feat: integrate WebSocket with live tracking

- Add WebSocket state variables (wsEnabled, wsConnected)
- Add initWebSocket() function with connection and event handling
- Add handleWebSocketScanUpdate() for processing WS scan events
- Modify startLiveTracking() to use WS mode with HTTP fallback
- Update index.html to load socket.io and websocket.js scripts
- Show [WS] indicator in status when using WebSocket mode

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/rf_mapper/web/static/js/app.js

@@ -33,6 +33,10 @@ let liveTrackingEnabled = false;
 let liveTrackingInterval = null;
 const LIVE_TRACKING_INTERVAL_MS = 4000; // 4 seconds
 
+// WebSocket state
+let wsEnabled = true;  // Try WebSocket first
+let wsConnected = false;
+
 // Statistical movement detection
 const SAMPLE_HISTORY_SIZE = 5;  // Number of samples to keep for averaging
 const MOVEMENT_THRESHOLD = 1.5; // meters - movement must exceed this + stddev margin
@@ -134,6 +138,9 @@ document.addEventListener('DOMContentLoaded', () => {
         map3dInitialized = true;
     }, 100);
 
+    // Initialize WebSocket connection
+    initWebSocket();
+
     // Start BT live tracking by default after a short delay
     setTimeout(() => {
         startLiveTracking();
@@ -141,6 +148,152 @@ document.addEventListener('DOMContentLoaded', () => {
     }, 2000);
 });
 
