content: /*
   * Copyright 2020-2023 the original author or authors.
   *
   * 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
   *
   *      https://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 com.jun.mqttx.broker.handler;
  
  import com.jun.mqttx.config.MqttxConfig;
  import com.jun.mqttx.entity.Session;
  import com.jun.mqttx.service.IPubRelMessageService;
  import com.jun.mqttx.service.IPublishMessageService;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.handler.codec.mqtt.*;
  
  /**
   * {@link MqttMessageType#PUBREC} 消息处理器
   *
   * @author Jun
   * @since 1.0.4
   */
  @Handler(type = MqttMessageType.PUBREC)
  public class PubRecHandler extends AbstractMqttSessionHandler {
  
      private final IPubRelMessageService pubRelMessageService;
      private final IPublishMessageService publishMessageService;
  
      public PubRecHandler(IPubRelMessageService pubRelMessageService, IPublishMessageService publishMessageService,
                           MqttxConfig config) {
          super(config.getCluster().getEnable());
          this.pubRelMessageService = pubRelMessageService;
          this.publishMessageService = publishMessageService;
      }
  
      @Override
      public void process(ChannelHandlerContext ctx, MqttMessage msg) {
          // 移除消息
          final var mqttMessageIdVariableHeader = (MqttMessageIdVariableHeader) msg.variableHeader();
          int messageId = mqttMessageIdVariableHeader.messageId();
          if (isCleanSession(ctx)) {
              Session session = getSession(ctx);
              session.removePubMsg(messageId);
              session.savePubRelOutMsg(messageId);
  
              final var mqttMessage = MqttMessageFactory.newMessage(
                      new MqttFixedHeader(MqttMessageType.PUBREL, false, MqttQoS.AT_LEAST_ONCE, false, 0),
                      MqttMessageIdVariableHeader.from(messageId),
                      null
              );
              ctx.writeAndFlush(mqttMessage);
          } else {
              String clientId = clientId(ctx);
              publishMessageService.remove(clientId, messageId)
                      .then(pubRelMessageService.saveOut(clientId, messageId))
                      .doOnSuccess(unused -> {
                          final var mqttMessage = MqttMessageFactory.newMessage(
                                  new MqttFixedHeader(MqttMessageType.PUBREL, false, MqttQoS.AT_LEAST_ONCE, false, 0),
                                  MqttMessageIdVariableHeader.from(messageId),
                                  null
                          );
                          ctx.writeAndFlush(mqttMessage);
                      })
                      .subscribe();
          }
      }
  }
  