/*
 * 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.index.fieldstats;

import org.elasticsearch.action.DocWriteResponse;
import org.elasticsearch.action.search.SearchType;
import org.elasticsearch.action.support.broadcast.BroadcastResponse;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.indices.IndicesRequestCache;
import org.elasticsearch.rest.RestStatus;
import org.elasticsearch.test.ESSingleNodeTestCase;

import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertNoFailuresAndResponse;
import static org.hamcrest.Matchers.anyOf;
import static org.hamcrest.Matchers.equalTo;

public class FieldStatsProviderRefreshTests extends ESSingleNodeTestCase {

    public void testQueryRewriteOnRefresh() throws Exception {
        assertAcked(
            indicesAdmin().prepareCreate("index")
                .setMapping("s", "type=text")
                .setSettings(indexSettings(1, 0).put(IndicesRequestCache.INDEX_CACHE_REQUEST_ENABLED_SETTING.getKey(), true))
        );

        // Index some documents
        indexDocument("1", "d");
        indexDocument("2", "e");
        indexDocument("3", "f");
        refreshIndex();

        // check request cache stats are clean
        assertRequestCacheStats(0, 0);

        // Search for a range and check that it missed the cache (since its the
        // first time it has run)
        assertNoFailuresAndResponse(
            client().prepareSearch("index")
                .setSearchType(SearchType.QUERY_THEN_FETCH)
                .setSize(0)
                .setQuery(QueryBuilders.rangeQuery("s").gte("a").lte("g")),
            r1 -> assertThat(r1.getHits().getTotalHits().value(), equalTo(3L))
        );
        assertRequestCacheStats(0, 1);

        // Search again and check it hits the cache
        assertNoFailuresAndResponse(
            client().prepareSearch("index")
                .setSearchType(SearchType.QUERY_THEN_FETCH)
                .setSize(0)
                .setQuery(QueryBuilders.rangeQuery("s").gte("a").lte("g")),
            r2 -> assertThat(r2.getHits().getTotalHits().value(), equalTo(3L))
        );
        assertRequestCacheStats(1, 1);

        // Index some more documents in the query range and refresh
        indexDocument("4", "c");
        indexDocument("5", "g");
        refreshIndex();

        // Search again and check the request cache for another miss since request cache should be invalidated by refresh
        assertNoFailuresAndResponse(
            client().prepareSearch("index")
                .setSearchType(SearchType.QUERY_THEN_FETCH)
                .setSize(0)
                .setQuery(QueryBuilders.rangeQuery("s").gte("a").lte("g")),
            r3 -> assertThat(r3.getHits().getTotalHits().value(), equalTo(5L))
        );
        assertRequestCacheStats(1, 2);
    }

    private void assertRequestCacheStats(long expectedHits, long expectedMisses) {
        assertThat(
            indicesAdmin().prepareStats("index").setRequestCache(true).get().getTotal().getRequestCache().getHitCount(),
            equalTo(expectedHits)
        );
        assertThat(
            indicesAdmin().prepareStats("index").setRequestCache(true).get().getTotal().getRequestCache().getMissCount(),
            equalTo(expectedMisses)
        );
    }

    private void refreshIndex() {
        BroadcastResponse refreshResponse = indicesAdmin().prepareRefresh("index").get();
        assertThat(refreshResponse.getSuccessfulShards(), equalTo(refreshResponse.getSuccessfulShards()));
    }

    private void indexDocument(String id, String sValue) {
        DocWriteResponse response = prepareIndex("index").setId(id).setSource("s", sValue).get();
        assertThat(response.status(), anyOf(equalTo(RestStatus.OK), equalTo(RestStatus.CREATED)));
    }
}