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 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.elasticsearch.search.aggregations.metrics;

import org.elasticsearch.common.io.stream.Writeable;
import org.elasticsearch.search.DocValueFormat;
import org.elasticsearch.search.aggregations.metrics.stats.InternalStats;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.test.InternalAggregationTestCase;

import java.util.Collections;
import java.util.List;
import java.util.Map;

public class InternalStatsTests extends InternalAggregationTestCase<InternalStats> {
    @Override
    protected InternalStats createTestInstance(String name, List<PipelineAggregator> pipelineAggregators,
                                               Map<String, Object> metaData) {
        long count = frequently() ? randomIntBetween(1, Integer.MAX_VALUE) : 0;
        double min = randomDoubleBetween(-1000000, 1000000, true);
        double max = randomDoubleBetween(-1000000, 1000000, true);
        double sum = randomDoubleBetween(-1000000, 1000000, true);
        DocValueFormat format = randomNumericDocValueFormat();
        return new InternalStats(name, count, sum, min, max, format, pipelineAggregators, Collections.emptyMap());
    }

    @Override
    protected void assertReduced(InternalStats reduced, List<InternalStats> inputs) {
        long expectedCount = 0;
        double expectedSum = 0;
        double expectedMin = Double.POSITIVE_INFINITY;
        double expectedMax = Double.NEGATIVE_INFINITY;
        for (InternalStats stats : inputs) {
            expectedCount += stats.getCount();
            if (Double.compare(stats.getMin(), expectedMin) < 0) {
                expectedMin = stats.getMin();
            }
            if (Double.compare(stats.getMax(), expectedMax) > 0) {
                expectedMax = stats.getMax();
            }
            expectedSum += stats.getSum();
        }
        assertEquals(expectedCount, reduced.getCount());
        assertEquals(expectedSum, reduced.getSum(), 1e-7);
        assertEquals(expectedMin, reduced.getMin(), 0d);
        assertEquals(expectedMax, reduced.getMax(), 0d);
    }

    @Override
    protected Writeable.Reader<InternalStats> instanceReader() {
        return InternalStats::new;
    }
}