[NWC] add hold invoice support

packages/ndk/android/app/src/main/java/io/flutter/plugins/GeneratedPluginRegistrant.java

@@ -0,0 +1,19 @@
+package io.flutter.plugins;
+
+import androidx.annotation.Keep;
+import androidx.annotation.NonNull;
+import io.flutter.Log;
+
+import io.flutter.embedding.engine.FlutterEngine;
+
+/**
+ * Generated file. Do not edit.
+ * This file is generated by the Flutter tool based on the
+ * plugins that support the Android platform.
+ */
+@Keep
+public final class GeneratedPluginRegistrant {
+  private static final String TAG = "GeneratedPluginRegistrant";
+  public static void registerWith(@NonNull FlutterEngine flutterEngine) {
+  }
+}

packages/ndk/example/nwc/list_transactions.dart

@@ -14,11 +14,11 @@ void main() async {
   final connection = await ndk.nwc.connect(nwcUri);
 
   ListTransactionsResponse response =
-      await ndk.nwc.listTransactions(connection, unpaid: false);
+      await ndk.nwc.listTransactions(connection, unpaid: true);
 
   for (final transaction in response.transactions) {
     print(
-        "Transaction ${transaction.type} ${transaction.amountSat} sats ${transaction.description!}");
+        "Transaction ${transaction.type} state ${transaction.state} ${transaction.amountSat} sats ${transaction.description!}");
   }
   await ndk.destroy();
 }

packages/ndk/example/nwc/make_hold_invoice.dart

@@ -0,0 +1,127 @@
+// ignore_for_file: avoid_print
+
+import 'dart:async';
+import 'dart:io';
+import 'dart:math';
+import 'dart:typed_data';
+import 'package:crypto/crypto.dart';
+import 'package:convert/convert.dart';
+import 'package:ascii_qr/ascii_qr.dart';
+import 'package:ndk/domain_layer/usecases/nwc/nwc_notification.dart';
+
+import 'package:ndk/ndk.dart';
+
+void main() async {
+  // We use an empty bootstrap relay list,
+  // since NWC will provide the relay we connect to so we don't need default relays
+  final ndk = Ndk.emptyBootstrapRelaysConfig();
+
+  // You need an NWC_URI env var or to replace with your NWC uri connection
+  final nwcUri = Platform.environment['NWC_URI']!;
+  final connection = await ndk.nwc.connect(nwcUri);
+
+  final amount = 29;
+  final description = "hello hold";
+
+  // Generate a random 32-byte preimage
+  final random = Random.secure();
+  final preimageBytes =
+      Uint8List.fromList(List<int>.generate(32, (_) => random.nextInt(256)));
+  final preimageHex =
+      hex.encode(preimageBytes); // Optional: hex encode for printing
+
+  // Calculate the payment hash (SHA256 of the preimage)
+  final paymentHashBytes = sha256.convert(preimageBytes).bytes;
+  final paymentHash = hex.encode(paymentHashBytes);
+
+  print("Generated Preimage: $preimageHex");
+  print("Generated Payment Hash: $paymentHash");
+
+  try {
+    // 1. Create the hold invoice
+    print("Creating hold invoice...");
+    final makeResponse = await ndk.nwc.makeHoldInvoice(connection,
+        amountSats: amount, description: description, paymentHash: paymentHash);
+
+    if (makeResponse.errorCode == null) {
+      // Check if errorCode is null for success
+      final invoice = makeResponse.invoice;
+      print(
+          "Hold invoice created successfully. Invoice: $invoice, Payment Hash: ${makeResponse.paymentHash}");
+
+      if (invoice.isNotEmpty) {
+        print("\nScan QR Code to pay/hold:");
+        try {
+          final asciiQr = AsciiQrGenerator.generate(
+            invoice.toUpperCase(),
+          );
+          print(asciiQr.toString());
+        } catch (e) {
+          print("Error generating ASCII QR code: $e");
+        }
+        print("\nOr copy Bolt11 invoice:\n$invoice\n");
+      }
+
+      final duration = makeResponse.expiresAt!-DateTime.now().millisecondsSinceEpoch ~/ 1000;
+      print(
+          "Waiting for hold invoice acceptance notification (max $duration seconds)...");
+      try {
+        final acceptedNotification = await connection.holdInvoiceStateStream
+            .firstWhere((notification) {
+          return notification.notificationType == NwcNotification.kHoldInvoiceAccepted;
+        }).timeout(Duration(seconds: duration.toInt()));
+
+        print(
+            "Hold invoice accepted by wallet! (Notification: ${acceptedNotification.notificationType})");
+
+        // 3. Ask user whether to settle or cancel
+        print("Settle this accepted invoice? (Y/N)");
+        String? input = stdin.readLineSync()?.trim().toLowerCase();
+
+        if (input == 'n') {
+          // 4a. Cancel the hold invoice
+          print("Canceling hold invoice with payment hash: $paymentHash...");
+          final cancelResponse = await ndk.nwc
+              .cancelHoldInvoice(connection, paymentHash: paymentHash);
+
+          if (cancelResponse.errorCode == null) {
+            // Check if errorCode is null for success
+            print("Hold invoice canceled successfully.");
+          } else {
+            print(
+                "Failed to cancel hold invoice. Error: ${cancelResponse.errorMessage} (Code: ${cancelResponse.errorCode})");
+          }
+        } else if (input == 'y') {
+          // 4b. Settle the hold invoice using the preimage
+          print("Settling hold invoice with preimage: $preimageHex...");
+          final settleResponse = await ndk.nwc
+              .settleHoldInvoice(connection, preimage: preimageHex);
+
+          if (settleResponse.errorCode == null) {
+            print(
+                "Hold invoice settled successfully. Preimage used: $preimageHex");
+          } else {
+            print(
+                "Failed to settle hold invoice. Error: ${settleResponse.errorMessage} (Code: ${settleResponse.errorCode})");
+          }
+        } else {
+          print("Invalid input. Not settling or canceling.");
+        }
+      } on TimeoutException {
+        print(
+            "Timed out waiting for hold invoice acceptance notification. The invoice might not be held by the wallet.");
+        // Optionally, try to cancel here as a fallback?
+      } catch (e) {
+        print("Error waiting for notification: $e");
+      }
+    } else {
+      print(
+          "Failed to create hold invoice. Error: ${makeResponse.errorMessage} (Code: ${makeResponse.errorCode})");
+    }
+  } catch (e) {
+    print("An error occurred: $e");
+  } finally {
+    // Ensure ndk.destroy() is called in the finally block
+    await ndk.destroy();
+  }
+}

