new python build-deploy chain

pi/ui/lib/main.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+import 'dart:math';
 import 'package:flutter/material.dart';
 
 void main() {
@@ -19,13 +21,64 @@ class SmartSerowApp extends StatelessWidget {
         ),
         useMaterial3: true,
       ),
-      home: const HomePage(),
+      home: const AppRoot(),
     );
   }
 }
 
-class HomePage extends StatelessWidget {
-  const HomePage({super.key});
+/// Root widget that manages app state transitions
+class AppRoot extends StatefulWidget {
+  const AppRoot({super.key});
+
+  @override
+  State<AppRoot> createState() => _AppRootState();
+}
+
+class _AppRootState extends State<AppRoot> {
+  bool _initialized = false;
+  String _initStatus = 'Starting...';
+
+  @override
+  void initState() {
+    super.initState();
+    _runInitSequence();
+  }
+
+  Future<void> _runInitSequence() async {
+    // Simulate init checks - replace with real checks later
+    // (UART, GPS, sensors, etc.)
+
+    setState(() => _initStatus = 'Checking systems...');
+    await Future.delayed(const Duration(milliseconds: 800));
+
+    setState(() => _initStatus = 'UART: standby');
+    await Future.delayed(const Duration(milliseconds: 400));
+
+    setState(() => _initStatus = 'GPS: standby');
+    await Future.delayed(const Duration(milliseconds: 400));
+
+    setState(() => _initStatus = 'Ready');
+    await Future.delayed(const Duration(milliseconds: 300));
+
+    setState(() => _initialized = true);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return AnimatedSwitcher(
+      duration: const Duration(milliseconds: 500),
+      child: _initialized
+          ? const DashboardScreen(key: ValueKey('dashboard'))
+          : SplashScreen(key: const ValueKey('splash'), status: _initStatus),
+    );
+  }
+}
+
+/// Splash screen - shown during initialization
+class SplashScreen extends StatelessWidget {
+  final String status;
+
+  const SplashScreen({super.key, required this.status});
 
   @override
   Widget build(BuildContext context) {
@@ -48,9 +101,9 @@ class HomePage extends StatelessWidget {
                 fontWeight: FontWeight.bold,
               ),
             ),
-            const SizedBox(height: 8),
+            const SizedBox(height: 16),
             Text(
-              'System Ready',
+              status,
               style: Theme.of(context).textTheme.bodyLarge?.copyWith(
                 color: Colors.grey,
               ),
@@ -61,3 +114,141 @@ class HomePage extends StatelessWidget {
     );
   }
 }
+
+/// Main dashboard - placeholder with random updating values
+class DashboardScreen extends StatefulWidget {
+  const DashboardScreen({super.key});
+
+  @override
+  State<DashboardScreen> createState() => _DashboardScreenState();
+}
+
+class _DashboardScreenState extends State<DashboardScreen> {
+  final _random = Random();
+  Timer? _timer;
+
+  int _speed = 0;
+  int _rpm = 0;
+  double _voltage = 12.6;
+  int _temp = 25;
+
+  @override
+  void initState() {
+    super.initState();
+    // Update random values every 500ms - simulates live data
+    _timer = Timer.periodic(const Duration(milliseconds: 500), (_) {
+      setState(() {
+        _speed = _random.nextInt(120);
+        _rpm = 1000 + _random.nextInt(8000);
+        _voltage = 11.5 + _random.nextDouble() * 2;
+        _temp = 20 + _random.nextInt(60);
+      });
+    });
+  }
+
+  @override
+  void dispose() {
+    _timer?.cancel();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      backgroundColor: Colors.black,
+      body: Padding(
+        padding: const EdgeInsets.all(32),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.stretch,
+          children: [
+            // Header
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceBetween,
+              children: [
+                Text(
+                  'SMART SEROW',
+                  style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                    color: Colors.teal,
+                    letterSpacing: 2,
+                  ),
+                ),
+                Text(
+                  '${_voltage.toStringAsFixed(1)}V',
+                  style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                    color: _voltage < 12.0 ? Colors.red : Colors.green,
+                  ),
+                ),
+              ],
+            ),
+
+            const SizedBox(height: 48),
+
+            // Main speed display
+            Expanded(
+              child: Center(
+                child: Column(
+                  mainAxisAlignment: MainAxisAlignment.center,
+                  children: [
+                    Text(
+                      '$_speed',
+                      style: const TextStyle(
+                        fontSize: 180,
+                        fontWeight: FontWeight.w200,
+                        color: Colors.white,
+                        height: 1,
+                      ),
+                    ),
+                    Text(
+                      'km/h',
+                      style: Theme.of(context).textTheme.headlineSmall?.copyWith(
+                        color: Colors.grey,
+                      ),
+                    ),
+                  ],
+                ),
+              ),
+            ),
+
+            // Bottom stats row
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceAround,
+              children: [
+                _StatBox(label: 'RPM', value: _rpm.toString()),
+                _StatBox(label: 'TEMP', value: '$_temp°C'),
+                _StatBox(label: 'GEAR', value: '—'),
+              ],
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class _StatBox extends StatelessWidget {
+  final String label;
+  final String value;
+
+  const _StatBox({required this.label, required this.value});
+
+  @override
+  Widget build(BuildContext context) {
+    return Column(
+      children: [
+        Text(
+          value,
+          style: Theme.of(context).textTheme.headlineMedium?.copyWith(
+            color: Colors.white,
+          ),
+        ),
+        Text(
+          label,
+          style: Theme.of(context).textTheme.bodySmall?.copyWith(
+            color: Colors.grey,
+            letterSpacing: 1,
+          ),
+        ),
+      ],
+    );
+  }
+}