feat: fullscreen OTA with back-block and warning

lib/pages/device_details_page.dart

@@ -735,7 +735,7 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
       ScaffoldMessenger.of(context).showSnackBar(
         const SnackBar(
           content: Text(
-              'Firmware update is running. Keep this screen open until it completes.'),
+              'Firmware update is running. Do not close this screen or the app until it completes.'),
         ),
       );
       return;
@@ -748,6 +748,21 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
     context.go('/devices');
   }
 
+  void _dismissFirmwareFullscreen() {
+    setState(() {
+      _dfuProgress = const DfuUpdateProgress(
+        state: DfuUpdateState.idle,
+        totalBytes: 0,
+        sentBytes: 0,
+        expectedOffset: 0,
+        sessionId: 0,
+        flags: DfuUpdateFlags(),
+      );
+      _firmwareUserMessage = null;
+      _selectedFirmware = null;
+    });
+  }
+
   void _showStatusHistory() {
     showModalBottomSheet<void>(
       context: context,
@@ -874,6 +889,23 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
         !_isSelectingFirmware &&
         !_isFirmwareUpdateBusy &&
         _selectedFirmware != null;
+    if (_isFirmwareUpdateBusy ||
+        (_dfuProgress.state != DfuUpdateState.idle &&
+            _dfuProgress.state != DfuUpdateState.completed &&
+            _dfuProgress.state != DfuUpdateState.failed)) {
+      return _FirmwareUpdateFullscreen(
+        progress: _dfuProgress,
+        selectedFirmware: _selectedFirmware,
+        phaseText: _dfuPhaseText(_dfuProgress.state),
+        statusText: _firmwareUserMessage,
+        formattedProgressBytes:
+            '${_formatBytes(_dfuProgress.sentBytes)} / ${_formatBytes(_dfuProgress.totalBytes)}',
+        expectedOffsetHex:
+            '0x${_dfuProgress.expectedOffset.toRadixString(16).padLeft(8, '0').toUpperCase()}',
+        onDismiss: _dismissFirmwareFullscreen,
+      );
+    }
+
     return PopScope(
       canPop: false,
       onPopInvokedWithResult: (bool didPop, bool? result) {
@@ -938,22 +970,16 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
                     const SizedBox(height: 16),
                     _TrainerConnectionCard(
                       status: _latestStatus,
-                      onAssign:
+                      onAssign: _connectButtonToBike,
-                          _isFirmwareUpdateBusy ? null : _connectButtonToBike,
                       onShowStatusConsole: _showStatusHistory,
                     ),
                     const SizedBox(height: 16),
-                    Opacity(
+                    GearRatioEditorCard(
-                      opacity: _isFirmwareUpdateBusy ? 0.6 : 1,
-                      child: AbsorbPointer(
-                        absorbing: _isFirmwareUpdateBusy,
-                        child: GearRatioEditorCard(
                       ratios: _gearRatios,
                       defaultGearIndex: _defaultGearIndex,
                       isLoading: _isGearRatiosLoading,
                       errorText: _gearRatiosError,
-                          onRetry:
+                      onRetry: _loadGearRatios,
-                              _isFirmwareUpdateBusy ? null : _loadGearRatios,
                       onSave: _saveGearRatios,
                       presets: const [
                         GearRatioPreset(
@@ -1021,13 +1047,11 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
                         ),
                       ],
                     ),
-                      ),
-                    ),
                   ] else if (isCurrentConnected) ...[
                     _PairingRequiredCard(
                       isChecking: _isPairingCheckRunning,
                       errorText: _pairingError,
-                      onRetry: _isFirmwareUpdateBusy ? null : _retryPairing,
+                      onRetry: _retryPairing,
                       onOpenBluetoothSettings: _openPairingSettings,
                     ),
                   ] else ...[
@@ -1921,3 +1945,244 @@ class _OverviewMetricTile extends StatelessWidget {
     );
   }
 }
+
+class _FirmwareUpdateFullscreen extends StatelessWidget {
+  const _FirmwareUpdateFullscreen({
+    required this.progress,
+    required this.selectedFirmware,
+    required this.phaseText,
+    required this.statusText,
+    required this.formattedProgressBytes,
+    required this.expectedOffsetHex,
+    required this.onDismiss,
+  });
+
+  final DfuUpdateProgress progress;
+  final BootloaderDfuPreparedFirmware? selectedFirmware;
+  final String phaseText;
+  final String? statusText;
+  final String formattedProgressBytes;
+  final String expectedOffsetHex;
+  final VoidCallback onDismiss;
+
+  bool get _isTerminal =>
+      progress.state == DfuUpdateState.completed ||
