[PRTG] Read Windows Cert Store

param(
    [string]$Thumb = "",
    [string]$ComputerName = "",
    [string]$UserName = '',
    <# use single quotes for password character escaping #>
    [string]$Password = '',
    [string]$Location = "",
    [switch]$GetCerts,
    [switch]$Verbose
)
$elapsed = [System.Diagnostics.Stopwatch]::StartNew()
# This will create the credential
# object that is used to get the certificates
#######################################
function createCredentials{
        # Generate Credentials Object first
        $SecPasswd  = ConvertTo-SecureString $Password -AsPlainText -Force
        $Credentials= New-Object System.Management.Automation.PSCredential ($Username, $secpasswd)
        return $Credentials
}

# This will read the certificates from the remote host
######################################################
function retrieveCertificates{

    $Credentials = (createCredentials);

    try {
        if($verbose) { Write-Host ("Searching for certificates with thumbprint {0} under {1} on {2}" -f $Thumb,$Location,$ComputerName) }
        if((($env:COMPUTERNAME) -ne $ComputerName)){
                    if($verbose) { Write-Host "Not querying localhost, invoking command..." }
                    $Certificates = (Invoke-Command -ComputerName $ComputerName -ScriptBlock { param($Location); Get-ChildItem -Path "$($Location)" } -Credential $Credentials -ArgumentList @($Location))
        }
        else{ $Certificates = (Get-ChildItem -Path $Location ) }

        if($verbose) {
            Write-Host ("Certificates loaded! Found {0} certificates." -f $Certificates.Count)
            $Certificates | Select-Object Thumbprint,Subject,FriendlyName | ft | Out-Host -Paging;
        }

        return $Certificates
    }
    catch {
        $ErrorMessage = $_.Exception.Message
        Write-Host "0:Error checking Remote - CA";
        if($verbose) { Write-Host  $ErrorMessage; }
    }

}

# This function will check the certificates and
# search for either all of them or for one with a matching thumbprint
##############################
function evaluateCertificates{
    # Get the current date
    $TimeStamp = (Get-Date)

    $Certificates = (retrieveCertificates);
    if($GetCerts) { $Certificates | Select-Object Thumbprint,Subject,FriendlyName | ft | Out-Host -Paging; exit 0; }

    # Filter for a specific thumb, create output
    $SpecificCertificate = ( $Certificates | Where-Object { $_.Thumbprint -Match $Thumb } )
    if($verbose) { Write-Host ("Found {0} certificates that match. If multiple certificates are found, please specify the location!" -f $SpecificCertificate.Count); }

    $TimeSpan = $SpecificCertificate.NotAfter - $TimeStamp
    Write-Host ("{0}:Cert with thumb {1} expires in {0} days" -f $TimeSpan.Days, $SpecificCertificate.Thumbprint)
    if($verbose){  Write-Host "Execution time: $($elapsed.Elapsed.TotalSeconds.ToString()) seconds" }
    exit 0;
}

evaluateCertificates;