yikes,

Guard/Server/Bans/MachineRecord.cs

@@ -0,0 +1,61 @@
+using System;
+using System.Collections.Generic;
+
+namespace VanadiumGuard.Server.Bans
+{
+    /// <summary>One machine as the service knows it, and every account seen on it.</summary>
+    public sealed class MachineRecord
+    {
+        public string Composite { get; set; } = string.Empty;
+
+        /// <summary>
+        /// The component hashes this machine reported. Kept so a ban can still recognise the
+        /// machine after one part is swapped and the composite changes.
+        /// </summary>
+        public Dictionary<string, string> Components { get; set; } = new Dictionary<string, string>(StringComparer.Ordinal);
+
+        /// <summary>Accounts that have opened a guard session from this machine.</summary>
+        public List<string> PlayerIds { get; set; } = new List<string>();
+
+        public DateTimeOffset FirstSeenUtc { get; set; }
+
+        public DateTimeOffset LastSeenUtc { get; set; }
+
+        /// <summary>Null when the machine is not banned. A lifted ban is removed, not flagged.</summary>
+        public MachineBan? Ban { get; set; }
+    }
+
+    /// <summary>
+    /// A hardware ban.
+    /// <para>
+    /// Every field here exists to answer a question someone will eventually ask about this
+    /// record: who did it, when, why, and until when. A ban list with no answers to those is
+    /// a liability rather than a tool - the appeal that cannot be evaluated gets denied by
+    /// default, which is the failure mode worth engineering against.
+    /// </para>
+    /// </summary>
+    public sealed class MachineBan
+    {
+        public string Reason { get; set; } = string.Empty;
+
+        /// <summary>Identity of the moderator or system that issued it, recorded verbatim.</summary>
+        public string IssuedBy { get; set; } = string.Empty;
+
+        public DateTimeOffset IssuedUtc { get; set; }
+
+        /// <summary>Null bans permanently.</summary>
+        public DateTimeOffset? ExpiresUtc { get; set; }
+
+        /// <summary>
+        /// The accounts linked to the machine when the ban was issued. A snapshot, so the
+        /// reviewer can see what the moderator was looking at rather than what the link
+        /// table happens to say today.
+        /// </summary>
+        public List<string> LinkedPlayerIdsAtIssue { get; set; } = new List<string>();
+
+        public bool IsActive(DateTimeOffset now)
+        {
+            return ExpiresUtc == null || ExpiresUtc > now;
+        }
+    }
+}