Add mob retaliation (#19901)

Content.Server/NPC/Systems/FactionExceptionSystem.cs

@@ -1,33 +0,0 @@
-using Content.Server.NPC.Components;
-
-namespace Content.Server.NPC.Systems;
-
-/// <summary>
-/// Prevents an NPC from attacking some entities from an enemy faction.
-/// </summary>
-public sealed class FactionExceptionSystem : EntitySystem
-{
-    /// <summary>
-    /// Returns whether the entity from an enemy faction won't be attacked
-    /// </summary>
-    public bool IsIgnored(FactionExceptionComponent comp, EntityUid target)
-    {
-        return comp.Ignored.Contains(target);
-    }
-
-    /// <summary>
-    /// Prevents an entity from an enemy faction from being attacked
-    /// </summary>
-    public void IgnoreEntity(FactionExceptionComponent comp, EntityUid target)
-    {
-        comp.Ignored.Add(target);
-    }
-
-    /// <summary>
-    /// Prevents a list of entities from an enemy faction from being attacked
-    /// </summary>
-    public void IgnoreEntities(FactionExceptionComponent comp, IEnumerable<EntityUid> ignored)
-    {
-        comp.Ignored.UnionWith(ignored);
-    }
-}

Content.Server/NPC/Systems/NPCRetaliationSystem.cs

@@ -0,0 +1,90 @@
+using Content.Server.NPC.Components;
+using Content.Shared.CombatMode;
+using Content.Shared.Damage;
+using Content.Shared.Mobs.Components;
+using Robust.Shared.Collections;
+using Robust.Shared.Timing;
+
+namespace Content.Server.NPC.Systems;
+
+/// <summary>
+/// Handles NPC which become aggressive after being attacked.
+/// </summary>
+public sealed class NPCRetaliationSystem : EntitySystem
+{
+    [Dependency] private readonly IGameTiming _timing = default!;
+    [Dependency] private readonly NpcFactionSystem _npcFaction = default!;
+
+    private readonly HashSet<EntityUid> _deAggroQueue = new();
+
+    /// <inheritdoc/>
+    public override void Initialize()
+    {
+        SubscribeLocalEvent<NPCRetaliationComponent, DamageChangedEvent>(OnDamageChanged);
+        SubscribeLocalEvent<NPCRetaliationComponent, DisarmedEvent>(OnDisarmed);
+    }
+
+    private void OnDamageChanged(EntityUid uid, NPCRetaliationComponent component, DamageChangedEvent args)
+    {
+        if (!args.DamageIncreased)
+            return;
+
+        if (args.Origin is not { } origin)
+            return;
+
+        TryRetaliate(uid, origin, component);
+    }
+
+    private void OnDisarmed(EntityUid uid, NPCRetaliationComponent component, DisarmedEvent args)
+    {
+        TryRetaliate(uid, args.Source, component);
+    }
+
+    public bool TryRetaliate(EntityUid uid, EntityUid target, NPCRetaliationComponent? component = null)
+    {
+        if (!Resolve(uid, ref component))
+            return false;
+
+        // don't retaliate against inanimate objects.
+        if (!HasComp<MobStateComponent>(target))
+            return false;
+
+        if (_npcFaction.IsEntityFriendly(uid, target))
+            return false;
+
+        _npcFaction.AggroEntity(uid, target);
+        if (component.AttackMemoryLength is { } memoryLength)
+        {
+            component.AttackMemories[target] = _timing.CurTime + memoryLength;
+        }
+
+        return true;
+    }
+
+    public override void Update(float frameTime)
+    {
+        base.Update(frameTime);
+
+        var query = EntityQueryEnumerator<NPCRetaliationComponent, FactionExceptionComponent, MetaDataComponent>();
+        while (query.MoveNext(out var uid, out var comp, out var factionException, out var metaData))
+        {
+            _deAggroQueue.Clear();
+
+            foreach (var ent in new ValueList<EntityUid>(comp.AttackMemories.Keys))
+            {
+                if (_timing.CurTime < comp.AttackMemories[ent])
+                    continue;
+
+                if (TerminatingOrDeleted(ent, metaData))
+                    _deAggroQueue.Add(ent);
+
+                _deAggroQueue.Add(ent);
+            }
+
+            foreach (var ent in _deAggroQueue)
+            {
+                _npcFaction.DeAggroEntity(uid, ent, factionException);
+            }
+        }
+    }
+}

