feat: fix safe final sig encoding

example/lib/providers/wallet_provider.dart

@@ -1,6 +1,7 @@
 import 'dart:convert';
 import 'dart:developer';
 import 'dart:io';
+import 'dart:math' as math;
 import 'package:flutter/foundation.dart';
 import 'package:web3_signers/web3_signers.dart';
 import 'package:variance_dart/variance.dart';
@@ -53,33 +54,36 @@ class WalletProvider extends ChangeNotifier {
     }
   }
 
-  Future<void> registerWithHDWallet() async {
+  Future<void> createSafeWallet() async {
+    _chain.accountFactory = Constants.safeProxyFactoryAddress;
+
     final signer = EOAWallet.createWallet();
-    log("mnemonic: ${signer.exportMnemonic()}");
+    log("signer: ${signer.getAddress()}");
 
     final SmartWalletFactory walletFactory = SmartWalletFactory(_chain, signer);
 
-    final salt = Uint256.fromHex(hexlify(w3d.keccak256(
-        Uint8List.fromList(utf8.encode(signer.getAddress().substring(2))))));
+    final salt = Uint256.fromHex(hexlify(w3d
+        .keccak256(EthereumAddress.fromHex(signer.getAddress()).addressBytes)));
 
-    _chain.accountFactory = Constants.safeProxyFactoryAddress;
-    final safe = await walletFactory.createSafeAccount(salt);
-    log("safe created ${safe.address.hex} ");
+    log("salt: ${salt.toHex()}");
 
     try {
-      _chain.accountFactory = Constants.simpleAccountFactoryAddress;
-      _wallet = await walletFactory.createSimpleAccount(salt);
-      log("wallet created ${_wallet?.address.hex} ");
+      _wallet = await walletFactory.createSafeAccount(salt);
+      log("safe created ${_wallet?.address.hex} ");
     } catch (e) {
       log("something happened: $e");
     }
   }
 
   Future<void> sendTransaction(String recipient, String amount) async {
     if (_wallet != null) {
-      final etherAmount =
-          w3d.EtherAmount.fromBase10String(w3d.EtherUnit.ether, amount);
-      await _wallet!.send(EthereumAddress.fromHex(recipient), etherAmount);
+      final etherAmount = w3d.EtherAmount.fromBigInt(w3d.EtherUnit.wei,
+          BigInt.from(double.parse(amount) * math.pow(10, 18)));
+      final response =
+          await _wallet!.send(EthereumAddress.fromHex(recipient), etherAmount);
+      final receipt = await response.wait();
+
+      log("Transaction receipt Hash: ${receipt?.userOpHash}");
     } else {
       log("No wallet available to send transaction");
     }

example/lib/screens/create_account.dart

@@ -112,16 +112,14 @@ class _CreateAccountScreenState extends State<CreateAccountScreen> {
                     child: TextButton.icon(
                         onPressed: () {
                           try {
-                            context
-                                .read<WalletProvider>()
-                                .registerWithHDWallet();
+                            context.read<WalletProvider>().createSafeWallet();
                             Navigator.pushNamed(context, '/home');
                           } catch (e) {
                             'Something went wrong: $e';
                           }
                         },
                         icon: const Icon(Icons.key),
-                        label: const Text('Generate Account with HD Key')),
+                        label: const Text('Create Safe Smart Account')),
                   )
                 ],
               ),

lib/src/4337/chains.dart

@@ -125,7 +125,7 @@ class Chains {
       entrypoint: EntryPointAddress.v06,
     ),
     Network.baseTestent: Chain(
-      chainId: 84531,
+      chainId: 84532,
       explorer: "https://sepolia.basescan.org/",
       jsonRpcUrl: "https://rpc.ankr.com/base_sepolia",
       entrypoint: EntryPointAddress.v06,

lib/src/4337/providers.dart

@@ -22,7 +22,7 @@ class BundlerProvider implements BundlerProviderBase {
         .send<String>('eth_chainId')
         .then(BigInt.parse)
         .then((value) => value.toInt() == chain.chainId)
-        .then((value) => _initialized = value == true);
+        .then((value) => _initialized = value);
   }
 
   /// A flag indicating whether the initialization process was successful.

