/*
    * 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.impl;
  
  import java.io.InvalidObjectException;
  import java.io.ObjectInputStream;
  import java.io.Serializable;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.logging.log4j.Level;
  import org.apache.logging.log4j.Marker;
  import org.apache.logging.log4j.ThreadContext;
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.config.Property;
  import org.apache.logging.log4j.message.LoggerNameAwareMessage;
  import org.apache.logging.log4j.message.Message;
  import org.apache.logging.log4j.message.TimestampMessage;
  
  /**
   * Implementation of a LogEvent.
   */
  public class Log4jLogEvent implements LogEvent {
  
      private static final long serialVersionUID = -1351367343806656055L;
      private static final String NOT_AVAIL = "?";
      private final String fqcnOfLogger;
      private final Marker marker;
      private final Level level;
      private final String name;
      private final Message message;
      private final long timestamp;
      private final ThrowableProxy throwable;
      private final Map<String, String> mdc;
      private final ThreadContext.ContextStack ndc;
      private String threadName = null;
      private StackTraceElement location;
      private boolean includeLocation;
      private boolean endOfBatch = false;
  
      /**
       *
       */
      public Log4jLogEvent(final long timestamp) {
          this("", null, "", null, null, (ThrowableProxy) null, null, null, null, null, timestamp);
      }
  
      /**
       * Constructor.
       * @param loggerName The name of the Logger.
       * @param marker The Marker or null.
       * @param fqcn The fully qualified class name of the caller.
       * @param level The logging Level.
       * @param message The Message.
       * @param t A Throwable or null.
       */
      public Log4jLogEvent(final String loggerName, final Marker marker, final String fqcn, final Level level,
                           final Message message, final Throwable t) {
          this(loggerName, marker, fqcn, level, message, null, t);
      }
  
      /**
       * Constructor.
       * @param loggerName The name of the Logger.
       * @param marker The Marker or null.
       * @param fqcn The fully qualified class name of the caller.
       * @param level The logging Level.
       * @param message The Message.
       * @param properties properties to add to the event.
       * @param t A Throwable or null.
       */
      public Log4jLogEvent(final String loggerName, final Marker marker, final String fqcn, final Level level,
                           final Message message, final List<Property> properties, final Throwable t) {
          this(loggerName, marker, fqcn, level, message, t,
              createMap(properties),
              ThreadContext.getDepth() == 0 ? null : ThreadContext.cloneStack(), null,
              null, System.currentTimeMillis());
      }
  
      /**
       * Constructor.
       * @param loggerName The name of the Logger.
       * @param marker The Marker or null.
      * @param fqcn The fully qualified class name of the caller.
      * @param level The logging Level.
      * @param message The Message.
      * @param t A Throwable or null.
      * @param mdc The mapped diagnostic context.
      * @param ndc the nested diagnostic context.
      * @param threadName The name of the thread.
      * @param location The locations of the caller.
      * @param timestamp The timestamp of the event.
      */
     public Log4jLogEvent(final String loggerName, final Marker marker, final String fqcn, final Level level,
                          final Message message, final Throwable t,
                          final Map<String, String> mdc, final ThreadContext.ContextStack ndc, final String threadName,
                          final StackTraceElement location, final long timestamp) {
         this(loggerName, marker, fqcn, level, message, t == null ? null : new ThrowableProxy(t), mdc, ndc, threadName,
             location, timestamp);
     }
 
     /**
      * Create a new LogEvent.
      * @param loggerName The name of the Logger.
      * @param marker The Marker or null.
      * @param fqcn The fully qualified class name of the caller.
      * @param level The logging Level.
      * @param message The Message.
      * @param t A ThrowableProxy or null.
      * @param mdc The mapped diagnostic context.
      * @param ndc the nested diagnostic context.
      * @param threadName The name of the thread.
      * @param location The locations of the caller.
      * @param timestamp The timestamp of the event.
      */
     public static Log4jLogEvent createEvent(final String loggerName, final Marker marker, final String fqcn,
                                             final Level level, final Message message, final ThrowableProxy t,
                                             final Map<String, String> mdc, final ThreadContext.ContextStack ndc,
                                             final String threadName, final StackTraceElement location,
                                             final long timestamp) {
      return new Log4jLogEvent(loggerName, marker, fqcn, level, message, t, mdc, ndc, threadName, location, timestamp);
     }
 
