/*
 * Copyright 2001-2004 The Apache Software Foundation.
 * 
 * Licensed 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.commons.logging.impl;


import java.io.Serializable;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.logging.LogRecord;
import java.util.StringTokenizer;
import java.io.PrintWriter;
import java.io.StringWriter;

import org.apache.commons.logging.Log;


/**
 * 
Implementation of the org.apache.commons.logging.Log
 * interface that wraps the standard JDK logging mechanisms that are
 * available in SourceForge's Lumberjack for JDKs prior to 1.4.
 *
 * @author Scott Sanders
 * @author Berin Loritsch
 * @author Peter Donald
 * @author Vince Eagen
 * @version $Revision: 1.6 $ $Date: 2004/06/06 21:13:43 $
 */

public class Jdk13LumberjackLogger implements Log, Serializable {


    // ----------------------------------------------------- Instance Variables


    /**
     * The underlying Logger implementation we are using.
     */
    protected transient Logger logger = null;
    protected String name = null;
    private String sourceClassName = "unknown";
    private String sourceMethodName = "unknown";
    private boolean classAndMethodFound = false;


    // ----------------------------------------------------------- Constructors


    /**
     * Construct a named instance of this Logger.
     *
     * @param name Name of the logger to be constructed
     */
    public Jdk13LumberjackLogger(String name) {

        this.name = name;
        logger = getLogger();

    }


    // --------------------------------------------------------- Public Methods


    private void log( Level level, String msg, Throwable ex ) {
        if( getLogger().isLoggable(level) ) {
            LogRecord record = new LogRecord(level, msg);
            if( !classAndMethodFound ) {
                getClassAndMethod();
            }
            record.setSourceClassName(sourceClassName);
            record.setSourceMethodName(sourceMethodName);
            if( ex != null ) {
                record.setThrown(ex);
            }
            getLogger().log(record);
        }
    }

    /**
     * 
Gets the class and method by looking at the stack trace for the
     * first entry that is not this class.
     */
    private void getClassAndMethod() {
        try {
            Throwable throwable = new Throwable();
            throwable.fillInStackTrace();
            StringWriter stringWriter = new StringWriter();
            PrintWriter printWriter = new PrintWriter( stringWriter );
            throwable.printStackTrace( printWriter );
            String traceString = stringWriter.getBuffer().toString();
            StringTokenizer tokenizer =
                new StringTokenizer( traceString, "\n" );
            tokenizer.nextToken();
            String line = tokenizer.nextToken();
            while ( line.indexOf( this.getClass().getName() )  == -1 ) {
                line = tokenizer.nextToken();
            }
            while ( line.indexOf( this.getClass().getName() ) >= 0 ) {
                line = tokenizer.nextToken();
            }
            int start = line.indexOf( "at " ) + 3;
            int end = line.indexOf( '(' );
            String temp = line.substring( start, end );
            int lastPeriod = temp.lastIndexOf( '.' );
            sourceClassName = temp.substring( 0, lastPeriod );
            sourceMethodName = temp.substring( lastPeriod + 1 );
        } catch ( Exception ex ) {
            // ignore - leave class and methodname unknown
        }
        classAndMethodFound = true;
    }

    /**
     * Log a message with debug log level.
     */
    public void debug(Object message) {
        log(Level.FINE, String.valueOf(message), null);
    }


    /**
     * Log a message and exception with debug log level.
     */
    public void debug(Object message, Throwable exception) {
        log(Level.FINE, String.valueOf(message), exception);
    }


    /**
     * Log a message with error log level.
     */
    public void error(Object message) {
        log(Level.SEVERE, String.valueOf(message), null);
    }


    /**
     * Log a message and exception with error log level.
     */
    public void error(Object message, Throwable exception) {
        log(Level.SEVERE, String.valueOf(message), exception);
    }


    /**
     * Log a message with fatal log level.
     */
    public void fatal(Object message) {
        log(Level.SEVERE, String.valueOf(message), null);
    }


    /**
     * Log a message and exception with fatal log level.
     */
    public void fatal(Object message, Throwable exception) {
        log(Level.SEVERE, String.valueOf(message), exception);
    }


    /**
     * Return the native Logger instance we are using.
     */
    public Logger getLogger() {
        if (logger == null) {
            logger = Logger.getLogger(name);
        }
        return (logger);
    }


    /**
     * Log a message with info log level.
     */
    public void info(Object message) {
        log(Level.INFO, String.valueOf(message), null);
    }


    /**
     * Log a message and exception with info log level.
     */
    public void info(Object message, Throwable exception) {
        log(Level.INFO, String.valueOf(message), exception);
    }


    /**
     * Is debug logging currently enabled?
     */
    public boolean isDebugEnabled() {
        return (getLogger().isLoggable(Level.FINE));
    }


    /**
     * Is error logging currently enabled?
     */
    public boolean isErrorEnabled() {
        return (getLogger().isLoggable(Level.SEVERE));
    }


    /**
     * Is fatal logging currently enabled?
     */
    public boolean isFatalEnabled() {
        return (getLogger().isLoggable(Level.SEVERE));
    }


    /**
     * Is info logging currently enabled?
     */
    public boolean isInfoEnabled() {
        return (getLogger().isLoggable(Level.INFO));
    }


    /**
     * Is trace logging currently enabled?
     */
    public boolean isTraceEnabled() {
        return (getLogger().isLoggable(Level.FINEST));
    }


    /**
     * Is warn logging currently enabled?
     */
    public boolean isWarnEnabled() {
        return (getLogger().isLoggable(Level.WARNING));
    }


    /**
     * Log a message with trace log level.
     */
    public void trace(Object message) {
        log(Level.FINEST, String.valueOf(message), null);
    }


    /**
     * Log a message and exception with trace log level.
     */
    public void trace(Object message, Throwable exception) {
        log(Level.FINEST, String.valueOf(message), exception);
    }


    /**
     * Log a message with warn log level.
     */
    public void warn(Object message) {
        log(Level.WARNING, String.valueOf(message), null);
    }


    /**
     * Log a message and exception with warn log level.
     */
    public void warn(Object message, Throwable exception) {
        log(Level.WARNING, String.valueOf(message), exception);
    }


}