refactor(fonts): hybrid FontManager init via SuppressAutoRebuild

Move font handle creation from BuildFonts() into the FontManager ctor
inside a single atlas.SuppressAutoRebuild() block. Axis, AxisItalic and
FontAwesome become init-only IFontHandle properties; RegularFont and
ItalicFont stay mutable so the live font-settings rebuild path keeps
working without a plugin reload.

- BuildFonts() renamed to RebuildDelegateFonts(), scope reduced to the
  delegate fonts only
- BuildFontsAsync() removed; Task.Run had no purpose with ctor-init
- FontManagerInitHostedService deleted; PluginHostFactory drops the
  matching AddHostedService registration
- PluginHostFactory FontManager registration takes IDalamudPluginInterface
  via factory lambda
- Settings save path now calls RebuildDelegateFonts() instead of
  BuildFonts()
- Plugin.Draw push site gets a null-forgiving for the nullable
  RegularFont with a one-line WHY

HellionChat/FontManager.cs

@@ -1,26 +1,42 @@
-using Dalamud;
+using Dalamud;
 using Dalamud.Bindings.ImGui;
 using Dalamud.Interface;
 using Dalamud.Interface.FontIdentifier;
 using Dalamud.Interface.GameFonts;
 using Dalamud.Interface.ManagedFontAtlas;
 using Dalamud.Interface.Utility;
+using Dalamud.Plugin;
 
 namespace HellionChat;
 
 // Two LogProxy sites live in static methods (TryGetHellionFontBytes,
 // AddFontWithFallback); a ctor-injected ILogger would not be reachable
 // from those scopes, so the class stays on Plugin.LogProxy.
-public class FontManager
+//
+// Hybrid handle model: Axis, AxisItalic and FontAwesome are tied to the
+// game's current font state and never change for the lifetime of the
+// plugin, so they are init-only. RegularFont and ItalicFont depend on
+// user-toggleable settings and get replaced live via RebuildDelegateFonts
+// when those settings change; they stay as mutable nullable fields.
+//
+// All five handles register inside a single SuppressAutoRebuild block in
+// the ctor so the font atlas only rebuilds once for the whole plugin start
+// instead of once per handle.
+public sealed class FontManager : IDisposable
 {
-    internal IFontHandle Axis = null!;
+    private readonly IDalamudPluginInterface _pluginInterface;
-    internal IFontHandle AxisItalic = null!;
 
-    internal IFontHandle RegularFont = null!;
+    internal IFontHandle Axis { get; init; }
+    internal IFontHandle AxisItalic { get; init; }
+    internal IFontHandle FontAwesome { get; init; }
+
+    // Mutable because the live font settings replace these via
+    // RebuildDelegateFonts. Reference replacement is atomic for reference
+    // types, so push sites that read the field once per frame see at most
+    // one stale handle.
+    internal IFontHandle? RegularFont;
     internal IFontHandle? ItalicFont;
 
-    internal IFontHandle FontAwesome = null!;
-
     private ushort[] Ranges = [];
     private ushort[] JpRange = [];
 
@@ -47,10 +63,133 @@ public class FontManager
     // Hellion font bytes (Exo 2, OFL-1.1); lazily loaded from manifest resources
     private static byte[]? HellionFontBytes;
 
