add safe network user transfer example

example/pubspec.lock

@@ -159,7 +159,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "1.2.2"
+    version: "1.2.3"
   path:
     dependency: transitive
     description:

example/safe_network_user_transfer.dart

@@ -0,0 +1,42 @@
+import 'package:mixin_bot_sdk_dart/mixin_bot_sdk_dart.dart';
+
+import 'common.dart';
+import 'safe_upgrade.dart';
+
+// the key store can from safe_upgrade.dart
+final _networkUserKeystore = KeyStore(
+  userId: "32cef966-4184-3826-9be1-77470cb6b0ec",
+  sessionId: "695775f4-76ac-4eb1-a126-1de49e110f03",
+  sessionPrivateKey:
+      "986e92602425e1d8f6a5e6a0237a0ac43c327d81579c413fd7b574b65ae75abf",
+  spendKey: "51788fd1555838e1313ccf3466b8cf95e56d25cc7e269953135e8be75576f485",
+  pinTokenBase64: "_5c1H2IKZxMWDvIN-p4BU58okomPeyWnbmlGZlUmZxU",
+);
+
+void main() async {
+  final sessionKey = Key.fromHexSeed(_networkUserKeystore.sessionPrivateKey);
+  final spendKey = Key.fromHexSeed(_networkUserKeystore.spendKey);
+
+  final userClient = Client(
+    sessionPrivateKey: sessionKey,
+    sessionId: _networkUserKeystore.sessionId,
+    userId: _networkUserKeystore.userId,
+  );
+
+  (await userClient.accountApi.getMe()).data;
+  print("spend public key: ${spendKey.publicKey().toHexString()}");
+
+  print(
+      "use Mixin Messenger scan the qrcode, and transfer to this network user");
+  print('mixin://pay/${_networkUserKeystore.userId}?asset=$cnb');
+
+  final txs = await userClient.utxoApi.transactionToUser(
+    receiverIds: ["cfb018b0-eaf7-40ec-9e07-28a5158f1269"],
+    amount: "0.01",
+    asset: cnb,
+    spendKey: spendKey,
+  );
+  for (final tx in txs) {
+    print("view tx in https://viewblock.io/mixin/tx/${tx.transactionHash}");
+  }
+}

example/safe_upgrade.dart

@@ -1,3 +1,4 @@
+import 'dart:convert';
 import 'dart:math' as math;
 import 'dart:typed_data';
 
@@ -7,10 +8,34 @@ import 'package:ed25519_edwards/ed25519_edwards.dart' as ed;
 import '../lib/mixin_bot_sdk_dart.dart';
 import 'common.dart';
 
+class KeyStore {
+  final String userId;
+  final String sessionId;
+  final String sessionPrivateKey;
+  final String spendKey;
+  final String pinTokenBase64;
+
+  KeyStore({
+    required this.userId,
+    required this.sessionId,
+    required this.sessionPrivateKey,
+    required this.spendKey,
+    required this.pinTokenBase64,
+  });
+
+  Map<String, dynamic> toJson() => {
+        "user_id": userId,
+        "session_id": sessionId,
+        "session_private_key": sessionPrivateKey,
+        "spend_key": spendKey,
+        "pin_token_base64": pinTokenBase64,
+      };
+}
+
 /// Samples for upgrade legacy pin to safe
 void main() async {
   final sessionKey = ed.generateKey();
-  print(hex.encode(sessionKey.privateKey.bytes));
+  print(hex.encode(ed.seed(sessionKey.privateKey)));
 
   final user = (await client.userApi.createUsers(
     fullName: 'User_${math.Random().nextInt(10)}',
@@ -58,4 +83,13 @@ void main() async {
   );
 
   print('account: ${account.userId} ${account.hasSafe}');
+
+  final keystore = KeyStore(
+    userId: user.userId,
+    sessionId: user.sessionId,
+    sessionPrivateKey: hex.encode(ed.seed(sessionKey.privateKey)),
+    spendKey: hex.encode(ed.seed(keyPair.privateKey)),
+    pinTokenBase64: user.pinTokenBase64,
+  );
+  print('keystore(please save it): \n${jsonEncode(keystore.toJson())}');
 }

lib/src/util/key.dart

@@ -22,6 +22,9 @@ class Key {
   factory Key.fromHexSeed(String seedInHex) =>
       Key.fromSeed(seedInHex.hexToBytes());
 
+  Uint8List publicKey() =>
+      Uint8List.fromList(ed.public(ed.PrivateKey(raw)).bytes);
+
   final Uint8List _raw;
 
   Uint8List get raw => _raw;

lib/src/util/safe.dart

@@ -283,7 +283,8 @@ String signSafeTransaction({
     final index = utxo.keys.indexOf(key.publicKey().hexString());
     if (index == -1) {
       throw Exception(
-          'invalid public key for the input: $i ${utxo.keys}, ${key.publicKey().hexString()}');
+          'invalid public key for the input: $i ${utxo.keys}, ${key.publicKey().hexString()}.\n'
+          'maybe this is a invalid spendKey: ${privateKey.publicKey().toHexString()}');
     }
     final sigs = <int, String>{};
     final sig = key.sign(msg);