content: /**
   * 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.bigtop.datagenerators.weatherman.internal;
  
  import java.util.Collection;
  
  import org.apache.bigtop.datagenerators.locations.Location;
  import org.apache.bigtop.datagenerators.samplers.SeedFactory;
  import org.apache.bigtop.datagenerators.samplers.samplers.ConditionalSampler;
  import org.apache.bigtop.datagenerators.samplers.samplers.Sampler;
  import org.apache.bigtop.datagenerators.weatherman.WeatherRecord;
  import org.joda.time.LocalDate;
  
  public class WeatherSamplerBuilder {
  
    private final WeatherStationParameters parameters;
    private final SeedFactory seedFactory;
    private final LocalDate startDate;
  
    public WeatherSamplerBuilder(
            Collection<WeatherStationParameters> weatherParameters,
            Location location, LocalDate startDate, SeedFactory seedFactory) {
      parameters = findClosest(weatherParameters, location);
      this.seedFactory = seedFactory;
      this.startDate = startDate;
    }
  
    private WeatherStationParameters findClosest(
            Collection<WeatherStationParameters> weatherParameters,
            Location location) {
      WeatherStationParameters closestStation = null;
      double minDist = Double.MAX_VALUE;
  
      for (WeatherStationParameters parameters : weatherParameters) {
        double dist = location.distance(parameters.getCoordinates());
        if (dist < minDist) {
          minDist = dist;
          closestStation = parameters;
        }
      }
  
      return closestStation;
    }
  
    private ConditionalSampler<WeatherRecordBuilder, WeatherRecordBuilder> buildTempSampler() {
      return new TemperatureSampler(startDate, parameters.getTemperatureAverage(),
              parameters.getTemperatureRealCoeff(),
              parameters.getTemperatureImagCoeff(),
              parameters.getTemperatureDerivStd(), seedFactory);
    }
  
    private ConditionalSampler<WeatherRecordBuilder, WeatherRecordBuilder> buildWindSpeedSampler() {
      return new WindSpeedSampler(parameters.getWindSpeedRealCoeff(),
              parameters.getWindSpeedImagCoeff(), parameters.getWindSpeedK(),
              parameters.getWindSpeedTheta(), seedFactory);
    }
  
    private ConditionalSampler<WeatherRecordBuilder, WeatherRecordBuilder> buildPrecipitationSampler() {
      return new PrecipitationSampler(parameters.getPrecipitationAverage(),
              seedFactory);
    }
  
    public Sampler<WeatherRecord> build() {
      return new WeatherSampler(startDate, buildTempSampler(),
              buildWindSpeedSampler(), buildPrecipitationSampler());
    }
  }
  