Config change event (#1301)

* Add events for config changes

* Update ConfigChangeEvent.cs

* change event names

---------

Co-authored-by: goat <16760685+goaaats@users.noreply.github.com>

Dalamud/Game/Config/ConfigChangeEvent.cs

@@ -0,0 +1,7 @@
+using System;
+
+namespace Dalamud.Game.Config;
+
+public abstract record ConfigChangeEvent(Enum Option);
+
+public record ConfigChangeEvent<T>(T ConfigOption) : ConfigChangeEvent(ConfigOption) where T : Enum;

Dalamud/Game/Config/GameConfig.cs

@@ -1,6 +1,10 @@
-using Dalamud.IoC;
+using System;
+using Dalamud.Hooking;
+using Dalamud.IoC;
 using Dalamud.IoC.Internal;
 using Dalamud.Plugin.Services;
+using Dalamud.Utility;
+using FFXIVClientStructs.FFXIV.Common.Configuration;
 using Serilog;
 
 namespace Dalamud.Game.Config;
@@ -14,10 +18,13 @@ namespace Dalamud.Game.Config;
 #pragma warning disable SA1015
 [ResolveVia<IGameConfig>]
 #pragma warning restore SA1015
-public sealed class GameConfig : IServiceType, IGameConfig
+public sealed class GameConfig : IServiceType, IGameConfig, IDisposable
 {
+    private readonly GameConfigAddressResolver address = new();
+    private Hook<ConfigChangeDelegate>? configChangeHook;
+
     [ServiceManager.ServiceConstructor]
-    private unsafe GameConfig(Framework framework)
+    private unsafe GameConfig(Framework framework, SigScanner sigScanner)
     {
         framework.RunOnTick(() =>
         {
@@ -27,9 +34,18 @@ public sealed class GameConfig : IServiceType, IGameConfig
             this.System = new GameConfigSection("System", framework, &commonConfig->ConfigBase);
             this.UiConfig = new GameConfigSection("UiConfig", framework, &commonConfig->UiConfig);
             this.UiControl = new GameConfigSection("UiControl", framework, () => this.UiConfig.TryGetBool("PadMode", out var padMode) && padMode ? &commonConfig->UiControlGamepadConfig : &commonConfig->UiControlConfig);
+        
+            this.address.Setup(sigScanner);
+            this.configChangeHook = Hook<ConfigChangeDelegate>.FromAddress(this.address.ConfigChangeAddress, this.OnConfigChanged);
+            this.configChangeHook?.Enable();
         });
     }
 
+    private unsafe delegate nint ConfigChangeDelegate(ConfigBase* configBase, ConfigEntry* configEntry);
+    
+    /// <inheritdoc/>
+    public event EventHandler<ConfigChangeEvent> Changed;
+    
     /// <inheritdoc/>
     public GameConfigSection System { get; private set; }
 
@@ -110,4 +126,43 @@ public sealed class GameConfig : IServiceType, IGameConfig
     
     /// <inheritdoc/>
     public void Set(UiControlOption option, string value) => this.UiControl.Set(option.GetName(), value);
+    
+    /// <inheritdoc/>
+    void IDisposable.Dispose()
+    {
+        this.configChangeHook?.Disable();
+        this.configChangeHook?.Dispose();
+    }
+    
+    private unsafe nint OnConfigChanged(ConfigBase* configBase, ConfigEntry* configEntry)
+    {
+        var returnValue = this.configChangeHook!.Original(configBase, configEntry);
+        try
+        {
+            ConfigChangeEvent? eventArgs = null;
+            
+            if (configBase == this.System.GetConfigBase())
+            {
+                eventArgs = this.System.InvokeChange<SystemConfigOption>(configEntry);
+            }
+            else if (configBase == this.UiConfig.GetConfigBase())
+            {
+                eventArgs = this.UiConfig.InvokeChange<UiConfigOption>(configEntry);
+            }
+            else if (configBase == this.UiControl.GetConfigBase())
+            {
+                eventArgs = this.UiControl.InvokeChange<UiControlOption>(configEntry);
+            }
+
+            if (eventArgs == null) return returnValue;
+
+            this.Changed?.InvokeSafely(this, eventArgs);
+        }
+        catch (Exception ex)
+        {
+            Log.Error(ex, $"Exception thrown handing {nameof(this.OnConfigChanged)} events.");
+        }
+        
+        return returnValue;
+    }
 }

