hrynco-notification-service/HrynCo.NotificationService.Services.Tests/EmailProcessing/NotificationResultPublisherTests.cs

namespace HrynCo.NotificationService.Services.Tests.EmailProcessing;

using HrynCo.NotificationService.Contracts.Messages;
using HrynCo.NotificationService.Worker.Services.EmailProcessing;
using Hrynco.RabbitMq;
using Microsoft.Extensions.Logging.Abstractions;
using NSubstitute;

public sealed class NotificationResultPublisherTests
{
    [Fact]
    public async Task PublishAsync_TerminalFailure_PublishesNeutralFailureResultToReplyQueue()
    {
        IRabbitMqPublisher rabbitMqPublisher = Substitute.For<IRabbitMqPublisher>();
        var publisher = new NotificationResultPublisher(
            rabbitMqPublisher,
            NullLogger<NotificationResultPublisher>.Instance);
        SendEmailMessage message = CreateMessage();
        NotificationResultMessage? publishedResult = null;
        rabbitMqPublisher
            .When(x => x.PublishAsync(
                "item-tracker.notifications.result",
                Arg.Any<NotificationResultMessage>(),
                Arg.Any<CancellationToken>()))
            .Do(call => publishedResult = call.ArgAt<NotificationResultMessage>(1));

        await publisher.PublishAsync(
            message,
            "Email provider could not deliver the notification.",
            CancellationToken.None);

        await rabbitMqPublisher.Received(1).PublishAsync(
            "item-tracker.notifications.result",
            Arg.Any<NotificationResultMessage>(),
            CancellationToken.None);
        Assert.NotNull(publishedResult);
        Assert.Equal(message.CorrelationContext.CorrelationId, publishedResult.CorrelationContext.CorrelationId);
        Assert.Null(publishedResult.CorrelationContext.ReplyTo);
        Assert.Equal(message.Data.ServiceName, publishedResult.Data.ServiceName);
        Assert.Equal(message.Data.TemplateKey, publishedResult.Data.TemplateKey);
        Assert.Equal(message.Data.RecipientEmail, publishedResult.Data.RecipientEmail);
        Assert.Equal("Email provider could not deliver the notification.", publishedResult.Data.ErrorMessage);
        Assert.False(publishedResult.Data.IsSuccess);
    }

    [Fact]
    public async Task PublishAsync_NoReplyQueue_DoesNotPublish()
    {
        IRabbitMqPublisher rabbitMqPublisher = Substitute.For<IRabbitMqPublisher>();
        var publisher = new NotificationResultPublisher(
            rabbitMqPublisher,
            NullLogger<NotificationResultPublisher>.Instance);
        SendEmailMessage message = CreateMessage();
        message.CorrelationContext = message.CorrelationContext with { ReplyTo = null };

        await publisher.PublishAsync(message, "delivery failed", CancellationToken.None);

        await rabbitMqPublisher.DidNotReceive()
            .PublishAsync<NotificationResultData>(
                Arg.Any<string>(),
                Arg.Any<NotificationResultMessage>(),
                Arg.Any<CancellationToken>());
    }

    [Fact]
    public async Task PublishAsync_ResultBrokerFailure_IsBestEffort()
    {
        IRabbitMqPublisher rabbitMqPublisher = Substitute.For<IRabbitMqPublisher>();
        rabbitMqPublisher
            .PublishAsync(
                Arg.Any<string>(),
                Arg.Any<NotificationResultMessage>(),
                Arg.Any<CancellationToken>())
            .Returns<Task>(_ => throw new InvalidOperationException("reply broker unavailable"));
        var publisher = new NotificationResultPublisher(
            rabbitMqPublisher,
            NullLogger<NotificationResultPublisher>.Instance);

        Exception? exception = await Record.ExceptionAsync(() => publisher.PublishAsync(
            CreateMessage(),
            "delivery failed",
            CancellationToken.None));

        Assert.Null(exception);
    }

    private static SendEmailMessage CreateMessage()
    {
        return new SendEmailMessage
        {
            CorrelationContext = new CorrelationContext
            {
                CorrelationId = "correlation-id",
                ReplyTo = "item-tracker.notifications.result"
            },
            Data = new SendEmailMessageData
            {
                ServiceName = "TestService",
                TemplateKey = "TestEmail",
                RecipientEmail = "test.user@itemtracker.local",
                RecipientName = "Test User",
                LanguageCode = "en",
                Variables = new Dictionary<string, string>()
            }
        };
    }
}