     /**
      * Constructor.
      * @param loggerName The name of the Logger.
      * @param marker The Marker or null.
      * @param fqcn The fully qualified class name of the caller.
      * @param level The logging Level.
      * @param message The Message.
      * @param t A ThrowableProxy or null.
      * @param mdc The mapped diagnostic context.
      * @param ndc the nested diagnostic context.
      * @param threadName The name of the thread.
      * @param location The locations of the caller.
      * @param timestamp The timestamp of the event.
      */
     private Log4jLogEvent(final String loggerName, final Marker marker, final String fqcn, final Level level,
                          final Message message, final ThrowableProxy t,
                          final Map<String, String> mdc, final ThreadContext.ContextStack ndc, final String threadName,
                          final StackTraceElement location, final long timestamp) {
         name = loggerName;
         this.marker = marker;
         this.fqcnOfLogger = fqcn;
         this.level = level;
         this.message = message;
         this.throwable = t;
         this.mdc = mdc;
         this.ndc = ndc;
         this.timestamp = message instanceof TimestampMessage ? ((TimestampMessage) message).getTimestamp() : timestamp;
         this.threadName = threadName;
         this.location = location;
         if (message != null && message instanceof LoggerNameAwareMessage) {
             ((LoggerNameAwareMessage) message).setLoggerName(name);
         }
     }
 
     private static Map<String, String> createMap(final List<Property> properties) {
         final Map<String, String> contextMap = ThreadContext.getImmutableContext();
         if (contextMap == null && (properties == null || properties.size() == 0)) {
             return null;
         }
         if (properties == null || properties.size() == 0) {
             return contextMap; // contextMap is not null
         }
         final Map<String, String> map = new HashMap<String, String>(contextMap);
 
         for (final Property prop : properties) {
             if (!map.containsKey(prop.getName())) {
                 map.put(prop.getName(), prop.getValue());
             }
         }
         return Collections.unmodifiableMap(map);
     }
 
     /**
      * Returns the logging Level.
      * @return the Level associated with this event.
      */
     @Override
     public Level getLevel() {
         return level;
     }
 
     /**
      * Returns the name of the Logger used to generate the event.
      * @return The Logger name.
      */
     @Override
     public String getLoggerName() {
         return name;
     }
 
     /**
      * Returns the Message associated with the event.
      * @return The Message.
      */
     @Override
     public Message getMessage() {
         return message;
     }
 
     /**
      * Returns the name of the Thread on which the event was generated.
      * @return The name of the Thread.
      */
     @Override
     public String getThreadName() {
         if (threadName == null) {
             threadName = Thread.currentThread().getName();
         }
         return threadName;
     }
 
     /**
      * Returns the time in milliseconds from the epoch when the event occurred.
      * @return The time the event occurred.
      */
     @Override
     public long getMillis() {
         return timestamp;
     }
 
     /**
      * Returns the Throwable associated with the event, or null.
      * @return The Throwable associated with the event.
      */
     @Override
     public Throwable getThrown() {
         return throwable == null ? null : throwable.getThrowable();
     }
 
     /**
      * Returns the ThrowableProxy associated with the event, or null.
      * @return The ThrowableProxy associated with the event.
      */
     public ThrowableProxy getThrownProxy() {
         return throwable;
     }
 
 
     /**
      * Returns the Marker associated with the event, or null.
      * @return the Marker associated with the event.
      */
     @Override
     public Marker getMarker() {
         return marker;
     }
 
     /**
      * The fully qualified class name of the class that was called by the caller.
      * @return the fully qualified class name of the class that is performing logging.
      */
     @Override
     public String getFQCN() {
         return fqcnOfLogger;
     }
 
     /**
      * Returns the immutable copy of the ThreadContext Map.
      * @return The context Map.
      */
     @Override
     public Map<String, String> getContextMap() {
         return mdc == null ? ThreadContext.EMPTY_MAP : mdc;
     }
 
     /**
      * Returns an immutable copy of the ThreadContext stack.
      * @return The context Stack.
      */
     @Override
     public ThreadContext.ContextStack getContextStack() {
         return ndc == null ? ThreadContext.EMPTY_STACK : ndc;
     }
 
