Use abstract class instead of interface

Dalamud/Game/AddonEventManager/AddonEventManager.cs

@@ -160,7 +160,7 @@ internal unsafe class AddonEventManager : IDisposable, IServiceType
     /// </summary>
     /// <param name="eventType">Event type that triggered this call.</param>
     /// <param name="addonInfo">Addon that triggered this call.</param>
-    private void OnAddonFinalize(AddonEvent eventType, IAddonArgs addonInfo)
+    private void OnAddonFinalize(AddonEvent eventType, AddonArgs addonInfo)
     {
         // It shouldn't be possible for this event to be anything other than PreFinalize.
         if (eventType != AddonEvent.PreFinalize) return;

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonArgs.cs

@@ -0,0 +1,46 @@
+using Dalamud.Memory;
+using FFXIVClientStructs.FFXIV.Component.GUI;
+
+namespace Dalamud.Game.Addon;
+
+/// <summary>
+/// Base class for AddonLifecycle AddonArgTypes.
+/// </summary>
+public abstract unsafe class AddonArgs
+{
+    /// <summary>
+    /// Constant string representing the name of an addon that is invalid.
+    /// </summary>
+    public const string InvalidAddon = "NullAddon";
+    
+    private string? addonName;
+
+    /// <summary>
+    /// Gets the name of the addon this args referrers to.
+    /// </summary>
+    public string AddonName => this.GetAddonName();
+    
+    /// <summary>
+    /// Gets the pointer to the addons AtkUnitBase.
+    /// </summary>
+    public nint Addon { get; init; }
+    
+    /// <summary>
+    /// Gets the type of these args.
+    /// </summary>
+    public abstract AddonArgsType Type { get; }
+
+    /// <summary>
+    /// Helper method for ensuring the name of the addon is valid.
+    /// </summary>
+    /// <returns>The name of the addon for this object. <see cref="InvalidAddon"/> when invalid.</returns>
+    private string GetAddonName()
+    {
+        if (this.Addon == nint.Zero) return InvalidAddon;
+
+        var addonPointer = (AtkUnitBase*)this.Addon;
+        if (addonPointer->Name is null) return InvalidAddon;
+
+        return this.addonName ??= MemoryHelper.ReadString((nint)addonPointer->Name, 0x20);
+    }
+}

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonDrawArgs.cs

@@ -1,13 +1,10 @@
-namespace Dalamud.Game.Addon.AddonArgTypes;
+namespace Dalamud.Game.Addon;
 
 /// <summary>
 /// Addon argument data for Finalize events.
 /// </summary>
-public class AddonDrawArgs : IAddonArgs
+public class AddonDrawArgs : AddonArgs
 {
     /// <inheritdoc/>
-    public nint Addon { get; init; }
+    public override AddonArgsType Type => AddonArgsType.Draw;
-
-    /// <inheritdoc/>
-    public AddonArgsType Type => AddonArgsType.Draw;
 }

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonFinalizeArgs.cs

@@ -1,13 +1,10 @@
-namespace Dalamud.Game.Addon.AddonArgTypes;
+namespace Dalamud.Game.Addon;
 
 /// <summary>
 /// Addon argument data for Finalize events.
 /// </summary>
-public class AddonFinalizeArgs : IAddonArgs
+public class AddonFinalizeArgs : AddonArgs
 {
     /// <inheritdoc/>
-    public nint Addon { get; init; }
+    public override AddonArgsType Type => AddonArgsType.Finalize;
-
-    /// <inheritdoc/>
-    public AddonArgsType Type => AddonArgsType.Finalize;
 }

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonRefreshArgs.cs

@@ -1,15 +1,15 @@
-namespace Dalamud.Game.Addon.AddonArgTypes;
+using System;
+using FFXIVClientStructs.FFXIV.Component.GUI;
+
+namespace Dalamud.Game.Addon;
 
 /// <summary>
 /// Addon argument data for Finalize events.
 /// </summary>
-public class AddonRefreshArgs : IAddonArgs
+public class AddonRefreshArgs : AddonArgs
 {
     /// <inheritdoc/>
-    public nint Addon { get; init; }
+    public override AddonArgsType Type => AddonArgsType.Refresh;
-
-    /// <inheritdoc/>
-    public AddonArgsType Type => AddonArgsType.Refresh;
     
     /// <summary>
     /// Gets the number of AtkValues.
@@ -20,4 +20,9 @@ public class AddonRefreshArgs : IAddonArgs
     /// Gets the address of the AtkValue array.
     /// </summary>
     public nint AtkValues { get; init; }
+        
+    /// <summary>
+    /// Gets the AtkValues in the form of a span.
+    /// </summary>
+    public unsafe Span<AtkValue> AtkValueSpan => new(this.AtkValues.ToPointer(), (int)this.AtkValueCount);
 }

