arbeiten am callibration

server/server.js

@@ -937,6 +937,54 @@ app.post('/api/calibration/upload-npz', async (req, res) => {
   }
 });
 
+// ── X-Achse / Rotations-Detektion ────────────────────────────────────────────
+
+const xaxisDataDir = path.join(__dirname, '..', 'data', 'xaxis');
+const ROTATION_DETECTION_FILE = path.join(xaxisDataDir, 'rotation_detection.json');
+
+/** POST /api/xaxis/save-rotation-detection
+ *  Speichert eine Achsmessung an rotation_detection.json (append-Modus). */
+app.post('/api/xaxis/save-rotation-detection', express.json(), async (req, res) => {
+  try {
+    const { axis, runs, numMarkers, markers } = req.body ?? {};
+    if (!axis || !axis.dir || !axis.referencePoint) {
+      return res.status(400).json({ error: 'Ungültige Nutzlast: axis.dir und axis.referencePoint erwartet' });
+    }
+
+    // Verzeichnis anlegen falls nötig
+    await fsPromises.mkdir(xaxisDataDir, { recursive: true });
+
+    // Bestehende Einträge lesen oder leer beginnen
+    let entries = [];
+    try {
+      const raw = await fsPromises.readFile(ROTATION_DETECTION_FILE, 'utf-8');
+      entries = JSON.parse(raw);
+      if (!Array.isArray(entries)) entries = [];
+    } catch {
+      // Datei existiert noch nicht – kein Fehler
+    }
+
+    const newEntry = {
+      timestamp: new Date().toISOString(),
+      runs: runs ?? {},
+      axis,
+      numMarkers: numMarkers ?? null,
+      markers: markers ?? [],
+    };
+
+    entries.push(newEntry);
+    await fsPromises.writeFile(ROTATION_DETECTION_FILE, JSON.stringify(entries, null, 2), 'utf-8');
+
+    return res.json({
+      file: 'data/xaxis/rotation_detection.json',
+      total: entries.length,
+    });
+  } catch (err) {
+    console.error('save-rotation-detection error:', err);
+    return res.status(500).json({ error: String(err) });
+  }
+});
+
 async function checkServiceReachability(name, url) {
   try {
     const controller = new AbortController();