/*
 * 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.mapper;

import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.IndexSearcher;
import org.elasticsearch.index.query.SearchExecutionContext;
import org.elasticsearch.search.lookup.SearchLookup;

import java.io.IOException;
import java.util.Collections;
import java.util.List;

import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.equalTo;
import static org.hamcrest.Matchers.nullValue;

public class IndexFieldMapperTests extends MetadataMapperTestCase {

    @Override
    protected String fieldName() {
        return IndexFieldMapper.NAME;
    }

    @Override
    protected boolean isConfigurable() {
        return false;
    }

    @Override
    protected void registerParameters(ParameterChecker checker) throws IOException {}

    public void testDefaultDisabledIndexMapper() throws Exception {
        DocumentMapper docMapper = createDocumentMapper(mapping(b -> {}));
        ParsedDocument doc = docMapper.parse(source(b -> b.field("field", "value")));
        assertThat(doc.rootDoc().get("_index"), nullValue());
        assertThat(doc.rootDoc().get("field"), equalTo("value"));
    }

    public void testIndexNotConfigurable() {
        MapperParsingException e = expectThrows(
            MapperParsingException.class,
            () -> createMapperService(topMapping(b -> b.startObject("_index").endObject()))
        );
        assertThat(e.getMessage(), containsString("_index is not configurable"));
    }

    public void testFetchFieldValue() throws IOException {
        MapperService mapperService = createMapperService(fieldMapping(b -> b.field("type", "keyword")));
        String index = mapperService.index().getName();
        withLuceneIndex(mapperService, iw -> {
            SourceToParse source = source(b -> b.field("field", "value"));
            iw.addDocument(mapperService.documentMapper().parse(source).rootDoc());
        }, iw -> {
            IndexFieldMapper.IndexFieldType ft = (IndexFieldMapper.IndexFieldType) mapperService.fieldType("_index");
            SearchLookup lookup = new SearchLookup(mapperService::fieldType, fieldDataLookup(mapperService), (ctx, doc) -> null);
            SearchExecutionContext searchExecutionContext = createSearchExecutionContext(mapperService);
            ValueFetcher valueFetcher = ft.valueFetcher(searchExecutionContext, null);
            IndexSearcher searcher = newSearcher(iw);
            LeafReaderContext context = searcher.getIndexReader().leaves().get(0);
            valueFetcher.setNextReader(context);
            assertEquals(List.of(index), valueFetcher.fetchValues(lookup.getSource(context, 0), 0, Collections.emptyList()));
        });
    }

}