/*
    * 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.encrypt.rule.changed;
  
  import org.apache.shardingsphere.encrypt.api.config.EncryptRuleConfiguration;
  import org.apache.shardingsphere.encrypt.metadata.nodepath.EncryptRuleNodePathProvider;
  import org.apache.shardingsphere.encrypt.rule.EncryptRule;
  import org.apache.shardingsphere.infra.algorithm.core.config.AlgorithmConfiguration;
  import org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabase;
  import org.apache.shardingsphere.infra.rule.event.rule.alter.AlterNamedRuleItemEvent;
  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.infra.algorithm.core.yaml.YamlAlgorithmConfiguration;
  import org.apache.shardingsphere.infra.algorithm.core.yaml.YamlAlgorithmConfigurationSwapper;
  import org.apache.shardingsphere.mode.spi.RuleItemConfigurationChangedProcessor;
  
  import java.util.LinkedHashMap;
  import java.util.LinkedList;
  
  /**
   * Encryptor changed processor.
   */
  public final class EncryptorChangedProcessor implements RuleItemConfigurationChangedProcessor<EncryptRuleConfiguration, AlgorithmConfiguration> {
      
      @Override
      public AlgorithmConfiguration swapRuleItemConfiguration(final AlterRuleItemEvent event, final String yamlContent) {
          return new YamlAlgorithmConfigurationSwapper().swapToObject(YamlEngine.unmarshal(yamlContent, YamlAlgorithmConfiguration.class));
      }
      
      @Override
      public EncryptRuleConfiguration findRuleConfiguration(final ShardingSphereDatabase database) {
          return database.getRuleMetaData().findSingleRule(EncryptRule.class)
                  .map(optional -> getEncryptRuleConfiguration(optional.getConfiguration()))
                  .orElseGet(() -> new EncryptRuleConfiguration(new LinkedList<>(), new LinkedHashMap<>()));
      }
      
      private EncryptRuleConfiguration getEncryptRuleConfiguration(final EncryptRuleConfiguration config) {
          return null == config.getTables() ? new EncryptRuleConfiguration(new LinkedList<>(), config.getEncryptors()) : config;
      }
      
      @Override
      public void changeRuleItemConfiguration(final AlterRuleItemEvent event, final EncryptRuleConfiguration currentRuleConfig, final AlgorithmConfiguration toBeChangedItemConfig) {
          currentRuleConfig.getEncryptors().put(((AlterNamedRuleItemEvent) event).getItemName(), toBeChangedItemConfig);
      }
      
      @Override
      public void dropRuleItemConfiguration(final DropRuleItemEvent event, final EncryptRuleConfiguration currentRuleConfig) {
          currentRuleConfig.getEncryptors().remove(((DropNamedRuleItemEvent) event).getItemName());
      }
      
      @Override
      public String getType() {
          return EncryptRuleNodePathProvider.RULE_TYPE + "." + EncryptRuleNodePathProvider.ENCRYPTORS;
      }
  }