package com.ctrip.framework.apollo.internals;

 import com.ctrip.framework.apollo.ConfigFile;

 import com.ctrip.framework.apollo.util.ExceptionUtil;

 import com.dianping.cat.Cat;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import java.util.Properties;

 import java.util.concurrent.atomic.AtomicReference;

 /**

  * @author Jason Song(song_s@ctrip.com)

  */

 public abstract class AbstractConfigFile implements ConfigFile, RepositoryChangeListener {

   private static final Logger logger = LoggerFactory.getLogger(AbstractConfigFile.class);

   protected ConfigRepository m_configRepository;

   protected String m_namespace;

   protected AtomicReference<Properties> m_configProperties;

   public AbstractConfigFile(String namespace, ConfigRepository configRepository) {

     m_configRepository = configRepository;

     m_namespace = namespace;

     m_configProperties = new AtomicReference<>();

     initialize();

   }

   private void initialize() {

     try {

       m_configProperties.set(m_configRepository.getConfig());

     } catch (Throwable ex) {

       Cat.logError(ex);

       logger.warn("Init Apollo Config File failed - namespace: {}, reason: {}.",

           m_namespace, ExceptionUtil.getDetailMessage(ex));

     } finally {

       //register the change listener no matter config repository is working or not

       //so that whenever config repository is recovered, config could get changed

       m_configRepository.addChangeListener(this);

     }

   }

   @Override

   public String getNamespace() {

     return m_namespace;

   }

   @Override

   public synchronized void onRepositoryChange(String namespace, Properties newProperties) {

     if (newProperties.equals(m_configProperties.get())) {

       return;

     }

     Properties newConfigProperties = new Properties();

     newConfigProperties.putAll(newProperties);

     m_configProperties.set(newConfigProperties);

     Cat.logEvent("Apollo.Client.ConfigChanges", m_namespace);

   }

 }