/*
    * 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;
  
  import java.io.Serializable;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.apache.logging.log4j.core.Filter;
  import org.apache.logging.log4j.core.Layout;
  import org.apache.logging.log4j.core.config.Configuration;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.core.config.plugins.PluginAliases;
  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.layout.SerializedLayout;
  import org.apache.logging.log4j.core.net.AbstractSocketManager;
  import org.apache.logging.log4j.core.net.Advertiser;
  import org.apache.logging.log4j.core.net.DatagramSocketManager;
  import org.apache.logging.log4j.core.net.Protocol;
  import org.apache.logging.log4j.core.net.SslSocketManager;
  import org.apache.logging.log4j.core.net.TcpSocketManager;
  import org.apache.logging.log4j.core.net.ssl.SslConfiguration;
  import org.apache.logging.log4j.core.util.Booleans;
  import org.apache.logging.log4j.util.EnglishEnums;
  
  /**
   * An Appender that delivers events over socket connections. Supports both TCP and UDP.
   */
  @Plugin(name = "Socket", category = "Core", elementType = "appender", printObject = true)
  public class SocketAppender extends AbstractOutputStreamAppender<AbstractSocketManager> {
  
      private static final long serialVersionUID = 1L;
  
      private Object advertisement;
      private final Advertiser advertiser;
  
      protected SocketAppender(final String name, final Layout<? extends Serializable> layout, final Filter filter,
              final AbstractSocketManager manager, final boolean ignoreExceptions, final boolean immediateFlush,
              final Advertiser advertiser) {
          super(name, layout, filter, ignoreExceptions, immediateFlush, manager);
          if (advertiser != null) {
              final Map<String, String> configuration = new HashMap<>(layout.getContentFormat());
              configuration.putAll(manager.getContentFormat());
              configuration.put("contentType", layout.getContentType());
              configuration.put("name", name);
              this.advertisement = advertiser.advertise(configuration);
          }
          this.advertiser = advertiser;
      }
  
      @Override
      public void stop() {
          super.stop();
          if (this.advertiser != null) {
              this.advertiser.unadvertise(this.advertisement);
          }
      }
  
      /**
       * 
       * @param host
       *        The name of the host to connect to.
       * @param portNum
       *        The port to connect to on the target host.
       * @param protocolStr
       *        The Protocol to use.
       * @param sslConfig
       *        The SSL configuration file for TCP/SSL, ignored for UPD.
       * @param connectTimeoutMillis
       *        the connect timeout in milliseconds.
       * @param delayMillis
       *        The interval in which failed writes should be retried.
       * @param immediateFail
       *        True if the write should fail if no socket is immediately available.
       * @param name
       *        The name of the Appender.
       * @param immediateFlush
       *        "true" if data should be flushed on each write.
       * @param ignore
       *        If {@code "true"} (default) exceptions encountered when appending events are logged; otherwise they are
       *        propagated to the caller.
       * @param layout
      *        The layout to use (defaults to SerializedLayout).
      * @param filter
      *        The Filter or null.
      * @param advertise
      *        "true" if the appender configuration should be advertised, "false" otherwise.
      * @param config
      *        The Configuration
      * @return A SocketAppender.
      */
     @PluginFactory
     public static SocketAppender createAppender(
             // @formatter:off
             @PluginAttribute("host") final String host,
             @PluginAttribute("port") final String portNum,
             @PluginAttribute("protocol") final String protocolStr,
             @PluginElement("SSL") final SslConfiguration sslConfig,
             @PluginAttribute(value = "connectTimeoutMillis", defaultInt = 0) final int connectTimeoutMillis,
             @PluginAliases("reconnectionDelay") // deprecated
             @PluginAttribute("reconnectionDelayMillis") final String delayMillis,
             @PluginAttribute("immediateFail") final String immediateFail,
             @PluginAttribute("name") final String name,
             @PluginAttribute("immediateFlush") final String immediateFlush,
             @PluginAttribute("ignoreExceptions") final String ignore,
             @PluginElement("Layout") Layout<? extends Serializable> layout,
             @PluginElement("Filter") final Filter filter, 
             @PluginAttribute("advertise") final String advertise, @PluginConfiguration final Configuration config) {
             // @formatter:on
         boolean isFlush = Booleans.parseBoolean(immediateFlush, true);
         final boolean isAdvertise = Boolean.parseBoolean(advertise);
         final boolean ignoreExceptions = Booleans.parseBoolean(ignore, true);
         final boolean fail = Booleans.parseBoolean(immediateFail, true);
         final int reconnectDelayMillis = AbstractAppender.parseInt(delayMillis, 0);
         final int port = AbstractAppender.parseInt(portNum, 0);
         if (layout == null) {
             layout = SerializedLayout.createLayout();
         }
 
         if (name == null) {
             LOGGER.error("No name provided for SocketAppender");
             return null;
         }
 
         final Protocol protocol = EnglishEnums.valueOf(Protocol.class,
                 protocolStr != null ? protocolStr : Protocol.TCP.name());
         if (protocol == Protocol.UDP) {
             isFlush = true;
         }
 
         final AbstractSocketManager manager = createSocketManager(name, protocol, host, port, connectTimeoutMillis,
                 sslConfig, reconnectDelayMillis, fail, layout);
 
         return new SocketAppender(name, layout, filter, manager, ignoreExceptions, isFlush,
                 isAdvertise ? config.getAdvertiser() : null);
     }
 
     /**
      * Creates an AbstractSocketManager for TCP, UDP, and SSL.
      * 
      * @throws IllegalArgumentException
      *         if the protocol cannot be handled.
      */
     protected static AbstractSocketManager createSocketManager(final String name, Protocol protocol, final String host,
             final int port, final int connectTimeoutMillis, final SslConfiguration sslConfig, final int delayMillis,
             final boolean immediateFail, final Layout<? extends Serializable> layout) {
         if (protocol == Protocol.TCP && sslConfig != null) {
             // Upgrade TCP to SSL if an SSL config is specified.
             protocol = Protocol.SSL;
         }
         if (protocol != Protocol.SSL && sslConfig != null) {
             LOGGER.info("Appender {} ignoring SSL configuration for {} protocol", name, protocol);
         }
         switch (protocol) {
         case TCP:
             return TcpSocketManager.getSocketManager(host, port, connectTimeoutMillis, delayMillis, immediateFail,
                     layout);
         case UDP:
             return DatagramSocketManager.getSocketManager(host, port, layout);
         case SSL:
             return SslSocketManager.getSocketManager(sslConfig, host, port, connectTimeoutMillis, delayMillis,
                     immediateFail, layout);
         default:
             throw new IllegalArgumentException(protocol.toString());
         }
     }
 }