/* SPDX-License-Identifier: Apache-2.0
*
* The OpenSearch Contributors require contributions made to
* this file be licensed under the Apache-2.0 license or a
* compatible open source license.
*/
/*
* Modifications Copyright OpenSearch Contributors. See
* GitHub history for details.
*
*  Licensed to Elasticsearch B.V. under one or more contributor
*  license agreements. See the NOTICE file distributed with
*  this work for additional information regarding copyright
*  ownership. Elasticsearch B.V. licenses this file to you under
*  the Apache License, Version 2.0 (the "License"); you may
*  not use this file except in compliance with the License.
*  You may obtain a copy of the License at
*
* 	http://www.apache.org/licenses/LICENSE-2.0
*
*  Unless required by applicable law or agreed to in writing,
*  software distributed under the License is distributed on an
*  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
*  KIND, either express or implied.  See the License for the
*  specific language governing permissions and limitations
*  under the License.
*/

using System;
using System.Linq.Expressions;
using System.Runtime.Serialization;
using OpenSearch.Net.Utf8Json;

namespace OpenSearch.Client.Specification.IngestApi
{
	/// <summary>
	/// Joins each element of an array into a single string using a separator
	/// character between each element. Throws an error when the field is not an array.
	/// </summary>
	[InterfaceDataContract]
	public interface IJoinProcessor : IProcessor
	{
		/// <summary>
		/// The field to be joined
		/// </summary>
		[DataMember(Name ="field")]
		Field Field { get; set; }

		/// <summary>
		/// The separator character
		/// </summary>
		[DataMember(Name ="separator")]
		string Separator { get; set; }

		/// <summary>
		/// The field to assign the joined value to, by default field is updated in-place
		/// </summary>
		[DataMember(Name = "target_field")]
		Field TargetField { get; set; }
	}

	/// <inheritdoc cref="IJoinProcessor"/>
	public class JoinProcessor : ProcessorBase, IJoinProcessor
	{
		/// <inheritdoc />
		public Field Field { get; set; }
		/// <inheritdoc />
		public string Separator { get; set; }
		/// <inheritdoc />
		public Field TargetField { get; set; }
		protected override string Name => "join";
	}

	/// <inheritdoc cref="IJoinProcessor"/>
	public class JoinProcessorDescriptor<T>
		: ProcessorDescriptorBase<JoinProcessorDescriptor<T>, IJoinProcessor>, IJoinProcessor
		where T : class
	{
		protected override string Name => "join";

		Field IJoinProcessor.Field { get; set; }
		Field IJoinProcessor.TargetField { get; set; }
		string IJoinProcessor.Separator { get; set; }

		/// <inheritdoc cref="IJoinProcessor.Field"/>
		public JoinProcessorDescriptor<T> Field(Field field) => Assign(field, (a, v) => a.Field = v);

		/// <inheritdoc cref="IJoinProcessor.Field"/>
		public JoinProcessorDescriptor<T> Field<TValue>(Expression<Func<T, TValue>> objectPath) =>
			Assign(objectPath, (a, v) => a.Field = v);

		/// <inheritdoc cref="IJoinProcessor.TargetField"/>
		public JoinProcessorDescriptor<T> TargetField(Field field) => Assign(field, (a, v) => a.TargetField = v);

		/// <inheritdoc cref="IJoinProcessor.TargetField"/>
		public JoinProcessorDescriptor<T> TargetField(Expression<Func<T, object>> objectPath) =>
			Assign(objectPath, (a, v) => a.TargetField = v);

		/// <inheritdoc cref="IJoinProcessor.Separator"/>
		public JoinProcessorDescriptor<T> Separator(string separator) => Assign(separator, (a, v) => a.Separator = v);
	}
}