Polymorphs and Transformation (#8185)

Content.Server/Polymorph/Systems/PolymorphedEntitySystem.cs

@@ -0,0 +1,102 @@
+using Content.Server.Actions;
+using Content.Server.Mind.Components;
+using Content.Server.Polymorph.Components;
+using Content.Server.Popups;
+using Content.Shared.Actions;
+using Content.Shared.Actions.ActionTypes;
+using Content.Shared.Damage;
+using Content.Shared.MobState.Components;
+using Robust.Shared.Player;
+
+namespace Content.Server.Polymorph.Systems
+{
+    public sealed class PolymorphedEntitySystem : EntitySystem
+    {
+        [Dependency] private readonly ActionsSystem _actions = default!;
+        [Dependency] private readonly DamageableSystem _damageable = default!;
+        [Dependency] private readonly PopupSystem _popup = default!;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<PolymorphedEntityComponent, PolymorphComponentSetupEvent>(OnInit);
+            SubscribeLocalEvent<PolymorphedEntityComponent, RevertPolymorphActionEvent>(OnRevertPolymorphActionEvent);
+        }
+
+        private void OnRevertPolymorphActionEvent(EntityUid uid, PolymorphedEntityComponent component, RevertPolymorphActionEvent args)
+        {
+            Revert(uid);
+        }
+
+        /// <summary>
+        /// Reverts a polymorphed entity back into its original form
+        /// </summary>
+        /// <param name="uid">The entityuid of the entity being reverted</param>
+        public void Revert(EntityUid uid)
+        {
+            if (!TryComp<PolymorphedEntityComponent>(uid, out var component))
+                return;
+
+            var uidXform = Transform(uid);
+            var parentXform = Transform(component.Parent);
+
+            parentXform.AttachParent(uidXform.ParentUid);
+            parentXform.Coordinates = uidXform.Coordinates;
+
+            if (TryComp<DamageableComponent>(component.Parent, out var damageParent) &&
+                _damageable.GetScaledDamage(uid, component.Parent, out var damage) &&
+                damage != null)
+            {
+                _damageable.SetDamage(damageParent, damage);
+            }
+
+            if (TryComp<MindComponent>(uid, out var mind) && mind.Mind != null)
+            {
+                mind.Mind.TransferTo(component.Parent);
+            }
+
+            _popup.PopupEntity(Loc.GetString("polymorph-revert-popup-generic", ("parent", uid), ("child", component.Parent)), component.Parent, Filter.Pvs(component.Parent));
+            QueueDel(uid);
+        }
+
+        private void OnInit(EntityUid uid, PolymorphedEntityComponent component, PolymorphComponentSetupEvent args)
+        {
+            if (component.Prototype.Forced)
+                return;
+
+            var act = new InstantAction()
+            {
+                Event = new RevertPolymorphActionEvent(),
+                EntityIcon = component.Parent,
+                Name = Loc.GetString("polymorph-revert-action-name"),
+                Description = Loc.GetString("polymorph-revert-action-description"),
+                UseDelay = TimeSpan.FromSeconds(component.Prototype.Delay),
+           };
+    
+            _actions.AddAction(uid, act, null);
+        }
+
+        public override void Update(float frameTime)
+        {
+            base.Update(frameTime);
+
+            foreach (var entity in EntityQuery<PolymorphedEntityComponent>())
+            {
+                entity.Time += frameTime;
+
+                if(entity.Prototype.Duration != null && entity.Time >= entity.Prototype.Duration)
+                    Revert(entity.Owner);
+
+                if (!TryComp<MobStateComponent>(entity.Owner, out var mob))
+                    continue;
+
+                if ((entity.Prototype.RevertOnDeath && mob.IsDead()) ||
+                    (entity.Prototype.RevertOnCrit && mob.IsCritical()))
+                    Revert(entity.Owner);
+            }
+        }
+    }
+
+    public sealed class RevertPolymorphActionEvent : InstantActionEvent { };
+}