message;
  
  import java.util.Locale;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  /**
   * This filter returns the onMatch result if the message matches the regular expression.
   *
   * The "useRawMsg" attribute can be used to indicate whether the regular expression should be
   * applied to the result of calling Message.getMessageFormat (true) or Message.getFormattedMessage()
   * (false). The default is false.
   *
   */
  @Plugin(name = "RegexFilter", type = "Core", elementType = "filter", printObject = true)
  public final class RegexFilter extends AbstractFilter {
  
      private final Pattern pattern;
      private final boolean useRawMessage;
  
      private RegexFilter(boolean raw, Pattern pattern, Result onMatch, Result onMismatch) {
          super(onMatch, onMismatch);
          this.pattern = pattern;
          this.useRawMessage = raw;
      }
  
      @Override
      public Result filter(Logger logger, Level level, Marker marker, String msg, Object[] params) {
          return filter(msg);
      }
  
      @Override
      public Result filter(Logger logger, Level level, Marker marker, Object msg, Throwable t) {
          return filter(msg.toString());
      }
  
      @Override
      public Result filter(Logger logger, Level level, Marker marker, Message msg, Throwable t) {
          String text = useRawMessage ? msg.getFormat() : msg.getFormattedMessage();
          return filter(text);
      }
  
      @Override
      public Result filter(LogEvent event) {
          String text = useRawMessage ? event.getMessage().getFormat() : event.getMessage().getFormattedMessage();
          return filter(text);
      }
  
      private Result filter(String msg) {
          if (msg == null) {
              return onMismatch;
          }
          Matcher m = pattern.matcher(msg);
          return m.matches() ? onMatch : onMismatch;
      }
  
      @Override
      public String toString() {
          StringBuilder sb = new StringBuilder();
          sb.append("useRaw=").append(useRawMessage);
          sb.append(", pattern=").append(pattern.toString());
          return sb.toString();
      }
  
      /**
       * Create a Filter that matches a regular expression.
       * @param regex The regular expression to match.
       * @param useRawMsg If true, the raw message will be used, otherwise the formatted message will be used.
       * @param match The action to perform when a match occurs.
       * @param mismatch The action to perform when a mismatch occurs.
       * @return The RegexFilter.
       */
      @PluginFactory
      public static RegexFilter createFilter(@PluginAttr("regex") String regex,
                                            @PluginAttr("useRawMsg") String useRawMsg,
                                             @PluginAttr("onMatch") String match,
                                             @PluginAttr("onMismatch") String mismatch) {
 
         if (regex == null) {
             LOGGER.error("A regular expression must be provided for RegexFilter");
             return null;
         }
         boolean raw = useRawMsg == null ? false : Boolean.parseBoolean(useRawMsg);
         Pattern pattern;
         try {
             pattern = Pattern.compile(regex);
         } catch (Exception ex) {
             LOGGER.error("RegexFilter caught exception compiling pattern: " + regex + " cause: " + ex.getMessage());
             return null;
         }
         Result onMatch = Result.toResult(match);
         Result onMismatch = Result.toResult(mismatch);
 
         return new RegexFilter(raw, pattern, onMatch, onMismatch);
     }
 
 }