Merge pull request #25 from reown-com/fix/metamask-chain-switch

fix: chain switching not working in mobile MM

Reown.sln

@@ -36,6 +36,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Reown.WalletKit.Test", "tes
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Reown.Core.Storage.Test", "test\Reown.Core.Storage.Test\Reown.Core.Storage.Test.csproj", "{F13FA074-D00C-46B9-A7AC-78FCF940165D}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Reown.Core.Common.Test", "test\Reown.Core.Common.Test\Reown.Core.Common.Test.csproj", "{4C513826-A313-40FA-A6ED-F74A33139809}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -114,5 +116,9 @@ Global
 		{F13FA074-D00C-46B9-A7AC-78FCF940165D}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{F13FA074-D00C-46B9-A7AC-78FCF940165D}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{F13FA074-D00C-46B9-A7AC-78FCF940165D}.Release|Any CPU.Build.0 = Release|Any CPU
+		{4C513826-A313-40FA-A6ED-F74A33139809}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{4C513826-A313-40FA-A6ED-F74A33139809}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{4C513826-A313-40FA-A6ED-F74A33139809}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{4C513826-A313-40FA-A6ED-F74A33139809}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal

src/Reown.AppKit.Unity/Runtime/Controllers/NetworkController/NetworkControllerCore.cs

@@ -20,11 +20,19 @@ protected override Task InitializeAsyncCore(IEnumerable<Chain> supportedChains)
         protected override async Task ChangeActiveChainAsyncCore(Chain chain)
         {
             if (AppKit.ConnectorController.IsAccountConnected)
+            {
                 // Request connector to change active chain.
                 // If connector approves the change, it will trigger the ChainChanged event.
                 await AppKit.ConnectorController.ChangeActiveChainAsync(chain);
+
+                var previousChain = ActiveChain;
+                ActiveChain = chain;
+                OnChainChanged(new ChainChangedEventArgs(previousChain, chain));
+            }
             else
+            {
                 ActiveChain = chain;
+            }
 
             AppKit.EventsController.SendEvent(new Event
             {
@@ -38,6 +46,9 @@ protected override async Task ChangeActiveChainAsyncCore(Chain chain)
 
         protected override void ConnectorChainChangedHandlerCore(object sender, Connector.ChainChangedEventArgs e)
         {
+            if (ActiveChain?.ChainId == e.ChainId)
+                return;
+
             var chain = Chains.GetValueOrDefault(e.ChainId);
 
             var previousChain = ActiveChain;

src/Reown.Core.Common/Runtime/Utils/HexByteConvertorExtensions.cs

@@ -1,25 +1,105 @@
 using System;
 using System.Linq;
+using System.Numerics;
 using System.Text;
 
 namespace Reown.Core.Common.Utils
 {
-    //From article http://blogs.msdn.com/b/heikkiri/archive/2012/07/17/hex-string-to-corresponding-byte-array.aspx
     public static class HexByteConvertorExtensions
     {
         private static readonly byte[] Empty = Array.Empty<byte>();
 
         public static string ToHex(this byte[] value, bool prefix = false)
         {
-            var strPrex = prefix ? "0x" : "";
-            return strPrex + string.Concat(value.Select(b => b.ToString("x2")).ToArray());
+            var prefixLength = prefix ? 2 : 0;
+            var bufferLength = prefixLength + value.Length * 2; // Each byte becomes two hex characters
+
+            var buffer = bufferLength <= 256
+                ? stackalloc char[bufferLength]
+                : new char[bufferLength];
+
+            var index = 0;
+            if (prefix)
+            {
+                buffer[0] = '0';
+                buffer[1] = 'x';
+                index = 2;
+            }
+
+            foreach (var b in value)
+            {
+                buffer[index++] = GetHexChar(b >> 4); // High nibble
+                buffer[index++] = GetHexChar(b & 0x0F); // Low nibble
+            }
+
+            return new string(buffer);
         }
 
         public static string ToHex(this string value, bool prefix = false)
         {
             return ToHex(Encoding.UTF8.GetBytes(value), prefix);
         }
 
