bdk_demo: add receive address screen

bdk_demo/lib/core/router/app_router.dart

@@ -1,6 +1,7 @@
 import 'package:flutter_riverpod/misc.dart';
 import 'package:go_router/go_router.dart';
 import 'package:bdk_demo/features/home/home_page.dart';
+import 'package:bdk_demo/features/receive/receive_page.dart';
 import 'package:bdk_demo/features/transactions/transaction_detail_page.dart';
 import 'package:bdk_demo/features/transactions/transactions_list_page.dart';
 import 'package:bdk_demo/features/shared/widgets/placeholder_page.dart';
@@ -71,7 +72,7 @@ GoRouter createRouter(RouterRead read) => GoRouter(
     GoRoute(
       path: AppRoutes.receive,
       name: 'receive',
-      builder: (context, state) => const PlaceholderPage(title: 'Receive'),
+      builder: (context, state) => const ReceivePage(),
     ),
     GoRoute(
       path: AppRoutes.send,

bdk_demo/lib/features/receive/receive_address_card.dart

@@ -0,0 +1,70 @@
+import 'package:bdk_demo/core/theme/app_theme.dart';
+import 'package:bdk_demo/core/utils/clipboard_util.dart';
+import 'package:flutter/material.dart';
+import 'package:pretty_qr_code/pretty_qr_code.dart';
+
+class ReceiveAddressCard extends StatelessWidget {
+  const ReceiveAddressCard({
+    super.key,
+    required this.address,
+    required this.index,
+  });
+
+  final String address;
+  final int? index;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Card(
+      child: Padding(
+        padding: const EdgeInsets.all(24),
+        child: Column(
+          children: [
+            Container(
+              width: 240,
+              height: 240,
+              padding: const EdgeInsets.all(16),
+              decoration: BoxDecoration(
+                color: Colors.white,
+                borderRadius: BorderRadius.circular(16),
+              ),
+              child: PrettyQrView.data(
+                key: const Key('receive-address-qr'),
+                data: address,
+              ),
+            ),
+            const SizedBox(height: 20),
+            SelectableText(
+              address,
+              textAlign: TextAlign.center,
+              style: AppTheme.monoStyle.copyWith(
+                color: theme.colorScheme.onSurface,
+              ),
+            ),
+            if (index case final addressIndex?) ...[
+              const SizedBox(height: 10),
+              Text(
+                'External index $addressIndex',
+                style: theme.textTheme.labelLarge?.copyWith(
+                  color: theme.colorScheme.onSurface.withAlpha(170),
+                ),
+              ),
+            ],
+            const SizedBox(height: 16),
+            OutlinedButton.icon(
+              onPressed: () => ClipboardUtil.copyAndNotify(
+                context,
+                address,
+                message: 'Address copied',
+              ),
+              icon: const Icon(Icons.copy_outlined),
+              label: const Text('Copy address'),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

bdk_demo/lib/features/receive/receive_error_panel.dart

@@ -0,0 +1,36 @@
+import 'package:flutter/material.dart';
+
+class ReceiveErrorPanel extends StatelessWidget {
+  const ReceiveErrorPanel({super.key, required this.message});
+
+  final String message;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Container(
+      key: const Key('receive-error'),
+      padding: const EdgeInsets.all(16),
+      decoration: BoxDecoration(
+        color: theme.colorScheme.errorContainer,
+        borderRadius: BorderRadius.circular(12),
+      ),
+      child: Row(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Icon(Icons.error_outline, color: theme.colorScheme.error),
+          const SizedBox(width: 12),
+          Expanded(
+            child: Text(
+              message,
+              style: theme.textTheme.bodyMedium?.copyWith(
+                color: theme.colorScheme.onErrorContainer,
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}

