yikes,

Classes/DBs/DBClasses/HwidDBClasses.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Collections.Generic;
+using LiteDB;
+
+namespace Vanadium.Classes.DBs.DBClasses
+{
+    public static class HwidDBClasses
+    {
+        /// <summary>
+        /// One machine, and every account that has ever reported from it.
+        /// <para>
+        /// The ban fields live on the record rather than in a second collection so that a
+        /// lookup by hwid answers both questions - who is this machine, and is it banned -
+        /// in a single read, on the path that runs for every client that checks in.
+        /// </para>
+        /// </summary>
+        public class HwidRecord
+        {
+            [BsonId]
+            public string Hwid { get; set; }
+            public List<long> PlayerIds { get; set; } = new();
+            public DateTime FirstSeen { get; set; }
+            public DateTime LastSeen { get; set; }
+
+            /// <summary>True while the machine itself is banned, separately from any account.</summary>
+            public bool IsBanned { get; set; }
+
+            /// <summary>Why. Required when banning; a blank reason makes a ban unreviewable.</summary>
+            public string BanReason { get; set; }
+
+            /// <summary>Player id of the moderator who issued it, or a system name.</summary>
+            public string BannedBy { get; set; }
+
+            public DateTime? BannedAt { get; set; }
+
+            /// <summary>Null bans permanently.</summary>
+            public DateTime? BanExpiresAt { get; set; }
+
+            /// <summary>
+            /// Accounts linked to the machine at the moment of the ban. A snapshot: it shows
+            /// what the moderator was looking at, which is not always what the link table
+            /// says later.
+            /// </summary>
+            public List<long> LinkedAtBan { get; set; } = new();
+
+            public bool BanIsActive(DateTime utcNow) =>
+                IsBanned && (BanExpiresAt == null || BanExpiresAt > utcNow);
+        }
+    }
+}