+        public static string ToHex(this int value, bool prefix = false)
+        {
+            Span<char> buffer = stackalloc char[10]; // 8 characters for the value + 2 for the prefix
+
+            var index = 0;
+            if (prefix)
+            {
+                buffer[0] = '0';
+                buffer[1] = 'x';
+                index = 2;
+            }
+
+            var success = value.TryFormat(buffer[index..], out var charsWritten, "x");
+
+            if (!success)
+            {
+                throw new InvalidOperationException("Failed to convert value to hex");
+            }
+
+            return new string(buffer[..(index + charsWritten)]);
+        }
+
+        public static string ToHex(this BigInteger value, bool prefix = false)
+        {
+            if (value.IsZero)
+                return prefix ? "0x0" : "0";
+
+            var byteCount = value.GetByteCount();
+            var prefixLength = prefix ? 2 : 0;
+            var bufferLength = prefixLength + byteCount * 2; // Each byte becomes two hex characters
+
+            var buffer = bufferLength <= 256
+                ? stackalloc char[bufferLength]
+                : new char[bufferLength];
+
+            var success = value.TryFormat(buffer, out var charsWritten, "x");
+            if (!success)
+            {
+                throw new InvalidOperationException("Failed to convert value to hexadecimal.");
+            }
+
+            // Remove unnecessary leading zeros
+            var nonZeroStartIndex = 0;
+            while (nonZeroStartIndex < charsWritten && buffer[nonZeroStartIndex] == '0')
+                nonZeroStartIndex++;
+
+            if (nonZeroStartIndex == charsWritten)
+                return prefix ? "0x0" : "0";
+
+            if (!prefix)
+                return new string(buffer.Slice(nonZeroStartIndex, charsWritten - nonZeroStartIndex));
+
+            var resultLength = charsWritten - nonZeroStartIndex;
+            var resultBuffer = bufferLength <= 256 ? stackalloc char[2 + resultLength] : new char[2 + resultLength];
+            resultBuffer[0] = '0';
+            resultBuffer[1] = 'x';
+            buffer.Slice(nonZeroStartIndex, resultLength).CopyTo(resultBuffer[2..]);
+            return new string(resultBuffer);
+        }
+
         public static bool HasHexPrefix(this string value)
         {
             return value.StartsWith("0x");
@@ -128,10 +208,16 @@ public static byte[] HexToByteArray(this string value)
             }
         }
 
+        // Maps 0-15 to '0'-'9' and 'a'-'f'
+        private static char GetHexChar(int value)
+        {
+            return (char)(value < 10 ? '0' + value : 'a' + (value - 10));
+        }
+
         private static byte FromCharacterToByte(char character, int index, int shift = 0)
         {
             var value = (byte)character;
-            if (0x40 < value && 0x47 > value || 0x60 < value && 0x67 > value)
+            if (value is > 0x40 and < 0x47 or > 0x60 and < 0x67)
             {
                 if (0x40 == (0x40 & value))
                     if (0x20 == (0x20 & value))

src/Reown.Sign.Nethereum/Runtime/Extensions.cs

@@ -1,10 +1,9 @@
 using System;
 using System.Linq;
 using System.Threading.Tasks;
-using Newtonsoft.Json.Linq;
+using Newtonsoft.Json;
 using Reown.Core.Common.Model.Errors;
 using Reown.Sign.Interfaces;
-using Reown.Sign.Models.Engine.Methods;
 using Reown.Sign.Nethereum.Model;
 
 namespace Reown.Sign.Nethereum
@@ -22,60 +21,34 @@ public static async Task SwitchEthereumChainAsync(this ISignClient signClient, E
             if (ethereumChain == null)
                 throw new ArgumentNullException(nameof(ethereumChain));
 
-            var tcs = new TaskCompletionSource<bool>();
-            signClient.SubscribeToSessionEvent("chainChanged", OnChainChanged);
-
             var caip2ChainId = $"eip155:{ethereumChain.chainIdDecimal}";
             if (!signClient.AddressProvider.DefaultSession.Namespaces.TryGetValue("eip155", out var @namespace)
                 || !@namespace.Chains.Contains(caip2ChainId))
             {
-                var request = new WalletAddEthereumChain(ethereumChain);
-
                 try
                 {
-                    await signClient.Request<WalletAddEthereumChain, string>(request);
-
+                    // Try to switch chain. This will only work if the chain is already added to the MetaMask
                     var data = new WalletSwitchEthereumChain(ethereumChain.chainIdHex);
-
-                    var switchChainTask = signClient.Request<WalletSwitchEthereumChain, string>(data);
-                    var chainChangedEventTask = tcs.Task;
-
+                    await signClient.Request<WalletSwitchEthereumChain, string>(data);
+                }
+                catch (ReownNetworkException e)
+                {
                     try
                     {
-                        await Task.WhenAll(switchChainTask, chainChangedEventTask);
+                        var metaMaskError = JsonConvert.DeserializeObject<MetaMaskError>(e.Message);
+                        if (metaMaskError is { Code: 4001 }) // If user rejected
+                            throw;
                     }
-                    finally
+                    catch (Exception)
                     {
-                        _ = signClient.TryUnsubscribeFromSessionEvent("chainChanged", OnChainChanged);
+                        // If requested chain is not added to the MetaMask, it returns an error that can't be deserialized
                     }
-                }
-                catch (ReownNetworkException)
-                {
-                    // Wallet can decline if chain has already been added
-                }
-            }
-
-            async void OnChainChanged(object sender, SessionEvent<JToken> sessionEvent)
-            {
-                if (sessionEvent.ChainId == "eip155:0")
-                    return;
-
-                if (sessionEvent.ChainId != $"eip155:{ethereumChain.chainIdDecimal}")
-                    return;
-
-                // Wait for the session to be updated before changing the default chain id
-                await Task.Delay(TimeSpan.FromSeconds(1));
 
