Fluid spread refactor (#11908)

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>
Fix undefined

Content.Server/Fluids/EntitySystems/PuddleDebugDebugOverlaySystem.cs

@@ -0,0 +1,84 @@
+using Content.Server.Fluids.Components;
+using Content.Shared.Fluids;
+using Robust.Server.Player;
+using Robust.Shared.Map;
+using Robust.Shared.Timing;
+
+namespace Content.Server.Fluids.EntitySystems;
+
+public sealed class PuddleDebugDebugOverlaySystem : SharedPuddleDebugOverlaySystem
+{
+    [Dependency] private readonly IGameTiming _timing = default!;
+    [Dependency] private readonly IMapManager _mapManager = default!;
+
+    private readonly HashSet<IPlayerSession> _playerObservers = new();
+
+
+    public bool ToggleObserver(IPlayerSession observer)
+    {
+        NextTick ??= _timing.CurTime + Cooldown;
+
+        if (_playerObservers.Contains(observer))
+        {
+            RemoveObserver(observer);
+            return false;
+        }
+
+        _playerObservers.Add(observer);
+        return true;
+    }
+
+    private void RemoveObserver(IPlayerSession observer)
+    {
+        if (!_playerObservers.Remove(observer))
+        {
+            return;
+        }
+
+        var message = new PuddleOverlayDisableMessage();
+        RaiseNetworkEvent(message, observer.ConnectedClient);
+    }
+
+    public override void Update(float frameTime)
+    {
+        base.Update(frameTime);
+        if (NextTick == null || _timing.CurTime < NextTick)
+            return;
+
+        foreach (var session in _playerObservers)
+        {
+            if (session.AttachedEntity is not { Valid: true } entity)
+                continue;
+
+            var transform = EntityManager.GetComponent<TransformComponent>(entity);
+
+            var worldBounds = Box2.CenteredAround(transform.WorldPosition,
+                new Vector2(LocalViewRange, LocalViewRange));
+
+
+            foreach (var grid in _mapManager.FindGridsIntersecting(transform.MapID, worldBounds))
+            {
+                var data = new List<PuddleDebugOverlayData>();
+                var gridUid = grid.GridEntityId;
+
+                if (!Exists(gridUid))
+                    continue;
+
+                foreach (var uid in grid.GetAnchoredEntities(worldBounds))
+                {
+                    PuddleComponent? puddle = null;
+                    TransformComponent? xform = null;
+                    if (!Resolve(uid, ref puddle, ref xform, false))
+                        continue;
+
+                    var pos = xform.Coordinates.ToVector2i(EntityManager, _mapManager);
+                    data.Add(new PuddleDebugOverlayData(pos, puddle.CurrentVolume));
+                }
+
+                RaiseNetworkEvent(new PuddleOverlayDebugMessage(gridUid, data.ToArray()));
+            }
+        }
+
+        NextTick = _timing.CurTime + Cooldown;
+    }
+}