/* 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 FluentAssertions;
using OpenSearch.Client;
using Tests.Core.Extensions;
using Tests.Core.ManagedOpenSearch.Clusters;
using Tests.Domain;
using Tests.Framework.EndpointTests.TestState;
using static OpenSearch.Client.Infer;

namespace Tests.Aggregations.Bucket.ReverseNested
{
	public class ReverseNestedAggregationUsageTests : AggregationUsageTestBase<ReadOnlyCluster>
	{
		public ReverseNestedAggregationUsageTests(ReadOnlyCluster i, EndpointUsage usage) : base(i, usage) { }

		protected override object AggregationJson => new
		{
			tags = new
			{
				nested = new { path = "tags", },
				aggs = new
				{
					tag_names = new
					{
						terms = new { field = "tags.name" },
						aggs = new
						{
							tags_to_project = new
							{
								reverse_nested = new { },
								aggs = new
								{
									top_projects_per_tag = new
									{
										terms = new { field = "name" }
									}
								}
							}
						}
					}
				}
			}
		};

		protected override Func<AggregationContainerDescriptor<Project>, IAggregationContainer> FluentAggs => a => a
			.Nested("tags", n => n
				.Path(p => p.Tags)
				.Aggregations(aa => aa
					.Terms("tag_names", t => t
						.Field(p => p.Tags.Suffix("name"))
						.Aggregations(aaa => aaa
							.ReverseNested("tags_to_project", r => r
								.Aggregations(aaaa => aaaa
									.Terms("top_projects_per_tag", tt => tt
										.Field(p => p.Name)
									)
								)
							)
						)
					)
				)
			);

		protected override AggregationDictionary InitializerAggs =>
			new NestedAggregation("tags")
			{
				Path = "tags",
				Aggregations = new TermsAggregation("tag_names")
				{
					Field = "tags.name",
					Aggregations = new ReverseNestedAggregation("tags_to_project")
					{
						Aggregations = new TermsAggregation("top_projects_per_tag")
						{
							Field = Field<Project>(p => p.Name)
						}
					}
				}
			};

		protected override void ExpectResponse(ISearchResponse<Project> response)
		{
			response.ShouldBeValid();
			var tags = response.Aggregations.Nested("tags");
			tags.Should().NotBeNull();
			var tagNames = tags.Terms("tag_names");
			tagNames.Should().NotBeNull();
			foreach (var tagName in tagNames.Buckets)
			{
				tagName.Key.Should().NotBeNullOrEmpty();
				tagName.DocCount.Should().BeGreaterThan(0);
				var tagsToProjects = tagName.ReverseNested("tags_to_project");
				tagsToProjects.Should().NotBeNull();
				var topProjectsPerTag = tagsToProjects.Terms("top_projects_per_tag");
				topProjectsPerTag.Should().NotBeNull();
				foreach (var topProject in topProjectsPerTag.Buckets)
				{
					topProject.Key.Should().NotBeNullOrEmpty();
					topProject.DocCount.Should().BeGreaterThan(0);
				}
			}
		}
	}
}