Make research clients grid-local (#36821)

* Limit RD servers to the station grid

* the sluth

Content.Server/Research/Systems/ResearchSystem.Client.cs

@@ -1,4 +1,5 @@
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 using Content.Server.Power.EntitySystems;
 using Content.Shared.Research.Components;
 
@@ -12,6 +13,7 @@ public sealed partial class ResearchSystem
         SubscribeLocalEvent<ResearchClientComponent, ComponentShutdown>(OnClientShutdown);
         SubscribeLocalEvent<ResearchClientComponent, BoundUIOpenedEvent>(OnClientUIOpen);
         SubscribeLocalEvent<ResearchClientComponent, ConsoleServerSelectionMessage>(OnConsoleSelect);
+        SubscribeLocalEvent<ResearchClientComponent, AnchorStateChangedEvent>(OnClientAnchorStateChanged);
 
         SubscribeLocalEvent<ResearchClientComponent, ResearchClientSyncMessage>(OnClientSyncMessage);
         SubscribeLocalEvent<ResearchClientComponent, ResearchClientServerSelectedMessage>(OnClientSelected);
@@ -23,7 +25,11 @@ public sealed partial class ResearchSystem
 
     private void OnClientSelected(EntityUid uid, ResearchClientComponent component, ResearchClientServerSelectedMessage args)
     {
-        if (!TryGetServerById(args.ServerId, out var serveruid, out var serverComponent))
+        if (!TryGetServerById(uid, args.ServerId, out var serveruid, out var serverComponent))
+            return;
+
+        // Validate that we can access this server.
+        if (!GetServers(uid).Contains((serveruid.Value, serverComponent)))
             return;
 
         UnregisterClient(uid, component);
@@ -56,12 +62,7 @@ public sealed partial class ResearchSystem
 
     private void OnClientMapInit(EntityUid uid, ResearchClientComponent component, MapInitEvent args)
     {
-        var allServers = new List<Entity<ResearchServerComponent>>();
+        var allServers = GetServers(uid).ToList();
-        var query = AllEntityQuery<ResearchServerComponent>();
-        while (query.MoveNext(out var serverUid, out var serverComp))
-        {
-            allServers.Add((serverUid, serverComp));
-        }
 
         if (allServers.Count > 0)
             RegisterClient(uid, allServers[0], component, allServers[0]);
@@ -77,6 +78,24 @@ public sealed partial class ResearchSystem
         UpdateClientInterface(uid, component);
     }
 
+    private void OnClientAnchorStateChanged(Entity<ResearchClientComponent> ent, ref AnchorStateChangedEvent args)
+    {
+        if (args.Anchored)
+        {
+            if (ent.Comp.Server is not null)
+                return;
+
+            var allServers = GetServers(ent).ToList();
+
+            if (allServers.Count > 0)
+                RegisterClient(ent, allServers[0], ent, allServers[0]);
+        }
+        else
+        {
+            UnregisterClient(ent, ent.Comp);
+        }
+    }
+
     private void UpdateClientInterface(EntityUid uid, ResearchClientComponent? component = null)
     {
         if (!Resolve(uid, ref component, false))
@@ -84,9 +103,12 @@ public sealed partial class ResearchSystem
 
         TryGetClientServer(uid, out _, out var serverComponent, component);
 
-        var names = GetServerNames();
+        var names = GetServerNames(uid);
-        var state = new ResearchClientBoundInterfaceState(names.Length, names,
+        var state = new ResearchClientBoundInterfaceState(
-            GetServerIds(), serverComponent?.Id ?? -1);
+            names.Length,
+            names,
+            GetServerIds(uid),
+            serverComponent?.Id ?? -1);
 
         _uiSystem.SetUiState(uid, ResearchClientUiKey.Key, state);
     }

Content.Server/Research/Systems/ResearchSystem.cs

@@ -18,10 +18,13 @@ namespace Content.Server.Research.Systems
         [Dependency] private readonly IAdminLogManager _adminLog = default!;
         [Dependency] private readonly IGameTiming _timing = default!;
         [Dependency] private readonly AccessReaderSystem _accessReader = default!;
+        [Dependency] private readonly EntityLookupSystem _lookup = default!;
         [Dependency] private readonly UserInterfaceSystem _uiSystem = default!;
         [Dependency] private readonly SharedPopupSystem _popup = default!;
         [Dependency] private readonly RadioSystem _radio = default!;
 
+        private static readonly HashSet<Entity<ResearchServerComponent>> ClientLookup = new();
+
         public override void Initialize()
         {
             base.Initialize();
@@ -34,19 +37,20 @@ namespace Content.Server.Research.Systems
         }
 
         /// <summary>
-        /// Gets a server based on it's unique numeric id.
+        /// Gets a server based on its unique numeric id.
         /// </summary>
+        /// <param name="client"></param>
         /// <param name="id"></param>
         /// <param name="serverUid"></param>
         /// <param name="serverComponent"></param>
         /// <returns></returns>
-        public bool TryGetServerById(int id, [NotNullWhen(true)] out EntityUid? serverUid, [NotNullWhen(true)] out ResearchServerComponent? serverComponent)
+        public bool TryGetServerById(EntityUid client, int id, [NotNullWhen(true)] out EntityUid? serverUid, [NotNullWhen(true)] out ResearchServerComponent? serverComponent)
         {
             serverUid = null;
             serverComponent = null;
 
-            var query = EntityQueryEnumerator<ResearchServerComponent>();
+            var query = GetServers(client).ToList();
-            while (query.MoveNext(out var uid, out var server))
+            foreach (var (uid, server) in query)
             {
                 if (server.Id != id)
                     continue;
@@ -61,14 +65,14 @@ namespace Content.Server.Research.Systems
         /// Gets the names of all the servers.
         /// </summary>
         /// <returns></returns>
-        public string[] GetServerNames()
+        public string[] GetServerNames(EntityUid client)
         {
-            var allServers = EntityQuery<ResearchServerComponent>(true).ToArray();
+            var allServers = GetServers(client).ToArray();
             var list = new string[allServers.Length];
 
             for (var i = 0; i < allServers.Length; i++)
             {
-                list[i] = allServers[i].ServerName;
+                list[i] = allServers[i].Comp.ServerName;
             }
 
             return list;
@@ -78,19 +82,31 @@ namespace Content.Server.Research.Systems
         /// Gets the ids of all the servers
         /// </summary>
         /// <returns></returns>
-        public int[] GetServerIds()
+        public int[] GetServerIds(EntityUid client)
         {
-            var allServers = EntityQuery<ResearchServerComponent>(true).ToArray();
+            var allServers = GetServers(client).ToArray();
             var list = new int[allServers.Length];
 
             for (var i = 0; i < allServers.Length; i++)
             {
-                list[i] = allServers[i].Id;
+                list[i] = allServers[i].Comp.Id;
             }
 
             return list;
         }
 
+        public HashSet<Entity<ResearchServerComponent>> GetServers(EntityUid client)
+        {
+            ClientLookup.Clear();
+
+            var clientXform = Transform(client);
+            if (clientXform.GridUid is not { } grid)
+                return ClientLookup;
+
+            _lookup.GetGridEntities(grid, ClientLookup);
+            return ClientLookup;
+        }
+
         public override void Update(float frameTime)
         {
             var query = EntityQueryEnumerator<ResearchServerComponent>();