Clean up polymorphsystem (#14297)

Content.Server/Polymorph/Systems/PolymorphSystem.Collide.cs

@@ -0,0 +1,60 @@
+using Content.Server.Polymorph.Components;
+using Content.Shared.Projectiles;
+using Robust.Shared.Audio;
+using Robust.Shared.Physics.Events;
+
+namespace Content.Server.Polymorph.Systems;
+
+public partial class PolymorphSystem
+{
+    // Need to do this so we don't get a collection enumeration error in physics by polymorphing
+    // an entity we're colliding with
+    private Queue<PolymorphQueuedData> _queuedPolymorphUpdates = new();
+
+    public void UpdateCollide()
+    {
+        while (_queuedPolymorphUpdates.TryDequeue(out var data))
+        {
+            if (Deleted(data.Ent))
+                continue;
+
+            var ent = PolymorphEntity(data.Ent, data.Polymorph);
+            if (ent != null)
+            {
+                _audio.PlayPvs(data.Sound, ent.Value);
+            }
+        }
+    }
+
+    private void InitializeCollide()
+    {
+        SubscribeLocalEvent<PolymorphOnCollideComponent, StartCollideEvent>(OnPolymorphCollide);
+    }
+
+    private void OnPolymorphCollide(EntityUid uid, PolymorphOnCollideComponent component, ref StartCollideEvent args)
+    {
+        if (args.OurFixture.ID != SharedProjectileSystem.ProjectileFixture)
+            return;
+
+        var other = args.OtherFixture.Body.Owner;
+        if (!component.Whitelist.IsValid(other)
+            || component.Blacklist != null && component.Blacklist.IsValid(other))
+            return;
+
+        _queuedPolymorphUpdates.Enqueue(new (other, component.Sound, component.Polymorph));
+    }
+}
+
+public struct PolymorphQueuedData
+{
+    public EntityUid Ent;
+    public SoundSpecifier Sound;
+    public string Polymorph;
+
+    public PolymorphQueuedData(EntityUid ent, SoundSpecifier sound, string polymorph)
+    {
+        Ent = ent;
+        Sound = sound;
+        Polymorph = polymorph;
+    }
+}