[xml]$doc = Get-Content -LiteralPath 'C:\Users\tonycao\work\twincat3-auto-cli\TwinCAT_EL6695_Secondary\Logs\online_master.xml' -Encoding UTF8

Write-Host "=== EtherCAT Master XML keys ===" -ForegroundColor Cyan

# Dump all distinct element names (first level under TreeItem)
$doc.TreeItem | Get-Member -MemberType Property | ForEach-Object { Write-Host $_.Name }

# Look for online-related fields
$xmlText = $doc.OuterXml
$patterns = @('Link', 'Frame', 'Online', 'State', 'Status', 'OpState', 'AlState', 'Tx', 'Rx', 'Slave', 'DeviceState', 'Connected')
foreach ($p in $patterns) {
    $matches = [regex]::Matches($xmlText, "<$p[^>]*>[^<]*</$p>")
    if ($matches.Count -gt 0) {
        Write-Host "`nPattern $p found $($matches.Count) times:" -ForegroundColor Yellow
        foreach ($m in $matches | Select-Object -First 20) {
            Write-Host "  $($m.Value)"
        }
    }
}

# Look for any attribute containing State/Link/Frame
Write-Host "`n=== Attributes containing State/Link/Frame/Online ===" -ForegroundColor Cyan
$nodes = $doc.SelectNodes('//*')
foreach ($n in $nodes) {
    foreach ($a in $n.Attributes) {
        if ($a.Name -match 'State|Link|Frame|Online|Status|Op') {
            Write-Host "  $($n.Name)@$($a.Name)=$($a.Value)"
        }
    }
}

# Write clean XML to file for manual inspection
$doc.Save('C:\Users\tonycao\work\twincat3-auto-cli\TwinCAT_EL6695_Secondary\Logs\online_master_formatted.xml')
Write-Host "`nFormatted XML saved to online_master_formatted.xml" -ForegroundColor Green