From 10499814bb9d1f58d78a80b971b5be0bbf299266 Mon Sep 17 00:00:00 2001
From: rafael_xmr <g.pi8ax@slmail.me>
Date: Tue, 29 Jul 2025 09:50:11 -0300
Subject: [PATCH] warn sp dust (#2402)

* feat: warn sp dust

* Update lib/view_model/send/send_view_model.dart

* fix condition

---------

Co-authored-by: Omar Hatem <omarh.ismail1@gmail.com>
---
 cw_bitcoin/lib/electrum_wallet.dart         | 26 +++++++++++++++++++--
 lib/src/screens/send/widgets/send_card.dart |  2 +-
 lib/view_model/send/send_view_model.dart    | 26 +++++++++++++++++----
 3 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/cw_bitcoin/lib/electrum_wallet.dart b/cw_bitcoin/lib/electrum_wallet.dart
index 28d0e323a..eb03514ae 100644
--- a/cw_bitcoin/lib/electrum_wallet.dart
+++ b/cw_bitcoin/lib/electrum_wallet.dart
@@ -780,7 +780,11 @@ abstract class ElectrumWalletBase
     }
 
     if (outputs.length == 1) {
-      outputs[0] = BitcoinOutput(address: outputs.last.address, value: BigInt.from(amount));
+      outputs[0] = BitcoinOutput(
+        address: outputs.last.address,
+        value: BigInt.from(amount),
+        isSilentPayment: hasSilentPayment,
+      );
     }
 
     return EstimatedTxResult(
@@ -888,7 +892,17 @@ abstract class ElectrumWalletBase
     );
 
     updatedOutputs.clear();
-    updatedOutputs.addAll(temp);
+    for (int i = 0; i < temp.length; i++) {
+      final output = temp[i];
+      final oldOutput = outputs[i];
+
+      updatedOutputs.add(BitcoinOutput(
+        address: output.address,
+        value: output.value,
+        isSilentPayment: oldOutput.isSilentPayment,
+        isChange: output.isChange,
+      ));
+    }
 
     if (fee == 0) {
       throw BitcoinTransactionNoFeeException();
@@ -1088,6 +1102,14 @@ abstract class ElectrumWalletBase
         );
       }
 
+      for (final output in updatedOutputs) {
+        // TODO: get from server
+        // if (output.isSilentPayment && output.value.toInt() > silentPaymentsMin) {
+        if (output.isSilentPayment && output.value.toInt() <= 1000) {
+          throw BitcoinTransactionNoDustException();
+        }
+      }
+
       if (walletInfo.isHardwareWallet) {
         final transaction = await buildHardwareWalletTransaction(
           utxos: estimatedTx.utxos,
diff --git a/lib/src/screens/send/widgets/send_card.dart b/lib/src/screens/send/widgets/send_card.dart
index d8b3517aa..8c372b161 100644
--- a/lib/src/screens/send/widgets/send_card.dart
+++ b/lib/src/screens/send/widgets/send_card.dart
@@ -258,7 +258,7 @@ class SendCardState extends State<SendCard> with AutomaticKeepAliveClientMixin<S
                     !sendViewModel.isBatchSending && sendViewModel.shouldDisplaySendALL,
                 currencyValueValidator: output.sendAll
                     ? sendViewModel.allAmountValidator
-                    : sendViewModel.amountValidator,
+                    : sendViewModel.amountValidator(output),
                 allAmountCallback: () async =>
                     output.setSendAll(await sendViewModel.sendingBalance),
               ),
diff --git a/lib/view_model/send/send_view_model.dart b/lib/view_model/send/send_view_model.dart
index a767065ec..22df67bf9 100644
--- a/lib/view_model/send/send_view_model.dart
+++ b/lib/view_model/send/send_view_model.dart
@@ -182,9 +182,9 @@ abstract class SendViewModelBase extends WalletChangeListenerViewModel with Stor
       if (pendingTransaction != null) {
         final currency = pendingTransactionFeeCurrency(walletType);
         final fiat = calculateFiatAmount(
-            price: _fiatConversationStore.prices[currency]!,
-            cryptoAmount: pendingTransaction!.feeFormattedValue,
-          );
+          price: _fiatConversationStore.prices[currency]!,
+          cryptoAmount: pendingTransaction!.feeFormattedValue,
+        );
         return fiat;
       } else {
         return '0.00';
@@ -210,8 +210,15 @@ abstract class SendViewModelBase extends WalletChangeListenerViewModel with Stor
 
   CryptoCurrency get currency => wallet.currency;
 
-  Validator<String> get amountValidator =>
-      AmountValidator(currency: walletTypeToCryptoCurrency(wallet.type));
+  Validator<String> amountValidator(Output output) => AmountValidator(
+        currency: walletTypeToCryptoCurrency(wallet.type),
+        minValue: isSendToSilentPayments(output)
+            ?
+            //  TODO: get from server
+            // bitcoin!.silentPaymentsMinAmount
+            '0.00001'
+            : null,
+      );
 
   Validator<String> get allAmountValidator => AllAmountValidator();
 
@@ -289,6 +296,15 @@ abstract class SendViewModelBase extends WalletChangeListenerViewModel with Stor
       // If silent payments scanning, can still send payments
       (wallet.type == WalletType.bitcoin && wallet.syncStatus is SyncingSyncStatus);
 
+  bool isSendToSilentPayments(Output output) =>
+      wallet.type == WalletType.bitcoin &&
+      (RegExp(AddressValidator.silentPaymentAddressPatternMainnet).hasMatch(output.address) ||
+          RegExp(AddressValidator.silentPaymentAddressPatternMainnet)
+              .hasMatch(output.extractedAddress) ||
+          (output.parsedAddress.addresses.isNotEmpty &&
+              RegExp(AddressValidator.silentPaymentAddressPatternMainnet)
+                  .hasMatch(output.parsedAddress.addresses[0])));
+
   @computed
   List<Template> get templates => sendTemplateViewModel.templates
       .where((template) => _isEqualCurrency(template.cryptoCurrency))