Re-organize all projects (#4166)

Content.Server/APC/ApcNetSystem.cs

@@ -0,0 +1,45 @@
+#nullable enable
+using System.Collections.Generic;
+using Content.Shared.GameTicking;
+using JetBrains.Annotations;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Timing;
+
+namespace Content.Server.APC
+{
+    [UsedImplicitly]
+    internal sealed class ApcNetSystem : EntitySystem, IResettingEntitySystem
+    {
+        [Dependency] private readonly IPauseManager _pauseManager = default!;
+
+        private HashSet<IApcNet> _apcNets = new();
+
+        public override void Update(float frameTime)
+        {
+            foreach (var apcNet in _apcNets)
+            {
+                var gridId = apcNet.GridId;
+                if (gridId != null && !_pauseManager.IsGridPaused(gridId.Value))
+                    apcNet.Update(frameTime);
+            }
+        }
+
+        public void AddApcNet(ApcNetNodeGroup apcNet)
+        {
+            _apcNets.Add(apcNet);
+        }
+
+        public void RemoveApcNet(ApcNetNodeGroup apcNet)
+        {
+            _apcNets.Remove(apcNet);
+        }
+
+        public void Reset()
+        {
+            // NodeGroupSystem does not remake ApcNets affected during restarting until a frame later,
+            // when their grid is invalid. So, we are clearing them on round restart.
+            _apcNets.Clear();
+        }
+    }
+}