bdk_demo/lib/features/receive/receive_page.dart

@@ -0,0 +1,88 @@
+import 'package:bdk_demo/features/receive/receive_address_card.dart';
+import 'package:bdk_demo/features/receive/receive_error_panel.dart';
+import 'package:bdk_demo/features/shared/widgets/secondary_app_bar.dart';
+import 'package:bdk_demo/features/shared/widgets/wallet_ui_helpers.dart';
+import 'package:bdk_demo/models/wallet_record.dart';
+import 'package:bdk_demo/providers/address_providers.dart';
+import 'package:bdk_demo/providers/wallet_providers.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+class ReceivePage extends ConsumerWidget {
+  const ReceivePage({super.key});
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final record = ref.watch(activeWalletRecordProvider);
+    final receiveState = ref.watch(currentReceiveAddressProvider);
+
+    return Scaffold(
+      appBar: const SecondaryAppBar(title: 'Receive'),
+      body: SafeArea(
+        child: record == null
+            ? const WalletStateCard(
+                icon: Icons.account_balance_wallet_outlined,
+                title: 'No active wallet',
+                message: 'Load a wallet before generating a receive address.',
+                centered: true,
+              )
+            : _buildWalletContent(context, ref, record, receiveState),
+      ),
+    );
+  }
+
+  Widget _buildWalletContent(
+    BuildContext context,
+    WidgetRef ref,
+    WalletRecord record,
+    ReceiveAddressState receiveState,
+  ) {
+    return ListView(
+      padding: const EdgeInsets.all(24),
+      children: [
+        Text(
+          'Receive on ${record.network.displayName}',
+          style: Theme.of(
+            context,
+          ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.w700),
+        ),
+        const SizedBox(height: 6),
+        Text(record.name, style: Theme.of(context).textTheme.bodyMedium),
+        const SizedBox(height: 20),
+        if (receiveState.address case final address?)
+          ReceiveAddressCard(address: address, index: receiveState.index)
+        else
+          WalletStateCard(
+            icon: Icons.qr_code_2,
+            title: receiveState.isGenerating
+                ? 'Generating address'
+                : 'Ready to receive',
+            message: receiveState.isGenerating
+                ? 'Revealing and saving the next external address.'
+                : 'Generate a fresh external address for this wallet.',
+            showSpinner: receiveState.isGenerating,
+          ),
+        if (receiveState.errorMessage case final error?) ...[
+          const SizedBox(height: 12),
+          ReceiveErrorPanel(message: error),
+        ],
+        const SizedBox(height: 20),
+        FilledButton.icon(
+          onPressed: receiveState.isGenerating
+              ? null
+              : () => ref
+                    .read(currentReceiveAddressProvider.notifier)
+                    .generateForActiveWallet(),
+          icon: const Icon(Icons.add_location_alt_outlined),
+          label: Text(
+            receiveState.address != null
+                ? 'Generate new address'
+                : receiveState.errorMessage != null
+                ? 'Try again'
+                : 'Generate address',
+          ),
+        ),
+      ],
+    );
+  }
+}

