/*
    * 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.pattern;
  
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.core.impl.ThrowableProxy;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Scanner;
  
  /**
   * Outputs the Throwable portion of the LoggingEvent as a full stacktrace
   * unless this converter's option is 'short', where it just outputs the first line of the trace, or if
   * the number of lines to print is explicitly specified.
   * <p>
   * The extended stack trace will also include the location of where the class was loaded from and the
   * version of the jar if available.
   */
  @Plugin(name = "ExtendedThrowablePatternConverter", type = "Converter")
  @ConverterKeys({"xEx", "xThrowable", "xException" })
  public final class ExtendedThrowablePatternConverter extends ThrowablePatternConverter {
  
      private static final String FILTERS = "filters(";
  
      private final List<String> packages;
  
      /**
       * Private constructor.
       *
       * @param options options, may be null.
       */
      private ExtendedThrowablePatternConverter(final String[] options) {        
          super("ExtendedThrowable", "throwable", options);
          List<String> tempPackages = null;
          if (options != null && options.length > 1) {
              if (options[1].startsWith(FILTERS) && options[1].endsWith(")")) {
                  String filterStr = options[1].substring(FILTERS.length(), options[1].length() - 1);
                  String[] array = filterStr.split(",");
                  if (array.length > 0) {
                      tempPackages = new ArrayList<String>(array.length);
                      for (String token : array) {
                          tempPackages.add(token.trim());
                      }
                  }
              }
          }
          packages = tempPackages;
      }
  
      /**
       * Gets an instance of the class.
       *
       * @param options pattern options, may be null.  If first element is "short",
       *                only the first line of the throwable will be formatted.
       * @return instance of class.
       */
      public static ExtendedThrowablePatternConverter newInstance(final String[] options) {
          String type = null;
          String[] array = options;
          if (options != null && options.length == 1 && options[0].length() > 0) {
              String[] opts = options[0].split(",", 2);
              String first = opts[0].trim();
              String filter;
              Scanner scanner = new Scanner(first);
              if (first.equalsIgnoreCase(FULL) || first.equalsIgnoreCase(SHORT) || scanner.hasNextInt()) {
                  type = first;
                  filter = opts[1].trim();
              } else {
                  filter = options[0].trim();
              }
              array = new String[] {type, filter};
          }
  
          return new ExtendedThrowablePatternConverter(array);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public void format(final LogEvent event, final StringBuilder toAppendTo) {
          Throwable throwable = event.getThrown();
          if (throwable != null) {
             if (!(throwable instanceof ThrowableProxy)) {
                 super.format(event, toAppendTo);
                 return;
             }
             ThrowableProxy t = (ThrowableProxy) throwable;
             String trace = t.getExtendedStackTrace(packages);
             int len = toAppendTo.length();
             if (len > 0 && !Character.isWhitespace(toAppendTo.charAt(len - 1))) {
                 toAppendTo.append(" ");
             }
             if (lines > 0) {
                 StringBuilder sb = new StringBuilder();
                 String[] array = trace.split("\n");
                 for (int i = 0; i < lines; ++i) {
                     sb.append(array[i]).append("\n");
                 }
                 toAppendTo.append(sb.toString());
 
             } else {
                 toAppendTo.append(trace);
             }
         }
     }
 }