[eric] onboarding flow, user ui/ux

frontend/src/shared/analytics.ts

@@ -0,0 +1,26 @@
+import { API_BASE } from './config';
+
+let _lastAction = '';
+let _lastPage = '';
+let _appStartTime = Date.now();
+
+export function trackEvent(eventType: string, properties?: Record<string, any>, useBeacon = false) {
+  _lastAction = eventType;
+  _lastPage = window.location.hash || window.location.pathname;
+
+  const body = JSON.stringify({ event_type: eventType, properties });
+  if (useBeacon && navigator.sendBeacon) {
+    // sendBeacon is guaranteed to complete even during page unload
+    navigator.sendBeacon(`${API_BASE}/analytics/event`, new Blob([body], { type: 'application/json' }));
+  } else {
+    fetch(`${API_BASE}/analytics/event`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body,
+    }).catch(() => {});
+  }
+}
+
+export function getLastAction() { return _lastAction; }
+export function getLastPage() { return _lastPage; }
+export function getTimeSpent() { return Math.round((Date.now() - _appStartTime) / 1000); }