/* 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
*
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*  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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using System;
using System.Collections.Generic;
using System.Linq;
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.Matrix.MatrixStats
{
	public class MatrixStatsAggregationUsageTests : AggregationUsageTestBase<ReadOnlyCluster>
	{
		public MatrixStatsAggregationUsageTests(ReadOnlyCluster i, EndpointUsage usage) : base(i, usage) { }

		protected override object AggregationJson => new
		{
			matrixstats = new
			{
				meta = new
				{
					foo = "bar"
				},
				matrix_stats = new
				{
					fields = new[] { "numberOfCommits", "numberOfContributors" },
					missing = new
					{
						numberOfCommits = 0.0,
						numberOfContributors = 1.0
					},
					mode = "median"
				}
			}
		};

		protected override Func<AggregationContainerDescriptor<Project>, IAggregationContainer> FluentAggs => a => a
			.MatrixStats("matrixstats", ms => ms
				.Meta(m => m
					.Add("foo", "bar")
				)
				.Fields(fs => fs
					.Field(p => p.NumberOfCommits)
					.Field(p => p.NumberOfContributors)
				)
				.Missing(m => m
					.Add(Field<Project>(p => p.NumberOfCommits), 0)
					.Add(Field<Project>(p => p.NumberOfContributors), 1)
				)
				.Mode(MatrixStatsMode.Median)
			);

		protected override AggregationDictionary InitializerAggs =>
			new MatrixStatsAggregation("matrixstats", Field<Project>(p => p.NumberOfCommits))
			{
				Meta = new Dictionary<string, object>
				{
					{ "foo", "bar" }
				},
				Missing = new Dictionary<Field, double>
				{
					{ "numberOfCommits", 0.0 },
					{ "numberOfContributors", 1.0 },
				},
				Mode = MatrixStatsMode.Median,
				Fields = Field<Project>(p => p.NumberOfCommits).And("numberOfContributors")
			};

		protected override void ExpectResponse(ISearchResponse<Project> response)
		{
			response.ShouldBeValid();
			var matrix = response.Aggregations.MatrixStats("matrixstats");
			matrix.Should().NotBeNull();
			matrix.Fields.Should().NotBeNull().And.HaveCount(2);
			matrix.DocCount.Should().BeGreaterThan(0);

			AssertField(matrix, "numberOfCommits");
			AssertField(matrix, "numberOfContributors");
		}

		// hide
		private void AssertField(MatrixStatsAggregate aggregate, string name)
		{
			var stats = aggregate.Fields.FirstOrDefault(f => f.Name == name);
			stats.Should().NotBeNull();
			stats.Count.Should().NotBe(0);
			stats.Mean.Should().NotBe(0);
			stats.Variance.Should().NotBe(0);
			stats.Skewness.Should().NotBe(0);
			stats.Kurtosis.Should().NotBe(0);
			stats.Covariance.Should().NotBeNull().And.HaveCount(2);
			stats.Correlation.Should().NotBeNull().And.HaveCount(2);
		}
	}
}