New signals

Directory.Packages.props

@@ -63,6 +63,10 @@
          NuGetAudit + TreatWarningsAsErrors the advisory also fails restore, so
          staying on 2025.1.0 is not an option anyway. -->
     <PackageVersion Include="SSH.NET" Version="2026.0.0" />
+    <!-- E-mail action for camera events (SMTP transport). MailKit rather than
+         System.Net.Mail: the latter cannot do implicit TLS on port 465, which
+         Mail.ru / Yandex and many corporate relays expect. -->
+    <PackageVersion Include="MailKit" Version="4.18.1" />
     <!-- Avalonia.Skia 12.0.3 pulls SkiaSharp 3.119.4-preview.1.1 transitively; match it explicitly. -->
     <PackageVersion Include="SkiaSharp" Version="3.119.4-preview.1.1" />
     <!-- Linux native libSkiaSharp for the Avalonia-less test process. The

README.md

@@ -65,8 +65,14 @@ Built with .NET 9 / 10 and Avalonia 12.
   snapshots over SSH.
 - **Health & status** — unified per-camera verdict (online / attention /
   offline) across grid, library and a Health Center overview.
-- **Notifications** — system notifications for motion and detections, with
-  quiet hours.
+- **Notifications** — alerts for motion and detections with thresholds (AI
+  confidence, event duration, objects in frame), cooldown and quiet hours.
+  Desktop: the app's own toast with a built-in or custom sound and volume, or
+  native Windows notifications managed in Windows Settings.
+- **External actions** — react to an event outside the app: a TCP/UDP signal
+  (text or raw hex) to an alarm panel or relay, an HTTP webhook, an e-mail
+  (SMTP with the login kept in Windows Credential Manager, the default mail
+  client via MAPI, or Outlook), or a local program/script.
 - **Desktop niceties** — tray icon with quick actions, optional
   close-to-tray, choice of start page (Library or Live) and startup layout,
   light/dark themes with accent colors.

src/OpenIPC.Viewer.App/Services/DesktopNotificationService.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
@@ -7,27 +8,58 @@
 
 namespace OpenIPC.Viewer.App.Services;
 
-// Desktop notification sink (Phase 19.3): stacks Telegram-style toast windows in
-// the bottom-right of the primary screen. The coordinator already vetted the
-// notification (cooldown / quiet hours / type) — we just present it. Marshals to
-// the UI thread since events arrive off the decode/event pipeline.
+// Desktop notification sink (Phase 19.3). The coordinator already vetted the
+// notification (thresholds / cooldown / quiet hours / type); this decides how it
+// looks and sounds, per the "Notification style" setting:
+//   "app"     — Telegram-style toast windows stacked bottom-right of the primary
+//               screen, plus the app's own sound at the chosen volume;
+//   "windows" — a native Windows toast (ISystemNotificationSink); banners, sound
+//               and Do Not Disturb are then governed by Windows Settings.
+// Marshals to the UI thread since events arrive off the decode/event pipeline.
 public sealed class DesktopNotificationService : INotificationService
 {
+    public const string StyleApp = "app";
+    public const string StyleWindows = "windows";
+
     // Newest at the bottom; older ones float up. Cap so a burst doesn't paper
     // over the whole screen — the oldest is dropped when the cap is hit.
     private const int MaxVisible = 4;
     private const double MarginDip = 16;
     private const double GapDip = 10;
 
+    private readonly UserSettingsService _settings;
+    private readonly NotificationSoundService _sound;
+    private readonly ISystemNotificationSink? _system;
     private readonly List<ToastWindow> _active = new();
 
+    public DesktopNotificationService(
+        UserSettingsService settings,
+        NotificationSoundService sound,
+        ISystemNotificationSink? system = null)
+    {
+        _settings = settings;
+        _sound = sound;
+        _system = system;
+    }
+
     // Always available on desktop — this sink is only registered in the desktop
     // head. (We can't probe Application.Current here: the coordinator is Start()ed
     // during composition, before the Avalonia lifetime exists.)
     public bool IsAvailable => true;
 
+    public bool UsesSystemNotifications =>
+        _system is { IsSupported: true } &&
+        string.Equals(_settings.Current.NotificationStyle, StyleWindows, StringComparison.OrdinalIgnoreCase);
+
     public void Show(NotificationRequest request)
     {
+        if (UsesSystemNotifications)
+        {
+            _system!.Show(request);
+            return;
+        }
+
+        _sound.PlayForNotification();
         if (Dispatcher.UIThread.CheckAccess()) ShowCore(request);
         else Dispatcher.UIThread.Post(() => ShowCore(request));
     }

src/OpenIPC.Viewer.App/Services/ISystemNotificationSink.cs

@@ -0,0 +1,31 @@
+using OpenIPC.Viewer.Core.Notifications;
+
+namespace OpenIPC.Viewer.App.Services;
+
+// The operating system's own notification center as an alternative to the
+// app's corner toast (desktop "Notification style" setting). Today that is the
+// Windows Action Center: the app shows up in Settings → System → Notifications,
+// where the user controls banners, sound, priority and Do Not Disturb with the
+// standard Windows tools. Registered by the Windows head only.
+public interface ISystemNotificationSink
+{
+    // False on systems without native toasts (e.g. before Windows 10).
+    bool IsSupported { get; }
+
+    // Whether Windows will actually display our toasts right now.
+    SystemNotificationState State { get; }
+
+    void Show(NotificationRequest request);
+
+    // Opens the OS notification settings page.
+    void OpenSettings();
+}
+
+public enum SystemNotificationState
+{
+    Enabled,
+    DisabledForApp,
+    DisabledForUser,
+    DisabledByPolicy,
+    Unavailable,
+}