Refactor update file discovery and cache comparison

Improves the reliability of finding update files (CU, CUP, .NET) by first using the exact filename from the update metadata. The script now only falls back to searching by KB article ID if the primary method fails.

Additionally, this enhances the VHDX cache lookup logic. The comparison now uses update file names extracted directly from their URLs, ensuring a more accurate match against the cached configuration.

FFUDevelopment/BuildFFUVM.ps1

@@ -4651,7 +4651,13 @@ try {
             $vhdxJsons = @(Get-ChildItem -File -Path $VHDXCacheFolder -Filter '*_config.json' | Sort-Object -Property CreationTime -Descending)
             WriteLog "Found $($vhdxJsons.Count) cached VHDX config files"
             
-            $requiredUpdateNames = $requiredUpdates.Name | Sort-Object
+            # Extract file names from URLs for comparison
+            $requiredUpdateFileNames = @()
+            foreach ($update in $requiredUpdates) {
+                $fileName = ($update.Url -split '/')[-1]
+                $requiredUpdateFileNames += $fileName
+            }
+            $requiredUpdateFileNames = $requiredUpdateFileNames | Sort-Object
 
             foreach ($vhdxJson in $vhdxJsons) {
                 try {
@@ -4669,7 +4675,7 @@ try {
                         $cachedUpdateNames = $vhdxCacheItem.IncludedUpdates.Name | Sort-Object
                     }
                     
