Add barebone nuke (#5242)

Co-authored-by: Alexander Evgrashin <evgrashin.adl@gmail.com>

Content.Server/Nuke/NukeCodeSystem.cs

@@ -0,0 +1,88 @@
+using Content.Server.Chat.Managers;
+using Content.Server.Communications;
+using Content.Shared.GameTicking;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Localization;
+using Robust.Shared.Random;
+
+namespace Content.Server.Nuke
+{
+    /// <summary>
+    ///     Nuclear code is generated once per round
+    ///     One code works for all nukes
+    /// </summary>
+    public class NukeCodeSystem : EntitySystem
+    {
+        [Dependency] private readonly IRobustRandom _random = default!;
+        [Dependency] private readonly IChatManager _chat = default!;
+
+        public const int CodeLength = 6;
+        public string Code { get; private set; } = default!;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+            GenerateNewCode();
+
+            SubscribeLocalEvent<RoundRestartCleanupEvent>(OnRestart);
+        }
+
+        private void OnRestart(RoundRestartCleanupEvent ev)
+        {
+            GenerateNewCode();
+        }
+
+        /// <summary>
+        ///     Checks if code is equal to current bombs code
+        /// </summary>
+        public bool IsCodeValid(string code)
+        {
+            return code == Code;
+        }
+
+        /// <summary>
+        ///     Generate a new nuclear bomb code. Replacing old one.
+        /// </summary>
+        public void GenerateNewCode()
+        {
+            var ret = "";
+            for (int i = 0; i < CodeLength; i++)
+            {
+                var c = (char) _random.Next('0', '9' + 1);
+                ret += c;
+            }
+
+            Code = ret;
+        }
+
+        /// <summary>
+        ///     Send a nuclear code to all communication consoles
+        /// </summary>
+        /// <returns>True if at least one console received codes</returns>
+        public bool SendNukeCodes()
+        {
+            // todo: this should probably be handled by fax system
+            var wasSent = false;
+            var consoles = EntityManager.EntityQuery<CommunicationsConsoleComponent>();
+            foreach (var console in consoles)
+            {
+                if (!EntityManager.TryGetComponent(console.OwnerUid, out TransformComponent? transform))
+                    continue;
+
+                var consolePos = transform.MapPosition;
+                EntityManager.SpawnEntity("NukeCodePaper", consolePos);
+
+                wasSent = true;
+            }
+
+            if (wasSent)
+            {
+                var msg = Loc.GetString("nuke-component-announcement-send-codes");
+                _chat.DispatchStationAnnouncement(msg);
+            }
+
+            return wasSent;
+        }
+    }
+}