/*
 * 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.phoenix.pherf.rules;

import java.util.concurrent.atomic.AtomicLong;
import org.apache.phoenix.pherf.configuration.Column;
import org.apache.phoenix.pherf.configuration.DataSequence;
import org.apache.phoenix.pherf.configuration.DataTypeMapping;

import org.apache.phoenix.thirdparty.com.google.common.base.Preconditions;

public class SequentialIntegerDataGenerator implements RuleBasedDataGenerator {
  private final Column columnRule;
  private final AtomicLong counter;
  private final long minValue;
  private final long maxValue;

  public SequentialIntegerDataGenerator(Column columnRule) {
    Preconditions.checkArgument(columnRule.getDataSequence() == DataSequence.SEQUENTIAL);
    Preconditions.checkArgument(isIntegerType(columnRule.getType()));
    this.columnRule = columnRule;
    minValue = columnRule.getMinValue();
    maxValue = columnRule.getMaxValue();
    counter = new AtomicLong(0);
  }

  /**
   * Note that this method rolls over for attempts to get larger than maxValue
   * @return new DataValue
   */
  @Override
  public DataValue getDataValue() {
    return new DataValue(columnRule.getType(),
      String.valueOf((counter.getAndIncrement() % (maxValue - minValue + 1)) + minValue));
  }

  // Probably could go into a util class in the future
  boolean isIntegerType(DataTypeMapping mapping) {
    switch (mapping) {
      case BIGINT:
      case INTEGER:
      case TINYINT:
      case UNSIGNED_LONG:
        return true;
      default:
        return false;
    }
  }
}
