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

namespace OpenSearch.Client
{
	[InterfaceDataContract]
	[ReadAs(typeof(SpanNearQueryDescriptor<object>))]
	public interface ISpanNearQuery : ISpanSubQuery
	{
		[DataMember(Name ="clauses")]
		IEnumerable<ISpanQuery> Clauses { get; set; }

		[DataMember(Name ="in_order")]
		bool? InOrder { get; set; }

		[DataMember(Name ="slop")]
		int? Slop { get; set; }
	}

	public class SpanNearQuery : QueryBase, ISpanNearQuery
	{
		public IEnumerable<ISpanQuery> Clauses { get; set; }
		public bool? InOrder { get; set; }
		public int? Slop { get; set; }
		protected override bool Conditionless => IsConditionless(this);

		internal override void InternalWrapInContainer(IQueryContainer c) => c.SpanNear = this;

		internal static bool IsConditionless(ISpanNearQuery q) => !q.Clauses.HasAny() || q.Clauses.Cast<IQuery>().All(qq => qq.Conditionless);
	}

	public class SpanNearQueryDescriptor<T>
		: QueryDescriptorBase<SpanNearQueryDescriptor<T>, ISpanNearQuery>
			, ISpanNearQuery where T : class
	{
		protected override bool Conditionless => SpanNearQuery.IsConditionless(this);
		IEnumerable<ISpanQuery> ISpanNearQuery.Clauses { get; set; }
		bool? ISpanNearQuery.InOrder { get; set; }
		int? ISpanNearQuery.Slop { get; set; }

		public SpanNearQueryDescriptor<T> Clauses(params Func<SpanQueryDescriptor<T>, SpanQueryDescriptor<T>>[] selectors) =>
			Clauses(selectors.ToList());

		public SpanNearQueryDescriptor<T> Clauses(IEnumerable<Func<SpanQueryDescriptor<T>, SpanQueryDescriptor<T>>> selectors) => Assign(selectors, (a, v) =>
		{
			a.Clauses = v.Select(selector => selector?.Invoke(new SpanQueryDescriptor<T>()))
				.Where(query => query != null && !((IQuery)query).Conditionless)
				.ToListOrNullIfEmpty();
		});

		public SpanNearQueryDescriptor<T> Slop(int? slop) => Assign(slop, (a, v) => a.Slop = v);

		public SpanNearQueryDescriptor<T> InOrder(bool? inOrder = true) => Assign(inOrder, (a, v) => a.InOrder = v);
	}
}