-    // Returns null when the embedded font resource is missing. Should never
+    public FontManager(IDalamudPluginInterface pluginInterface)
+    {
+        _pluginInterface = pluginInterface;
+        SetUpRanges();
+
+        var atlas = _pluginInterface.UiBuilder.FontAtlas;
+
+        using (atlas.SuppressAutoRebuild())
+        {
+            Axis = atlas.NewGameFontHandle(
+                new GameFontStyle(GameFontFamily.Axis, SizeInPx(Plugin.Config.FontSizeV2))
+            );
+
+            AxisItalic = atlas.NewGameFontHandle(
+                new GameFontStyle(GameFontFamily.Axis, SizeInPx(Plugin.Config.FontSizeV2))
+                {
+                    SkewStrength = SizeInPx(Plugin.Config.FontSizeV2) / 6,
+                }
+            );
+
+            FontAwesome = atlas.NewDelegateFontHandle(e =>
+            {
+                e.OnPreBuild(tk =>
+                    tk.AddFontAwesomeIconFont(new SafeFontConfig { SizePx = GetFontSize() })
+                );
+                e.OnPostBuild(tk => tk.FitRatio(tk.Font));
+            });
+
+            RegularFont = BuildRegularFontHandle(atlas);
+
+            if (Plugin.Config.ItalicEnabled)
+                ItalicFont = BuildItalicFontHandle(atlas);
+        }
+    }
+
+    // Called from the settings save path when one of the font-related
+    // settings changed. Game fonts and FontAwesome stay untouched because
+    // none of those settings affect them.
+    //
+    // Thread model: the settings save path runs on the ImGui draw thread,
+    // same as every push site. The rebuild finishes synchronously before
+    // the next push reads the field in the same frame, so there is no
+    // cross-thread race on the handle reference.
+    public void RebuildDelegateFonts()
+    {
+        SetUpRanges();
+
+        var atlas = _pluginInterface.UiBuilder.FontAtlas;
+
+        RegularFont?.Dispose();
+        RegularFont = BuildRegularFontHandle(atlas);
+
+        ItalicFont?.Dispose();
+        ItalicFont = Plugin.Config.ItalicEnabled ? BuildItalicFontHandle(atlas) : null;
+    }
+
+    // Instance method so Ranges / JpRange are reachable without parameter
+    // plumbing; PascalCase field names follow the existing class style.
+    private IFontHandle BuildRegularFontHandle(IFontAtlas atlas) =>
+        atlas.NewDelegateFontHandle(e =>
+            e.OnPreBuild(tk =>
+            {
+                // UseHellionFont swaps the source font but keeps the size
+                // selector tied to FontSizeV2 (the Hellion font ships as
+                // a single weight).
+                var basePt = Plugin.Config.UseHellionFont
+                    ? Plugin.Config.FontSizeV2
+                    : Plugin.Config.GlobalFontV2.SizePt;
+                var config = new SafeFontConfig { SizePt = basePt, GlyphRanges = Ranges };
+                // Missing embedded resource falls back to the configured
+                // system font instead of taking the whole UiBuilder down.
+                var hellionBytes = Plugin.Config.UseHellionFont ? TryGetHellionFontBytes() : null;
+                config.MergeFont = hellionBytes is not null
+                    ? tk.AddFontFromMemory(hellionBytes, config, "Hellion-Exo2")
+                    : AddFontWithFallback(tk, Plugin.Config.GlobalFontV2.FontId, config, "global");
+
+                config.SizePt = Plugin.Config.JapaneseFontV2.SizePt;
+                config.GlyphRanges = JpRange;
+                AddFontWithFallback(tk, Plugin.Config.JapaneseFontV2.FontId, config, "japanese");
+
+                config.SizePt = Plugin.Config.SymbolsFontSizeV2;
+                tk.AddGameSymbol(config);
+
+                tk.Font = config.MergeFont;
+            })
+        );
+
+    private IFontHandle BuildItalicFontHandle(IFontAtlas atlas) =>
+        atlas.NewDelegateFontHandle(e =>
+            e.OnPreBuild(tk =>
+            {
+                var config = new SafeFontConfig
+                {
+                    SizePt = Plugin.Config.ItalicFontV2.SizePt,
+                    GlyphRanges = Ranges,
+                };
+                config.MergeFont = AddFontWithFallback(
+                    tk,
+                    Plugin.Config.ItalicFontV2.FontId,
+                    config,
+                    "italic"
+                );
+
+                config.SizePt = Plugin.Config.JapaneseFontV2.SizePt;
+                config.GlyphRanges = JpRange;
+                AddFontWithFallback(tk, Plugin.Config.JapaneseFontV2.FontId, config, "japanese");
+
+                config.SizePt = Plugin.Config.SymbolsFontSizeV2;
+                tk.AddGameSymbol(config);
+
+                tk.Font = config.MergeFont;
+            })
+        );
+
+    public void Dispose()
+    {
+        Axis.Dispose();
+        AxisItalic.Dispose();
+        FontAwesome.Dispose();
+        RegularFont?.Dispose();
+        ItalicFont?.Dispose();
+    }
+
+    // Returns null when the embedded font resource is missing. Should not
     // happen on a signed release build, but a broken csproj or hand-rolled
-    // dev build can land here. Caller falls back to the system font path so
+    // dev build can land here. Caller falls back to the system font path
-    // the plugin still loads instead of crashing the whole UiBuilder.
+    // so the plugin still loads instead of crashing the whole UiBuilder.
     private static byte[]? TryGetHellionFontBytes()
     {
         if (HellionFontBytes is not null)
@@ -98,10 +237,8 @@ public class FontManager
             foreach (var c in reader.Glyphs)
                 builder.AddChar(c.Char);
 
-            // various symbols
             // French
             // Romanian
-            // builder.AddText("←→↑↓《》■※☀★★☆♥♡ヅツッシ☀☁☂℃℉°♀♂♠♣♦♣♧®©™€$£♯♭♪✓√◎◆◇♦■□〇●△▽▼▲‹›≤≥<«“”─＼～");
             builder.AddText("Œœ");
             builder.AddText("ĂăÂâÎîȘșȚț");
 
