/*
    * 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.distsql.parser.core;
  
  import org.antlr.v4.runtime.tree.ParseTree;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementBaseVisitor;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.AlgorithmDefinitionContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.AlterEncryptRuleContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.CountEncryptRuleContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.CreateEncryptRuleContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.DatabaseNameContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.DropEncryptRuleContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.EncryptColumnDefinitionContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.EncryptRuleDefinitionContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.PropertiesDefinitionContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.PropertyContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.ShowEncryptAlgorithmPluginsContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.ShowEncryptRulesContext;
  import org.apache.shardingsphere.distsql.parser.autogen.EncryptDistSQLStatementParser.TableNameContext;
  import org.apache.shardingsphere.distsql.segment.AlgorithmSegment;
  import org.apache.shardingsphere.distsql.statement.ral.queryable.show.ShowPluginsStatement;
  import org.apache.shardingsphere.distsql.statement.rql.rule.database.CountRuleStatement;
  import org.apache.shardingsphere.encrypt.distsql.segment.EncryptColumnItemSegment;
  import org.apache.shardingsphere.encrypt.distsql.segment.EncryptColumnSegment;
  import org.apache.shardingsphere.encrypt.distsql.segment.EncryptRuleSegment;
  import org.apache.shardingsphere.encrypt.distsql.statement.AlterEncryptRuleStatement;
  import org.apache.shardingsphere.encrypt.distsql.statement.CreateEncryptRuleStatement;
  import org.apache.shardingsphere.encrypt.distsql.statement.DropEncryptRuleStatement;
  import org.apache.shardingsphere.encrypt.distsql.statement.ShowEncryptRulesStatement;
  import org.apache.shardingsphere.infra.database.core.metadata.database.enums.QuoteCharacter;
  import org.apache.shardingsphere.sql.parser.api.ASTNode;
  import org.apache.shardingsphere.sql.parser.api.visitor.SQLVisitor;
  import org.apache.shardingsphere.sql.parser.statement.core.segment.dal.FromDatabaseSegment;
  import org.apache.shardingsphere.sql.parser.statement.core.segment.generic.DatabaseSegment;
  import org.apache.shardingsphere.sql.parser.statement.core.segment.generic.table.TableNameSegment;
  import org.apache.shardingsphere.sql.parser.statement.core.value.identifier.IdentifierValue;
  
  import java.util.Properties;
  import java.util.stream.Collectors;
  
  /**
   * SQL statement visitor for encrypt DistSQL.
   */
  public final class EncryptDistSQLStatementVisitor extends EncryptDistSQLStatementBaseVisitor<ASTNode> implements SQLVisitor<ASTNode> {
      
      @Override
      public ASTNode visitCreateEncryptRule(final CreateEncryptRuleContext ctx) {
          return new CreateEncryptRuleStatement(null != ctx.ifNotExists(), ctx.encryptRuleDefinition().stream().map(each -> (EncryptRuleSegment) visit(each)).collect(Collectors.toList()));
      }
      
      @Override
      public ASTNode visitAlterEncryptRule(final AlterEncryptRuleContext ctx) {
          return new AlterEncryptRuleStatement(ctx.encryptRuleDefinition().stream().map(each -> (EncryptRuleSegment) visit(each)).collect(Collectors.toList()));
      }
      
      @Override
      public ASTNode visitDropEncryptRule(final DropEncryptRuleContext ctx) {
          return new DropEncryptRuleStatement(null != ctx.ifExists(), ctx.tableName().stream().map(this::getIdentifierValue).collect(Collectors.toList()));
      }
      
      @Override
      public ASTNode visitShowEncryptRules(final ShowEncryptRulesContext ctx) {
          return new ShowEncryptRulesStatement(null == ctx.tableRule()
                  ? null
                  : getIdentifierValue(ctx.tableRule().tableName()),
                  null == ctx.databaseName() ? null : new FromDatabaseSegment(ctx.FROM().getSymbol().getStartIndex(), (DatabaseSegment) visit(ctx.databaseName())));
      }
      