Dalamud/Game/Config/GameConfigAddressResolver.cs

@@ -0,0 +1,18 @@
+namespace Dalamud.Game.Config;
+
+/// <summary>
+/// Game config system address resolver.
+/// </summary>
+public sealed class GameConfigAddressResolver : BaseAddressResolver
+{
+    /// <summary>
+    /// Gets the address of the method called when any config option is changed.
+    /// </summary>
+    public nint ConfigChangeAddress { get; private set; }
+    
+    /// <inheritdoc/>
+    protected override void Setup64Bit(SigScanner scanner)
+    {
+        this.ConfigChangeAddress = scanner.ScanText("E8 ?? ?? ?? ?? 48 8B 3F 49 3B 3E");
+    }
+}

Dalamud/Game/Config/GameConfigSection.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 
 using Dalamud.Memory;
+using Dalamud.Utility;
 using FFXIVClientStructs.FFXIV.Common.Configuration;
 using Serilog;
 
@@ -16,6 +17,12 @@ public class GameConfigSection
     private readonly Framework framework;
     private readonly Dictionary<string, uint> indexMap = new();
     private readonly Dictionary<uint, string> nameMap = new();
+    private readonly Dictionary<uint, object> enumMap = new();
+
+    /// <summary>
+    /// Event which is fired when a game config option is changed within the section.
+    /// </summary>
+    public event EventHandler<ConfigChangeEvent> Changed; 
 
     /// <summary>
     /// Initializes a new instance of the <see cref="GameConfigSection"/> class.
@@ -59,7 +66,10 @@ public class GameConfigSection
     /// </summary>
     public string SectionName { get; }
 
-    private GetConfigBaseDelegate GetConfigBase { get; }
+    /// <summary>
+    /// Gets the pointer to the config section container.
+    /// </summary>
+    internal GetConfigBaseDelegate GetConfigBase { get; }
 
     /// <summary>
     /// Attempts to get a boolean config option.
@@ -380,6 +390,35 @@ public class GameConfigSection
         });
     }
 
+    /// <summary>
+    /// Invokes a change event within the config section.
+    /// </summary>
+    /// <param name="entry">The config entry that was changed.</param>
+    /// <typeparam name="TEnum">SystemConfigOption, UiConfigOption, or UiControlOption.</typeparam>
+    /// <returns>The ConfigChangeEvent record.</returns>
+    internal unsafe ConfigChangeEvent? InvokeChange<TEnum>(ConfigEntry* entry) where TEnum : Enum
+    {
+        if (!this.enumMap.TryGetValue(entry->Index, out var enumObject))
+        {
+            if (entry->Name == null) return null;
+            var name = MemoryHelper.ReadStringNullTerminated(new IntPtr(entry->Name));
+            if (Enum.TryParse(typeof(TEnum), name, out enumObject))
+            {
+                this.enumMap.Add(entry->Index, enumObject);
+            }
+            else
+            {
+                enumObject = null;
+                this.enumMap.Add(entry->Index, null);
+            }
+        }
+
+        if (enumObject == null) return null;
+        var eventArgs = new ConfigChangeEvent<TEnum>((TEnum)enumObject);
+        this.Changed?.InvokeSafely(this, eventArgs);
+        return eventArgs;
+    }
+    
     private unsafe bool TryGetIndex(string name, out uint index)
     {
         if (this.indexMap.TryGetValue(name, out index))

Dalamud/Plugin/Services/IGameConfig.cs

@@ -1,6 +1,8 @@
-using System.Diagnostics;
+using System;
+using System.Diagnostics;
 
 using Dalamud.Game.Config;
+using FFXIVClientStructs.FFXIV.Common.Configuration;
 
 namespace Dalamud.Plugin.Services;
 
@@ -9,6 +11,11 @@ namespace Dalamud.Plugin.Services;
 /// </summary>
 public interface IGameConfig
 {
+    /// <summary>
+    /// Event which is fired when a game config option is changed.
+    /// </summary>
+    public event EventHandler<ConfigChangeEvent> Changed;
+
     /// <summary>
     /// Gets the collection of config options that persist between characters.
     /// </summary>