@@ -122,100 +259,6 @@ public class FontManager
         JpRange = BuildRange(GlyphRangesJapanese.GlyphRanges);
     }
 
-    // CPU-bound build offloaded to Task.Run; runs parallel with theme init
-    public async Task BuildFontsAsync(CancellationToken cancellationToken)
-    {
-        cancellationToken.ThrowIfCancellationRequested();
-        await Task.Run(BuildFonts, cancellationToken).ConfigureAwait(false);
-    }
-
-    public void BuildFonts()
-    {
-        SetUpRanges();
-
-        Axis = Plugin.Interface.UiBuilder.FontAtlas.NewGameFontHandle(
-            new GameFontStyle(GameFontFamily.Axis, SizeInPx(Plugin.Config.FontSizeV2))
-        );
-        AxisItalic = Plugin.Interface.UiBuilder.FontAtlas.NewGameFontHandle(
-            new GameFontStyle(GameFontFamily.Axis, SizeInPx(Plugin.Config.FontSizeV2))
-            {
-                SkewStrength = SizeInPx(Plugin.Config.FontSizeV2) / 6,
-            }
-        );
-
-        FontAwesome = Plugin.Interface.UiBuilder.FontAtlas.NewDelegateFontHandle(e =>
-        {
-            e.OnPreBuild(tk =>
-                tk.AddFontAwesomeIconFont(new SafeFontConfig { SizePx = GetFontSize() })
-            );
-            e.OnPostBuild(tk => tk.FitRatio(tk.Font));
-        });
-
-        RegularFont = Plugin.Interface.UiBuilder.FontAtlas.NewDelegateFontHandle(e =>
-            e.OnPreBuild(tk =>
-            {
-                // v1.2.0: UseHellionFont controls font size selection
-                var basePt = Plugin.Config.UseHellionFont
-                    ? Plugin.Config.FontSizeV2
-                    : Plugin.Config.GlobalFontV2.SizePt;
-                var config = new SafeFontConfig { SizePt = basePt, GlyphRanges = Ranges };
-                // F10.2: if the embedded font is missing, drop to the system font
-                // path rather than letting the UiBuilder throw.
-                var hellionBytes = Plugin.Config.UseHellionFont ? TryGetHellionFontBytes() : null;
-                config.MergeFont = hellionBytes is not null
-                    ? tk.AddFontFromMemory(hellionBytes, config, "Hellion-Exo2")
-                    : AddFontWithFallback(tk, Plugin.Config.GlobalFontV2.FontId, config, "global");
-
-                config.SizePt = Plugin.Config.JapaneseFontV2.SizePt;
-                config.GlyphRanges = JpRange;
-                AddFontWithFallback(tk, Plugin.Config.JapaneseFontV2.FontId, config, "japanese");
-
-                config.SizePt = Plugin.Config.SymbolsFontSizeV2;
-                tk.AddGameSymbol(config);
-
-                tk.Font = config.MergeFont;
-            })
-        );
-
-        if (Plugin.Config.ItalicEnabled)
-        {
-            ItalicFont = Plugin.Interface.UiBuilder.FontAtlas.NewDelegateFontHandle(e =>
-                e.OnPreBuild(tk =>
-                {
-                    var config = new SafeFontConfig
-                    {
-                        SizePt = Plugin.Config.ItalicFontV2.SizePt,
-                        GlyphRanges = Ranges,
-                    };
-                    config.MergeFont = AddFontWithFallback(
-                        tk,
-                        Plugin.Config.ItalicFontV2.FontId,
-                        config,
-                        "italic"
-                    );
-
-                    config.SizePt = Plugin.Config.JapaneseFontV2.SizePt;
-                    config.GlyphRanges = JpRange;
-                    AddFontWithFallback(
-                        tk,
-                        Plugin.Config.JapaneseFontV2.FontId,
-                        config,
-                        "japanese"
-                    );
-
-                    config.SizePt = Plugin.Config.SymbolsFontSizeV2;
-                    tk.AddGameSymbol(config);
-
-                    tk.Font = config.MergeFont;
-                })
-            );
-        }
-        else
-        {
-            ItalicFont = null;
-        }
-    }
-
     // Add font with fallback to NotoSansCjkRegular if unavailable
     private static ImFontPtr AddFontWithFallback(
         IFontAtlasBuildToolkitPreBuild tk,

HellionChat/Infrastructure/Hosting/InitHostedServices.cs

@@ -11,17 +11,6 @@ namespace HellionChat.Infrastructure.Hosting;
 // at Build, which runs the service ctor (IPC subscribe etc.) right then
 // instead of lazily on first GetRequiredService.
 
