Fix: Remote Desktop — 60fps, Screen-Wechsel live, Consent-Dialog sichtbar (v2.3.0)

- CaptureModeRunner: Thread.Sleep(150) → 16ms (~60fps) + Skip-if-unchanged via Pixel-Hash
- RtcService: rdp_switch_screen Handler — Screen wechseln ohne Consent-Dialog
- RtcService: Fallback bei Consent-Fehler → rdp_denied statt silent capture
- RdpConsentWindow: WindowStyle=ToolWindow + ShowInTaskbar=True (jetzt in Taskleiste sichtbar)
- RemoteDesktopPanel: Screen-Dropdown auch während aktiver Verbindung nutzbar
- Version: 2.2.0 → 2.3.0

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

agent-cs/AgentWorker.cs

@@ -6,7 +6,7 @@ namespace ITNexusAgent;
 
 public class AgentWorker
 {
-    private const string Version = "2.2.0";
+    private const string Version = "2.3.0";
     private const string DataDir = @"C:\ProgramData\IT Nexus Agent";
     private const string ConfigPath = @"C:\ProgramData\IT Nexus Agent\config.json";
     private const string StatusPath = @"C:\ProgramData\IT Nexus Agent\status.json";

agent-cs/CaptureModeRunner.cs

@@ -24,7 +24,6 @@ public static class CaptureModeRunner
             var encParams = new EncoderParameters(1);
             encParams.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 60L);
 
-            // Capture-Region bestimmen: 0 = alle Screens, 1-N = spezifischer Screen
             var allScreens = System.Windows.Forms.Screen.AllScreens;
             Rectangle captureRect;
             if (screenIdx <= 0 || screenIdx > allScreens.Length)
@@ -40,14 +39,27 @@ public static class CaptureModeRunner
                 captureRect = allScreens[screenIdx - 1].Bounds;
             }
 
+            uint lastHash = 0;
+            var sw = System.Diagnostics.Stopwatch.StartNew();
+
             while (tcp.Connected)
             {
+                sw.Restart();
                 try
                 {
                     using var bmp = new Bitmap(captureRect.Width, captureRect.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
                     using (var g = Graphics.FromImage(bmp))
                         g.CopyFromScreen(captureRect.X, captureRect.Y, 0, 0, new Size(captureRect.Width, captureRect.Height));
 
+                    var hash = SampleHash(bmp);
+                    if (hash == lastHash)
+                    {
+                        var elapsed = (int)sw.ElapsedMilliseconds;
+                        if (elapsed < 16) Thread.Sleep(16 - elapsed);
+                        continue;
+                    }
+                    lastHash = hash;
+
                     byte[] jpeg;
                     using (var ms = new MemoryStream())
                     {
@@ -55,16 +67,32 @@ public static class CaptureModeRunner
                         jpeg = ms.ToArray();
                     }
 
-                    // 4-Byte Länge (LE) + JPEG-Daten
                     stream.Write(BitConverter.GetBytes(jpeg.Length));
                     stream.Write(jpeg);
                     stream.Flush();
                 }
                 catch { break; }
 
-                Thread.Sleep(150); // ~6-7 fps
+                var frameMs = (int)sw.ElapsedMilliseconds;
+                if (frameMs < 16) Thread.Sleep(16 - frameMs); // cap at ~60 fps
             }
         }
         catch { /* Verbindung fehlgeschlagen → Exit */ }
     }
+
+    private static uint SampleHash(Bitmap bmp)
+    {
+        // Sample 64 evenly-distributed pixels — fast change detection, O(1)
+        uint h = 2166136261u;
+        int w = bmp.Width, ht = bmp.Height;
+        int stepX = Math.Max(1, w / 8);
+        int stepY = Math.Max(1, ht / 8);
+        for (int y = 0; y < ht; y += stepY)
+            for (int x = 0; x < w; x += stepX)
+            {
+                var c = bmp.GetPixel(x, y);
+                h = (h ^ (uint)c.ToArgb()) * 16777619u;
+            }
+        return h;
+    }
 }

agent-cs/IT-Nexus-Agent.csproj

@@ -7,8 +7,8 @@
     <UseWindowsForms>true</UseWindowsForms>
     <AssemblyName>IT-Nexus-Agent</AssemblyName>
     <RootNamespace>ITNexusAgent</RootNamespace>
-    <Version>2.0.0</Version>
+    <Version>2.3.0</Version>
-    <AssemblyVersion>2.0.0.0</AssemblyVersion>
+    <AssemblyVersion>2.3.0.0</AssemblyVersion>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
     <AllowUnsafeBlocks>false</AllowUnsafeBlocks>

agent-cs/Services/RtcService.cs

@@ -70,6 +70,15 @@ public class RtcService
                 _ = ConsentAndCaptureAsync(ws, screenIdx, captureCts.Token);
                 AgentWorker.Log($"RDP: Consent angefordert (screen={screenIdx})");
             }
+            else if (type == "rdp_switch_screen" && captureCts != null)
+            {
+                // Consent bereits erteilt — nur Screen wechseln, kein erneuter Dialog
+                var newScreen = obj["screen"]?.ToObject<int>() ?? 0;
+                captureCts.Cancel();
+                captureCts = CancellationTokenSource.CreateLinkedTokenSource(ct);
+                _ = CapturePipeLoopAsync(ws, newScreen, captureCts.Token);
+                AgentWorker.Log($"RDP: Screen gewechselt zu {newScreen}");
+            }
             else if (type == "rdp_stop" && captureCts != null)
             {
                 captureCts.Cancel();
@@ -93,8 +102,10 @@ public class RtcService
         if (!SpawnConsentHelper(exePath, consentPort.ToString()))
         {
             consentListener.Stop();
-            AgentWorker.Log("RDP: Consent-Helper fehlgeschlagen, starte ohne Consent");
+            AgentWorker.Log("RDP: Consent-Helper fehlgeschlagen, verweigere Zugriff");
-            await CapturePipeLoopAsync(ws, screenIdx, ct);
+            var failed = Encoding.UTF8.GetBytes("{\"type\":\"rdp_denied\",\"reason\":\"consent_spawn_failed\"}");
+            if (ws.State == WebSocketState.Open)
+                await ws.SendAsync(new ArraySegment<byte>(failed), WebSocketMessageType.Text, true, CancellationToken.None);
             return;
         }
 

