/*
    * 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.infra.parser.sql;
  
  import lombok.Getter;
  import org.apache.shardingsphere.database.connector.core.type.DatabaseType;
  import org.apache.shardingsphere.infra.parser.cache.CacheManager;
  import org.apache.shardingsphere.infra.parser.cache.SQLStatementCacheBuilder;
  import org.apache.shardingsphere.infra.parser.cache.SQLStatementCacheLoader;
  import org.apache.shardingsphere.sql.parser.engine.api.CacheOption;
  import org.apache.shardingsphere.sql.parser.statement.core.statement.SQLStatement;
  
  /**
   * SQL statement parser engine.
   */
  public final class SQLStatementParserEngine {
      
      private final SQLStatementParserExecutor sqlStatementParserExecutor;
      
      private final CacheManager<String, SQLStatement> sqlStatementCacheManager;
      
      @Getter
      private final CacheOption sqlStatementCacheOption;
      
      @Getter
      private final CacheOption parseTreeCacheOption;
      
      public SQLStatementParserEngine(final DatabaseType databaseType, final CacheOption sqlStatementCacheOption, final CacheOption parseTreeCacheOption) {
          sqlStatementParserExecutor = new SQLStatementParserExecutor(databaseType, parseTreeCacheOption);
          sqlStatementCacheManager = SQLStatementCacheBuilder.build(databaseType, sqlStatementCacheOption, parseTreeCacheOption);
          this.sqlStatementCacheOption = sqlStatementCacheOption;
          this.parseTreeCacheOption = parseTreeCacheOption;
      }
      
      /**
       * Update cache option.
       *
       * @param sqlStatementCacheOption SQL statement cache option
       * @param parseTreeCacheOption parse tree cache option
       */
      public void updateCacheOption(final CacheOption sqlStatementCacheOption, final CacheOption parseTreeCacheOption) {
          sqlStatementCacheManager.getCache().policy().eviction().ifPresent(eviction -> eviction.setMaximum(sqlStatementCacheOption.getMaximumSize()));
          ((SQLStatementCacheLoader) sqlStatementCacheManager.getCacheLoader()).updateCacheOption(parseTreeCacheOption);
          sqlStatementParserExecutor.updateCacheOption(parseTreeCacheOption);
      }
      
      /**
       * Parse to SQL statement.
       *
       * @param sql SQL to be parsed
       * @param useCache whether to use cache
       * @return SQL statement
       */
      public SQLStatement parse(final String sql, final boolean useCache) {
          return useCache ? sqlStatementCacheManager.getCache().get(sql) : sqlStatementParserExecutor.parse(sql);
      }
  }