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonRequestedUpdateArgs.cs

@@ -1,15 +1,12 @@
-namespace Dalamud.Game.Addon.AddonArgTypes;
+namespace Dalamud.Game.Addon;
 
 /// <summary>
 /// Addon argument data for Finalize events.
 /// </summary>
-public class AddonRequestedUpdateArgs : IAddonArgs
+public class AddonRequestedUpdateArgs : AddonArgs
 {
     /// <inheritdoc/>
-    public nint Addon { get; init; }
+    public override AddonArgsType Type => AddonArgsType.RequestedUpdate;
-
-    /// <inheritdoc/>
-    public AddonArgsType Type => AddonArgsType.RequestedUpdate;
     
     /// <summary>
     /// Gets the NumberArrayData** for this event.

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonSetupArgs.cs

@@ -1,15 +1,16 @@
-namespace Dalamud.Game.Addon.AddonArgTypes;
+using System;
+
+using FFXIVClientStructs.FFXIV.Component.GUI;
+
+namespace Dalamud.Game.Addon;
 
 /// <summary>
 /// Addon argument data for Setup events.
 /// </summary>
-public class AddonSetupArgs : IAddonArgs
+public class AddonSetupArgs : AddonArgs
 {
     /// <inheritdoc/>
-    public nint Addon { get; init; }
+    public override AddonArgsType Type => AddonArgsType.Setup;
-
-    /// <inheritdoc/>
-    public AddonArgsType Type => AddonArgsType.Setup;
     
     /// <summary>
     /// Gets the number of AtkValues.
@@ -20,4 +21,9 @@ public class AddonSetupArgs : IAddonArgs
     /// Gets the address of the AtkValue array.
     /// </summary>
     public nint AtkValues { get; init; }
+    
+    /// <summary>
+    /// Gets the AtkValues in the form of a span.
+    /// </summary>
+    public unsafe Span<AtkValue> AtkValueSpan => new(this.AtkValues.ToPointer(), (int)this.AtkValueCount);
 }

Dalamud/Game/AddonLifecycle/AddonArgTypes/AddonUpdateArgs.cs

@@ -1,15 +1,12 @@
-namespace Dalamud.Game.Addon.AddonArgTypes;
+namespace Dalamud.Game.Addon;
 
 /// <summary>
 /// Addon argument data for Finalize events.
 /// </summary>
-public class AddonUpdateArgs : IAddonArgs
+public class AddonUpdateArgs : AddonArgs
 {
     /// <inheritdoc/>
-    public nint Addon { get; init; }
+    public override AddonArgsType Type => AddonArgsType.Update;
-
-    /// <inheritdoc/>
-    public AddonArgsType Type => AddonArgsType.Update;
     
     /// <summary>
     /// Gets the time since the last update.

Dalamud/Game/AddonLifecycle/AddonArgsType.cs

@@ -1,7 +1,7 @@
 namespace Dalamud.Game.Addon;
 
 /// <summary>
-/// Enumeration for available AddonLifecycle arg data
+/// Enumeration for available AddonLifecycle arg data.
 /// </summary>
 public enum AddonArgsType
 {

Dalamud/Game/AddonLifecycle/AddonLifecycle.cs

@@ -3,7 +3,6 @@ using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Linq;
 
-using Dalamud.Game.Addon.AddonArgTypes;
 using Dalamud.Hooking;
 using Dalamud.Hooking.Internal;
 using Dalamud.IoC;
@@ -128,7 +127,7 @@ internal unsafe class AddonLifecycle : IDisposable, IServiceType
         this.onAddonRequestedUpdateHook.Enable();
     }
 
-    private void InvokeListeners(AddonEvent eventType, IAddonArgs args)
+    private void InvokeListeners(AddonEvent eventType, AddonArgs args)
     {
         // Match on string.empty for listeners that want events for all addons.
         foreach (var listener in this.eventListeners.Where(listener => listener.EventType == eventType && (listener.AddonName == args.AddonName || listener.AddonName == string.Empty)))
@@ -141,7 +140,7 @@ internal unsafe class AddonLifecycle : IDisposable, IServiceType
     {
         try
         {
-            this.InvokeListeners(AddonEvent.PreSetup, new AddonSetupArgs()
+            this.InvokeListeners(AddonEvent.PreSetup, new AddonSetupArgs
             {
                 Addon = (nint)addon, 
                 AtkValueCount = valueCount,
@@ -157,7 +156,7 @@ internal unsafe class AddonLifecycle : IDisposable, IServiceType
 
         try
         {
-            this.InvokeListeners(AddonEvent.PostSetup, new AddonSetupArgs()
+            this.InvokeListeners(AddonEvent.PostSetup, new AddonSetupArgs
             {
                 Addon = (nint)addon, 
                 AtkValueCount = valueCount,