-internal sealed class FontManagerInitHostedService(FontManager fontManager) : IHostedService
-{
-    public Task StartAsync(CancellationToken cancellationToken)
-    {
-        fontManager.BuildFonts();
-        return Task.CompletedTask;
-    }
-
-    public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;
-}
-
 internal sealed class ThemeRegistryInitHostedService(ThemeRegistry registry) : IHostedService
 {
     public Task StartAsync(CancellationToken cancellationToken)

HellionChat/Plugin.cs

@@ -307,11 +307,13 @@ public sealed class Plugin : IAsyncDalamudPlugin
             cancellationToken.ThrowIfCancellationRequested();
 
             // Container drives service init now: Host.StartAsync triggers the
-            // IHostedService adapters (FontManager.BuildFonts, ThemeRegistry
+            // remaining IHostedService adapters (ThemeRegistry cache warmup +
-            // cache warmup + Switch, IPC eager-resolve, MessageManager
+            // Switch, IPC eager-resolve, MessageManager FilterAllTabsAsync,
-            // FilterAllTabsAsync, AutoTellTabsService.Initialize). Window
+            // AutoTellTabsService.Initialize). FontManager runs its own init
-            // registration with WindowSystem runs on the framework thread
+            // inline inside the ctor's SuppressAutoRebuild block on eager
-            // inside PluginLifecycle.LoadAsync after StartAsync returns.
+            // resolve. Window registration with WindowSystem runs on the
+            // framework thread inside PluginLifecycle.LoadAsync after
+            // StartAsync returns.
             if (_lifecycle is not null)
                 await _lifecycle.LoadAsync(cancellationToken).ConfigureAwait(false);
 
@@ -911,7 +913,10 @@ public sealed class Plugin : IAsyncDalamudPlugin
         Interface.UiBuilder.DisableUserUiHide = !Config.HideWhenUiHidden;
         ChatLogWindow.DefaultText = ImGui.GetStyle().Colors[(int)ImGuiCol.Text];
 
-        using ((Config.FontsEnabled ? FontManager.RegularFont : FontManager.Axis).Push())
+        // RegularFont is nullable only because the live rebuild path
+        // disposes it before reassigning; both ends of that swap happen on
+        // this same draw thread, so it cannot be null here.
+        using ((Config.FontsEnabled ? FontManager.RegularFont! : FontManager.Axis).Push())
             WindowSystem.Draw();
 
         ChatLogWindow.FinalizeFrame();

HellionChat/PluginHostFactory.cs

@@ -77,7 +77,9 @@ internal static class PluginHostFactory
         ));
         services.AddSingleton<FileDialogManager>(_ => new FileDialogManager());
         services.AddSingleton(sp => new Commands(sp.GetRequiredService<ILogger<Commands>>()));
-        services.AddSingleton(_ => new FontManager());
+        services.AddSingleton(sp => new FontManager(
+            sp.GetRequiredService<IDalamudPluginInterface>()
+        ));
         services.AddSingleton(_ => new StatusBar());
         services.AddSingleton(sp => new IpcManager(sp.GetRequiredService<ILogger<IpcManager>>()));
         services.AddSingleton(sp => new ExtraChat(sp.GetRequiredService<ILogger<ExtraChat>>()));
@@ -148,10 +150,9 @@ internal static class PluginHostFactory
         services.AddSingleton(sp => new FirstRunWizard(sp.GetRequiredService<Plugin>()));
 
         // Hosted-service adapters: thin wrappers around the existing init
-        // methods so the service class bodies stay unchanged.
+        // methods so the service class bodies stay unchanged. FontManager
-        services.AddHostedService(sp => new FontManagerInitHostedService(
+        // does not need one — its ctor runs the init inline inside a single
-            sp.GetRequiredService<FontManager>()
+        // SuppressAutoRebuild block on eager resolve.
-        ));
         services.AddHostedService(sp => new ThemeRegistryInitHostedService(
             sp.GetRequiredService<ThemeRegistry>()
         ));

HellionChat/Ui/Settings.cs

@@ -229,7 +229,7 @@ public sealed class SettingsWindow : Dalamud.Interface.Windowing.Window
         }
 
         if (fontChanged || fontSizeChanged || italicStateChanged)
-            Plugin.FontManager.BuildFonts();
+            Plugin.FontManager.RebuildDelegateFonts();
 
         if (languageChanged)
             Plugin.LanguageChanged(Plugin.Interface.UiLanguage);