-                    if ((Compare-Object -ReferenceObject $requiredUpdateNames -DifferenceObject $cachedUpdateNames).Length -gt 0) {
+                    if ((Compare-Object -ReferenceObject $requiredUpdateFileNames -DifferenceObject $cachedUpdateNames).Length -gt 0) {
                         WriteLog 'IncludedUpdates mismatch, continuing'
                         continue
                     }
@@ -4722,30 +4728,30 @@ try {
             WriteLog "Latest SSU identified as $SSUFilePath"
         }
         if ($cuUpdateInfos.Count -gt 0) {
-            $CUFileName = (Get-ChildItem -Path $KBPath -Filter "*$cuKbArticleId*" -Recurse | Select-Object -First 1).Name
-            if (-not $CUFileName) {
-                WriteLog "Could not find CU file containing '$cuKbArticleId'. This can happen with Checkpoint CUs. Will try to find the most likely candidate from the update info list."
-                $CUFileName = ($cuUpdateInfos | Where-Object { $_.Name -match $cuKbArticleId } | Select-Object -First 1).Name
-                if (-not $CUFileName) {
-                    WriteLog "Could not determine correct CU file from update info list. Using first in list as fallback."
+            # Use the actual downloaded file name from the update info
             $CUFileName = $cuUpdateInfos[0].Name
-                }
-            }
             $CUPath = (Get-ChildItem -Path $KBPath -Filter $CUFileName -Recurse).FullName
+            if (-not $CUPath) {
+                # If exact match fails, try to find by KB article ID
+                $CUPath = (Get-ChildItem -Path $KBPath -Filter "*$cuKbArticleId*" -Recurse | Select-Object -First 1).FullName
+                if ($CUPath) {
+                    $CUFileName = Split-Path $CUPath -Leaf
+                }
+            }
             WriteLog "Latest CU identified as $CUPath"
         }
         if ($cupUpdateInfos.Count -gt 0) {
-            $CUPFileName = (Get-ChildItem -Path $KBPath -Filter "*$cupKbArticleId*" -Recurse | Select-Object -First 1).Name
-            if (-not $CUPFileName) {
-                WriteLog "Could not find CU file containing '$cupKbArticleId'. This can happen with Checkpoint CUs. Will try to find the most likely candidate from the update info list."
-                $CUPFileName = ($cupUpdateInfos | Where-Object { $_.Name -match $cupKbArticleId } | Select-Object -First 1).Name
-                if (-not $CUPFileName) {
-                    WriteLog "Could not determine correct CU file from update info list. Using first in list as fallback."
+            # Use the actual downloaded file name from the update info
             $CUPFileName = $cupUpdateInfos[0].Name
-                }
-            }
             $CUPPath = (Get-ChildItem -Path $KBPath -Filter $CUPFileName -Recurse).FullName
-            WriteLog "Latest CU identified as $CUPPath"
+            if (-not $CUPPath) {
+                # If exact match fails, try to find by KB article ID
+                $CUPPath = (Get-ChildItem -Path $KBPath -Filter "*$cupKbArticleId*" -Recurse | Select-Object -First 1).FullName
+                if ($CUPPath) {
+                    $CUPFileName = Split-Path $CUPPath -Leaf
+                }
+            }
+            WriteLog "Latest Preview CU identified as $CUPPath"
         }
         if ($netUpdateInfos.Count -gt 0 -or $netFeatureUpdateInfos.Count -gt 0) {
             if ($isLTSC -and $WindowsRelease -in 2016, 2019, 2021) {
@@ -4753,13 +4759,16 @@ try {
                 WriteLog ".NET updates for LTSC are in $NETPath"
             }
             else {
-                $NETFileName = (Get-ChildItem -Path $KBPath -Filter "*$netKbArticleId*" -Recurse | Select-Object -First 1).Name
-                if (-not $NETFileName) {
-                    WriteLog "Could not find .NET file containing '$netKbArticleId'. Using first in list as fallback."
-                    $NETFileName = ($netUpdateInfos | Where-Object { $_.Name -match $netKbArticleId } | Select-Object -First 1).Name
-                    if (-not $NETFileName) { $NETFileName = $netUpdateInfos[0].Name }
-                }
+                # Use the actual downloaded file name from the update info
+                $NETFileName = $netUpdateInfos[0].Name
                 $NETPath = (Get-ChildItem -Path $KBPath -Filter $NETFileName -Recurse).FullName
+                if (-not $NETPath) {
+                    # If exact match fails, try to find by KB article ID
+                    $NETPath = (Get-ChildItem -Path $KBPath -Filter "*$netKbArticleId*" -Recurse | Select-Object -First 1).FullName
+                    if ($NETPath) {
+                        $NETFileName = Split-Path $NETPath -Leaf
+                    }
+                }
                 WriteLog "Latest .NET Framework identified as $NETPath"
             }
         }
@@ -4815,18 +4824,18 @@ try {
                     # Seems to be because of the registry being mounted per dism.log
                     Add-WindowsPackage -Path $WindowsPartition -PackagePath $SSUFilePath | Out-Null
                     WriteLog "SSU added to $WindowsPartition"
-                    WriteLog "Removing $SSUFilePath"
-                    Remove-Item -Path $SSUFilePath -Force | Out-Null
-                    WriteLog 'SSU removed'
+                    # WriteLog "Removing $SSUFilePath"
+                    # Remove-Item -Path $SSUFilePath -Force | Out-Null
+                    # WriteLog 'SSU removed'
                 }
                 if ($WindowsRelease -in 2016, 2019, 2021 -and $isLTSC) {
                     WriteLog "WindowsRelease is $WindowsRelease and is $WindowsSKU, adding SSU first"
                     WriteLog "Adding SSU to $WindowsPartition"
                     Add-WindowsPackage -Path $WindowsPartition -PackagePath $SSUFilePath | Out-Null
                     WriteLog "SSU added to $WindowsPartition"
-                    WriteLog "Removing $SSUFilePath"
-                    Remove-Item -Path $SSUFilePath -Force | Out-Null
-                    WriteLog 'SSU removed'
+                    # WriteLog "Removing $SSUFilePath"
+                    # Remove-Item -Path $SSUFilePath -Force | Out-Null
+                    # WriteLog 'SSU removed'
                 }
                 # Break out CU and NET updates to be added separately to abide by Checkpoint Update recommendations
                 if ($UpdateLatestCU) {