Add OnDamaged method to IOnDamageBehavior (#685)

* Add OnDamaged method to IOnDamageBehavior

* Adds Source, SourceMob to OnDamage.

Content.Server/GameObjects/Components/Damage/DamageThreshold.cs

@@ -1,5 +1,7 @@
 using System;
 using Content.Shared.GameObjects;
+using JetBrains.Annotations;
+using Robust.Shared.Interfaces.GameObjects;
 
 namespace Content.Server.GameObjects
 {
@@ -60,5 +62,38 @@ namespace Content.Server.GameObjects
             ExcessDamage = excess;
         }
     }
+
+    public class DamageEventArgs : EventArgs
+    {
+        /// <summary>
+        ///     Type of damage.
+        /// </summary>
+        public DamageType Type { get; }
+
+        /// <summary>
+        ///     Change in damage.
+        /// </summary>
+        public int Damage { get; }
+
+        /// <summary>
+        ///     The entity that damaged this one.
+        ///     Could be null.
+        /// </summary>
+        public IEntity Source { get; }
+
+        /// <summary>
+        ///     The mob entity that damaged this one.
+        ///     Could be null.
+        /// </summary>
+        public IEntity SourceMob { get; }
+
+        public DamageEventArgs(DamageType type, int damage, IEntity source, IEntity sourceMob)
+        {
+            Type = type;
+            Damage = damage;
+            Source = source;
+            SourceMob = sourceMob;
+        }
+    }
 }
 

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

@@ -5,6 +5,7 @@ using Content.Server.Interfaces;
 using Content.Server.Interfaces.GameObjects;
 using Content.Shared.GameObjects;
 using Robust.Shared.GameObjects;
+using Robust.Shared.Interfaces.GameObjects;
 using Robust.Shared.Serialization;
 using Robust.Shared.ViewVariables;
 
@@ -36,6 +37,7 @@ namespace Content.Server.GameObjects
         Dictionary<DamageType, List<DamageThreshold>> Thresholds = new Dictionary<DamageType, List<DamageThreshold>>();
 
         public event EventHandler<DamageThresholdPassedEventArgs> DamageThresholdPassed;
+        public event EventHandler<DamageEventArgs> Damaged;
 
         public override ComponentState GetComponentState()
         {
@@ -62,13 +64,14 @@ namespace Content.Server.GameObjects
             foreach (var damagebehavior in Owner.GetAllComponents<IOnDamageBehavior>())
             {
                 AddThresholdsFrom(damagebehavior);
+                Damaged += damagebehavior.OnDamaged;
             }
 
             RecalculateComponentThresholds();
         }
 
         /// <inheritdoc />
-        public void TakeDamage(DamageType damageType, int amount)
+        public void TakeDamage(DamageType damageType, int amount, IEntity source = null, IEntity sourceMob = null)
         {
             if (damageType == DamageType.Total)
             {
@@ -88,6 +91,8 @@ namespace Content.Server.GameObjects
             _currentDamage[damageType] = Math.Max(0, _currentDamage[damageType] + amount);
             UpdateForDamageType(damageType, oldValue);
 
+            Damaged?.Invoke(this, new DamageEventArgs(damageType, amount, source, sourceMob));
+
             if (Resistances.AppliesToTotal(damageType))
             {
                 oldTotalValue = _currentDamage[DamageType.Total];
@@ -97,13 +102,13 @@ namespace Content.Server.GameObjects
         }
 
         /// <inheritdoc />
-        public void TakeHealing(DamageType damageType, int amount)
+        public void TakeHealing(DamageType damageType, int amount, IEntity source = null, IEntity sourceMob = null)
         {
             if (damageType == DamageType.Total)
             {
                 throw new ArgumentException("Cannot heal for DamageType.Total");
             }
-            TakeDamage(damageType, -amount);
+            TakeDamage(damageType, -amount, source, sourceMob);
         }
 
         public void HealAllDamage()
@@ -163,6 +168,9 @@ namespace Content.Server.GameObjects
 
             List<DamageThreshold> thresholds = onDamageBehavior.GetAllDamageThresholds();
 
