/*
    * 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.mask.rule.changed;
  
  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.DropNamedRuleItemEvent;
  import org.apache.shardingsphere.infra.rule.event.rule.drop.DropRuleItemEvent;
  import org.apache.shardingsphere.infra.util.yaml.YamlEngine;
  import org.apache.shardingsphere.mask.api.config.MaskRuleConfiguration;
  import org.apache.shardingsphere.mask.api.config.rule.MaskTableRuleConfiguration;
  import org.apache.shardingsphere.mask.metadata.nodepath.MaskRuleNodePathProvider;
  import org.apache.shardingsphere.mask.rule.MaskRule;
  import org.apache.shardingsphere.mask.yaml.config.rule.YamlMaskTableRuleConfiguration;
  import org.apache.shardingsphere.mask.yaml.swapper.rule.YamlMaskTableRuleConfigurationSwapper;
  import org.apache.shardingsphere.mode.spi.RuleItemConfigurationChangedProcessor;
  
  import java.util.LinkedHashMap;
  import java.util.LinkedList;
  
  /**
   * Mask table changed processor.
   */
  public final class MaskTableChangedProcessor implements RuleItemConfigurationChangedProcessor<MaskRuleConfiguration, MaskTableRuleConfiguration> {
      
      @Override
      public MaskTableRuleConfiguration swapRuleItemConfiguration(final AlterRuleItemEvent event, final String yamlContent) {
          return new YamlMaskTableRuleConfigurationSwapper().swapToObject(YamlEngine.unmarshal(yamlContent, YamlMaskTableRuleConfiguration.class));
      }
      
      @Override
      public MaskRuleConfiguration findRuleConfiguration(final ShardingSphereDatabase database) {
          return database.getRuleMetaData().findSingleRule(MaskRule.class)
                  .map(optional -> getConfiguration(optional.getConfiguration())).orElseGet(() -> new MaskRuleConfiguration(new LinkedList<>(), new LinkedHashMap<>()));
      }
      
      private MaskRuleConfiguration getConfiguration(final MaskRuleConfiguration config) {
          return null == config.getTables() ? new MaskRuleConfiguration(new LinkedList<>(), config.getMaskAlgorithms()) : config;
      }
      
      @Override
      public void changeRuleItemConfiguration(final AlterRuleItemEvent event, final MaskRuleConfiguration currentRuleConfig, final MaskTableRuleConfiguration toBeChangedItemConfig) {
          // TODO refactor DistSQL to only persist config
          currentRuleConfig.getTables().removeIf(each -> each.getName().equals(toBeChangedItemConfig.getName()));
          currentRuleConfig.getTables().add(toBeChangedItemConfig);
      }
      
      @Override
      public void dropRuleItemConfiguration(final DropRuleItemEvent event, final MaskRuleConfiguration currentRuleConfig) {
          currentRuleConfig.getTables().removeIf(each -> each.getName().equals(((DropNamedRuleItemEvent) event).getItemName()));
      }
      
      @Override
      public String getType() {
          return MaskRuleNodePathProvider.RULE_TYPE + "." + MaskRuleNodePathProvider.TABLES;
      }
  }