+      progress.state == DfuUpdateState.failed;
+
+  bool get _isRunning => !_isTerminal && progress.state != DfuUpdateState.idle;
+
+  String? get _bootloaderStatusText {
+    final status = progress.bootloaderStatus;
+    if (status == null) {
+      return null;
+    }
+    final codeLabel = switch (status.code) {
+      DfuBootloaderStatusCode.ok => 'OK',
+      DfuBootloaderStatusCode.parseError => 'parse error',
+      DfuBootloaderStatusCode.stateError => 'state error',
+      DfuBootloaderStatusCode.boundsError => 'bounds error',
+      DfuBootloaderStatusCode.crcError => 'CRC error',
+      DfuBootloaderStatusCode.flashError => 'flash error',
+      DfuBootloaderStatusCode.unsupportedError => 'unsupported flags',
+      DfuBootloaderStatusCode.vectorError => 'vector table error',
+      DfuBootloaderStatusCode.queueFull => 'queue full',
+      DfuBootloaderStatusCode.bootMetadataError => 'boot metadata error',
+      DfuBootloaderStatusCode.unknown =>
+        'unknown 0x${status.rawCode.toRadixString(16).padLeft(2, '0').toUpperCase()}',
+    };
+    return '$codeLabel  •  session ${status.sessionId}  •  offset 0x${status.expectedOffset.toRadixString(16).padLeft(8, '0').toUpperCase()}';
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final colorScheme = theme.colorScheme;
+    final isFailed = progress.state == DfuUpdateState.failed;
+
+    return PopScope(
+      canPop: false,
+      child: Scaffold(
+        backgroundColor: colorScheme.surface,
+        body: SafeArea(
+          child: Column(
+            children: [
+              if (_isRunning)
+                Container(
+                  width: double.infinity,
+                  padding:
+                      const EdgeInsets.symmetric(horizontal: 20, vertical: 12),
+                  color: colorScheme.errorContainer,
+                  child: Row(
+                    children: [
+                      Icon(Icons.warning_amber_rounded,
+                          color: colorScheme.onErrorContainer, size: 20),
+                      const SizedBox(width: 10),
+                      Expanded(
+                        child: Text(
+                          'Do not close the app, lock the phone, or move away from the button.',
+                          style: theme.textTheme.bodySmall?.copyWith(
+                            color: colorScheme.onErrorContainer,
+                            fontWeight: FontWeight.w600,
+                          ),
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+              Expanded(
+                child: SingleChildScrollView(
+                  padding: const EdgeInsets.fromLTRB(24, 32, 24, 24),
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.center,
+                    children: [
+                      Icon(
+                        _isTerminal
+                            ? (isFailed
+                                ? Icons.error_outline_rounded
+                                : Icons.check_circle_outline_rounded)
+                            : Icons.system_update_alt_rounded,
+                        size: 56,
+                        color: _isTerminal
+                            ? (isFailed
+                                ? colorScheme.error
+                                : colorScheme.primary)
+                            : colorScheme.primary,
+                      ),
+                      const SizedBox(height: 16),
+                      Text(
+                        _isTerminal
+                            ? (isFailed ? 'Update failed' : 'Update completed')
+                            : 'Updating firmware',
+                        style: theme.textTheme.headlineSmall?.copyWith(
+                          fontWeight: FontWeight.w700,
+                        ),
+                      ),
+                      const SizedBox(height: 8),
+                      Text(
+                        phaseText,
+                        style: theme.textTheme.bodyLarge?.copyWith(
+                          color: colorScheme.onSurface.withValues(alpha: 0.72),
+                        ),
+                      ),
+                      if (selectedFirmware != null) ...[
+                        const SizedBox(height: 12),
+                        Text(
+                          '${selectedFirmware!.fileName}  •  ${_formatBytes(selectedFirmware!.fileBytes.length)}',
+                          style: theme.textTheme.bodySmall,
+                        ),
+                      ],
+                      const SizedBox(height: 24),
+                      if (_isRunning) ...[
+                        LinearProgressIndicator(
+                          value: progress.totalBytes > 0
+                              ? progress.fractionComplete
+                              : null,
