/*
    * 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.config;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.TimeUnit;
  import java.util.concurrent.atomic.AtomicBoolean;
  import java.util.concurrent.atomic.AtomicInteger;
  import java.util.concurrent.locks.Condition;
  import java.util.concurrent.locks.Lock;
  import java.util.concurrent.locks.ReentrantLock;
  
  import org.apache.logging.log4j.Level;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Marker;
  import org.apache.logging.log4j.core.Appender;
  import org.apache.logging.log4j.core.Filter;
  import org.apache.logging.log4j.core.LogEvent;
  import org.apache.logging.log4j.core.async.AsyncLoggerContextSelector;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
  import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
  import org.apache.logging.log4j.core.config.plugins.PluginElement;
  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
  import org.apache.logging.log4j.core.filter.AbstractFilterable;
  import org.apache.logging.log4j.core.impl.DefaultLogEventFactory;
  import org.apache.logging.log4j.core.impl.LogEventFactory;
  import org.apache.logging.log4j.core.lookup.StrSubstitutor;
  import org.apache.logging.log4j.core.util.Booleans;
  import org.apache.logging.log4j.core.util.Constants;
  import org.apache.logging.log4j.core.util.Loader;
  import org.apache.logging.log4j.message.Message;
  import org.apache.logging.log4j.util.PropertiesUtil;
  import org.apache.logging.log4j.util.Strings;
  
  /**
   * Logger object that is created via configuration.
   */
  @Plugin(name = "logger", category = "Core", printObject = true)
  public class LoggerConfig extends AbstractFilterable {
  
      private static final int MAX_RETRIES = 3;
      private static LogEventFactory LOG_EVENT_FACTORY = null;
  
      private List<AppenderRef> appenderRefs = new ArrayList<AppenderRef>();
      private final Map<String, AppenderControl> appenders = new ConcurrentHashMap<String, AppenderControl>();
      private final String name;
      private LogEventFactory logEventFactory;
      private Level level;
      private boolean additive = true;
      private boolean includeLocation = true;
      private LoggerConfig parent;
      private final AtomicInteger counter = new AtomicInteger();
      private final AtomicBoolean shutdown = new AtomicBoolean(false);
      private final Map<Property, Boolean> properties;
      private final Configuration config;
      private final Lock shutdownLock = new ReentrantLock();
      private final Condition noLogEvents = shutdownLock.newCondition(); // should only be used when shutdown == true
  
      static {
          final String factory = PropertiesUtil.getProperties().getStringProperty(Constants.LOG4J_LOG_EVENT_FACTORY);
          if (factory != null) {
              try {
                  final Class<?> clazz = Loader.loadClass(factory);
                  if (clazz != null && LogEventFactory.class.isAssignableFrom(clazz)) {
                      LOG_EVENT_FACTORY = (LogEventFactory) clazz.newInstance();
                  }
              } catch (final Exception ex) {
                  LOGGER.error("Unable to create LogEventFactory {}", factory, ex);
              }
          }
          if (LOG_EVENT_FACTORY == null) {
              LOG_EVENT_FACTORY = new DefaultLogEventFactory();
          }
      }
  
      /**
      * Default constructor.
      */
     public LoggerConfig() {
         this.logEventFactory = LOG_EVENT_FACTORY;
         this.level = Level.ERROR;
         this.name = Strings.EMPTY;
         this.properties = null;
         this.config = null;
     }
 
     /**
      * Constructor that sets the name, level and additive values.
      *
      * @param name The Logger name.
      * @param level The Level.
      * @param additive true if the Logger is additive, false otherwise.
      */
     public LoggerConfig(final String name, final Level level,
             final boolean additive) {
         this.logEventFactory = LOG_EVENT_FACTORY;
         this.name = name;
         this.level = level;
         this.additive = additive;
         this.properties = null;
         this.config = null;
     }
 
     protected LoggerConfig(final String name,
             final List<AppenderRef> appenders, final Filter filter,
             final Level level, final boolean additive,
             final Property[] properties, final Configuration config,
             final boolean includeLocation) {
         super(filter);
         this.logEventFactory = LOG_EVENT_FACTORY;
         this.name = name;
         this.appenderRefs = appenders;
         this.level = level;
         this.additive = additive;
         this.includeLocation = includeLocation;
         this.config = config;
         if (properties != null && properties.length > 0) {
             this.properties = new HashMap<Property, Boolean>(properties.length);
             for (final Property prop : properties) {
                 final boolean interpolate = prop.getValue().contains("${");
                 this.properties.put(prop, interpolate);
             }
         } else {
             this.properties = null;
         }
     }
 
     @Override
     public Filter getFilter() {
         return super.getFilter();
     }
 
     /**
      * Returns the name of the LoggerConfig.
      *
      * @return the name of the LoggerConfig.
      */
     public String getName() {
         return name;
     }
 
