From 3f2f592593efe306f85fb0e81ce07aa1ea90b7b6 Mon Sep 17 00:00:00 2001
From: Dominik Toton <166132265+dtscalac@users.noreply.github.com>
Date: Mon, 2 Sep 2024 14:21:13 +0200
Subject: [PATCH] fix: catalyst cardano null utxos (#746)

* fix: handle null utxos

* fix: more error logs
---
 .../example/lib/sign_and_submit_rbac_tx.dart  |  4 +++
 .../example/lib/sign_and_submit_tx.dart       |  4 +++
 .../src/interop/catalyst_cardano_interop.dart |  2 +-
 .../catalyst_cardano_wallet_proxy.dart        | 35 ++++++++++---------
 4 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_rbac_tx.dart b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_rbac_tx.dart
index e4ca17c1db1..ccd16f05746 100644
--- a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_rbac_tx.dart
+++ b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_rbac_tx.dart
@@ -80,6 +80,10 @@ Future<void> _signAndSubmitRbacTx({
       ),
     );
 
+    if (utxos.isEmpty) {
+      throw Exception('Insufficient balance, please top up your wallet');
+    }
+
     final x509Envelope = await _buildMetadataEnvelope(
       utxos: utxos,
     );
diff --git a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_tx.dart b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_tx.dart
index 22bdc078912..a51e7ea4b33 100644
--- a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_tx.dart
+++ b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano/example/lib/sign_and_submit_tx.dart
@@ -14,6 +14,10 @@ Future<void> _signAndSubmitTx({
       ),
     );
 
+    if (utxos.isEmpty) {
+      throw Exception('Insufficient balance, please top up your wallet');
+    }
+
     final unsignedTx = _buildUnsignedTx(
       utxos: utxos,
       changeAddress: changeAddress,
diff --git a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_interop.dart b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_interop.dart
index 835fceff1d9..43fbaafc34b 100644
--- a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_interop.dart
+++ b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_interop.dart
@@ -73,7 +73,7 @@ extension type JSCardanoWalletApi(JSObject _) implements JSObject {
   ]);
 
   /// See [CardanoWalletApi.getUtxos].
-  external JSPromise<JSArray<JSString>> getUtxos([
+  external JSPromise<JSArray<JSString>>? getUtxos([
     JSAny? amount,
     JSAny? paginate,
   ]);
diff --git a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_wallet_proxy.dart b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_wallet_proxy.dart
index ce14d5775c2..573ba46361b 100644
--- a/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_wallet_proxy.dart
+++ b/catalyst_voices_packages/catalyst_cardano/catalyst_cardano_web/lib/src/interop/catalyst_cardano_wallet_proxy.dart
@@ -176,23 +176,24 @@ class JSCardanoWalletApiProxy implements CardanoWalletApi {
     Paginate? paginate,
   }) async {
     try {
-      return await _delegate
-          .getUtxos(
-            amount != null
-                ? hex.encode(cbor.encode(amount.toCbor())).toJS
-                : makeUndefined(),
-            paginate != null ? JSPaginate.fromDart(paginate) : makeUndefined(),
-          )
-          .toDart
-          .then(
-            (array) => array.toDart
-                .map(
-                  (item) => TransactionUnspentOutput.fromCbor(
-                    cbor.decode(hex.decode(item.toDart)),
-                  ),
-                )
-                .toList(),
-          );
+      final utxos = _delegate.getUtxos(
+        amount != null
+            ? hex.encode(cbor.encode(amount.toCbor())).toJS
+            : makeUndefined(),
+        paginate != null ? JSPaginate.fromDart(paginate) : makeUndefined(),
+      );
+
+      if (utxos == null) return [];
+
+      return await utxos.toDart.then(
+        (array) => array.toDart
+            .map(
+              (item) => TransactionUnspentOutput.fromCbor(
+                cbor.decode(hex.decode(item.toDart)),
+              ),
+            )
+            .toList(),
+      );
     } catch (ex) {
       throw _mapApiException(ex) ??
           _mapPaginateException(ex) ??