From c3e014446cb9850c8e7e897695f3570ef73dc223 Mon Sep 17 00:00:00 2001
From: jessikitty <jess.rogerson.29@outlook.com>
Date: Mon, 27 Apr 2026 16:07:48 +1000
Subject: [PATCH] v1.2.1 - Filter out devices without valid domain ID and not
 found in AD

---
 Features/DeviceCompareService.cs | 43 +++++++++++++++-----------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/Features/DeviceCompareService.cs b/Features/DeviceCompareService.cs
index facee3b..45005b1 100644
--- a/Features/DeviceCompareService.cs
+++ b/Features/DeviceCompareService.cs
@@ -26,20 +26,30 @@ namespace Disco.Plugins.ADCompare.Features
                 .Where(d => d.DeviceDomainId != null && d.DecommissionedDate == null)
                 .ToList();
 
-            summary.TotalDevices = devices.Count;
+            // Only process devices with a valid DOMAIN\ComputerName format
+            var validDevices = devices.Where(d => d.DeviceDomainId.Contains("\\")).ToList();
+            summary.TotalDevices = validDevices.Count;
+            summary.SkippedDevices = devices.Count - validDevices.Count;
 
-            foreach (var device in devices)
+            foreach (var device in validDevices)
             {
                 var result = CompareDevice(device);
+
+                // Skip devices not found in AD - only keep ones we can actually compare
+                if (!result.FoundInAD)
+                {
+                    summary.DevicesNotInAD++;
+                    continue;
+                }
+
                 summary.Results.Add(result);
             }
 
             summary.DevicesWithAssignment = summary.Results.Count(r => r.HasAssignment);
-            summary.DevicesNotInAD = summary.Results.Count(r => !r.FoundInAD);
             summary.DevicesMatched = summary.Results.Count(r => r.IsMatch);
-            summary.DevicesMismatched = summary.Results.Count(r => !r.IsMatch && r.FoundInAD);
+            summary.DevicesMismatched = summary.Results.Count(r => !r.IsMatch);
             summary.DevicesNoAssignment = summary.Results.Count(r => !r.HasAssignment);
-            summary.DevicesNoManagedBy = summary.Results.Count(r => r.FoundInAD && !r.HasManagedBy);
+            summary.DevicesNoManagedBy = summary.Results.Count(r => !r.HasManagedBy);
             summary.DevicesADDisabled = summary.Results.Count(r => r.ADAccountDisabled);
 
             return summary;
@@ -69,19 +79,15 @@ namespace Disco.Plugins.ADCompare.Features
                 result.FoundInAD = true;
                 result.ADAccountDisabled = adAccount.IsDisabled;
 
-                // Get the managedBy DN from the computer object
                 var managedByDN = adAccount.GetPropertyValue<string>("managedBy");
                 result.ADManagedByDN = managedByDN;
                 result.HasManagedBy = !string.IsNullOrEmpty(managedByDN);
 
-                // Extract display name from the CN portion of the DN for display
                 if (result.HasManagedBy)
                 {
                     result.ADManagedByDisplayName = ExtractCNFromDN(managedByDN);
                 }
 
-                // To compare correctly, look up the Disco assigned user in AD
-                // and compare their DN against the managedBy DN
                 string assignedUserDN = null;
                 if (result.HasAssignment)
                 {
@@ -91,23 +97,18 @@ namespace Disco.Plugins.ADCompare.Features
                         if (assignedUserAD != null)
                         {
                             assignedUserDN = assignedUserAD.DistinguishedName;
-                            result.ADManagedByUserId = device.AssignedUserId; // For display
+                            result.ADManagedByUserId = device.AssignedUserId;
                         }
                     }
-                    catch
-                    {
-                        // Can't look up assigned user in AD
-                    }
+                    catch { }
                 }
 
-                // Now compare: both have values -> compare DNs
                 if (!result.HasAssignment && !result.HasManagedBy)
                 {
                     result.IsMatch = true;
                 }
                 else if (result.HasAssignment && result.HasManagedBy && assignedUserDN != null)
                 {
-                    // Compare DN-to-DN (case insensitive)
                     result.IsMatch = string.Equals(assignedUserDN, managedByDN, StringComparison.OrdinalIgnoreCase);
                     if (result.IsMatch)
                     {
@@ -142,14 +143,14 @@ namespace Disco.Plugins.ADCompare.Features
                 return "Assigned in Disco but AD managedBy is empty";
 
             if (!result.HasAssignment && result.HasManagedBy)
-                return string.Format("Not assigned in Disco but AD managedBy is set to {0}", 
+                return string.Format("Not assigned in Disco but AD managedBy is set to {0}",
                     ExtractCNFromDN(result.ADManagedByDN));
 
             if (result.HasAssignment && result.HasManagedBy)
             {
                 var managedByName = ExtractCNFromDN(result.ADManagedByDN);
-                return string.Format("Different users: Disco={0} ({1}), AD managedBy={2}", 
-                    result.DiscoAssignedUserId, 
+                return string.Format("Different users: Disco={0} ({1}), AD managedBy={2}",
+                    result.DiscoAssignedUserId,
                     result.DiscoAssignedUserDisplayName ?? "?",
                     managedByName);
             }
@@ -157,10 +158,6 @@ namespace Disco.Plugins.ADCompare.Features
             return "Unknown mismatch";
         }
 
-        /// <summary>
-        /// Extract the CN value from a Distinguished Name.
-        /// e.g. "CN=Sue Lesnjak,OU=Teachers,..." -> "Sue Lesnjak"
-        /// </summary>
         private string ExtractCNFromDN(string dn)
         {
             if (string.IsNullOrEmpty(dn))