bdk_demo/test/presentation/receive_page_test.dart

@@ -0,0 +1,181 @@
+import 'package:bdk_demo/features/receive/receive_page.dart';
+import 'package:bdk_demo/models/wallet_record.dart';
+import 'package:bdk_demo/providers/address_providers.dart';
+import 'package:bdk_demo/providers/wallet_providers.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+const _testAddress = 'tb1qfm5n6w9u7r8ct3q3c2eqcdshw8f8hy5sjzlx6t';
+
+const _testRecord = WalletRecord(
+  id: 'wallet-1',
+  name: 'Receive Wallet',
+  network: WalletNetwork.testnet,
+  scriptType: ScriptType.p2wpkh,
+);
+
+class _FakeReceiveAddressNotifier extends CurrentReceiveAddressNotifier {
+  _FakeReceiveAddressNotifier(this.initialState);
+
+  final ReceiveAddressState initialState;
+  var generationCalls = 0;
+
+  @override
+  ReceiveAddressState build() => initialState;
+
+  @override
+  Future<void> generateForActiveWallet() async {
+    generationCalls += 1;
+  }
+}
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  Future<ProviderContainer> pumpReceivePage(
+    WidgetTester tester, {
+    required _FakeReceiveAddressNotifier notifier,
+    WalletRecord? activeWallet,
+  }) async {
+    final container = ProviderContainer(
+      overrides: [currentReceiveAddressProvider.overrideWith(() => notifier)],
+    );
+    addTearDown(container.dispose);
+
+    if (activeWallet != null) {
+      container.read(activeWalletRecordProvider.notifier).set(activeWallet);
+    }
+
+    await tester.pumpWidget(
+      UncontrolledProviderScope(
+        container: container,
+        child: const MaterialApp(home: ReceivePage()),
+      ),
+    );
+    await tester.pump();
+    return container;
+  }
+
+  testWidgets('shows generate action for an active wallet', (tester) async {
+    final notifier = _FakeReceiveAddressNotifier(ReceiveAddressState.empty);
+    await pumpReceivePage(
+      tester,
+      notifier: notifier,
+      activeWallet: _testRecord,
+    );
+
+    expect(find.text('Generate address'), findsOneWidget);
+
+    await tester.tap(find.text('Generate address'));
+    await tester.pump();
+
+    expect(notifier.generationCalls, 1);
+  });
+
+  testWidgets('shows QR, address, index, and new-address action', (
+    tester,
+  ) async {
+    final notifier = _FakeReceiveAddressNotifier(
+      const ReceiveAddressState(
+        walletId: 'wallet-1',
+        address: _testAddress,
+        index: 7,
+      ),
+    );
+    await pumpReceivePage(
+      tester,
+      notifier: notifier,
+      activeWallet: _testRecord,
+    );
+
+    expect(find.byKey(const Key('receive-address-qr')), findsOneWidget);
+    expect(find.text(_testAddress), findsOneWidget);
+    expect(find.text('External index 7'), findsOneWidget);
+
+    await tester.drag(find.byType(ListView), const Offset(0, -320));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Generate new address'), findsOneWidget);
+  });
+
+  testWidgets('shows loading and disables generation', (tester) async {
+    final notifier = _FakeReceiveAddressNotifier(
+      const ReceiveAddressState(walletId: 'wallet-1', isGenerating: true),
+    );
+    await pumpReceivePage(
+      tester,
+      notifier: notifier,
+      activeWallet: _testRecord,
+    );
+
+    expect(find.byType(CircularProgressIndicator), findsOneWidget);
+    expect(
+      tester.widget<FilledButton>(find.byType(FilledButton)).onPressed,
+      isNull,
+    );
+  });
+
+  testWidgets('shows provider error and retry action', (tester) async {
+    final notifier = _FakeReceiveAddressNotifier(
+      const ReceiveAddressState(
+        walletId: 'wallet-1',
+        errorMessage: 'StateError: generation failed',
+      ),
+    );
+    await pumpReceivePage(
+      tester,
+      notifier: notifier,
+      activeWallet: _testRecord,
+    );
+
+    expect(find.textContaining('generation failed'), findsOneWidget);
+    expect(find.text('Try again'), findsOneWidget);
+  });
+
+  testWidgets('copies the address and confirms the action', (tester) async {
+    final clipboardCalls = <MethodCall>[];
+    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+      SystemChannels.platform,
+      (call) async {
+        if (call.method == 'Clipboard.setData') clipboardCalls.add(call);
+        return null;
+      },
+    );
+    addTearDown(
+      () => tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(
+        SystemChannels.platform,
+        null,
+      ),
+    );
+
+    final notifier = _FakeReceiveAddressNotifier(
+      const ReceiveAddressState(
+        walletId: 'wallet-1',
+        address: _testAddress,
+        index: 0,
+      ),
+    );
+    await pumpReceivePage(
+      tester,
+      notifier: notifier,
+      activeWallet: _testRecord,
+    );
+
+    await tester.tap(find.text('Copy address'));
+    await tester.pump();
+
+    expect(clipboardCalls, hasLength(1));
+    expect(clipboardCalls.single.arguments, {'text': _testAddress});
+    expect(find.text('Address copied'), findsOneWidget);
+  });
+
+  testWidgets('shows safe state without an active wallet', (tester) async {
+    final notifier = _FakeReceiveAddressNotifier(ReceiveAddressState.empty);
+    await pumpReceivePage(tester, notifier: notifier);
+
+    expect(find.text('No active wallet'), findsOneWidget);
+    expect(find.text('Generate address'), findsNothing);
+  });
+}