/**
 * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * Licensed 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 com.linkedin.pinot.core.query.pruner;

import com.linkedin.pinot.common.query.ServerQueryRequest;
import com.linkedin.pinot.common.segment.SegmentMetadata;
import com.linkedin.pinot.core.indexsegment.IndexSegment;
import org.apache.commons.configuration.Configuration;


/**
 * Segment pruner class that implements checks to prune a segment with
 * invalid/bad data.
 */
public class ValidSegmentPruner implements SegmentPruner {
  @Override
  public void init(Configuration config) {

  }

  /**
   * Returns true if a segment should be pruned-out due to bad/invalid data.
   * Current check(s) below:
   * - Empty segment.
   *
   * @param segment
   * @param queryRequest
   * @return
   */
  @Override
  public boolean prune(IndexSegment segment, ServerQueryRequest queryRequest) {
    SegmentMetadata segmentMetadata = segment.getSegmentMetadata();

    // Check for empty segment.
    if (segmentMetadata.getTotalDocs() == 0) {
      return true;
    }

    // Add more validation here.

    return false;
  }

  @Override
  public String toString() {
    return "ValidSegmentPruner";
  }
}