+            if (thresholds == null)
+                return;
+
             foreach (DamageThreshold threshold in thresholds)
             {
                 if (!Thresholds[threshold.DamageType].Contains(threshold))

Content.Server/GameObjects/Components/Mining/AsteroidRockComponent.cs

@@ -33,7 +33,7 @@ namespace Content.Server.GameObjects.Components.Mining
             var item = eventArgs.AttackWith;
             if (!item.TryGetComponent(out MeleeWeaponComponent meleeWeaponComponent)) return false;
 
-            Owner.GetComponent<DamageableComponent>().TakeDamage(DamageType.Brute, meleeWeaponComponent.Damage);
+            Owner.GetComponent<DamageableComponent>().TakeDamage(DamageType.Brute, meleeWeaponComponent.Damage, item, eventArgs.User);
 
             if (!item.TryGetComponent(out PickaxeComponent pickaxeComponent)) return true;
             if (!string.IsNullOrWhiteSpace(pickaxeComponent.MiningSound) &&

Content.Server/GameObjects/Components/Mobs/SpeciesComponent.cs

@@ -184,8 +184,8 @@ namespace Content.Server.GameObjects
                     bruteDamage += 30;
                     break;
             }
-            Owner.GetComponent<DamageableComponent>().TakeDamage(DamageType.Brute, bruteDamage);
+            Owner.GetComponent<DamageableComponent>().TakeDamage(DamageType.Brute, bruteDamage, eventArgs.Source);
-            Owner.GetComponent<DamageableComponent>().TakeDamage(DamageType.Heat, burnDamage);
+            Owner.GetComponent<DamageableComponent>().TakeDamage(DamageType.Heat, burnDamage, eventArgs.Source);
         }
     }
 

Content.Server/GameObjects/Components/Power/PoweredLightComponent.cs

@@ -73,7 +73,7 @@ namespace Content.Server.GameObjects.Components.Power
 
             void Burn()
             {
-                damageableComponent.TakeDamage(DamageType.Heat, 20);
+                damageableComponent.TakeDamage(DamageType.Heat, 20, Owner);
             }
 
             void Eject()

Content.Server/GameObjects/Components/Projectiles/ProjectileComponent.cs

@@ -71,9 +71,12 @@ namespace Content.Server.GameObjects.Components.Projectiles
             {
                 if (entity.TryGetComponent(out DamageableComponent damage))
                 {
-                    foreach (var damageType in _damages)
+                    Owner.EntityManager.TryGetEntity(Shooter, out var shooter);
+
+                    foreach (var (damageType, amount) in _damages)
                     {
-                        damage.TakeDamage(damageType.Key, damageType.Value);
+
+                        damage.TakeDamage(damageType, amount, Owner, shooter);
                     }
                 }
 

Content.Server/GameObjects/Components/Projectiles/ThrownItemComponent.cs

@@ -31,7 +31,7 @@ namespace Content.Server.GameObjects.Components
             {
                 if (entity.TryGetComponent(out DamageableComponent damage))
                 {
-                    damage.TakeDamage(DamageType.Brute, 10);
+                    damage.TakeDamage(DamageType.Brute, 10, Owner, User);
                 }
             }
 

Content.Server/GameObjects/Components/Temperature/TemperatureComponent.cs

@@ -43,7 +43,7 @@ namespace Content.Server.GameObjects
 
             _secondsSinceLastDamageUpdate += frameTime;
 
-            Owner.TryGetComponent<DamageableComponent>(out DamageableComponent component);
+            Owner.TryGetComponent(out DamageableComponent component);
 
             while (_secondsSinceLastDamageUpdate >= 1)
             {

Content.Server/GameObjects/Components/Weapon/Melee/MeleeWeaponComponent.cs

@@ -96,7 +96,7 @@ namespace Content.Server.GameObjects.Components.Weapon.Melee
 
                 if (entity.TryGetComponent(out DamageableComponent damageComponent))
                 {
-                    damageComponent.TakeDamage(DamageType.Brute, Damage);
+                    damageComponent.TakeDamage(DamageType.Brute, Damage, Owner, eventArgs.User);
                     hitEntities.Add(entity);
                 }
             }

