/**
 * 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.client;

import java.util.ArrayList;
import java.util.List;
import org.json.JSONException;
import org.json.JSONObject;


/**
 * A Pinot result set group, containing the results given back by Pinot for a given query.
 */
public class ResultSetGroup {
  private final List<ResultSet> _resultSets;

  ResultSetGroup(BrokerResponse brokerResponse) {
    _resultSets = new ArrayList<ResultSet>();

    if (brokerResponse.getSelectionResults() != null) {
      _resultSets.add(new SelectionResultSet(brokerResponse.getSelectionResults()));
    }

    int aggregationResultCount = brokerResponse.getAggregationResultsSize();
    for (int i = 0; i < aggregationResultCount; i++) {
      JSONObject aggregationResult;
      try {
        aggregationResult = brokerResponse.getAggregationResults().getJSONObject(i);
      } catch (JSONException e) {
        throw new PinotClientException(e);
      }
      if (aggregationResult.has("value")) {
        _resultSets.add(new AggregationResultSet(aggregationResult));
      } else if (aggregationResult.has("groupByResult")) {
        _resultSets.add(new GroupByResultSet(aggregationResult));
      } else {
        throw new PinotClientException("Unrecognized result group, neither a value nor group by result");
      }
    }
  }

  /**
   * Returns the number of result sets in this result set group, or 0 if there are no result sets; there is one result
   * set per aggregation function in the original query and one result set in the case of a selection query.
   *
   * @return The number of result sets in this result set
   */
  public int getResultSetCount() {
    return _resultSets.size();
  }

  /**
   * Obtains the result set at the given index, starting from zero.
   *
   * @param index The index for which to obtain the result set
   * @return The result set at the given index
   */
  public ResultSet getResultSet(int index) {
    return _resultSets.get(index);
  }
  
  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder();
    for(ResultSet resultSet:_resultSets){
      sb.append(resultSet);
      sb.append("\n");
    }
    return sb.toString();
  }
}