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.service.impl;
  
  import com.jun.mqttx.config.MqttxConfig;
  import com.jun.mqttx.entity.Session;
  import com.jun.mqttx.service.ISessionService;
  import com.jun.mqttx.utils.MessageIdUtils;
  import com.jun.mqttx.utils.Serializer;
  import org.springframework.data.redis.core.ReactiveRedisTemplate;
  import org.springframework.stereotype.Service;
  import org.springframework.util.Assert;
  import reactor.core.publisher.Mono;
  
  import java.util.Objects;
  
  /**
   * 会话服务
   *
   * @author Jun
   * @since 1.0.4
   */
  @Service
  public class DefaultSessionServiceImpl implements ISessionService {
  
      private final String clusterSessionHashKey;
      private final String messageIdPrefix;
      private final ReactiveRedisTemplate<String, byte[]> redisTemplate;
      private final Serializer serializer;
  
      public DefaultSessionServiceImpl(ReactiveRedisTemplate<String, byte[]> redisTemplate,
                                       Serializer serializer,
                                       MqttxConfig mqttxConfig) {
          MqttxConfig.Redis redis = mqttxConfig.getRedis();
          this.redisTemplate = redisTemplate;
          this.serializer = serializer;
          this.clusterSessionHashKey = redis.getClusterSessionHashKey();
          this.messageIdPrefix = redis.getMessageIdPrefix();
      }
  
      @Override
      public Mono<Void> save(Session session) {
          return redisTemplate.opsForHash()
                  .put(clusterSessionHashKey, session.getClientId(), serializer.serialize(session))
                  .then(Mono.empty());
      }
  
      @Override
      public Mono<Session> find(String clientId) {
          return redisTemplate.opsForHash().get(clusterSessionHashKey, clientId)
                  .map(e -> serializer.deserialize((byte[]) e, Session.class));
      }
  
      @Override
      public Mono<Boolean> clear(String clientId) {
          return redisTemplate.delete(messageIdPrefix + clientId)
                  .then(redisTemplate.opsForHash().remove(clusterSessionHashKey, clientId))
                  .switchIfEmpty(Mono.just(-1L))
                  .map(e -> e > 0);
      }
  
      @Override
      public Mono<Boolean> hasKey(String clientId) {
          return redisTemplate.opsForHash().hasKey(clusterSessionHashKey, clientId);
      }
  
      @Override
      public Mono<Integer> nextMessageId(String clientId) {
          return redisTemplate.opsForValue().increment(messageIdPrefix + clientId)
                  .flatMap(e -> {
                      if ((e & 0xffff) == 0) {
                          return redisTemplate.opsForValue().increment(messageIdPrefix + clientId);
                      }
                      return Mono.just(e);
                  })
                  .map(MessageIdUtils::trimMessageId);
      }
  }
  