+                          minHeight: 12,
+                          borderRadius: BorderRadius.circular(999),
+                        ),
+                        const SizedBox(height: 12),
+                        Text(
+                          '${progress.percentComplete}%  •  $formattedProgressBytes',
+                          style: theme.textTheme.bodyMedium?.copyWith(
+                            fontWeight: FontWeight.w600,
+                          ),
+                        ),
+                      ],
+                      if (progress.state == DfuUpdateState.finishing ||
+                          progress.state == DfuUpdateState.rebooting ||
+                          progress.state == DfuUpdateState.verifying) ...[
+                        const SizedBox(height: 20),
+                        Container(
+                          width: double.infinity,
+                          padding: const EdgeInsets.all(14),
+                          decoration: BoxDecoration(
+                            color: colorScheme.primaryContainer
+                                .withValues(alpha: 0.36),
+                            borderRadius: BorderRadius.circular(14),
+                          ),
+                          child: Row(
+                            children: [
+                              SizedBox(
+                                width: 18,
+                                height: 18,
+                                child: CircularProgressIndicator(
+                                    strokeWidth: 2, color: colorScheme.primary),
+                              ),
+                              const SizedBox(width: 10),
+                              Expanded(
+                                child: Text(
+                                  'Bootloader is verifying, resetting, and booting the new app. Keep the screen open.',
+                                  style: theme.textTheme.bodySmall?.copyWith(
+                                    color: colorScheme.primary,
+                                    fontWeight: FontWeight.w600,
+                                  ),
+                                ),
+                              ),
+                            ],
+                          ),
+                        ),
+                      ],
+                      if (_bootloaderStatusText != null) ...[
+                        const SizedBox(height: 12),
+                        Text(
+                          _bootloaderStatusText!,
+                          style: theme.textTheme.bodySmall?.copyWith(
+                            color:
+                                colorScheme.onSurface.withValues(alpha: 0.56),
+                          ),
+                        ),
+                      ],
+                      if (statusText != null &&
+                          statusText!.trim().isNotEmpty) ...[
+                        const SizedBox(height: 20),
+                        Container(
+                          width: double.infinity,
+                          padding: const EdgeInsets.all(14),
+                          decoration: BoxDecoration(
+                            color: isFailed
+                                ? colorScheme.errorContainer
+                                : colorScheme.surfaceContainerHighest,
+                            borderRadius: BorderRadius.circular(14),
+                          ),
+                          child: Text(
+                            statusText!,
+                            style: theme.textTheme.bodyMedium?.copyWith(
+                              color: isFailed
+                                  ? colorScheme.onErrorContainer
+                                  : null,
+                            ),
+                          ),
+                        ),
+                      ],
+                      if (_isTerminal) ...[
+                        const SizedBox(height: 32),
+                        SizedBox(
+                          width: double.infinity,
+                          child: FilledButton.icon(
+                            onPressed: onDismiss,
+                            icon: Icon(isFailed
+                                ? Icons.arrow_back_rounded
+                                : Icons.check_rounded),
+                            label: Text(
+                              isFailed ? 'Back to device' : 'Done',
+                            ),
+                          ),
+                        ),
+                      ],
+                    ],
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  String _formatBytes(int bytes) {
+    if (bytes < 1024) return '$bytes B';
+    if (bytes < 1024 * 1024) return '${(bytes / 1024).toStringAsFixed(1)} KB';
+    return '${(bytes / (1024 * 1024)).toStringAsFixed(2)} MB';
+  }
+}