Power Rework (#863)

Co-authored-by: py01 <pyronetics01@gmail.com>

Content.Server/GameObjects/Components/NodeContainer/Nodes/AdjacentNode.cs

@@ -0,0 +1,25 @@
+using Content.Server.GameObjects.Components.NodeContainer.NodeGroups;
+using Robust.Shared.GameObjects.Components.Transform;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Content.Server.GameObjects.Components.NodeContainer.Nodes
+{
+    /// <summary>
+    ///     A <see cref="Node"/> that can reach other <see cref="AdjacentNode"/>s that are directly adjacent to it.
+    /// </summary>
+    [Node("AdjacentNode")]
+    public class AdjacentNode : Node
+    {
+        protected override IEnumerable<Node> GetReachableNodes()
+        {
+            return Owner.GetComponent<SnapGridComponent>()
+                .GetCardinalNeighborCells()
+                .SelectMany(sgc => sgc.GetLocal())
+                .Select(entity => entity.TryGetComponent<NodeContainerComponent>(out var container) ? container : null)
+                .Where(container => container != null)
+                .SelectMany(container => container.Nodes)
+                .Where(node => node != null && node != this);
+        }
+    }
+}