From c35a4e31cca0694eb18db3d3b87b0e63569afdbc Mon Sep 17 00:00:00 2001
From: BigtoC <taitocdt@gmail.com>
Date: Sun, 20 Jul 2025 14:55:06 +0800
Subject: [PATCH] feat(wallet): Add Ethereum address conversion to Bech32
 format

---
 lib/application/wallet/utils.dart       | 52 +++++++++++++++++++++++++
 lib/application/wallet/wallet_bloc.dart |  9 +++++
 2 files changed, 61 insertions(+)
 create mode 100644 lib/application/wallet/utils.dart

diff --git a/lib/application/wallet/utils.dart b/lib/application/wallet/utils.dart
new file mode 100644
index 0000000..c4cf029
--- /dev/null
+++ b/lib/application/wallet/utils.dart
@@ -0,0 +1,52 @@
+import "package:blockchain_utils/bech32/bech32_base.dart";
+import "package:blockchain_utils/bip/address/addr_dec_utils.dart";
+import "package:blockchain_utils/bip/address/eth_addr.dart";
+import "package:blockchain_utils/bip/coin_conf/constant/coins_conf.dart";
+import "package:blockchain_utils/hex/hex.dart";
+
+class EthBech32Converter {
+  /// Encodes an Ethereum address in Bech32 format.
+  /// This method takes a hexadecimal Ethereum address and a prefix,
+  /// converts the address to bytes, and then encodes to Bech32-format address.
+  ///
+  /// Parameters:
+  ///   - hexAddress: The hexadecimal representation of the Ethereum address.
+  ///   - prefix: The Bech32 prefix to be used for encoding.
+  ///
+  /// Returns:
+  ///   A Bech32-encoded address.
+  ///
+  /// Throws:
+  ///  - AssertionError: If the length of the cleaned hexadecimal address is not equal to the expected Ethereum address length.
+  static String ethAddressToBech32(String ethAddress, prefix) {
+
+    final cleanHex = AddrDecUtils.validateAndRemovePrefix(
+        ethAddress, CoinsConf.ethereum.params.addrPrefix!
+    );
+    assert(
+    cleanHex.length == EthAddrConst.addrLen,
+    "Invalid Ethereum address length: ${cleanHex.length}, expected: ${EthAddrConst.addrLen}"
+    );
+    final hexAddressBytes = hex.decode(cleanHex);
+    return Bech32Encoder.encode(prefix, hexAddressBytes);
+  }
+
+  /// Decodes a Bech32-encoded address.
+  /// This method takes a Bech32-encoded address
+  /// and decodes it to its hexadecimal representation.
+  ///
+  /// Parameters:
+  ///   - bech32Address: The Bech32-encoded Ethereum address.
+  ///
+  /// Returns:
+  ///   A string representing the Ethereum address.
+  static String bech32ToEthAddress(String bech32Address, prefix) {
+    final decoded = Bech32Decoder.decode(prefix, bech32Address);
+    final hexEncoded = hex.encode(decoded);
+    assert(
+    hexEncoded.length == EthAddrConst.addrLen,
+    "Invalid Ethereum address length: ${hexEncoded.length}, expected: ${EthAddrConst.addrLen}"
+    );
+    return "${CoinsConf.ethereum.params.addrPrefix!}$hexEncoded";
+  }
+}
diff --git a/lib/application/wallet/wallet_bloc.dart b/lib/application/wallet/wallet_bloc.dart
index 899b900..8717f3a 100644
--- a/lib/application/wallet/wallet_bloc.dart
+++ b/lib/application/wallet/wallet_bloc.dart
@@ -1,5 +1,7 @@
 import "package:cosmos_sdk/cosmos_sdk.dart";
+import "package:hnotes/application/wallet/utils.dart";
 import "package:hnotes/infrastructure/blockchain/wallet_repository.dart";
+import "package:hnotes/infrastructure/constants.dart";
 import "package:hnotes/infrastructure/local_storage/secrets/secrets_repository.dart";
 import "package:rxdart/rxdart.dart";
 
@@ -40,6 +42,13 @@ class WalletBloc {
       String receiver,
       {TransactionConfirmationCallback? confirmTransaction}
       ) async {
+    if (receiver.startsWith("0x")) {
+      receiver = EthBech32Converter.ethAddressToBech32(
+          receiver,
+          chainAddressPrefix
+      );
+    }
+
     final message = MsgSend(
         fromAddress: CosmosBaseAddress(sender),
         toAddress: CosmosBaseAddress(receiver),