      @Override
      public ASTNode visitEncryptRuleDefinition(final EncryptRuleDefinitionContext ctx) {
          return new EncryptRuleSegment(getIdentifierValue(ctx.tableName()),
                  ctx.encryptTableRuleDefinition().encryptColumnDefinition().stream().map(each -> (EncryptColumnSegment) visit(each)).collect(Collectors.toList()));
      }
      
      @Override
      public ASTNode visitEncryptColumnDefinition(final EncryptColumnDefinitionContext ctx) {
          EncryptColumnItemSegment cipher = new EncryptColumnItemSegment(
                  getIdentifierValue(ctx.cipherColumnDefinition().cipherColumnName()), (AlgorithmSegment) visit(ctx.encryptAlgorithm().algorithmDefinition()));
          EncryptColumnItemSegment assistedQuery = null == ctx.assistedQueryColumnDefinition()
                  ? null
                  : new EncryptColumnItemSegment(getIdentifierValue(ctx.assistedQueryColumnDefinition().assistedQueryColumnName()), getAssistedEncryptor(ctx));
          EncryptColumnItemSegment likeQuery = null == ctx.likeQueryColumnDefinition()
                  ? null
                  : new EncryptColumnItemSegment(getIdentifierValue(ctx.likeQueryColumnDefinition().likeQueryColumnName()), getLikeEncryptor(ctx));
         return new EncryptColumnSegment(getIdentifierValue(ctx.columnDefinition().columnName()), cipher, assistedQuery, likeQuery);
     }
     
     private AlgorithmSegment getAssistedEncryptor(final EncryptColumnDefinitionContext ctx) {
         return null == ctx.assistedQueryAlgorithm() ? null : (AlgorithmSegment) visit(ctx.assistedQueryAlgorithm().algorithmDefinition());
     }
     
     private AlgorithmSegment getLikeEncryptor(final EncryptColumnDefinitionContext ctx) {
         return null == ctx.likeQueryAlgorithm() ? null : (AlgorithmSegment) visit(ctx.likeQueryAlgorithm().algorithmDefinition());
     }
     
     @Override
     public ASTNode visitAlgorithmDefinition(final AlgorithmDefinitionContext ctx) {
         return new AlgorithmSegment(getIdentifierValue(ctx.algorithmTypeName()), getProperties(ctx.propertiesDefinition()));
     }
     
     private String getIdentifierValue(final ParseTree context) {
         return null == context ? null : new IdentifierValue(context.getText()).getValue();
     }
     
     private Properties getProperties(final PropertiesDefinitionContext ctx) {
         Properties result = new Properties();
         if (null == ctx || null == ctx.properties()) {
             return result;
         }
         for (PropertyContext each : ctx.properties().property()) {
             result.setProperty(QuoteCharacter.unwrapAndTrimText(each.key.getText()), QuoteCharacter.unwrapAndTrimText(each.value.getText()));
         }
         return result;
     }
     
     @Override
     public ASTNode visitTableName(final TableNameContext ctx) {
         return new TableNameSegment(ctx.getStart().getStartIndex(), ctx.getStop().getStopIndex(), new IdentifierValue(ctx.getText()));
     }
     
     @Override
     public ASTNode visitDatabaseName(final DatabaseNameContext ctx) {
         return new DatabaseSegment(ctx.getStart().getStartIndex(), ctx.getStop().getStopIndex(), new IdentifierValue(ctx.getText()));
     }
     
     @Override
     public ASTNode visitCountEncryptRule(final CountEncryptRuleContext ctx) {
         return new CountRuleStatement(null == ctx.databaseName() ? null : new FromDatabaseSegment(ctx.FROM().getSymbol().getStartIndex(), (DatabaseSegment) visit(ctx.databaseName())), "ENCRYPT");
     }
     
     @Override
     public ASTNode visitShowEncryptAlgorithmPlugins(final ShowEncryptAlgorithmPluginsContext ctx) {
         return new ShowPluginsStatement("ENCRYPT_ALGORITHM");
     }
 }