feat: добавил отправку уведомлений по почте

backend/UniVerse.Infrastructure/Notifications/NotificationService.cs

@@ -0,0 +1,49 @@
+using Microsoft.Extensions.Logging;
+using UniVerse.Application.DTOs.Notifications;
+using UniVerse.Application.Interfaces;
+
+namespace UniVerse.Infrastructure.Notifications;
+
+public class NotificationService : INotificationService
+{
+    private readonly IEnumerable<INotificationProvider> _providers;
+    private readonly INotificationScheduler _scheduler;
+    private readonly ILogger<NotificationService> _logger;
+
+    public NotificationService(
+        IEnumerable<INotificationProvider> providers,
+        INotificationScheduler scheduler,
+        ILogger<NotificationService> logger)
+    {
+        _providers = providers;
+        _scheduler = scheduler;
+        _logger = logger;
+    }
+
+    public async Task SendAsync(NotificationMessage message, CancellationToken cancellationToken = default)
+    {
+        ArgumentException.ThrowIfNullOrWhiteSpace(message.Channel);
+        ArgumentException.ThrowIfNullOrWhiteSpace(message.Recipient);
+        ArgumentException.ThrowIfNullOrWhiteSpace(message.Subject);
+        ArgumentException.ThrowIfNullOrWhiteSpace(message.Body);
+
+        var provider = _providers.FirstOrDefault(p => string.Equals(p.Channel, message.Channel, StringComparison.OrdinalIgnoreCase))
+            ?? throw new InvalidOperationException($"Notification provider for channel '{message.Channel}' is not registered.");
+
+        _logger.LogInformation("Dispatching notification through {Channel} to {Recipient}", message.Channel, message.Recipient);
+        await provider.SendAsync(message, cancellationToken);
+    }
+
+    public Task<ScheduledNotificationResponse> ScheduleAsync(ScheduleNotificationRequest request, CancellationToken cancellationToken = default)
+    {
+        var message = new NotificationMessage(
+            request.Channel,
+            request.Recipient,
+            request.Subject,
+            request.Body,
+            request.RecipientName,
+            request.Metadata);
+
+        return _scheduler.ScheduleAsync(message, request.SendAt, cancellationToken);
+    }
+}