-                try
-                {
-                    await signClient.AddressProvider.SetDefaultChainIdAsync(sessionEvent.ChainId);
-                }
-                catch (Exception e)
-                {
-                    tcs.SetException(e);
+                    // If the chain is not added to the MetaMask, add it
+                    // MetaMask will also prompt the user to switch to the new chain
+                    var request = new WalletAddEthereumChain(ethereumChain);
+                    await signClient.Request<WalletAddEthereumChain, string>(request);
                 }
-
-                tcs.SetResult(true);
             }
         }
     }

src/Reown.Sign.Nethereum/Runtime/Model/EthereumChain.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Numerics;
 using Newtonsoft.Json;
 using Reown.Core.Common.Utils;
 
@@ -33,7 +34,7 @@ public EthereumChain()
         public EthereumChain(string chainIdDecimal, string name, in Currency nativeCurrency, string[] rpcUrls, string[] blockExplorerUrls = null)
         {
             this.chainIdDecimal = chainIdDecimal;
-            chainIdHex = chainIdDecimal.ToHex();
+            chainIdHex = BigInteger.Parse(chainIdDecimal).ToHex(true);
             this.name = name;
             this.nativeCurrency = nativeCurrency;
             this.rpcUrls = rpcUrls;

src/Reown.Sign.Nethereum/Runtime/Model/MetaMaskError.cs

@@ -0,0 +1,15 @@
+using System;
+using Newtonsoft.Json;
+
+namespace Reown.Sign.Nethereum.Model
+{
+    [Serializable]
+    public class MetaMaskError
+    {
+        [JsonProperty("code")]
+        public int Code { get; set; }
+
+        [JsonProperty("message")]
+        public string Message { get; set; }
+    }
+}

test/Reown.Core.Common.Test/HexByteConvertorExtensionsTests.cs

@@ -0,0 +1,29 @@
+using System.Numerics;
+using Reown.Core.Common.Utils;
+using Xunit;
+
+namespace Reown.Core.Common.Test;
+
+public class HexByteConvertorExtensionsTests
+{
+    [Theory]
+    [InlineData(137, true, "0x89")]
+    [InlineData(16, true, "0x10")]
+    [InlineData(256, true, "0x100")]
+    [InlineData(0, true, "0x0")]
+    [InlineData(1, true, "0x1")]
+    [InlineData(4096, true, "0x1000")]
+    [InlineData(37714555429, true, "0x8c7f67225")]
+    [InlineData(137, false, "89")]
+    [InlineData(16, false, "10")]
+    [InlineData(256, false, "100")]
+    [InlineData(0, false, "0")]
+    [InlineData(1, false, "1")]
+    [InlineData(4096, false, "1000")]
+    [InlineData(37714555429, false, "8c7f67225")]
+    public void ToHex_Values_ReturnsExpectedHex(BigInteger value, bool prefix, string expected)
+    {
+        var result = value.ToHex(prefix);
+        Assert.Equal(expected, result);
+    }
+}

test/Reown.Core.Common.Test/Reown.Core.Common.Test.csproj

@@ -0,0 +1,24 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net8.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+
+        <IsPackable>false</IsPackable>
+        <IsTestProject>true</IsTestProject>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="Microsoft.NET.Test.Sdk"/>
+        <PackageReference Include="xunit"/>
+        <PackageReference Include="xunit.runner.visualstudio">
+            <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+            <PrivateAssets>all</PrivateAssets>
+        </PackageReference>
+    </ItemGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\..\src\Reown.Core.Common\Reown.Core.Common.csproj" />
+    </ItemGroup>
+</Project>