/*
 * 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.fielddata;

import org.elasticsearch.index.IndexSettings;
import org.elasticsearch.index.mapper.MappedFieldType;
import org.elasticsearch.search.lookup.SearchLookup;

import java.util.Set;
import java.util.function.Function;
import java.util.function.Supplier;

/**
 * Holds context information for the construction of FieldData
 *
 * @param fullyQualifiedIndexName the index name with any remote index information added
 * @param lookupSupplier a supplier for a SearchLookup to be used by runtime scripts
 * @param sourcePathsLookup a function to get source paths for a specific field
 * @param fielddataOperation the operation used to determine data structures to generate fielddata from
 */
public record FieldDataContext(
    String fullyQualifiedIndexName,
    IndexSettings indexSettings,
    Supplier<SearchLookup> lookupSupplier,
    Function<String, Set<String>> sourcePathsLookup,
    MappedFieldType.FielddataOperation fielddataOperation
) {

    /**
     * A context to use when runtime fields are not available
     *
     * Used for validating index sorts, eager global ordinal loading, etc
     *
     * @param reason the reason that runtime fields are not supported
     */
    public static FieldDataContext noRuntimeFields(String reason) {
        return new FieldDataContext("", null, () -> {
            throw new UnsupportedOperationException("Runtime fields not supported for [" + reason + "]");
        }, Set::of, MappedFieldType.FielddataOperation.SEARCH);
    }
}