/*
 * 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 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 or the Server
 * Side Public License, v 1.
 */

package org.elasticsearch.index.reindex;

import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.index.mapper.IdFieldMapper;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.test.ESTestCase;

import java.io.IOException;

import static java.util.Collections.emptyList;
import static org.elasticsearch.index.reindex.BulkByScrollParallelizationHelper.sliceIntoSubRequests;
import static org.elasticsearch.search.RandomSearchRequestGenerator.randomSearchRequest;
import static org.elasticsearch.search.RandomSearchRequestGenerator.randomSearchSourceBuilder;

public class BulkByScrollParallelizationHelperTests extends ESTestCase {
    public void testSliceIntoSubRequests() throws IOException {
        SearchRequest searchRequest = randomSearchRequest(() -> randomSearchSourceBuilder(
                () -> null,
                () -> null,
                () -> null,
                () -> emptyList(),
                () -> null,
                () -> null));
        if (searchRequest.source() != null) {
            // Clear the slice builder if there is one set. We can't call sliceIntoSubRequests if it is.
            searchRequest.source().slice(null);
        }
        int times = between(2, 100);
        String field = randomBoolean() ? IdFieldMapper.NAME : randomAlphaOfLength(5);
        int currentSliceId = 0;
        for (SearchRequest slice : sliceIntoSubRequests(searchRequest, field, times)) {
            assertEquals(field, slice.source().slice().getField());
            assertEquals(currentSliceId, slice.source().slice().getId());
            assertEquals(times, slice.source().slice().getMax());

            // If you clear the slice then the slice should be the same request as the parent request
            slice.source().slice(null);
            if (searchRequest.source() == null) {
                // Except that adding the slice might have added an empty builder
                searchRequest.source(new SearchSourceBuilder());
            }
            assertEquals(searchRequest, slice);
            currentSliceId++;
        }
    }
}
