feat(notification-outbox): add Email notification delivery adapter

tests/ScadaLink.NotificationOutbox.Tests/Delivery/EmailNotificationDeliveryAdapterTests.cs

@@ -0,0 +1,191 @@
+using System.Net.Sockets;
+using MailKit;
+using MailKit.Net.Smtp;
+using Microsoft.Extensions.Logging.Abstractions;
+using NSubstitute;
+using NSubstitute.ExceptionExtensions;
+using ScadaLink.Commons.Entities.Notifications;
+using ScadaLink.Commons.Interfaces.Repositories;
+using ScadaLink.Commons.Types.Enums;
+using ScadaLink.NotificationOutbox.Delivery;
+using ScadaLink.NotificationService;
+
+namespace ScadaLink.NotificationOutbox.Tests.Delivery;
+
+/// <summary>
+/// Task 12: Tests for the Email outbox delivery adapter — list/recipient/SMTP-config
+/// resolution, SMTP send, and the three-way (Success / Permanent / Transient) outcome
+/// classification.
+/// </summary>
+public class EmailNotificationDeliveryAdapterTests
+{
+    private readonly INotificationRepository _repository = Substitute.For<INotificationRepository>();
+    private readonly ISmtpClientWrapper _smtpClient = Substitute.For<ISmtpClientWrapper>();
+
+    private EmailNotificationDeliveryAdapter CreateAdapter()
+    {
+        return new EmailNotificationDeliveryAdapter(
+            _repository,
+            () => _smtpClient,
+            NullLogger<EmailNotificationDeliveryAdapter>.Instance);
+    }
+
+    private static Notification MakeNotification(string listName = "ops-team")
+    {
+        return new Notification(
+            Guid.NewGuid().ToString(),
+            NotificationType.Email,
+            listName,
+            "Subject",
+            "Body",
+            "site-1");
+    }
+
+    private void SetupHappyPath()
+    {
+        var list = new NotificationList("ops-team") { Id = 1 };
+        var recipients = new List<NotificationRecipient>
+        {
+            new("Alice", "alice@example.com") { Id = 1, NotificationListId = 1 },
+            new("Bob", "bob@example.com") { Id = 2, NotificationListId = 1 }
+        };
+        var smtpConfig = new SmtpConfiguration("smtp.example.com", "basic", "noreply@example.com")
+        {
+            Id = 1, Port = 587, Credentials = "user:pass", TlsMode = "starttls"
+        };
+
+        _repository.GetListByNameAsync("ops-team").Returns(list);
+        _repository.GetRecipientsByListIdAsync(1).Returns(recipients);
+        _repository.GetAllSmtpConfigurationsAsync().Returns(new List<SmtpConfiguration> { smtpConfig });
+    }
+
+    [Fact]
+    public void Type_IsEmail()
+    {
+        Assert.Equal(NotificationType.Email, CreateAdapter().Type);
+    }
+
+    [Fact]
+    public async Task Deliver_HappyPath_ReturnsSuccessWithResolvedTargets()
+    {
+        SetupHappyPath();
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.Success, outcome.Result);
+        Assert.NotNull(outcome.ResolvedTargets);
+        Assert.Contains("alice@example.com", outcome.ResolvedTargets);
+        Assert.Contains("bob@example.com", outcome.ResolvedTargets);
+        Assert.Null(outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_ListNotFound_ReturnsPermanent()
+    {
+        _repository.GetListByNameAsync("missing").Returns((NotificationList?)null);
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification("missing"));
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.Contains("missing", outcome.Error);
+        Assert.Contains("not found", outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_NoRecipients_ReturnsPermanent()
+    {
+        var list = new NotificationList("ops-team") { Id = 1 };
+        _repository.GetListByNameAsync("ops-team").Returns(list);
+        _repository.GetRecipientsByListIdAsync(1).Returns(new List<NotificationRecipient>());
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.Contains("recipient", outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_NoSmtpConfig_ReturnsPermanent()
+    {
+        var list = new NotificationList("ops-team") { Id = 1 };
+        _repository.GetListByNameAsync("ops-team").Returns(list);
+        _repository.GetRecipientsByListIdAsync(1).Returns(new List<NotificationRecipient>
+        {
+            new("Alice", "alice@example.com") { Id = 1, NotificationListId = 1 }
+        });
+        _repository.GetAllSmtpConfigurationsAsync().Returns(new List<SmtpConfiguration>());
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.Contains("SMTP", outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_SmtpPermanentException_ReturnsPermanent()
+    {
+        SetupHappyPath();
+        _smtpClient
+            .SendAsync(Arg.Any<string>(), Arg.Any<IEnumerable<string>>(),
+                Arg.Any<string>(), Arg.Any<string>(), Arg.Any<CancellationToken>())
+            .ThrowsAsync(new SmtpPermanentException("550 mailbox unavailable"));
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.Contains("mailbox unavailable", outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_Smtp5xxCommandException_ReturnsPermanent()
+    {
+        SetupHappyPath();
+        _smtpClient
+            .SendAsync(Arg.Any<string>(), Arg.Any<IEnumerable<string>>(),
+                Arg.Any<string>(), Arg.Any<string>(), Arg.Any<CancellationToken>())
+            .ThrowsAsync(new SmtpCommandException(
+                SmtpErrorCode.RecipientNotAccepted, SmtpStatusCode.MailboxUnavailable, "rejected"));
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+    }
+
+    [Fact]
+    public async Task Deliver_SocketException_ReturnsTransient()
+    {
+        SetupHappyPath();
+        _smtpClient
+            .ConnectAsync(Arg.Any<string>(), Arg.Any<int>(), Arg.Any<SmtpTlsMode>(),
+                Arg.Any<int>(), Arg.Any<CancellationToken>())
+            .ThrowsAsync(new SocketException((int)SocketError.ConnectionRefused));
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.TransientFailure, outcome.Result);
+        Assert.NotNull(outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_Smtp4xxCommandException_ReturnsTransient()
+    {
+        SetupHappyPath();
+        _smtpClient
+            .SendAsync(Arg.Any<string>(), Arg.Any<IEnumerable<string>>(),
+                Arg.Any<string>(), Arg.Any<string>(), Arg.Any<CancellationToken>())
+            .ThrowsAsync(new SmtpCommandException(
+                SmtpErrorCode.MessageNotAccepted, SmtpStatusCode.MailboxBusy, "try later"));
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.TransientFailure, outcome.Result);
+    }
+}