/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

package org.elasticsearch.search.aggregations.bucket.terms;

import org.apache.lucene.util.BytesRef;
import org.elasticsearch.common.util.Maps;
import org.elasticsearch.search.DocValueFormat;
import org.elasticsearch.search.aggregations.InternalAggregations;
import org.elasticsearch.search.aggregations.bucket.terms.heuristic.SignificanceHeuristic;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class SignificantStringTermsTests extends InternalSignificantTermsTestCase {

    @Override
    protected InternalSignificantTerms<?, ?> createTestInstance(
        String name,
        Map<String, Object> metadata,
        InternalAggregations aggs,
        int requiredSize,
        int numBuckets,
        long subsetSize,
        int[] subsetDfs,
        long supersetSize,
        int[] supersetDfs,
        SignificanceHeuristic significanceHeuristic
    ) {
        DocValueFormat format = DocValueFormat.RAW;
        List<SignificantStringTerms.Bucket> buckets = new ArrayList<>(numBuckets);
        Set<BytesRef> terms = new HashSet<>();
        for (int i = 0; i < numBuckets; ++i) {
            BytesRef term = randomValueOtherThanMany(b -> terms.add(b) == false, () -> new BytesRef(randomAlphaOfLength(10)));
            SignificantStringTerms.Bucket bucket = new SignificantStringTerms.Bucket(term, subsetDfs[i], supersetDfs[i], aggs, format, 0);
            bucket.updateScore(significanceHeuristic, subsetSize, supersetSize);
            buckets.add(bucket);
        }
        return new SignificantStringTerms(
            name,
            requiredSize,
            1L,
            metadata,
            format,
            subsetSize,
            supersetSize,
            significanceHeuristic,
            buckets
        );
    }

    @Override
    protected InternalSignificantTerms<?, ?> mutateInstance(InternalSignificantTerms<?, ?> instance) {
        if (instance instanceof SignificantStringTerms stringTerms) {
            String name = stringTerms.getName();
            int requiredSize = stringTerms.requiredSize;
            long minDocCount = stringTerms.minDocCount;
            DocValueFormat format = stringTerms.format;
            long subsetSize = stringTerms.getSubsetSize();
            long supersetSize = stringTerms.getSupersetSize();
            List<SignificantStringTerms.Bucket> buckets = stringTerms.getBuckets();
            SignificanceHeuristic significanceHeuristic = stringTerms.significanceHeuristic;
            Map<String, Object> metadata = stringTerms.getMetadata();
            switch (between(0, 6)) {
                case 0 -> name += randomAlphaOfLength(5);
                case 1 -> requiredSize += between(1, 100);
                case 2 -> minDocCount += between(1, 100);
                case 3 -> subsetSize += between(1, 100);
                case 4 -> supersetSize += between(1, 100);
                case 5 -> {
                    buckets = new ArrayList<>(buckets);
                    buckets.add(
                        new SignificantStringTerms.Bucket(
                            new BytesRef(randomAlphaOfLengthBetween(1, 10)),
                            randomNonNegativeLong(),
                            randomNonNegativeLong(),
                            InternalAggregations.EMPTY,
                            format,
                            0
                        )
                    );
                }
                case 6 -> {
                    if (metadata == null) {
                        metadata = Maps.newMapWithExpectedSize(1);
                    } else {
                        metadata = new HashMap<>(instance.getMetadata());
                    }
                    metadata.put(randomAlphaOfLength(15), randomInt());
                }
                default -> throw new AssertionError("Illegal randomisation branch");
            }
            return new SignificantStringTerms(
                name,
                requiredSize,
                minDocCount,
                metadata,
                format,
                subsetSize,
                supersetSize,
                significanceHeuristic,
                buckets
            );
        } else {
            String name = instance.getName();
            int requiredSize = instance.requiredSize;
            long minDocCount = instance.minDocCount;
            Map<String, Object> metadata = instance.getMetadata();
            switch (between(0, 3)) {
                case 0 -> name += randomAlphaOfLength(5);
                case 1 -> requiredSize += between(1, 100);
                case 2 -> minDocCount += between(1, 100);
                case 3 -> {
                    if (metadata == null) {
                        metadata = Maps.newMapWithExpectedSize(1);
                    } else {
                        metadata = new HashMap<>(instance.getMetadata());
                    }
                    metadata.put(randomAlphaOfLength(15), randomInt());
                }
                default -> throw new AssertionError("Illegal randomisation branch");
            }
            return new UnmappedSignificantTerms(name, requiredSize, minDocCount, metadata);
        }
    }
}