/*
    * 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.appender.db.jpa.converter;
  
  import javax.persistence.AttributeConverter;
  import javax.persistence.Converter;
  
  import org.apache.logging.log4j.util.Strings;
  
  /**
   * A JPA 2.1 attribute converter for {@link StackTraceElement}s in {@link org.apache.logging.log4j.core.LogEvent}s. This
   * converter is capable of converting both to and from {@link String}s.
   */
  @Converter(autoApply = false)
  public class StackTraceElementAttributeConverter implements AttributeConverter<StackTraceElement, String> {
      private static final int UNKNOWN_SOURCE = -1;
  
      private static final int NATIVE_METHOD = -2;
  
      @Override
      public String convertToDatabaseColumn(final StackTraceElement element) {
          if (element == null) {
              return null;
          }
  
          return element.toString();
      }
  
      @Override
      public StackTraceElement convertToEntityAttribute(final String s) {
          if (Strings.isEmpty(s)) {
              return null;
          }
  
          return StackTraceElementAttributeConverter.convertString(s);
      }
  
      static StackTraceElement convertString(final String s) {
          final int open = s.indexOf("(");
  
          final String classMethod = s.substring(0, open);
          final String className = classMethod.substring(0, classMethod.lastIndexOf("."));
          final String methodName = classMethod.substring(classMethod.lastIndexOf(".") + 1);
  
          final String parenthesisContents = s.substring(open + 1, s.indexOf(")"));
  
          String fileName = null;
          int lineNumber = UNKNOWN_SOURCE;
          if ("Native Method".equals(parenthesisContents)) {
              lineNumber = NATIVE_METHOD;
          } else if (!"Unknown Source".equals(parenthesisContents)) {
              final int colon = parenthesisContents.indexOf(":");
              if (colon > UNKNOWN_SOURCE) {
                  fileName = parenthesisContents.substring(0, colon);
                  try {
                      lineNumber = Integer.parseInt(parenthesisContents.substring(colon + 1));
                  } catch (final NumberFormatException ignore) {
                      // we don't care
                  }
              } else {
                  fileName = parenthesisContents.substring(0);
              }
          }
  
          return new StackTraceElement(className, methodName, fileName, lineNumber);
      }
  }