Pow3r: stage 1 (#4208)

Co-authored-by: 20kdc <asdd2808@gmail.com>

Pow3r/Program.SaveLoad.cs

@@ -0,0 +1,71 @@
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text.Json;
+using Content.Server.Power.Pow3r;
+using static Content.Server.Power.Pow3r.PowerState;
+
+namespace Pow3r
+{
+    internal sealed partial class Program
+    {
+        private void LoadFromDisk()
+        {
+            if (!File.Exists("data.json"))
+                return;
+
+            var dat = JsonSerializer.Deserialize<DiskDat>(File.ReadAllBytes("data.json"), SerializerOptions);
+
+            if (dat == null)
+                return;
+
+            _paused = dat.Paused;
+            _nextId = dat.NextId;
+            _currentSolver = dat.Solver;
+
+            _state = new PowerState
+            {
+                Networks = dat.Networks.ToDictionary(n => n.Id, n => n),
+                Supplies = dat.Supplies.ToDictionary(s => s.Id, s => s),
+                Loads = dat.Loads.ToDictionary(l => l.Id, l => l),
+                Batteries = dat.Batteries.ToDictionary(b => b.Id, b => b)
+            };
+
+            _displayLoads = dat.Loads.ToDictionary(n => n.Id, _ => new DisplayLoad());
+            _displaySupplies = dat.Supplies.ToDictionary(n => n.Id, _ => new DisplaySupply());
+            _displayBatteries = dat.Batteries.ToDictionary(n => n.Id, _ => new DisplayBattery());
+            _displayNetworks = dat.Networks.ToDictionary(n => n.Id, _ => new DisplayNetwork());
+
+            RefreshLinks();
+        }
+
+        private void SaveToDisk()
+        {
+            var data = new DiskDat
+            {
+                Paused = _paused,
+                NextId = _nextId,
+                Solver = _currentSolver,
+
+                Loads = _state.Loads.Values.ToList(),
+                Batteries = _state.Batteries.Values.ToList(),
+                Networks = _state.Networks.Values.ToList(),
+                Supplies = _state.Supplies.Values.ToList()
+            };
+
+            File.WriteAllBytes("data.json", JsonSerializer.SerializeToUtf8Bytes(data, SerializerOptions));
+        }
+
+        private sealed class DiskDat
+        {
+            public bool Paused;
+            public int NextId;
+            public int Solver;
+
+            public List<Load> Loads;
+            public List<Network> Networks;
+            public List<Supply> Supplies;
+            public List<Battery> Batteries;
+        }
+    }
+}