Whitelist player constraints (#13812)

Content.Server/Connection/ConnectionManager.cs

@@ -150,11 +150,21 @@ namespace Content.Server.Connection
                 return (ConnectionDenyReason.Ban, firstBan.DisconnectMessage, bans);
             }
 
-            if (_cfg.GetCVar(CCVars.WhitelistEnabled)
+            if (_cfg.GetCVar(CCVars.WhitelistEnabled))
-                && await _db.GetWhitelistStatusAsync(userId) == false
+            {
+                var min = _cfg.GetCVar(CCVars.WhitelistMinPlayers);
+                var max = _cfg.GetCVar(CCVars.WhitelistMaxPlayers);
+                var playerCountValid = _plyMgr.PlayerCount > min && _plyMgr.PlayerCount < max;
+
+                if (playerCountValid && await _db.GetWhitelistStatusAsync(userId) == false
                                      && adminData is null)
                 {
-                return (ConnectionDenyReason.Whitelist, Loc.GetString(_cfg.GetCVar(CCVars.WhitelistReason)), null);
+                    var msg = Loc.GetString(_cfg.GetCVar(CCVars.WhitelistReason));
+                    // was the whitelist playercount changed?
+                    if (min > 0 || max < int.MaxValue)
+                        msg += "\n" + Loc.GetString("whitelist-playercount-invalid", ("min", min), ("max", max));
+                    return (ConnectionDenyReason.Whitelist, msg, null);
+                }
             }
 
             return null;

Content.Shared/CCVar/CCVars.cs

@@ -940,6 +940,18 @@ namespace Content.Shared.CCVar
         public static readonly CVarDef<string> WhitelistReason =
             CVarDef.Create("whitelist.reason", "whitelist-not-whitelisted", CVar.SERVERONLY);
 
+        /// <summary>
+        ///     If the playercount is below this number, the whitelist will not apply.
+        /// </summary>
+        public static readonly CVarDef<int> WhitelistMinPlayers =
+            CVarDef.Create("whitelist.min_players", 0, CVar.SERVERONLY);
+
+        /// <summary>
+        ///     If the playercount is above this number, the whitelist will not apply.
+        /// </summary>
+        public static readonly CVarDef<int> WhitelistMaxPlayers =
+            CVarDef.Create("whitelist.max_players", int.MaxValue, CVar.SERVERONLY);
+
         /*
          * VOTE
          */

Resources/Locale/en-US/connection-messages.ftl

@@ -1,4 +1,13 @@
 whitelist-not-whitelisted = You are not whitelisted.
+
+# proper handling for having a min/max or not
+whitelist-playercount-invalid = {$min ->
+    [0] The whitelist for this server only applies below {$max} players.
+    *[other] The whitelist for this server only applies above {$min} {$max ->
+        [2147483647] -> players, so you may be able to join later.
+       *[other] -> players and below {$max} players, so you may be able to join later.
+    }
+}
 whitelist-not-whitelisted-rp = You are not whitelisted. To become whitelisted, visit our Discord (which can be found at https://spacestation14.io) and check the #rp-whitelist channel.
 
 command-whitelistadd-description = Adds the player with the given username to the server whitelist.