content: /*
   * Copyright 2013-2023 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.alibaba.cloud.nacos;
  
  import java.util.Objects;
  
  import com.alibaba.cloud.nacos.diagnostics.analyzer.NacosConnectionFailureException;
  import com.alibaba.nacos.api.NacosFactory;
  import com.alibaba.nacos.api.config.ConfigService;
  import com.alibaba.nacos.api.exception.NacosException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * @author zkzlx
   */
  public class NacosConfigManager {
  
  	private static final Logger log = LoggerFactory.getLogger(NacosConfigManager.class);
  
  	private static ConfigService service;
  
  	private static NacosConfigManager INSTANCE;
  
  	private NacosConfigProperties nacosConfigProperties;
  
  	public NacosConfigManager(NacosConfigProperties nacosConfigProperties) {
  		this.nacosConfigProperties = nacosConfigProperties;
  	}
  
  	public static NacosConfigManager getInstance() {
  		return INSTANCE;
  	}
  
  	public static NacosConfigManager getInstance(NacosConfigProperties properties) {
  		if (INSTANCE != null) {
  			return INSTANCE;
  		}
  		synchronized (NacosConfigManager.class) {
  			if (INSTANCE == null) {
  				INSTANCE = new NacosConfigManager(properties);
  				INSTANCE.createConfigService(properties);
  			}
  		}
  		return INSTANCE;
  	}
  
  	/**
  	 * Compatible with old design,It will be perfected in the future.
  	 */
  	private ConfigService createConfigService(
  			NacosConfigProperties nacosConfigProperties) {
  		try {
  			if (Objects.isNull(service)) {
  				service = NacosFactory.createConfigService(
  						nacosConfigProperties.assembleConfigServiceProperties());
  			}
  		}
  		catch (NacosException e) {
  			log.error(e.getMessage());
  			throw new NacosConnectionFailureException(
  					nacosConfigProperties.getServerAddr(), e.getMessage(), e);
  		}
  		return service;
  	}
  
  	public ConfigService getConfigService() {
  		if (Objects.isNull(service)) {
  			createConfigService(this.nacosConfigProperties);
  		}
  		return service;
  	}
  
  	public NacosConfigProperties getNacosConfigProperties() {
  		return nacosConfigProperties;
  	}
  
  }
  