Fix Windows channel tree ordering

clients/windows/VoiceCat.App/Forms/ChannelEditDialog.cs

@@ -150,8 +150,8 @@ public sealed class ChannelEditDialog : Form
         {
             Location = new Point(inputX, y - 2),
             Size = new Size(120, 23),
-            Minimum = 0,
-            Maximum = uint.MaxValue,
+            Minimum = int.MinValue,
+            Maximum = int.MaxValue,
             Value = existing?.SortOrder ?? 0,
             TabIndex = 5,
         };
@@ -385,7 +385,7 @@ public sealed class ChannelEditDialog : Form
             PasswordProtected: _chkPassword.Checked,
             Password: _chkPassword.Checked ? _txtPassword.Text : null,
             MaxUsers: (uint)_numMaxUsers.Value,
-            SortOrder: (uint)_numSortOrder.Value,
+            SortOrder: (int)_numSortOrder.Value,
             Audio: audio);
     }
 

clients/windows/VoiceCat.App/Forms/MainForm.cs

@@ -575,25 +575,21 @@ public partial class MainForm : Form
         tvChannels.BeginUpdate();
         tvChannels.Nodes.Clear();
 
-        var byParent = _channels
-            .GroupBy(c => c.ParentId)
-            .ToDictionary(g => g.Key, g => g.ToList());
-
-        void AddChildren(TreeNodeCollection nodes, uint parentId)
+        void AddChildren(TreeNodeCollection nodes, IReadOnlyList<ChannelHierarchyItem> children)
         {
-            if (!byParent.TryGetValue(parentId, out var kids)) return;
-            foreach (var ch in kids.OrderBy(c => c.Name))
+            foreach (ChannelHierarchyItem item in children)
             {
+                ChannelInfo ch = item.Channel;
                 int count = _users.Values.Count(u => u.ChannelId == ch.Id);
                 var label = $"{ch.Name} ({count})";
                 if (ch.PasswordProtected) label += " [password]";
                 if (ch.Id == _currentChannelId) label += " ►";
                 var node = new TreeNode(label) { Tag = ch.Id };
                 nodes.Add(node);
-                AddChildren(node.Nodes, ch.Id);
+                AddChildren(node.Nodes, item.Children);
             }
         }
-        AddChildren(tvChannels.Nodes, 0);
+        AddChildren(tvChannels.Nodes, ChannelHierarchy.Build(_channels));
         tvChannels.ExpandAll();
         SeekAndSelect(tvChannels.Nodes, toSelect);
         tvChannels.EndUpdate();

clients/windows/VoiceCat.Windows/Administration.cs

@@ -24,7 +24,7 @@ public sealed partial class VoiceCatClient
     }
     private static Voicecat.V1.Channel Channel(ChannelEditInfo info) => new()
     {
-        Id = info.Id, ParentId = info.ParentId, Name = info.Name, Topic = info.Topic, MaxUsers = info.MaxUsers, Order = unchecked((int)info.SortOrder),
+        Id = info.Id, ParentId = info.ParentId, Name = info.Name, Topic = info.Topic, MaxUsers = info.MaxUsers, Order = info.SortOrder,
         Audio = new() { Codec = info.Audio.Codec, Mode = info.Audio.Stereo ? ChannelMode.ModeStereo : ChannelMode.ModeMono, SampleRate = info.Audio.SampleRate,
             BitrateBps = info.Audio.BitrateBps, FrameMs = info.Audio.FrameMs, Application = (OpusApplication)info.Audio.Application, Complexity = info.Audio.Complexity,
             Fec = info.Audio.Fec, ExpectedPacketLoss = info.Audio.ExpectedPacketLoss, Dtx = info.Audio.Dtx, Dred = info.Audio.Dred }

