Make DoAfters use DamageChangedMessage instead of an event (#3115)

Content.Server/GameObjects/Components/DoAfterComponent.cs

@@ -2,7 +2,9 @@
 using System.Collections.Generic;
 using Content.Server.GameObjects.EntitySystems.DoAfter;
 using Content.Shared.GameObjects.Components;
+using Content.Shared.GameObjects.Components.Damage;
 using Robust.Shared.GameObjects;
+using Robust.Shared.Interfaces.GameObjects;
 
 namespace Content.Server.GameObjects.Components
 {
@@ -40,6 +42,35 @@ namespace Content.Server.GameObjects.Components
             return new DoAfterComponentState(toAdd);
         }
 
+        public override void HandleMessage(ComponentMessage message, IComponent? component)
+        {
+            base.HandleMessage(message, component);
+
+            switch (message)
+            {
+                case DamageChangedMessage msg:
+                    if (DoAfters.Count == 0)
+                    {
+                        return;
+                    }
+
+                    if (!msg.TookDamage)
+                    {
+                        return;
+                    }
+
+                    foreach (var doAfter in _doAfters.Keys)
+                    {
+                        if (doAfter.EventArgs.BreakOnDamage)
+                        {
+                            doAfter.TookDamage = true;
+                        }
+                    }
+
+                    break;
+            }
+        }
+
         public void Add(DoAfter doAfter)
         {
             _doAfters.Add(doAfter, _runningIndex);

Content.Server/GameObjects/EntitySystems/DoAfter/DoAfter.cs

@@ -4,7 +4,6 @@ using System.Threading.Tasks;
 using Content.Server.GameObjects.Components.GUI;
 using Content.Server.GameObjects.Components.Items.Storage;
 using Content.Server.GameObjects.Components.Mobs;
-using Content.Shared.GameObjects.Components.Damage;
 using Robust.Shared.Interfaces.Timing;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
@@ -27,7 +26,7 @@ namespace Content.Server.GameObjects.EntitySystems.DoAfter
 
         public EntityCoordinates TargetGrid { get; }
 
-        private bool _tookDamage;
+        public bool TookDamage { get; set; }
 
         public DoAfterStatus Status => AsTask.IsCompletedSuccessfully ? AsTask.Result : DoAfterStatus.Running;
 
@@ -63,11 +62,6 @@ namespace Content.Server.GameObjects.EntitySystems.DoAfter
             AsTask = Tcs.Task;
         }
 
-        public void HandleDamage(DamageChangedEventArgs args)
-        {
-            _tookDamage = true;
-        }
-
         public void Run(float frameTime)
         {
             switch (Status)
@@ -130,7 +124,7 @@ namespace Content.Server.GameObjects.EntitySystems.DoAfter
                 return true;
             }
 
-            if (EventArgs.BreakOnDamage && _tookDamage)
+            if (EventArgs.BreakOnDamage && TookDamage)
             {
                 return true;
             }

Content.Server/GameObjects/EntitySystems/DoAfter/DoAfterSystem.cs

@@ -4,7 +4,6 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 using Content.Server.GameObjects.Components;
-using Content.Shared.GameObjects.Components.Damage;
 using JetBrains.Annotations;
 using Robust.Shared.GameObjects.Systems;
 
@@ -68,21 +67,9 @@ namespace Content.Server.GameObjects.EntitySystems.DoAfter
             // Caller's gonna be responsible for this I guess
             var doAfterComponent = eventArgs.User.GetComponent<DoAfterComponent>();
             doAfterComponent.Add(doAfter);
-            IDamageableComponent? damageableComponent = null;
-
-            // TODO: If the component's deleted this may not get unsubscribed?
-            if (eventArgs.BreakOnDamage && eventArgs.User.TryGetComponent(out damageableComponent))
-            {
-                damageableComponent.HealthChangedEvent += doAfter.HandleDamage;
-            }
 
             await doAfter.AsTask;
 
-            if (damageableComponent != null)
-            {
-                damageableComponent.HealthChangedEvent -= doAfter.HandleDamage;
-            }
-
             return doAfter.Status;
         }
     }

Content.Shared/GameObjects/Components/Damage/DamageChangedMessage.cs

@@ -31,5 +31,21 @@ namespace Content.Shared.GameObjects.Components.Damage
         ///     List containing data on each <see cref="DamageType"/> that was changed.
         /// </summary>
         public IReadOnlyList<DamageChangeData> Data { get; }
+
+        public bool TookDamage
+        {
+            get
+            {
+                foreach (var datum in Data)
+                {
+                    if (datum.Delta > 0)
+                    {
+                        return true;
+                    }
+                }
+
+                return false;
+            }
+        }
     }
 }

Content.Shared/GameObjects/Components/Damage/DamageableComponent.cs

@@ -39,8 +39,6 @@ namespace Content.Shared.GameObjects.Components.Damage
         private readonly HashSet<DamageClass> _supportedClasses = new();
         private DamageFlag _flags;
 
-        public event Action<DamageChangedEventArgs>? HealthChangedEvent;
-
         // TODO DAMAGE Use as default values, specify overrides in a separate property through yaml for better (de)serialization
         [ViewVariables] public string DamageContainerId { get; set; } = default!;
 
@@ -460,7 +458,6 @@ namespace Content.Shared.GameObjects.Components.Damage
         protected virtual void OnHealthChanged(DamageChangedEventArgs e)
         {
             Owner.EntityManager.EventBus.RaiseEvent(EventSource.Local, e);
-            HealthChangedEvent?.Invoke(e);
 
             var message = new DamageChangedMessage(this, e.Data);
             SendMessage(message);

Content.Shared/GameObjects/Components/Damage/IDamageableComponent.cs

@@ -9,14 +9,6 @@ namespace Content.Shared.GameObjects.Components.Damage
 {
     public interface IDamageableComponent : IComponent, IExAct
     {
-        /// <summary>
-        ///     Called when the entity's <see cref="IDamageableComponent"/> values change.
-        ///     Of note is that a "deal 0 damage" call will still trigger this event
-        ///     (including both damage negated by resistance or simply inputting 0 as
-        ///     the amount of damage to deal).
-        /// </summary>
-        event Action<DamageChangedEventArgs> HealthChangedEvent;
-
         /// <summary>
         ///     Sum of all damages taken.
         /// </summary>