scan deep link QR from send page

mobile-app/lib/providers/route_intent_providers.dart

@@ -10,6 +10,15 @@ class PaymentIntent {
   final String? ref;
 
   const PaymentIntent({required this.to, required this.amount, this.ref});
+
+  static PaymentIntent? tryParseUrl(String input) {
+    final uri = Uri.tryParse(input);
+    if (uri == null || uri.pathSegments.isEmpty || uri.pathSegments.first != 'pay') return null;
+    final to = uri.queryParameters['to'];
+    final amount = uri.queryParameters['amount'];
+    if (to == null || to.isEmpty || amount == null || amount.isEmpty) return null;
+    return PaymentIntent(to: to, amount: amount, ref: uri.queryParameters['ref']);
+  }
 }
 
 final paymentIntentProvider = StateProvider<PaymentIntent?>((_) => null);

mobile-app/lib/services/deep_link_service.dart

@@ -54,12 +54,9 @@ class DeepLinkService {
     }
 
     if (uri.pathSegments.isNotEmpty && uri.pathSegments.first == 'pay') {
-      final to = uri.queryParameters['to'];
-      final amount = uri.queryParameters['amount'];
-      final ref = uri.queryParameters['ref'];
-
-      if (to != null && to.isNotEmpty && amount != null && amount.isNotEmpty) {
-        _ref.read(paymentIntentProvider.notifier).state = PaymentIntent(to: to, amount: amount, ref: ref);
+      final payment = PaymentIntent.tryParseUrl(uri.toString());
+      if (payment != null) {
+        _ref.read(paymentIntentProvider.notifier).state = payment;
         navigatorKey.currentState?.pushNamed('/account');
       } else {
         print('Missing payment parameters');

mobile-app/lib/v2/components/qr_scanner_page.dart

@@ -6,7 +6,8 @@ import 'package:resonance_network_wallet/v2/components/glass_icon_button.dart';
 import 'package:resonance_network_wallet/v2/theme/app_colors.dart';
 
 class QrScannerPage extends StatefulWidget {
-  const QrScannerPage({super.key});
+  final bool Function(String)? validator;
+  const QrScannerPage({super.key, this.validator});
 
   @override
   State<QrScannerPage> createState() => _QrScannerPageState();
@@ -25,10 +26,10 @@ class _QrScannerPageState extends State<QrScannerPage> {
   void _onDetect(BarcodeCapture capture) {
     if (_scanned) return;
     final code = capture.barcodes.firstOrNull?.rawValue;
-    if (code != null && code.isNotEmpty) {
-      _scanned = true;
-      Navigator.pop(context, code);
-    }
+    if (code == null || code.isEmpty) return;
+    if (widget.validator != null && !widget.validator!(code)) return;
+    _scanned = true;
+    Navigator.pop(context, code);
   }
 
   Future<void> _pickImage() async {

mobile-app/lib/v2/screens/send/send_sheet.dart

@@ -8,6 +8,7 @@ import 'package:quantus_sdk/quantus_sdk.dart';
 import 'package:resonance_network_wallet/v2/screens/send/send_providers.dart';
 import 'package:resonance_network_wallet/v2/screens/send/send_screen_logic.dart';
 import 'package:resonance_network_wallet/providers/account_providers.dart';
+import 'package:resonance_network_wallet/providers/route_intent_providers.dart';
 import 'package:resonance_network_wallet/providers/wallet_providers.dart';
 import 'package:resonance_network_wallet/services/transaction_submission_service.dart';
 import 'package:resonance_network_wallet/v2/components/success_check.dart';
@@ -120,12 +121,24 @@ class _SendSheetState extends ConsumerState<SendSheet> {
   }
 
   Future<void> _scanQr() async {
-    final address = await Navigator.push<String>(
+    final substrate = ref.read(substrateServiceProvider);
+    final scanResult = await Navigator.push<String>(
       context,
-      MaterialPageRoute(fullscreenDialog: true, builder: (_) => const QrScannerPage()),
+      MaterialPageRoute(
+        fullscreenDialog: true,
+        builder: (_) => QrScannerPage(
+          validator: (code) => substrate.isValidSS58Address(code) || PaymentIntent.tryParseUrl(code) != null,
+        ),
+      ),
     );
-    if (address != null && mounted) {
-      _recipientController.text = address;
+    // scanResult is either a valid address or a valid payment intent or null
+    if (scanResult == null || !mounted) return;
+    final payment = PaymentIntent.tryParseUrl(scanResult);
+    if (payment != null) {
+      _recipientController.text = payment.to;
+      _amountController.text = payment.amount;
+    } else {
+      _recipientController.text = scanResult;
     }
   }