clients/windows/VoiceCat.Windows/ChannelHierarchy.cs

@@ -0,0 +1,32 @@
+namespace VoiceCat.Windows;
+
+/// <summary>A channel and its ordered children as displayed by the Windows client.</summary>
+public sealed record ChannelHierarchyItem(
+    ChannelInfo Channel,
+    IReadOnlyList<ChannelHierarchyItem> Children);
+
+public static class ChannelHierarchy
+{
+    /// <summary>
+    /// Builds the server-defined channel hierarchy. SortOrder orders siblings; LINQ's stable
+    /// ordering preserves the server's sequence when siblings have the same value.
+    /// </summary>
+    public static IReadOnlyList<ChannelHierarchyItem> Build(IReadOnlyList<ChannelInfo> channels)
+    {
+        var byParent = channels
+            .GroupBy(channel => channel.ParentId)
+            .ToDictionary(group => group.Key, group => group.OrderBy(channel => channel.SortOrder).ToArray());
+
+        IReadOnlyList<ChannelHierarchyItem> AddChildren(uint parentId)
+        {
+            if (!byParent.TryGetValue(parentId, out ChannelInfo[]? children))
+                return [];
+
+            return children
+                .Select(channel => new ChannelHierarchyItem(channel, AddChildren(channel.Id)))
+                .ToArray();
+        }
+
+        return AddChildren(0);
+    }
+}

clients/windows/VoiceCat.Windows/Models.cs

@@ -8,7 +8,7 @@ public sealed record ChannelInfo(
     string Topic,
     bool PasswordProtected,
     uint MaxUsers,
-    uint SortOrder,
+    int SortOrder,
     AudioConfigInfo Audio);
 
 public sealed record ChannelEditInfo(
@@ -19,7 +19,7 @@ public sealed record ChannelEditInfo(
     bool PasswordProtected,
     string? Password,
     uint MaxUsers,
-    uint SortOrder,
+    int SortOrder,
     AudioConfigInfo Audio);
 
 public sealed record UserInfo(

clients/windows/VoiceCat.Windows/VoiceCatClient.cs

@@ -172,7 +172,7 @@ public sealed partial class VoiceCatClient : IDisposable
     }
     public VcResult LeaveVoice() { StopDevices(); local.Clear(); return Request(new() { UnsubscribeVoice = new() }); }
 
-    public List<ChannelInfo> ListChannels() => core.Channels.Select(c => new ChannelInfo(c.Id, c.ParentId, c.Name, c.Topic, c.PasswordProtected, c.MaxUsers, unchecked((uint)c.Order), Audio(c.Audio))).ToList();
+    public List<ChannelInfo> ListChannels() => core.Channels.Select(c => new ChannelInfo(c.Id, c.ParentId, c.Name, c.Topic, c.PasswordProtected, c.MaxUsers, c.Order, Audio(c.Audio))).ToList();
     public List<UserInfo> ListUsers() => core.Users.Select(u => new UserInfo(u.Id, u.Nickname, u.IsGuest, u.ChannelId, u.SelfMicMuted, u.SelfDeafened, u.ServerMuted, u.ServerDeafened, u.VoiceSubscribed)).ToList();
     public List<StreamSummary> ListUserStreams(uint id) => id == core.Authentication?.Self.Id
         ? local.Values.Select(s => new StreamSummary(s.Alias, (VcStreamKind)s.Info.Kind, s.Info.Label)).ToList()

tests/VoiceCat.Tests/WindowsManagedClientTests.cs

@@ -8,6 +8,28 @@ namespace VoiceCat.Tests;
 
 public class WindowsManagedClientTests
 {
+    private static readonly AudioConfigInfo DefaultAudio = new(0, false, 48_000, 64_000, 20, 0, true, 10, false, 10, false);
+
+    [Fact]
+    public void ChannelHierarchyUsesServerSortOrderAndKeepsIdsWithDisplayedChannels()
+    {
+        ChannelInfo[] channels =
+        [
+            new(10, 0, "Zulu", "", false, 0, -10, DefaultAudio),
+            new(20, 0, "Alpha", "", false, 0, 20, DefaultAudio),
+            new(11, 10, "Zulu child", "", false, 0, 10, DefaultAudio),
+            new(12, 10, "Alpha child", "", false, 0, 0, DefaultAudio),
+            new(30, 0, "Beta", "", false, 0, 20, DefaultAudio),
+        ];
+
+        IReadOnlyList<ChannelHierarchyItem> roots = ChannelHierarchy.Build(channels);
+
+        Assert.Equal([(10U, "Zulu"), (20U, "Alpha"), (30U, "Beta")],
+            roots.Select(item => (item.Channel.Id, item.Channel.Name)));
+        Assert.Equal([(12U, "Alpha child"), (11U, "Zulu child")],
+            roots[0].Children.Select(item => (item.Channel.Id, item.Channel.Name)));
+    }
+
     private static async Task Until(Client client, Func<bool> predicate)
     {
         using var timeout = new CancellationTokenSource(TimeSpan.FromSeconds(10));