#Requires -Version 5.1

param(
    [Parameter(Mandatory=$true)][string]$Username,
    [Parameter(Mandatory=$true)][string]$Password,
    [Parameter(Mandatory=$true)][string]$FullName,
    [Parameter(Mandatory=$true)][string]$Description
)
$LogName = $MyInvocation.MyCommand
Log "Securing supplied password" -Name $LogName
Try { $Password = ConvertTo-SecureString $Password -AsPlainText -Force }
Catch { $_.Exception.Message | Log -Error -Name $LogName ; Exit }
If ( IsAdmin )
{
    If ( $(Get-CimInstance -ClassName Win32_OperatingSystem -Property ProductType | Select-Object -ExpandProperty ProductType) -ne "2" )
    {
        If ( $(Get-LocalUser -Name $User -ErrorAction SilentlyContinue) )
        {
            Log "Updating user: ${Username}" -Name $LogName
            Try { Get-LocalUser -Name $Username | Set-LocalUser -Password $Password -FullName $FullName -Description $Description -AccountNeverExpires -PasswordNeverExpires -UserMayNotChangePassword }
            Catch { $_.Exception.Message | Log -Error -Name $LogName ; Exit }
        }
        Else
        {
            Log "Creating user: ${Username}" -Name $LogName
            Try { New-LocalUser -Name $Username -Password $Password -FullName $FullName -Description $Description -AccountNeverExpires -PasswordNeverExpires -UserMayNotChangePassword }
            Catch { $_.Exception.Message | Log -Error -Name $LogName ; Exit }
        }
        If ( !($(Get-LocalGroupMember -Group "Administrators" -Member $Username -ErrorAction SilentlyContinue)) )
        {
            Log "Adding ""${Username}"" to local Administrators group" -Name $LogName
            Try { Add-LocalGroupMember -Group "Administrators" -Member $Username }
            Catch { $_.Exception.Message | Log -Error -Name $LogName ; Exit }
        }
    }
    Else { Log "The local user account ""${User}"" cannot be created on a domain controller" -Name $LogName }
}
Else { Log "Cannot create a local user account without administrative privileges" -Name $LogName }

#Get-ChildItem "HKLM:SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SpecialAccounts\UserList"

#[Environment]::Is64BitProcess