/* 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.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Runtime.Serialization;
using OpenSearch.Net.Utf8Json;

namespace OpenSearch.Client.Specification.IngestApi
{
	[InterfaceDataContract]
	public interface IAppendProcessor : IProcessor
	{
		[DataMember(Name ="field")]
		Field Field { get; set; }

		[DataMember(Name ="value")]
		IEnumerable<object> Value { get; set; }

		[DataMember(Name = "allow_duplicates")]
		bool? AllowDuplicates { get; set; }
	}

	public class AppendProcessor : ProcessorBase, IAppendProcessor
	{
		public Field Field { get; set; }
		public IEnumerable<object> Value { get; set; }
		public bool? AllowDuplicates { get; set; }

		protected override string Name => "append";
	}

	public class AppendProcessorDescriptor<T> : ProcessorDescriptorBase<AppendProcessorDescriptor<T>, IAppendProcessor>, IAppendProcessor
		where T : class
	{
		protected override string Name => "append";
		Field IAppendProcessor.Field { get; set; }
		IEnumerable<object> IAppendProcessor.Value { get; set; }
		bool? IAppendProcessor.AllowDuplicates { get; set; }

		public AppendProcessorDescriptor<T> Field(Field field) => Assign(field, (a, v) => a.Field = v);

		public AppendProcessorDescriptor<T> Field<TValue>(Expression<Func<T, TValue>> objectPath) =>
			Assign(objectPath, (a, v) => a.Field = v);

		public AppendProcessorDescriptor<T> Value<TValue>(IEnumerable<TValue> values) => Assign(values, (a, v) => a.Value = v?.Cast<object>());

		public AppendProcessorDescriptor<T> Value<TValue>(params TValue[] values) => Assign(values, (a, v) =>
		{
			if (v?.Length == 1 && typeof(IEnumerable).IsAssignableFrom(typeof(TValue)) && typeof(TValue) != typeof(string))
				a.Value = (v.First() as IEnumerable)?.Cast<object>();
			else a.Value = v?.Cast<object>();
		});

		public AppendProcessorDescriptor<T> AllowDuplicates(bool? allowDuplicates = true) => Assign(allowDuplicates, (a, v) => a.AllowDuplicates = v);
	}
}