+// Initialize WebSocket connection for real-time updates
+function initWebSocket() {
+    if (!wsEnabled) return;
+
+    // Check if rfMapperWS is available (websocket.js loaded)
+    if (typeof rfMapperWS === 'undefined') {
+        console.log('[App] WebSocket module not loaded, using HTTP polling');
+        return;
+    }
+
+    const connected = rfMapperWS.connect();
+    if (!connected) {
+        console.log('[App] WebSocket not available, using HTTP polling');
+        return;
+    }
+
+    rfMapperWS.on('connected', () => {
+        wsConnected = true;
+        console.log('[App] WebSocket connected');
+
+        // Stop HTTP polling if running (WS will handle updates)
+        if (liveTrackingInterval) {
+            clearInterval(liveTrackingInterval);
+            liveTrackingInterval = null;
+            console.log('[App] Stopped HTTP polling (using WebSocket)');
+        }
+    });
+
+    rfMapperWS.on('disconnected', (data) => {
+        wsConnected = false;
+        console.log('[App] WebSocket disconnected:', data?.reason);
+
+        // Resume HTTP polling if live tracking is enabled
+        if (liveTrackingEnabled && !liveTrackingInterval) {
+            liveTrackingInterval = setInterval(performLiveBTScan, LIVE_TRACKING_INTERVAL_MS);
+            console.log('[App] Resumed HTTP polling');
+        }
+    });
+
+    rfMapperWS.on('scanUpdate', (data) => {
+        handleWebSocketScanUpdate(data);
+    });
+}
+
+// Handle scan updates received via WebSocket
+function handleWebSocketScanUpdate(data) {
+    if (!liveTrackingEnabled) return;
+
+    console.log('[WS] Scan update:', data.type, data.devices?.length, 'devices');
+
+    // Handle Bluetooth scan results
+    if (data.type === 'bluetooth' && data.devices) {
+        const newBt = data.devices;
+
+        // Track which devices were detected in this scan
+        const detectedAddresses = new Set(newBt.map(d => d.address));
+
+        if (scanData) {
+            const existingBt = scanData.bluetooth_devices || [];
+
+            // Update existing devices with new RSSI, add new devices
+            newBt.forEach(newDev => {
+                const existing = existingBt.find(d => d.address === newDev.address);
+                const newDist = newDev.estimated_distance_m;
+
+                // Check for movement using statistical analysis
+                const moving = isDeviceMoving(newDev.address, newDist);
+
+                // Reset miss count - device was detected
+                deviceMissCount[newDev.address] = 0;
+
+                if (existing) {
+                    // Update RSSI and estimated distance, preserve custom values
+                    existing.rssi = newDev.rssi;
+                    existing.estimated_distance_m = newDev.estimated_distance_m;
+                    existing.signal_quality = newDev.signal_quality;
+                    existing.is_moving = moving;
+                    existing.miss_count = 0;
+                    // Preserve floor and custom_distance_m if set
+                } else {
+                    // New device, add it
+                    newDev.is_moving = moving;
+                    existingBt.push(newDev);
+                }
+            });
+
+            // Increment miss count for devices not detected in this scan
+            existingBt.forEach(dev => {
+                if (!detectedAddresses.has(dev.address)) {
+                    deviceMissCount[dev.address] = (deviceMissCount[dev.address] || 0) + 1;
+                    dev.miss_count = deviceMissCount[dev.address];
+                }
+            });
+
+            // Filter out devices that have been missed too many times
+            const filteredBt = existingBt.filter(dev => {
+                const missCount = deviceMissCount[dev.address] || 0;
+                if (missCount >= MAX_MISSED_SCANS) {
+                    // Clean up tracking data for removed device
+                    delete deviceMissCount[dev.address];
+                    delete deviceDistanceHistory[dev.address];
+                    // Clear trail if showing
+                    if (deviceTrails[dev.address]) {
+                        clearDeviceTrail(dev.address);
+                    }
+                    console.log(`[WS] Removed ${dev.name} (missed ${missCount} scans)`);
+                    return false;
+                }
+                return true;
+            });
+
+            scanData.bluetooth_devices = filteredBt;
+        } else {
+            // No existing scan data, use BT-only data
+            newBt.forEach(dev => {
+                // Initialize history with first sample, not moving yet
+                isDeviceMoving(dev.address, dev.estimated_distance_m);
+                dev.is_moving = false;
+                deviceMissCount[dev.address] = 0;
+            });
+            scanData = {
+                wifi_networks: [],
+                bluetooth_devices: newBt,
+                timestamp: data.timestamp
+            };
+        }
+
+        // Update visualizations
+        const status = document.getElementById('scan-status');
+        if (status) {
+            const movingCount = scanData.bluetooth_devices.filter(d => d.is_moving).length;
+            const wsIndicator = wsConnected ? '[WS]' : '';
+            status.textContent = `Live${wsIndicator}: ${scanData.bluetooth_devices.length} BT (${movingCount} moving) @ ${new Date().toLocaleTimeString()}`;
+        }
+
+        // Update BT count
+        document.getElementById('bt-count').textContent = scanData.bluetooth_devices.length;
+        document.getElementById('bt-list-count').textContent = scanData.bluetooth_devices.length;
+
+        // Refresh views
+        drawRadar();
+        update3DMarkers();
+        updateMapMarkers();
+    }
+}
+
 // Toggle filter
 function toggleFilter(type) {
     filters[type] = !filters[type];
@@ -1925,17 +2078,23 @@ function toggleLiveTracking() {
 function startLiveTracking() {
     if (liveTrackingInterval) {
         clearInterval(liveTrackingInterval);
+        liveTrackingInterval = null;
     }
 
     liveTrackingEnabled = true;
     updateLiveTrackingUI();
-    console.log('Live BT tracking started');
 
-    // Do initial scan
-    performLiveBTScan();
-
-    // Set up interval
-    liveTrackingInterval = setInterval(performLiveBTScan, LIVE_TRACKING_INTERVAL_MS);
+    if (wsConnected) {
+        // WebSocket mode - updates come automatically via 'scanUpdate' events
+        // Still need to trigger initial scan
+        performLiveBTScan();
+        console.log('[Live] Started (WebSocket mode)');
+    } else {
+        // HTTP polling fallback
+        liveTrackingInterval = setInterval(performLiveBTScan, LIVE_TRACKING_INTERVAL_MS);
+        performLiveBTScan();
+        console.log('[Live] Started (HTTP polling mode)');
+    }
 }
 
 // Stop live BT tracking

src/rf_mapper/web/templates/index.html

@@ -166,5 +166,10 @@
 {% endblock %}
 
 {% block extra_js %}
+    <!-- Socket.IO client -->
+    <script src="{{ url_for('static', filename='js/vendor/socket.io.min.js') }}"></script>
+    <!-- WebSocket client module -->
+    <script src="{{ url_for('static', filename='js/websocket.js') }}"></script>
+    <!-- Main application -->
     <script src="{{ url_for('static', filename='js/app.js') }}"></script>
 {% endblock %}