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

namespace HrynCo.NotificationService.Services.Tests.EmailProcessing;

using HrynCo.NotificationService.Contracts.Messages;
using HrynCo.NotificationService.DAL.Abstract.Providers;
using HrynCo.NotificationService.DAL.Abstract.Repositories;
using HrynCo.NotificationService.DAL.Abstract.Templates;
using HrynCo.NotificationService.Worker.Services.EmailProcessing;
using Hrynco.RabbitMq;
using Microsoft.Extensions.Logging.Abstractions;
using NSubstitute;

public sealed class SendEmailServiceTests
{
    [Fact]
    public async Task ProcessAsync_ValidItemTrackerMessage_SendsOnceAndUpdatesUsage()
    {
        Guid channelId = Guid.NewGuid();
        var settings = new SmtpChannelSettings
        {
            Host = "smtp.example.invalid",
            Port = 587,
            Username = "smtp-user",
            Password = "not-a-real-secret",
            UseSsl = true,
            FromEmail = "notifications@example.com",
            FromName = "StoreMate"
        };
        var channel = new EmailChannel
        {
            Id = channelId,
            ServiceName = "StoreMate-Prod",
            Priority = 1,
            EmailChannelType = EmailChannelType.Smtp,
            Settings = settings,
            IsActive = true
        };
        var template = new EmailTemplate
        {
            ServiceName = "StoreMate-Prod",
            Key = "EmailVerification",
            LanguageCode = "uk",
            Subject = "Verify {{AppName}}",
            HtmlBody = "<p>{{AppName}}</p>",
            TextBody = "{{AppName}}",
            Variables = [new EmailTemplateVariable { Name = "AppName", Required = true }]
        };

        IEmailChannelRepository channels = Substitute.For<IEmailChannelRepository>();
        channels.GetByServiceAsync("StoreMate-Prod", Arg.Any<CancellationToken>())
            .Returns([channel]);
        IEmailChannelUsageRepository usage = Substitute.For<IEmailChannelUsageRepository>();
        IEmailTemplateService templates = Substitute.For<IEmailTemplateService>();
        templates.GetAsync("StoreMate-Prod", "EmailVerification", "uk", Arg.Any<CancellationToken>())
            .Returns(template);
        var renderer = new EmailTemplateRenderingService();
        var smtp = new RecordingSmtpEmailSender();
        INotificationResultPublisher resultPublisher = Substitute.For<INotificationResultPublisher>();
        var service = new SendEmailService(
            channels,
            usage,
            templates,
            renderer,
            smtp,
            resultPublisher,
            NullLogger<SendEmailService>.Instance);
        var message = new SendEmailMessage
        {
            CorrelationContext = new CorrelationContext
            {
                CorrelationId = Guid.NewGuid().ToString("D")
            },
            Data = new SendEmailMessageData
            {
                ServiceName = "StoreMate-Prod",
                TemplateKey = "EmailVerification",
                RecipientEmail = "owner@example.com",
                RecipientName = "Owner",
                LanguageCode = "uk",
                Variables = new Dictionary<string, string> { ["AppName"] = "StoreMate" }
            }
        };

        await service.ProcessAsync(message, CancellationToken.None);

        Assert.Equal(1, smtp.SendCount);
        Assert.Same(settings, smtp.Settings);
        Assert.Equal("Verify StoreMate", smtp.Email?.Subject);
        Assert.Equal("owner@example.com", smtp.RecipientEmail);
        Assert.Equal("Owner", smtp.RecipientName);
        await usage.Received(1).IncrementUsageAsync(
            channelId,
            Arg.Any<DateOnly>(),
            CancellationToken.None);
        await resultPublisher.Received(1).PublishAsync(
            message,
            null,
            CancellationToken.None);
    }

    private sealed class RecordingSmtpEmailSender : ISmtpEmailSender
    {
        public int SendCount { get; private set; }
        public SmtpChannelSettings? Settings { get; private set; }
        public RenderedEmail? Email { get; private set; }
        public string? RecipientEmail { get; private set; }
        public string? RecipientName { get; private set; }

        public Task SendAsync(
            SmtpChannelSettings settings,
            RenderedEmail email,
            string recipientEmail,
            string recipientName,
            CancellationToken cancellationToken)
        {
            SendCount++;
            Settings = settings;
            Email = email;
            RecipientEmail = recipientEmail;
            RecipientName = recipientName;
            return Task.CompletedTask;
        }
    }
}