Dalamud/Game/AddonLifecycle/IAddonArgs.cs

@@ -1,25 +0,0 @@
-using Dalamud.Memory;
-using FFXIVClientStructs.FFXIV.Component.GUI;
-
-namespace Dalamud.Game.Addon;
-
-/// <summary>
-/// Interface representing the argument data for AddonLifecycle events.
-/// </summary>
-public unsafe interface IAddonArgs
-{
-    /// <summary>
-    /// Gets the name of the addon this args referrers to.
-    /// </summary>
-    string AddonName => this.Addon == nint.Zero ? "NullAddon" : MemoryHelper.ReadString((nint)((AtkUnitBase*)this.Addon)->Name, 0x20);
-    
-    /// <summary>
-    /// Gets the pointer to the addons AtkUnitBase.
-    /// </summary>
-    nint Addon { get; init; }
-    
-    /// <summary>
-    /// Gets the type of these args.
-    /// </summary>
-    AddonArgsType Type { get; }
-}

Dalamud/Game/Gui/Dtr/DtrBar.cs

@@ -255,7 +255,7 @@ public sealed unsafe class DtrBar : IDisposable, IServiceType, IDtrBar
         }
     }
     
-    private void OnDtrPostDraw(AddonEvent eventType, IAddonArgs addonInfo)
+    private void OnDtrPostDraw(AddonEvent eventType, AddonArgs addonInfo)
     {
         var addon = (AtkUnitBase*)addonInfo.Addon;
 
@@ -300,7 +300,7 @@ public sealed unsafe class DtrBar : IDisposable, IServiceType, IDtrBar
         }
     }
 
-    private void OnAddonRequestedUpdateDetour(AddonEvent eventType, IAddonArgs addonInfo)
+    private void OnAddonRequestedUpdateDetour(AddonEvent eventType, AddonArgs addonInfo)
     {
         var addon = (AtkUnitBase*)addonInfo.Addon;
         

Dalamud/Interface/Internal/Windows/SelfTest/AgingSteps/AddonLifecycleAgingStep.cs

@@ -100,32 +100,32 @@ internal class AddonLifecycleAgingStep : IAgingStep
         }
     }
     
-    private void PostSetup(AddonEvent eventType, IAddonArgs addonInfo)
+    private void PostSetup(AddonEvent eventType, AddonArgs addonInfo)
     {        
         if (this.currentStep is TestStep.CharacterSetup) this.currentStep++;
     }
     
-    private void PostUpdate(AddonEvent eventType, IAddonArgs addonInfo)
+    private void PostUpdate(AddonEvent eventType, AddonArgs addonInfo)
     {
         if (this.currentStep is TestStep.CharacterUpdate) this.currentStep++;
     }
     
-    private void PostDraw(AddonEvent eventType, IAddonArgs addonInfo)
+    private void PostDraw(AddonEvent eventType, AddonArgs addonInfo)
     {
         if (this.currentStep is TestStep.CharacterDraw) this.currentStep++;
     }
     
-    private void PostRefresh(AddonEvent eventType, IAddonArgs addonInfo)
+    private void PostRefresh(AddonEvent eventType, AddonArgs addonInfo)
     {
         if (this.currentStep is TestStep.CharacterRefresh) this.currentStep++;
     }
     
-    private void PostRequestedUpdate(AddonEvent eventType, IAddonArgs addonInfo)
+    private void PostRequestedUpdate(AddonEvent eventType, AddonArgs addonInfo)
     {
         if (this.currentStep is TestStep.CharacterRequestedUpdate) this.currentStep++;
     }
     
-    private void PreFinalize(AddonEvent eventType, IAddonArgs addonInfo)
+    private void PreFinalize(AddonEvent eventType, AddonArgs addonInfo)
     {
         if (this.currentStep is TestStep.CharacterFinalize) this.currentStep++;
     }

Dalamud/Plugin/Services/IAddonLifecycle.cs

@@ -15,7 +15,7 @@ public interface IAddonLifecycle
     /// </summary>
     /// <param name="eventType">The event type that triggered the message.</param>
     /// <param name="args">Information about what addon triggered the message.</param>
-    public delegate void AddonEventDelegate(AddonEvent eventType, IAddonArgs args);
+    public delegate void AddonEventDelegate(AddonEvent eventType, AddonArgs args);
     
     /// <summary>
     /// Register a listener that will trigger on the specified event and any of the specified addons.