/*
    * 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.shardingsphere.mode.subsciber;
  
  import com.google.common.eventbus.Subscribe;
  import lombok.RequiredArgsConstructor;
  import org.apache.shardingsphere.infra.config.rule.RuleConfiguration;
  import org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabase;
  import org.apache.shardingsphere.infra.rule.event.rule.alter.AlterRuleItemEvent;
  import org.apache.shardingsphere.infra.rule.event.rule.drop.DropRuleItemEvent;
  import org.apache.shardingsphere.infra.spi.type.typed.TypedSPILoader;
  import org.apache.shardingsphere.mode.event.config.AlterDatabaseRuleConfigurationEvent;
  import org.apache.shardingsphere.mode.event.config.DropDatabaseRuleConfigurationEvent;
  import org.apache.shardingsphere.mode.manager.ContextManager;
  import org.apache.shardingsphere.mode.spi.RuleItemConfigurationChangedProcessor;
  
  /**
   * Rule item changed subscriber.
   */
  @RequiredArgsConstructor
  public final class RuleItemChangedSubscriber {
      
      private final ContextManager contextManager;
      
      /**
       * Renew with alter rule item.
       *
       * @param event alter rule item event
       */
      @SuppressWarnings({"rawtypes", "unchecked", "unused"})
      @Subscribe
      public void renew(final AlterRuleItemEvent event) {
          if (!event.getActiveVersion().equals(contextManager.getMetaDataContexts().getPersistService().getMetaDataVersionPersistService().getActiveVersionByFullPath(event.getActiveVersionKey()))) {
              return;
          }
          RuleItemConfigurationChangedProcessor processor = TypedSPILoader.getService(RuleItemConfigurationChangedProcessor.class, event.getType());
          String yamlContent =
                  contextManager.getMetaDataContexts().getPersistService().getMetaDataVersionPersistService().getVersionPathByActiveVersion(event.getActiveVersionKey(), event.getActiveVersion());
          ShardingSphereDatabase database = contextManager.getMetaDataContexts().getMetaData().getDatabase(event.getDatabaseName());
          RuleConfiguration currentRuleConfig = processor.findRuleConfiguration(database);
          synchronized (this) {
              processor.changeRuleItemConfiguration(event, currentRuleConfig, processor.swapRuleItemConfiguration(event, yamlContent));
              // TODO Remove isCluster judgment
              if (contextManager.getInstanceContext().isCluster()) {
                  contextManager.getInstanceContext().getEventBusContext().post(new AlterDatabaseRuleConfigurationEvent(event.getDatabaseName(), currentRuleConfig));
                  return;
              }
              contextManager.getConfigurationContextManager().alterRuleConfiguration(event.getDatabaseName(), currentRuleConfig);
          }
      }
      
      /**
       * Renew with drop rule item.
       *
       * @param event drop rule item event
       */
      @SuppressWarnings({"rawtypes", "unchecked", "unused"})
      @Subscribe
      public void renew(final DropRuleItemEvent event) {
          if (!contextManager.getMetaDataContexts().getMetaData().containsDatabase(event.getDatabaseName())) {
              return;
          }
          RuleItemConfigurationChangedProcessor processor = TypedSPILoader.getService(RuleItemConfigurationChangedProcessor.class, event.getType());
          ShardingSphereDatabase database = contextManager.getMetaDataContexts().getMetaData().getDatabase(event.getDatabaseName());
          RuleConfiguration currentRuleConfig = processor.findRuleConfiguration(database);
          synchronized (this) {
              processor.dropRuleItemConfiguration(event, currentRuleConfig);
              // TODO Remove isCluster judgment
              if (contextManager.getInstanceContext().isCluster()) {
                  contextManager.getInstanceContext().getEventBusContext().post(new DropDatabaseRuleConfigurationEvent(event.getDatabaseName(), currentRuleConfig));
                  return;
              }
              contextManager.getConfigurationContextManager().dropRuleConfiguration(event.getDatabaseName(), currentRuleConfig);
          }
      }
  }