Content.Server/GameObjects/Components/Weapon/Ranged/Hitscan/HitscanWeaponComponent.cs

@@ -92,15 +92,15 @@ namespace Content.Server.GameObjects.Components.Weapon.Ranged.Hitscan
             var ray = new CollisionRay(userPosition, angle.ToVec(), (int)(CollisionGroup.Impassable | CollisionGroup.MobImpassable));
             var rayCastResults = IoCManager.Resolve<IPhysicsManager>().IntersectRay(user.Transform.MapID, ray, MaxLength, user);
 
-            Hit(rayCastResults, energyModifier);
+            Hit(rayCastResults, energyModifier, user);
             AfterEffects(user, rayCastResults, angle, energyModifier);
         }
 
-        protected virtual void Hit(RayCastResults ray, float damageModifier)
+        protected virtual void Hit(RayCastResults ray, float damageModifier, IEntity user = null)
         {
             if (ray.HitEntity != null && ray.HitEntity.TryGetComponent(out DamageableComponent damage))
             {
-                damage.TakeDamage(DamageType.Heat, (int)Math.Round(_damage * damageModifier, MidpointRounding.AwayFromZero));
+                damage.TakeDamage(DamageType.Heat, (int)Math.Round(_damage * damageModifier, MidpointRounding.AwayFromZero), Owner, user);
                 //I used Math.Round over Convert.toInt32, as toInt32 always rounds to
                 //even numbers if halfway between two numbers, rather than rounding to nearest
             }

Content.Server/Interfaces/GameObjects/Components/Damage/IDamageableComponent.cs

@@ -17,15 +17,19 @@ namespace Content.Server.Interfaces.GameObjects
         /// </summary>
         /// <param name="damageType">Type of damage being received.</param>
         /// <param name="amount">Amount of damage being received.</param>
-        void TakeDamage(DamageType damageType, int amount);
+        /// <param name="source">Entity that damaged this entity.</param>
+        /// <param name="sourceMob">Mob that damaged this entity.</param>
+        void TakeDamage(DamageType damageType, int amount, IEntity source, IEntity sourceMob);
 
         /// <summary>
         /// Handles receiving healing.
         /// Converts healing via the resistance set then applies it
         /// and informs components of thresholds passed as necessary.
         /// </summary>
-        /// <param name="damageType">Type of damage being received.</param>
+        /// <param name="damageType">Type of healing being received.</param>
-        /// <param name="amount">Amount of damage being received.</param>
+        /// <param name="amount">Amount of healing being received.</param>
-        void TakeHealing(DamageType damageType, int amount);
+        /// <param name="source">Entity that healed this entity.</param>
+        /// <param name="sourceMob">Mob that healed this entity.</param>
+        void TakeHealing(DamageType damageType, int amount, IEntity source, IEntity sourceMob);
     }
 }

Content.Server/Interfaces/GameObjects/IOnDamageBehavior.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using Content.Server.GameObjects;
 
 namespace Content.Server.Interfaces
@@ -15,13 +16,20 @@ namespace Content.Server.Interfaces
         /// Gets a list of all DamageThresholds this component/entity are interested in.
         /// </summary>
         /// <returns>List of DamageThresholds to be added to DamageableComponent for watching.</returns>
-        List<DamageThreshold> GetAllDamageThresholds();
+        List<DamageThreshold> GetAllDamageThresholds() => null;
 
         /// <summary>
         /// Damage threshold passed event hookup.
         /// </summary>
         /// <param name="obj">Damageable component.</param>
         /// <param name="e">Damage threshold and whether it's passed in one way or another.</param>
-        void OnDamageThresholdPassed(object obj, DamageThresholdPassedEventArgs e);
+        void OnDamageThresholdPassed(object obj, DamageThresholdPassedEventArgs e) { }
+
+        /// <summary>
+        /// Called when the entity is damaged.
+        /// </summary>
+        /// <param name="obj">Damageable component.</param>
+        /// <param name="e">DamageEventArgs</param>
+        void OnDamaged(object obj, DamageEventArgs e) { }
     }
 }