Param($KB)
if ($PSBoundParameters.Count -ne 1)  { Write-host "Error: -KB KB999999" ;exit 1}
$searchstr = "https://www.catalog.update.microsoft.com/Search.aspx?q=$($KB)"
$ret = Invoke-WebRequest -Uri $searchstr -UseBasicParsing
if ($ret.StatusCode -eq "200"){
  $pattern = @'
(?is)<a[^>]*onclick\s*=\s*(["']?)goToDetails\(\s*"([0-9A-Fa-f-]{36})"\s*\)\s*;?\s*\1[^>]*>\s*(.*?)\s*</a>
'@
  $items =
  [regex]::Matches($ret.Content, $pattern) |
  ForEach-Object {
    $guid = $_.Groups[2].Value
    $raw  = $_.Groups[3].Value
    $text = ($raw -replace '<[^>]+>','')
    $text = [System.Net.WebUtility]::HtmlDecode($text)
    $title = ($text -replace '\s+',' ').Trim()
    [pscustomobject]@{ UpdateId = $guid; Title = $title }
  } | Sort-Object UpdateId -Unique
  return $items
} else {
  Write-Error -Message "HTTP Status Code: $($ret.StatusCode)" 
  return $null
}

#https://catalog.s.download.windowsupdate.com/microsoftupdate/v6/wsusscan/wsusscn2.cab
$scancabPath = "$env:userprofile\Downloads\wsusscn2.cab"

$UpdateSession = New-Object -ComObject Microsoft.Update.Session
if (Test-Path $scancabPath) {
  $UpdateServiceManager = New-Object -ComObject Microsoft.Update.ServiceManager
  $UpdateService = $UpdateServiceManager.AddScanPackageService("Offline Sync Service", $scancabPath)
  $UpdateSearcher = $UpdateSession.CreateUpdateSearcher()
  $UpdateSearcher.ServerSelection = 3 # ssOthers
  $UpdateSearcher.ServiceID = [string] $UpdateService.ServiceID
} else {
  $UpdateSearcher = $UpdateSession.CreateUpdateSearcher()
}

$searchResult = $updateSearcher.Search("IsInstalled=0 and Type='Software' and IsHidden=0")
if ($searchResult.Updates.Count -eq 0) {
  Write-Host "There are no applicable updates."
} else {
  $i = 0
  foreach ($update in $searchResult.Updates){
    $i++
    Write-Host $i">" $update.Title
    Write-Host "   Suport URL:" $update.SupportUrl
    Write-Host "   Update ID :" $update.Identity.UpdateID
    Write-Host ""
  }
}

<#
.SYNOPSIS
This script obtains the Download URL and FILENAME of the Windows update program that have specified UpdateID.

.DESCRIPTION
This script web scrapes the DownloadDialog page of the Microsoft Update Catalog site (https://www.catalog.update.microsoft.com/DownloadDialog.aspx) to obtain the URL and FILENAME for UpdateID.

.INPUTS
The script takes UpdateId.

.OUTPUTS
List of URLs and FILENAMES for Updateid's update programs.

.EXAMPLE
# Get URL and FILENAME that have UpdateID "244bab40-f647-4394-bee0-b03f897404d8"
.\get-downloadlinks.ps1 -UpdateId "244bab40-f647-4394-bee0-b03f897404d8"

.EXAMPLE
# Get URL and FILENAME that have UpdateID "244bab40-f647-4394-bee0-b03f897404d8"
$links = .\get-downloadlinks.ps1 -UpdateId "244bab40-f647-4394-bee0-b03f897404d8"
$links.URL
$links.FILENAME

.NOTES 
This script is a sample. Use it at your own risk.