packages/ndk/lib/domain_layer/usecases/nwc/consts/nwc_method.dart

@@ -15,6 +15,9 @@ class NwcMethod {
   static const NwcMethod PAY_KEYSEND = NwcMethod('pay_keysend');
   static const NwcMethod MULTI_PAY_KEYSEND = NwcMethod('multi_pay_keysend');
   static const NwcMethod MAKE_INVOICE = NwcMethod('make_invoice');
+  static const NwcMethod MAKE_HOLD_INVOICE = NwcMethod('make_hold_invoice');
+  static const NwcMethod CANCEL_HOLD_INVOICE = NwcMethod('cancel_hold_invoice');
+  static const NwcMethod SETTLE_HOLD_INVOICE = NwcMethod('settle_hold_invoice');
   static const NwcMethod LOOKUP_INVOICE = NwcMethod('lookup_invoice');
   static const NwcMethod LIST_TRANSACTIONS = NwcMethod('list_transactions');
   static const NwcMethod UNKNOWN = NwcMethod('unknown');
@@ -26,6 +29,9 @@ class NwcMethod {
     PAY_KEYSEND.name: PAY_KEYSEND,
     MULTI_PAY_KEYSEND.name: MULTI_PAY_KEYSEND,
     MAKE_INVOICE.name: MAKE_INVOICE,
+    MAKE_HOLD_INVOICE.name: MAKE_HOLD_INVOICE,
+    CANCEL_HOLD_INVOICE.name: CANCEL_HOLD_INVOICE,
+    SETTLE_HOLD_INVOICE.name: SETTLE_HOLD_INVOICE,
     LOOKUP_INVOICE.name: LOOKUP_INVOICE,
     LIST_TRANSACTIONS.name: LIST_TRANSACTIONS,
     GET_BALANCE.name: GET_BALANCE,