     /**
      * Sets the parent of this LoggerConfig.
      *
      * @param parent the parent LoggerConfig.
      */
     public void setParent(final LoggerConfig parent) {
         this.parent = parent;
     }
 
     /**
      * Returns the parent of this LoggerConfig.
      *
      * @return the LoggerConfig that is the parent of this one.
      */
     public LoggerConfig getParent() {
         return this.parent;
     }
 
     /**
      * Adds an Appender to the LoggerConfig.
      *
      * @param appender The Appender to add.
      * @param level The Level to use.
      * @param filter A Filter for the Appender reference.
      */
     public void addAppender(final Appender appender, final Level level,
             final Filter filter) {
         appenders.put(appender.getName(), new AppenderControl(appender, level,
                 filter));
     }
 
     /**
      * Removes the Appender with the specific name.
      *
      * @param name The name of the Appender.
      */
     public void removeAppender(final String name) {
         final AppenderControl ctl = appenders.remove(name);
         if (ctl != null) {
             cleanupFilter(ctl);
         }
     }
 
     /**
      * Returns all Appenders as a Map.
      *
      * @return a Map with the Appender name as the key and the Appender as the
      *         value.
      */
     public Map<String, Appender> getAppenders() {
         final Map<String, Appender> map = new HashMap<String, Appender>();
         for (final Map.Entry<String, AppenderControl> entry : appenders
                 .entrySet()) {
             map.put(entry.getKey(), entry.getValue().getAppender());
         }
         return map;
     }
 
     /**
      * Removes all Appenders.
      */
     protected void clearAppenders() {
         waitForCompletion();
         final Collection<AppenderControl> controls = appenders.values();
         final Iterator<AppenderControl> iterator = controls.iterator();
         while (iterator.hasNext()) {
             final AppenderControl ctl = iterator.next();
             iterator.remove();
             cleanupFilter(ctl);
         }
     }
 
     private void cleanupFilter(final AppenderControl ctl) {
         final Filter filter = ctl.getFilter();
         if (filter != null) {
             ctl.removeFilter(filter);
             filter.stop();
         }
     }
 
     /**
      * Returns the Appender references.
      *
      * @return a List of all the Appender names attached to this LoggerConfig.
      */
     public List<AppenderRef> getAppenderRefs() {
         return appenderRefs;
     }
 
     /**
      * Sets the logging Level.
      *
      * @param level The logging Level.
      */
     public void setLevel(final Level level) {
         this.level = level;
     }
 
     /**
      * Returns the logging Level.
      *
      * @return the logging Level.
      */
     public Level getLevel() {
         return level == null ? parent.getLevel() : level;
     }
 
     /**
      * Returns the LogEventFactory.
      *
      * @return the LogEventFactory.
      */
     public LogEventFactory getLogEventFactory() {
         return logEventFactory;
     }
 
     /**
      * Sets the LogEventFactory. Usually the LogEventFactory will be this
      * LoggerConfig.
      *
      * @param logEventFactory the LogEventFactory.
      */
     public void setLogEventFactory(final LogEventFactory logEventFactory) {
         this.logEventFactory = logEventFactory;
     }
 
     /**
      * Returns the valid of the additive flag.
      *
      * @return true if the LoggerConfig is additive, false otherwise.
      */
     public boolean isAdditive() {
         return additive;
     }
 
     /**
      * Sets the additive setting.
      *
      * @param additive true if the LoggerConfig should be additive, false
      *            otherwise.
      */
     public void setAdditive(final boolean additive) {
         this.additive = additive;
     }
 
     /**
      * Returns the value of logger configuration attribute {@code includeLocation},
      * or, if no such attribute was configured, {@code true} if logging is
      * synchronous or {@code false} if logging is asynchronous.
      *
      * @return whether location should be passed downstream
      */
     public boolean isIncludeLocation() {
         return includeLocation;
     }
 
     /**
      * Returns an unmodifiable map with the configuration properties, or
      * {@code null} if this {@code LoggerConfig} does not have any configuration
      * properties.
      * <p>
      * For each {@code Property} key in the map, the value is {@code true} if
      * the property value has a variable that needs to be substituted.
      *
      * @return an unmodifiable map with the configuration properties, or
      *         {@code null}
      * @see Configuration#getStrSubstitutor()
      * @see StrSubstitutor
      */
     // LOG4J2-157
     public Map<Property, Boolean> getProperties() {
         return properties == null ? null : Collections
                 .unmodifiableMap(properties);
     }
 
     /**
      * Logs an event.
      *
      * @param loggerName The name of the Logger.
      * @param fqcn The fully qualified class name of the caller.
      * @param marker A Marker or null if none is present.
      * @param level The event Level.
      * @param data The Message.
      * @param t A Throwable or null.
      */
     public void log(final String loggerName, final String fqcn,
             final Marker marker, final Level level, final Message data,
             final Throwable t) {
         List<Property> props = null;
         if (properties != null) {
             props = new ArrayList<Property>(properties.size());
 
             for (final Map.Entry<Property, Boolean> entry : properties.entrySet()) {
                 final Property prop = entry.getKey();
                 final String value = entry.getValue() ? config.getStrSubstitutor()
                         .replace(prop.getValue()) : prop.getValue();
                 props.add(Property.createProperty(prop.getName(), value));
             }
         }
         final LogEvent event = logEventFactory.createEvent(loggerName, marker, fqcn, level, data, props, t);
         log(event);
     }
 