Content.Server/NPC/Systems/NpcFactionSystem.Exception.cs

@@ -0,0 +1,130 @@
+using System.Linq;
+using Content.Server.NPC.Components;
+
+namespace Content.Server.NPC.Systems;
+
+/// <summary>
+/// Prevents an NPC from attacking some entities from an enemy faction.
+/// </summary>
+public sealed partial class NpcFactionSystem
+{
+    private EntityQuery<FactionExceptionComponent> _exceptionQuery;
+    private EntityQuery<FactionExceptionTrackerComponent> _trackerQuery;
+
+    public void InitializeException()
+    {
+        _exceptionQuery = GetEntityQuery<FactionExceptionComponent>();
+        _trackerQuery = GetEntityQuery<FactionExceptionTrackerComponent>();
+
+        SubscribeLocalEvent<FactionExceptionComponent, ComponentShutdown>(OnShutdown);
+        SubscribeLocalEvent<FactionExceptionTrackerComponent, ComponentShutdown>(OnTrackerShutdown);
+    }
+
+    private void OnShutdown(EntityUid uid, FactionExceptionComponent component, ComponentShutdown args)
+    {
+        foreach (var ent in component.Hostiles)
+        {
+            if (!_trackerQuery.TryGetComponent(ent, out var trackerComponent))
+                continue;
+            trackerComponent.Entities.Remove(uid);
+        }
+
+        foreach (var ent in component.Ignored)
+        {
+            if (!_trackerQuery.TryGetComponent(ent, out var trackerComponent))
+                continue;
+            trackerComponent.Entities.Remove(uid);
+        }
+    }
+
+    private void OnTrackerShutdown(EntityUid uid, FactionExceptionTrackerComponent component, ComponentShutdown args)
+    {
+        foreach (var ent in component.Entities)
+        {
+            if (!_exceptionQuery.TryGetComponent(ent, out var exceptionComponent))
+                continue;
+            exceptionComponent.Ignored.Remove(uid);
+            exceptionComponent.Hostiles.Remove(uid);
+        }
+    }
+
+    /// <summary>
+    /// Returns whether the entity from an enemy faction won't be attacked
+    /// </summary>
+    public bool IsIgnored(EntityUid uid, EntityUid target, FactionExceptionComponent? comp = null)
+    {
+        if (!Resolve(uid, ref comp, false))
+            return false;
+
+        return comp.Ignored.Contains(target);
+    }
+
+    /// <summary>
+    /// Returns the specific hostile entities for a given entity.
+    /// </summary>
+    public IEnumerable<EntityUid> GetHostiles(EntityUid uid, FactionExceptionComponent? comp = null)
+    {
+        if (!Resolve(uid, ref comp, false))
+            return Array.Empty<EntityUid>();
+
+        return comp.Hostiles;
+    }
+
+    /// <summary>
+    /// Prevents an entity from an enemy faction from being attacked
+    /// </summary>
+    public void IgnoreEntity(EntityUid uid, EntityUid target, FactionExceptionComponent? comp = null)
+    {
+        comp ??= EnsureComp<FactionExceptionComponent>(uid);
+        comp.Ignored.Add(target);
+        EnsureComp<FactionExceptionTrackerComponent>(target).Entities.Add(uid);
+    }
+
+    /// <summary>
+    /// Prevents a list of entities from an enemy faction from being attacked
+    /// </summary>
+    public void IgnoreEntities(EntityUid uid, IEnumerable<EntityUid> ignored, FactionExceptionComponent? comp = null)
+    {
+        comp ??= EnsureComp<FactionExceptionComponent>(uid);
+        foreach (var ignore in ignored)
+        {
+            IgnoreEntity(uid, ignore, comp);
+        }
+    }
+
+    /// <summary>
+    /// Makes an entity always be considered hostile.
+    /// </summary>
+    public void AggroEntity(EntityUid uid, EntityUid target, FactionExceptionComponent? comp = null)
+    {
+        comp ??= EnsureComp<FactionExceptionComponent>(uid);
+        comp.Hostiles.Add(target);
+        EnsureComp<FactionExceptionTrackerComponent>(target).Entities.Add(uid);
+    }
+
+    /// <summary>
+    /// Makes an entity no longer be considered hostile, if it was.
+    /// Doesn't apply to regular faction hostilities.
+    /// </summary>
+    public void DeAggroEntity(EntityUid uid, EntityUid target, FactionExceptionComponent? comp = null)
+    {
+        if (!Resolve(uid, ref comp, false))
+            return;
+        if (!comp.Hostiles.Remove(target) || !_trackerQuery.TryGetComponent(target, out var tracker))
+            return;
+        tracker.Entities.Remove(uid);
+    }
+
+    /// <summary>
+    /// Makes a list of entities no longer be considered hostile, if it was.
+    /// Doesn't apply to regular faction hostilities.
+    /// </summary>
+    public void AggroEntities(EntityUid uid, IEnumerable<EntityUid> entities, FactionExceptionComponent? comp = null)
+    {
+        comp ??= EnsureComp<FactionExceptionComponent>(uid);
+        foreach (var ent in entities)
+        {
+            AggroEntity(uid, ent, comp);
+        }
+    }
+}

Content.Server/NPC/Systems/NpcFactionSystem.cs

@@ -1,15 +1,15 @@
 using Content.Server.NPC.Components;
 using Robust.Shared.Prototypes;
 using System.Linq;
+using JetBrains.Annotations;
 
 namespace Content.Server.NPC.Systems;
 
 /// <summary>
 ///     Outlines faction relationships with each other.
 /// </summary>
-public sealed class NpcFactionSystem : EntitySystem
+public sealed partial class NpcFactionSystem : EntitySystem
 {
-    [Dependency] private readonly FactionExceptionSystem _factionException = default!;
     [Dependency] private readonly EntityLookupSystem _lookup = default!;
     [Dependency] private readonly IPrototypeManager _protoManager = default!;
 
@@ -26,6 +26,8 @@ public sealed class NpcFactionSystem : EntitySystem
         _sawmill = Logger.GetSawmill("faction");
         SubscribeLocalEvent<NpcFactionMemberComponent, ComponentStartup>(OnFactionStartup);
         _protoManager.PrototypesReloaded += OnProtoReload;
+
+        InitializeException();
         RefreshFactions();
     }
 
@@ -134,12 +136,15 @@ public sealed class NpcFactionSystem : EntitySystem
         if (TryComp<FactionExceptionComponent>(entity, out var factionException))
         {
             // ignore anything from enemy faction that we are explicitly friendly towards
-            return hostiles.Where(target => !_factionException.IsIgnored(factionException, target));
+            return hostiles
+                .Union(GetHostiles(entity, factionException))
+                .Where(target => !IsIgnored(entity, target, factionException));
         }
 
         return hostiles;
     }
 
+    [PublicAPI]
     public IEnumerable<EntityUid> GetNearbyFriendlies(EntityUid entity, float range, NpcFactionMemberComponent? component = null)
     {
         if (!Resolve(entity, ref component, false))