packages/ndk/lib/domain_layer/usecases/nwc/nwc.dart

@@ -17,6 +17,9 @@
 import 'requests/list_transactions.dart';
 import 'requests/lookup_invoice.dart';
 import 'requests/make_invoice.dart';
+import 'requests/make_hold_invoice.dart'; // Add import for MakeHoldInvoiceRequest
+import 'requests/cancel_hold_invoice.dart'; // Add import for CancelHoldInvoiceRequest
+import 'requests/settle_hold_invoice.dart'; // Add import for SettleHoldInvoiceRequest
 import 'requests/nwc_request.dart';
 import 'requests/pay_invoice.dart';
 import 'responses/nwc_response.dart';
@@ -150,14 +153,18 @@
           response = GetBalanceResponse.deserialize(data);
         } else if (data['result_type'] == NwcMethod.GET_BUDGET.name) {
           response = GetBudgetResponse.deserialize(data);
-        } else if (data['result_type'] == NwcMethod.MAKE_INVOICE.name) {
+        } else if (data['result_type'] == NwcMethod.MAKE_INVOICE.name ||
+            data['result_type'] == NwcMethod.MAKE_HOLD_INVOICE.name) {
           response = MakeInvoiceResponse.deserialize(data);
         } else if (data['result_type'] == NwcMethod.PAY_INVOICE.name) {
           response = PayInvoiceResponse.deserialize(data);
         } else if (data['result_type'] == NwcMethod.LIST_TRANSACTIONS.name) {
           response = ListTransactionsResponse.deserialize(data);
         } else if (data['result_type'] == NwcMethod.LOOKUP_INVOICE.name) {
           response = LookupInvoiceResponse.deserialize(data);
+        } else if (data['result_type'] == NwcMethod.CANCEL_HOLD_INVOICE.name || data['result_type'] == NwcMethod.SETTLE_HOLD_INVOICE.name) {
+          response =
+              NwcResponse(resultType: data['result_type']); // Generic response
         }
       } else {
         response = NwcResponse(resultType: data['result_type']);
@@ -192,7 +199,7 @@
       if (data.containsKey("notification_type") &&
           data['notification'] != null) {
         NwcNotification notification =
-            NwcNotification.fromMap(data['notification']);
+            NwcNotification.fromMap(data["notification_type"],data['notification']);
         connection.notificationStream.add(notification);
       } else if (data.containsKey("error")) {
         // TODO: Define what to do when data has an error
@@ -213,7 +220,7 @@
       if (data.containsKey("notification_type") &&
           data['notification'] != null) {
         NwcNotification notification =
-            NwcNotification.fromMap(data['notification']);
+            NwcNotification.fromMap(data["notification_type"],data['notification']);
         connection.notificationStream.add(notification);
       } else if (data.containsKey("error")) {
         // TODO: Define what to do when data has an error
@@ -282,7 +289,7 @@
     return _executeRequest<GetBudgetResponse>(connection, GetBudgetRequest());
   }
 
-  /// Does a `make_invoie` request
+  /// Does a `make_invoice` request
   Future<MakeInvoiceResponse> makeInvoice(NwcConnection connection,
       {required int amountSats,
       String? description,
@@ -297,6 +304,37 @@
             expiry: expiry));
   }
 
+  /// Does a `make_hold_invoice` request
+  Future<MakeInvoiceResponse> makeHoldInvoice(NwcConnection connection,
+      {required int amountSats,
+      String? description,
+      String? descriptionHash,
+      int? expiry,
+      required String paymentHash}) async {
+    return _executeRequest<MakeInvoiceResponse>(
+        connection,
+        MakeHoldInvoiceRequest(
+            amountMsat: amountSats * 1000,
+            description: description,
+            descriptionHash: descriptionHash,
+            expiry: expiry,
+            paymentHash: paymentHash));
+  }
+
+  /// Does a `cancel_hold_invoice` request
+  Future<NwcResponse> cancelHoldInvoice(NwcConnection connection,
+      {required String paymentHash}) async {
+    return _executeRequest<NwcResponse>(
+        connection, CancelHoldInvoiceRequest(paymentHash: paymentHash));
+  }
+
+  /// Does a `settle_hold_invoice` request
+  Future<NwcResponse> settleHoldInvoice(NwcConnection connection,
+      {required String preimage}) async {
+    return _executeRequest<NwcResponse>(
+        connection, SettleHoldInvoiceRequest(preimage: preimage));
+  }
+
   /// Does a `pay_invoice` request
   Future<PayInvoiceResponse> payInvoice(NwcConnection connection,
       {required String invoice, Duration? timeout}) async {

packages/ndk/lib/domain_layer/usecases/nwc/nwc_connection.dart

@@ -23,11 +23,16 @@
 
   Stream<NwcNotification> get paymentsReceivedStream =>
       notificationStream.stream
-          .where((notification) => notification.isIncoming)
+          .where((notification) => notification.isPaymentReceived)
           .asBroadcastStream();
 