     /**
      * Returns the StackTraceElement for the caller. This will be the entry that occurs right
      * before the first occurrence of FQCN as a class name.
      * @return the StackTraceElement for the caller.
      */
     @Override
     public StackTraceElement getSource() {
         if (location != null) {
             return location;
         }
         if (fqcnOfLogger == null || !includeLocation) {
             return null;
         }
         location = calcLocation(fqcnOfLogger);
         return location;
     }
 
     public static StackTraceElement calcLocation(final String fqcnOfLogger) {
         if (fqcnOfLogger == null) {
             return null;
         }
         final StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
         boolean next = false;
         for (final StackTraceElement element : stackTrace) {
             final String className = element.getClassName();
             if (next) {
                 if (fqcnOfLogger.equals(className)) {
                     continue;
                 }
                 return element;
             }
 
             if (fqcnOfLogger.equals(className)) {
                 next = true;
             } else if (NOT_AVAIL.equals(className)) {
                 break;
             }
         }
         return null;
     }
 
     @Override
     public boolean isIncludeLocation() {
         return includeLocation;
     }
 
     @Override
     public void setIncludeLocation(final boolean includeLocation) {
         this.includeLocation = includeLocation;
     }
 
     @Override
     public boolean isEndOfBatch() {
         return endOfBatch;
     }
 
     @Override
     public void setEndOfBatch(final boolean endOfBatch) {
         this.endOfBatch = endOfBatch;
     }
 
     /**
      * Creates a LogEventProxy that can be serialized.
      * @return a LogEventProxy.
      */
     protected Object writeReplace() {
         return new LogEventProxy(this, this.includeLocation);
     }
 
     public static Serializable serialize(final Log4jLogEvent event,
             final boolean includeLocation) {
         return new LogEventProxy(event, includeLocation);
     }
 
     public static Log4jLogEvent deserialize(final Serializable event) {
         if (event == null) {
             throw new NullPointerException("Event cannot be null");
         }
         if (event instanceof LogEventProxy) {
             final LogEventProxy proxy = (LogEventProxy) event;
             final Log4jLogEvent result = new Log4jLogEvent(proxy.name, proxy.marker,
                     proxy.fqcnOfLogger, proxy.level, proxy.message,
                     proxy.throwable, proxy.mdc, proxy.ndc, proxy.threadName,
                     proxy.location, proxy.timestamp);
             result.setEndOfBatch(proxy.isEndOfBatch);
             result.setIncludeLocation(proxy.isLocationRequired);
             return result;
         }
         throw new IllegalArgumentException("Event is not a serialized LogEvent: " + event.toString());
     }
 
     private void readObject(final ObjectInputStream stream) throws InvalidObjectException {
         throw new InvalidObjectException("Proxy required");
     }
 
     @Override
     public String toString() {
         final StringBuilder sb = new StringBuilder();
         final String n = name.isEmpty() ? "root" : name;
         sb.append("Logger=").append(n);
         sb.append(" Level=").append(level.name());
         sb.append(" Message=").append(message.getFormattedMessage());
         return sb.toString();
     }
 
     /**
      * Proxy pattern used to serialize the LogEvent.
      */
     private static class LogEventProxy implements Serializable {
 
         private static final long serialVersionUID = -7139032940312647146L;
         private final String fqcnOfLogger;
         private final Marker marker;
         private final Level level;
         private final String name;
         private final Message message;
         private final long timestamp;
         private final ThrowableProxy throwable;
         private final Map<String, String> mdc;
         private final ThreadContext.ContextStack ndc;
         private final String threadName;
         private final StackTraceElement location;
         private final boolean isLocationRequired;
         private final boolean isEndOfBatch;
 
         public LogEventProxy(final Log4jLogEvent event, final boolean includeLocation) {
             this.fqcnOfLogger = event.fqcnOfLogger;
             this.marker = event.marker;
             this.level = event.level;
             this.name = event.name;
             this.message = event.message;
             this.timestamp = event.timestamp;
             this.throwable = event.throwable;
             this.mdc = event.mdc;
             this.ndc = event.ndc;
             this.location = includeLocation ? event.getSource() : null;
             this.threadName = event.getThreadName();
             this.isLocationRequired = includeLocation;
             this.isEndOfBatch = event.endOfBatch;
         }
 
         /**
          * Returns a Log4jLogEvent using the data in the proxy.
          * @return Log4jLogEvent.
          */
         protected Object readResolve() {
             final Log4jLogEvent result = new Log4jLogEvent(name, marker, fqcnOfLogger,
                     level, message, throwable, mdc, ndc, threadName, location,
                     timestamp);
             result.setEndOfBatch(isEndOfBatch);
             result.setIncludeLocation(isLocationRequired);
             return result;
         }
     }
 }