// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System;
using System.Collections.Generic;
using System.Linq;
using FluentAssertions;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Diagnostics.ExceptionSummarization;
using Microsoft.Extensions.Options;
using Microsoft.Extensions.Resilience.Internal;
using Moq;
using Polly.Telemetry;
using Xunit;
 
namespace Microsoft.Extensions.Resilience.Test.Resilience;
 
public class ResilienceServiceCollectionExtensionsTests
{
    private readonly Mock<IExceptionSummarizer> _summarizer = new(MockBehavior.Strict);
 
    private IServiceCollection _services;
 
    public ResilienceServiceCollectionExtensionsTests()
    {
        _services = new ServiceCollection().AddResilienceEnricher();
        _services.TryAddSingleton(_summarizer.Object);
    }
 
    [Fact]
    public void AddResilienceEnricher_EnsureMetricsEnricherRegistered()
    {
        var count = _services.Count;
 
        _services.AddResilienceEnricher();
 
        var enrichers = _services.BuildServiceProvider().GetRequiredService<IOptions<TelemetryOptions>>().Value.MeteringEnrichers;
        enrichers.Should().HaveCount(1);
        enrichers.Single().Should().BeOfType<ResilienceMetricsEnricher>();
    }
 
    [Fact]
    public void AddResilienceEnricher_NoExceptionSummarizer_Ok()
    {
        var services = new ServiceCollection().AddResilienceEnricher();
 
        var enrichers = services.BuildServiceProvider().GetRequiredService<IOptions<TelemetryOptions>>().Value.MeteringEnrichers;
        enrichers.Should().HaveCount(1);
        enrichers.Single().Should().BeOfType<ResilienceMetricsEnricher>();
    }
 
    [Fact]
    public void AddResilienceEnricher_Twice_NoNewServices()
    {
        var count = _services.Count;
 
        _services.AddResilienceEnricher();
 
        _services.Count.Should().Be(count);
    }
}