+
   Stream<NwcNotification> get paymentsSentStream => notificationStream.stream
-      .where((notification) => !notification.isIncoming)
+      .where((notification) => notification.isPaymentSent)
+      .asBroadcastStream();
+
+  Stream<NwcNotification> get holdInvoiceStateStream => notificationStream.stream
+      .where((notification) => notification.isHoldInvoiceAccepted)
       .asBroadcastStream();
 
   /// listen

packages/ndk/lib/domain_layer/usecases/nwc/nwc_notification.dart

@@ -3,39 +3,46 @@
 class NwcNotification {
   static const kPaymentReceived = "payment_received";
   static const kPaymentSent = "payment_sent";
+  static const kHoldInvoiceAccepted = "hold_invoice_accepted";
 
+  String notificationType;
   String type;
   String invoice;
   String? description;
   String? descriptionHash;
-  String preimage;
+  String? preimage;
   String paymentHash;
   int amount;
-  int feesPaid;
+  int? feesPaid;
   int createdAt;
   int? expiresAt;
-  int settledAt;
+  int? settledAt;
   Map<String, dynamic>? metadata;
 
   get isIncoming => type == TransactionType.incoming.value;
+  get isPaymentReceived => notificationType == kPaymentReceived;
+  get isPaymentSent => notificationType == kPaymentSent;
+  get isHoldInvoiceAccepted => notificationType == kHoldInvoiceAccepted;
 
   NwcNotification({
+    required this.notificationType,
     required this.type,
     required this.invoice,
     this.description,
     this.descriptionHash,
-    required this.preimage,
+    this.preimage,
     required this.paymentHash,
     required this.amount,
-    required this.feesPaid,
+    this.feesPaid,
     required this.createdAt,
     this.expiresAt,
-    required this.settledAt,
-    required this.metadata,
+    this.settledAt,
+    this.metadata,
   });
 
-  factory NwcNotification.fromMap(Map<String, dynamic> map) {
+  factory NwcNotification.fromMap(String notificationType, Map<String, dynamic> map) {
     return NwcNotification(
+      notificationType: notificationType,
       type: map['type'] as String,
       invoice: map['invoice'] as String,
       description: map['description'] as String?,
@@ -46,10 +53,15 @@
       feesPaid: map['fees_paid'] as int,
       createdAt: map['created_at'] as int,
       expiresAt: map['expires_at'] as int?,
-      settledAt: map['settled_at'] as int,
+      settledAt: map['settled_at'] as int?,
       metadata: map.containsKey('metadata') && map['metadata'] != null
           ? Map<String, dynamic>.from(map['metadata'])
           : null,
     );
   }
+
+  @override
+  toString() {
+    return 'NwcNotification{type: $type, invoice: $invoice, description: $description, descriptionHash: $descriptionHash, preimage: $preimage, paymentHash: $paymentHash, amount: $amount, feesPaid: $feesPaid, createdAt: $createdAt, expiresAt: $expiresAt, settledAt: $settledAt, metadata: $metadata}';
+  }
 }

packages/ndk/lib/domain_layer/usecases/nwc/requests/cancel_hold_invoice.dart

@@ -0,0 +1,21 @@
+import 'package:ndk/domain_layer/usecases/nwc/consts/nwc_method.dart';
+
+import 'nwc_request.dart';
+
+class CancelHoldInvoiceRequest extends NwcRequest {
+  final String paymentHash;
+
+  const CancelHoldInvoiceRequest({
+    required this.paymentHash,
+  }) : super(method: NwcMethod.CANCEL_HOLD_INVOICE);
+
+  @override
+  Map<String, dynamic> toMap() {
+    return {
+      ...super.toMap(),
+      'params': {
+        'payment_hash': paymentHash,
+      }
+    };
+  }
+}