/*
    * 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.myfaces.trinidad.logging;
  
  import java.util.logging.Level;
  import java.util.logging.LogRecord;
  
  /**
   * Private subclass of LogRecord to hide TrinidadLogger in the stack trace.
   */
  class TrinidadLogRecord extends LogRecord 
  {
    public TrinidadLogRecord(Level level, String msg)
    {
      super(level, (msg == null) ? "" : msg);
      _needToInferCaller = true;
    }
  
  
    @Override
    public String getSourceClassName()
    {
      if (_needToInferCaller)
        _inferCaller();
  
      return super.getSourceClassName();
    }
  
    @Override
    public void setSourceClassName(String sourceClassName)
    {
      _needToInferCaller = false;
      super.setSourceClassName(sourceClassName);
    }
  
    @Override
    public String getSourceMethodName()
    {
      if (_needToInferCaller)
        _inferCaller();
  
      return super.getSourceMethodName();
    }
  
    @Override
    public void setSourceMethodName(String sourceMethodName)
    {
      _needToInferCaller = false;
      super.setSourceMethodName(sourceMethodName);
    }
  
    // Private method to infer the caller's class and method names
    private void _inferCaller()
    {
      _needToInferCaller = false;
      // Get the stack trace.
      StackTraceElement stack[] = (new Throwable()).getStackTrace();
      // First, search back to a method in the Logger class.
      int i = 0;
  
      while (i < stack.length)
      {
        StackTraceElement frame = stack[i];
        String cname = frame.getClassName();
        if (cname.equals(_JDK_LOG_CLASS) ||
            cname.equals(_TRINIDAD_LOG_CLASS))
          break;
  
        i++;
      }
  
      // Now search for the first frame before the "Logger" class.
      while (i < stack.length)
      {
        StackTraceElement frame = stack[i];
        String cname = frame.getClassName();
  
        if (cname.equals(_JDK_LOG_CLASS) ||
            cname.equals(_TRINIDAD_LOG_CLASS))
        {
          i++;
          continue;
        }
 
       String mname = frame.getMethodName();
       if ("log".equals(mname) ||
           "_log".equals(mname))
       {
         i++;
         continue;
       }
 
       // We've found the relevant frame.
       setSourceClassName(cname);
       setSourceMethodName(mname);
       return;
 
     }
 
     // Forcibly set both to null, so the LogRecord superclass
     // doesn't try to detect them on its own
     setSourceClassName(null);
     setSourceMethodName(null);
   }
 
   transient private boolean _needToInferCaller;
 
 
   private static final String _JDK_LOG_CLASS = 
     "java.util.logging.Logger";
   
   private static final String _TRINIDAD_LOG_CLASS =
     "org.apache.myfaces.trinidad.logging.TrinidadLogger";
 
   private static final long serialVersionUID = 1L;
 }