#>

Param($UpdateId)
if ($PSBoundParameters.Count -ne 1)  { Write-host "Error: -UpdateId <GUID>" ;exit 1}

$PostJson = @{size = 0; UpdateID = $UpdateId; UpdateIDInfo = $UpdateId} | ConvertTo-Json -Compress
$Body = @{UpdateIDs = "[$PostJson]"}
$ret = Invoke-WebRequest `
    -Uri 'https://www.catalog.update.microsoft.com/DownloadDialog.aspx' `
    -UseBasicParsing  `
    -Method Post `
    -ContentType 'application/x-www-form-urlencoded' `
    -Body $body

$pattern = "downloadInformation\[\d+\]\.files\[\d+\]\.url\s*=\s*'([^']+)'"

$items = [regex]::Matches($ret.Content, $pattern) |
  ForEach-Object {
    $url = $_.Groups[1].Value
    [pscustomobject]@{
      URL      = $url
      FileName = Split-Path $url -Leaf
    }
  } | Sort-Object URL -Unique

$items

Param($CsvPath, $PackageDir, $LogDir)
if ($PSBoundParameters.Count -ne 3)  { Write-host "Error: -CsvPath <path> -PackageDir <path> -LogDir <Path>" ;exit 1}
If ( -not (Test-Path $CsvPath)) { Write-host "Error: -CsvPath <path> does not exist." ;exit 1}
If ( -not (Test-Path $packagedir)) { Write-host "Error: -PackageDir <path> does not exist." ;exit 1}
If ( -not (Test-Path $LogDir)) { Write-host "Error: -LogDir <path> does not exist." ;exit 1}

# Keywords that are not downloaded based on part of the file name. 'KB9999999' is dummy (you can delete it).
# 'KB5043080' is a checkpoint cumulative update for Windows 11 24H2 and Windows Server 2025 or later, and does not require installation.
# Detail: https://learn.microsoft.com/ja-jp/windows/deployment/update/catalog-checkpoint-cumulative-updates
$ExcludeLists = 'KB5043080','KB9999999'

function Write-Log {
  param (
      [string]$Message,
      [string]$LogPath = "$env:TEMP\onlinepatch.log"
    )
  #Output to Console
  Write-Host $Message
  $timestamp = Get-Date -Format "yyyy-MM-dd HH:mm:ss"
  $entry = "[$timestamp] $Message"
  Add-Content -Path $LogPath -Value $entry
}

# for .\get-updateids.ps1
# for .\get-downloadLinks {
Set-Location -Path $PSScriptRoot

function Start-Download {
  param (
      [string]$downloaduri,
      [string]$PackageDir
    )
  $filename = Split-Path $downloaduri -Leaf
  if (Test-Path (Join-Path $PackageDir $filename)) {
    Write-Log -Message "File $($filename) has already beed downloaded. Skip download." -LogPath $LogPath
  } else {
    Write-Log -Message "Downloading $($filename) ..." -LogPath $LogPath
    if (Test-Path "$env:WINDIR\System32\curl.exe") {
      & curl.exe -L --fail --retry 3 --retry-delay 2 -o (Join-Path $PackageDir $filename) $downloaduri
    } else {
      $ProgressPreference = 'SilentlyContinue'
      Invoke-WebRequest -Uri $downloaduri -OutFile (Join-Path $PackageDir $filename) -UseBasicParsing
      $ProgressPreference = 'Continue'
    }
    if (Test-Path (Join-Path $PackageDir $filename)) {
      Write-Log -Message "Download completed." -LogPath $LogPath
    } else {
      Write-Log -Message "Download failed." -LogPath $LogPath
    }
  }
}

$LogPath = "$LogDir\downloadupdates.log"
if (Test-Path $logPath) {
  $logTime = (get-item $logPath).LastWriteTime
} else {
  $logTime = get-Date("1900/1/1")
}