agent-cs/Services/ShellService.cs

@@ -40,7 +40,7 @@ public class ShellService
             + $"/ws?type=agent&key={Uri.EscapeDataString(_agentKey)}&hostname={Uri.EscapeDataString(_hostname)}";
 
         using var ws = new ClientWebSocket();
-        ws.Options.SetRequestHeader("User-Agent", "IT-Nexus-Agent/2.1.2");
+        ws.Options.SetRequestHeader("User-Agent", "IT-Nexus-Agent/2.3.0");
 
         await ws.ConnectAsync(new Uri(wsUrl), ct);
         AgentWorker.Log("SHELL: WebSocket verbunden");

agent-cs/UI/RdpConsentWindow.xaml

@@ -1,15 +1,16 @@
 <Window x:Class="ITNexusAgent.UI.RdpConsentWindow"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        Title="IT Nexus – Bildschirmzugriff"
+        Title="IT Nexus – Bildschirmzugriff angefordert"
         Width="480" Height="Auto"
         SizeToContent="Height"
         WindowStartupLocation="CenterScreen"
         ResizeMode="NoResize"
-        WindowStyle="None"
+        WindowStyle="ToolWindow"
         AllowsTransparency="False"
         Background="#1A1D2E"
         Topmost="True"
+        ShowInTaskbar="True"
         FontFamily="Segoe UI">
 
     <Window.Resources>

agent-cs/setup.iss

@@ -1,5 +1,5 @@
 #define MyAppName "IT Nexus Agent"
-#define MyAppVersion "2.2.0"
+#define MyAppVersion "2.3.0"
 #define MyAppPublisher "Cereda Systems GmbH"
 #define MyAppURL "https://it-nexus.cereda-systems.de"
 #define MyAppExeName "IT-Nexus-Agent.exe"

frontend/src/components/common/RemoteDesktopPanel.jsx

@@ -61,7 +61,9 @@ export default function RemoteDesktopPanel({ agentId, agentHostname, autoConnect
                     img.src = 'data:image/jpeg;base64,' + msg.data;
                 } else if (msg.type === 'rdp_denied') {
                     setStatus('error');
-                    setError('Zugriff wurde vom Benutzer abgelehnt');
+                    setError(msg.reason === 'consent_spawn_failed'
+                        ? 'Consent-Dialog konnte nicht geöffnet werden (schtasks-Fehler)'
+                        : 'Zugriff wurde vom Benutzer abgelehnt');
                     ws.close();
                 } else if (msg.type === 'rdp_disconnected') {
                     setStatus('idle');
@@ -119,8 +121,14 @@ export default function RemoteDesktopPanel({ agentId, agentHostname, autoConnect
                 {/* Screen-Selektor */}
                 <select
                     value={screenIdx}
-                    onChange={e => setScreenIdx(Number(e.target.value))}
+                    onChange={e => {
-                    disabled={status === 'connected' || status === 'connecting' || status === 'waiting'}
+                        const newIdx = Number(e.target.value);
+                        setScreenIdx(newIdx);
+                        if (status === 'connected' && wsRef.current?.readyState === WebSocket.OPEN) {
+                            wsRef.current.send(JSON.stringify({ type: 'rdp_switch_screen', screen: newIdx }));
+                        }
+                    }}
+                    disabled={status === 'connecting' || status === 'waiting'}
                     style={{ fontSize: 12, padding: '3px 8px', borderRadius: 7, border: '1px solid var(--border-color)', background: 'var(--bg-tertiary)', color: 'var(--text-primary)', cursor: 'pointer', marginLeft: 4 }}
                 >
                     {SCREEN_OPTIONS.map(o => (

frontend/src/pages/PatchManagementPage.jsx

@@ -5,7 +5,7 @@ import { useAuth } from '../context/AuthContext';
 
 const ANN_TYPES = { maintenance: { icon: '🔧', label: 'Wartung', color: '#f59e0b' }, warning: { icon: '⚠️', label: 'Warnung', color: '#ef4444' }, info: { icon: 'ℹ️', label: 'Info', color: '#6366f1' } };
 
-const LATEST_AGENT_VERSION = '2.2.0';
+const LATEST_AGENT_VERSION = '2.3.0';
 const SEVERITY_LABELS = { critical: 'Kritisch', important: 'Wichtig', moderate: 'Moderat', low: 'Niedrig', all: 'Alle' };
 const SEVERITY_COLORS = { critical: '#EF4444', important: '#F59E0B', moderate: '#3B82F6', low: '#6B7280', all: '#0D9488' };
 const COMMAND_LABELS = { check_updates: '🔍 Update-Scan', install_updates: '⬇️ Installation', reboot: '🔄 Neustart', upgrade_win11: '🪟 Win 11 Upgrade', update_agent: '⬆️ Agent-Update' };