/*
 * 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.gravitino.cli;

import org.apache.gravitino.rel.Column;
import org.apache.gravitino.rel.expressions.Expression;
import org.apache.gravitino.rel.expressions.literals.Literals;
import org.apache.gravitino.rel.types.Type;

/**
 * DefaultConverter is a utility class that converts a default value string to the appropriate
 * internal default value.
 */
public class DefaultConverter {

  /**
   * Converts a default value string to the appropriate internal default value.
   *
   * @param defaultValue The string representing the default value i.e. "current_timestamp" or a
   *     literal value.
   * @param dataType The string representing the default type.
   * @return An instance of the appropriate default value.
   */
  public static Expression convert(String defaultValue, String dataType) {

    if (dataType == null || dataType.isEmpty()) {
      return Column.DEFAULT_VALUE_NOT_SET;
    }

    Type convertedDatatype = ParseType.toType(dataType);

    if (defaultValue == null || defaultValue.isEmpty()) {
      return Column.DEFAULT_VALUE_NOT_SET;
    } else if (defaultValue.equalsIgnoreCase("current_timestamp")) {
      return Column.DEFAULT_VALUE_OF_CURRENT_TIMESTAMP;
    } else {
      return Literals.of(defaultValue, convertedDatatype);
    }
  }
}