Write-Log -Message "Start download-updates.ps1" -LogPath $LogPath
Write-Log -Message "Import CSV from $($CsvPath)" -LogPath $LogPath
$csvrows = Import-Csv -Path $CsvPath
Write-Log -Message "Found $($csvrows.Count) udpates." -LogPath $LogPath

foreach ($csvrow in $csvrows) {
  $KBID = $csvrow.KBId
  $TITLE = $csvrow.TITLE
  $HINTID = $csvrow.UpdateId
  $HINT = "NOTMATCHTITLE"
  if ($TITLE -match "Server") {
    $HINT = "Server"
  } elseif ($TITLE -match "x64-based") {
    $HINT = "x64-based"
  } elseif ($TITLE -match "arm64-based") {
    $HINT = "arm64-based"
  }
  $UpdateIds = .\Get-UpdateIds.ps1 -KB $KBID
  if ($UpdateIds.Count -eq 0) {
    Write-Log -Message "UpdateID corresponding to $($KBID) not found." -LogPath $LogPath
  } else {
    foreach ($UpdateId in $UpdateIds) {
      $DownloadID = ""
      if($UpdateId.UpdateId -eq $HINTID) {
        $DownloadId = $UpdateId.UpdateId
      } elseif($UpdateId.TITLE -match $HINT) {
        $DownloadId = $UpdateId.UpdateId
      }
      if ($DownloadId -ne "") {
        $downloadlinks = .\Get-DownloadLinks.ps1 -UpdateId $DownloadId
        if ($downloadlinks.Count -eq 0) {
          Write-Log -Message "DownloadLinks corresponding to $($KBID) : $($UpdateId.UpdateId) not found." -LogPath $LogPath 
        } else {
          foreach ($downloadlink in $downloadLinks) {
            if ($downloadlink.FileName | Select-String -Pattern $ExcludeLists -SimpleMatch -Quiet) {
              Write-Log -Message "Skip UpdateID: $($UpdateId.UpdateId) FileName $($downloadlink.FileName -replace '^(?s)(.{0,25}).*','$1') ... based on the ExcludeLists." -LogPath $LogPath
            } else {
              Start-Download -downloaduri $downloadlink.URL -PackageDir $PackageDir
            }
          }
        }
      } else {
          Write-Log -Message "Skip UpdateID: $($UpdateId.UpdateId) based on the hint (ID or Platform)." -LogPath $LogPath
      }
    }
  }
}

$logPath = "\\192.168.0.1\WUPackages\logs\wuscan_$(hostname).csv"
$scancabPath = "\\192.168.0.1\WUPackages\wsusscn2.cab"

if (Test-Path $scancabPath) {
  Write-Host "Scanning start using $scancabPath ..."
  Copy-Item $scancabPath "$env:Temp\mywsusscn2.cab"
  $scancabPath = "$env:Temp\mywsusscn2.cab"
  #pause
} else {
  Write-Host $scancabPath "not found. Nothing to do."
  #pause
  exit 1
}
$UpdateSession = New-Object -ComObject Microsoft.Update.Session
$UpdateServiceManager = New-Object -ComObject Microsoft.Update.ServiceManager
$UpdateService = $UpdateServiceManager.AddScanPackageService("Offline Sync Service", $scancabPath)
$UpdateSearcher = $UpdateSession.CreateUpdateSearcher()

Write-Host "Searching for updates..."
$UpdateSearcher.ServerSelection = 3 # ssOthers
$UpdateSearcher.ServiceID = [string] $UpdateService.ServiceID
$SearchResult = $UpdateSearcher.Search("IsInstalled=0")
$Updates = $SearchResult.Updates
Remove-Item $scancabPath
If ($SearchResult.Updates.Count -eq 0) {
  Write-Host "There are no applicable updates."
  #pause
  exit 0
}
Write-Host "List of applicable items on the machine when using wssuscan.cab:"
$results = @()
For ($i = 0; $i -lt $SearchResult.Updates.Count; $i++) {
  $update = $SearchResult.Updates.Item($i)
  Write-Host ($i + 1) "> " $update.Title
  $kbID = ""
  if ($update.Title -match 'KB\d{6,7}') {
    $kbID = $matches[0]
  }
  $results += [PSCustomObject]@{
    Title = $update.Title
    KBId = $kbID
    UpdateId = $update.Identity.UpdateID
    Support = "https://support.microsoft.com/kb/" + $kbID.Substring(2)
    Catalog = "https://catalog.update.microsoft.com/Search.aspx?q=" + $kbID
  }
}

$results | Export-Csv -Path $logPath -NoTypeInformation -Encoding UTF8
#pause
exit 0