lib/src/4337/safe.dart

@@ -17,9 +17,11 @@ class _SafePlugin extends Safe4337Module implements Safe4337ModuleBase {
   /// Computes the hash of a Safe UserOperation.
   ///
   /// [op] is an object representing the user operation details.
+  /// [currentTimestamp] is the current timestamp in seconds.
   ///
   /// Returns a Future that resolves to the hash of the user operation as a Uint8List.
-  Future<Uint8List> getUserOperationHash(UserOperation op) async =>
+  Future<Uint8List> getUserOperationHash(
+          UserOperation op, int currentTimestamp) async =>
       getOperationHash([
         op.sender,
         op.nonce,
@@ -31,23 +33,22 @@ class _SafePlugin extends Safe4337Module implements Safe4337ModuleBase {
         op.maxFeePerGas,
         op.maxPriorityFeePerGas,
         op.paymasterAndData,
-        _getEncodedSignature(op.signature)
+        hexToBytes(getEncodedSignature(op.signature, currentTimestamp))
       ]);
 
   /// Encodes the signature of a user operation with a validity period.
   ///
   /// [signature] is the signature of the user operation.
+  /// [currentTimestamp] is the current timestamp in seconds.
   ///
-  /// Returns a Uint8List representing the encoded signature with a validity period.
-  Uint8List _getEncodedSignature(String signature) {
-    final currentTimestamp = DateTime.now().millisecondsSinceEpoch ~/ 1000;
-
+  /// Returns a HexString representing the encoded signature with a validity period.
+  String getEncodedSignature(String signature, int currentTimestamp) {
     String validAfter = currentTimestamp.toRadixString(16);
     validAfter = '0' * (12 - validAfter.length) + validAfter;
 
     String validUntil = (currentTimestamp + 3600).toRadixString(16);
     validUntil = '0' * (12 - validUntil.length) + validUntil;
 
-    return hexToBytes('0x$validAfter$validUntil${signature.substring(2)}');
+    return '0x$validAfter$validUntil${signature.substring(2)}';
   }
 }

lib/src/4337/wallet.dart

@@ -153,16 +153,26 @@ class SmartWallet with _PluginManager, _GasSettings implements SmartWalletBase {
   @override
   Future<UserOperation> signUserOperation(UserOperation op,
       {int? index}) async {
-    // Calculate the operation hash. safe accounts uses EIP712
-    // The hash is retrieved by calling the SafeModule with the operation and a dummy signature.
-    final opHash = hasPlugin("safe")
-        ? await plugin<_SafePlugin>("safe").getUserOperationHash(op)
+    final isSafe = hasPlugin('safe');
+    final currentTimestamp = DateTime.now().millisecondsSinceEpoch ~/ 1000;
+
+    // Calculate the operation hash
+    final opHash = isSafe
+        ? await plugin<_SafePlugin>('safe')
+            .getUserOperationHash(op, currentTimestamp)
         : op.hash(_chain);
 
     // Sign the operation hash using the 'signer' plugin
-    Uint8List signature =
+    final signature =
         await plugin<MSI>('signer').personalSign(opHash, index: index);
-    op.signature = hexlify(signature);
+    final signatureHex = hexlify(signature);
+
+    // Append the signature validity period if the 'safe' plugin is enabled
+    op.signature = isSafe
+        ? plugin<_SafePlugin>('safe')
+            .getEncodedSignature(signatureHex, currentTimestamp)
+        : signatureHex;
+
     return op;
   }
 
@@ -193,7 +203,7 @@ class SmartWallet with _PluginManager, _GasSettings implements SmartWalletBase {
       ]).then((responses) {
         op = op.copyWith(
             nonce: op.nonce > BigInt.zero ? op.nonce : responses[0].value,
-            initCode: responses[0] > BigInt.zero ? Uint8List(0) : null,
+            initCode: responses[0].value > BigInt.zero ? Uint8List(0) : null,
             signature: dummySignature);
         return _updateUserOperationGas(op, feePerGas: responses[1]);
       });

lib/src/common/logger.dart

@@ -1,3 +1,5 @@
+import 'dart:developer';
+
 /// A class that provides logging functionality with colored output for warnings and errors.
 class Logger {
   /// The ANSI escape code for red color.
@@ -66,7 +68,7 @@ class Logger {
   /// [stackTrace] is an optional stack trace associated with the error message.
   static void _logError(String level, String color, String message,
       [Object? error, StackTrace? stackTrace]) {
-    String errorMessage = '$message';
+    String errorMessage = message;
     if (error != null) {
       errorMessage += '\nError: $error';
     }
@@ -91,6 +93,6 @@ class Logger {
         '${now.second.toString().padLeft(2, '0')}';
 
     final logMessage = '$formattedTime [$color$level$_resetColor] $message';
-    print(logMessage);
+    log(logMessage);
   }
 }

lib/variance.dart

@@ -3,6 +3,7 @@ library;
 import 'dart:async';
 import 'dart:convert';
 import 'dart:isolate';
+import 'dart:developer';
 import 'dart:typed_data';
 
 import 'package:http/http.dart' as http;