     /**
      * Waits for all log events to complete before shutting down this
      * loggerConfig.
      */
     private void waitForCompletion() {
         shutdownLock.lock();
         try {
             if (shutdown.compareAndSet(false, true)) {
                 int retries = 0;
                 while (counter.get() > 0) {
                     try {
                         noLogEvents.await(retries + 1, TimeUnit.SECONDS);
                     } catch (final InterruptedException ie) {
                         if (++retries > MAX_RETRIES) {
                             break;
                         }
                     }
                 }
             }
         } finally {
             shutdownLock.unlock();
         }
     }
 
     /**
      * Logs an event.
      *
      * @param event The log event.
      */
     public void log(final LogEvent event) {
 
         counter.incrementAndGet();
         try {
             if (isFiltered(event)) {
                 return;
             }
 
             event.setIncludeLocation(isIncludeLocation());
 
             callAppenders(event);
 
             if (additive && parent != null) {
                 parent.log(event);
             }
         } finally {
             if (counter.decrementAndGet() == 0) {
                 shutdownLock.lock();
                 try {
                     if (shutdown.get()) {
                         noLogEvents.signalAll();
                     }
                 } finally {
                     shutdownLock.unlock();
                 }
             }
         }
     }
 
     protected void callAppenders(final LogEvent event) {
         for (final AppenderControl control : appenders.values()) {
             control.callAppender(event);
         }
     }
 
 
     @Override
     public String toString() {
         return Strings.isEmpty(name) ? "root" : name;
     }
 
     /**
      * Factory method to create a LoggerConfig.
      *
      * @param additivity True if additive, false otherwise.
      * @param level The Level to be associated with the Logger.
      * @param loggerName The name of the Logger.
      * @param includeLocation whether location should be passed downstream
      * @param refs An array of Appender names.
      * @param properties Properties to pass to the Logger.
      * @param config The Configuration.
      * @param filter A Filter.
      * @return A new LoggerConfig.
      */
     @PluginFactory
     public static LoggerConfig createLogger(
             @PluginAttribute("additivity") final String additivity,
             @PluginAttribute("level") final Level level,
             @PluginAttribute("name") final String loggerName,
             @PluginAttribute("includeLocation") final String includeLocation,
             @PluginElement("AppenderRef") final AppenderRef[] refs,
             @PluginElement("Properties") final Property[] properties,
             @PluginConfiguration final Configuration config,
             @PluginElement("Filter") final Filter filter) {
         if (loggerName == null) {
             LOGGER.error("Loggers cannot be configured without a name");
             return null;
         }
 
         final List<AppenderRef> appenderRefs = Arrays.asList(refs);
         final String name = loggerName.equals("root") ? Strings.EMPTY : loggerName;
         final boolean additive = Booleans.parseBoolean(additivity, true);
 
         return new LoggerConfig(name, appenderRefs, filter, level, additive,
                 properties, config, includeLocation(includeLocation));
     }
 
     // Note: for asynchronous loggers, includeLocation default is FALSE,
     // for synchronous loggers, includeLocation default is TRUE.
     protected static boolean includeLocation(final String includeLocationConfigValue) {
         if (includeLocationConfigValue == null) {
             final boolean sync = !AsyncLoggerContextSelector.class.getName()
                     .equals(System.getProperty(Constants.LOG4J_CONTEXT_SELECTOR));
             return sync;
         }
         return Boolean.parseBoolean(includeLocationConfigValue);
     }
 
     /**
      * The root Logger.
      */
     @Plugin(name = "root", category = "Core", printObject = true)
     public static class RootLogger extends LoggerConfig {
 
         @PluginFactory
         public static LoggerConfig createLogger(
                 @PluginAttribute("additivity") final String additivity,
                 @PluginAttribute("level") final Level level,
                 @PluginAttribute("includeLocation") final String includeLocation,
                 @PluginElement("AppenderRef") final AppenderRef[] refs,
                 @PluginElement("Properties") final Property[] properties,
                 @PluginConfiguration final Configuration config,
                 @PluginElement("Filter") final Filter filter) {
             final List<AppenderRef> appenderRefs = Arrays.asList(refs);
             final Level actualLevel = level == null ? Level.ERROR : level;
             final boolean additive = Booleans.parseBoolean(additivity, true);
 
             return new LoggerConfig(LogManager.ROOT_LOGGER_NAME, appenderRefs,
                     filter, actualLevel, additive, properties, config,
                     includeLocation(includeLocation));
         }
     }
 
 }