Update src/security/anomalyEngine.js

src/security/anomalyEngine.js

@@ -1,13 +1,23 @@
-import IsolationForest from "ml-isolation-forest";
+let stats = {
+  mean: 0,
+  std: 1,
+};
 
-let model = null;
+export function trainModel(values) {
+  const n = values.length;
+  if (n === 0) return;
 
-export function trainModel(data) {
-  model = new IsolationForest({ contamination: 0.02 });
-  model.fit(data);
+  const mean = values.reduce((a, b) => a + b, 0) / n;
+  const variance =
+    values.reduce((a, b) => a + (b - mean) ** 2, 0) / n;
+
+  stats.mean = mean;
+  stats.std = Math.sqrt(variance) || 1;
+
+  console.log("📊 Anomaly model trained", stats);
 }
 
-export function isAnomaly(vec) {
-  if (!model) return false;
-  return model.predict([vec])[0] === -1;
+export function isAnomaly(value) {
+  const z = Math.abs((value - stats.mean) / stats.std);
+  return z > 3; // Z-score threshold
 }