param(
      [CmdletBinding(DefaultParameterSetName="OU")]
      [Parameter(
            ParameterSetName="Computer",
            ValueFromPipeline=$true,
            ValueFromPipelineByPropertyName=$true)]
      [string[]]$ComputerName,

      [Parameter(ParameterSetName="OU")]
      [string]$SearchBase = "OU=Target,OU=Stations,DC=hagatorn,DC=local",

      [Parameter(ParameterSetName="Computer")]
      [Parameter(ParameterSetName="OU")]
      [string]$Idletime = 1440, #1 Day

      [Parameter(ParameterSetName="Computer")]
      [Parameter(ParameterSetName="OU")]
      [switch]$disconnected = $true,

      [Parameter(ParameterSetName="Computer")]
      [Parameter(ParameterSetName="OU")]
      [switch]$idle = $true,

      [Parameter(ParameterSetName="OU")]
      [switch]$All
)

Write-verbose ("Param Set: "+($psCmdlet.ParameterSetName))
if($psCmdlet.ParameterSetName -eq "OU"){
    $targetComputers = Get-ADComputer -filter '*' -SearchBase $SearchBase
}
else{
    $targetComputers = New-Object psobject -Property @{Name = $ComputerName}
}


$command = {
     param(
        [CmdletBinding()]
        [string]$Idletime,
        [switch]$disconnected,
        [switch]$idle
    )
    function Get-LoggedOnUser{
            param(
                [CmdletBinding()]
                [Parameter(ValueFromPipeline=$true,
                           ValueFromPipelineByPropertyName=$true)]
                [string[]]$ComputerName = 'localhost'
            )
            begin {
                $ErrorActionPreference = 'Stop'
            }

            process {
                foreach ($Computer in $ComputerName) {
                    try {
                        quser /server:$Computer 2>&1 | Select-Object -Skip 1 | ForEach-Object {
                            $CurrentLine = $_.Trim() -Replace '\s+',' ' -Split '\s'
                            $HashProps = @{
                                UserName = $CurrentLine[0]
                                ComputerName = $Computer
                            }

                            # If session is disconnected different fields will be selected
                            if ($CurrentLine[2] -eq 'Disc') {
                                    $HashProps.SessionName = $null
                                    $HashProps.Id = $CurrentLine[1]
                                    $HashProps.State = $CurrentLine[2]
                                    $HashProps.IdleTime = $CurrentLine[3]
                                    $HashProps.LogonTime = $CurrentLine[4..6] -join ' '
                                    $HashProps.LogonTime = $CurrentLine[4..($CurrentLine.GetUpperBound(0))] -join ' '
                            } else {
                                    $HashProps.SessionName = $CurrentLine[1]
                                    $HashProps.Id = $CurrentLine[2]
                                    $HashProps.State = $CurrentLine[3]
                                    $HashProps.IdleTime = $CurrentLine[4]
                                    $HashProps.LogonTime = $CurrentLine[5..($CurrentLine.GetUpperBound(0))] -join ' '
                            }

                            New-Object -TypeName PSCustomObject -Property $HashProps |
                            Select-Object -Property UserName,ComputerName,SessionName,Id,State,IdleTime,LogonTime,Error
                        }
                    } catch {
                        New-Object -TypeName PSCustomObject -Property @{
                            ComputerName = $Computer
                            Error = $_.Exception.Message
                        } | Select-Object -Property UserName,ComputerName,SessionName,Id,State,IdleTime,LogonTime,Error
                    }
                }
            }
    }

    function Parse-Time{
    param(
        [CmdletBinding()]

        [ValidatePattern('^(((?<days>[0-9]+)\+)?((?<hours>[0-9]{1,2}):))?(?<mins>[0-9]{1,2})$')]
        [string]$quserTimeString

    )

    $quserTimeString -match '^(((?<days>[0-9]+)\+)?((?<hours>[0-9]{1,2}):))?(?<mins>[0-9]{1,2})$' | Out-Null

    [Timespan]::new($Matches.days, $Matches.hours, $Matches.mins, 0)


    }

    $idlemins = @{Name = "TotalIdleMinutes" ; Expression = {(Parse-Time $_.IdleTime).TotalMinutes} }

    try{
        Get-LoggedOnUser |
            ?{$_.Error -ne "No User exists for *"} |
            select *, $idlemins |
            %{ if( $_.State -eq "Disc"){

                    Write-Output ($env:computername+": "+$_.Username+" disconnected and idle for "+$_.TotalIdleMinutes+" Mins")
                    if($disconnected){Write-Output ( $_.id+" | % {Logoff `$_}")}

                }elseif($_.IdleTime -ne "none"  -and $_.TotalIdleMinutes -gt $Idletime)
                {

                    Write-Output ($env:computername+": "+$_.Username+" idle for "+$_.TotalIdleMinutes+" Mins")

                    if($idle){ Write-Output ( $_.id+" | % {Logoff `$_}")}

                }
                else{
                    Write-Output ($env:computername+": "+$_.Username+" is active")
                }
        }
    }
    catch [System.Management.Automation.RuntimeException]{
            Write-warning "Error Executing Get-LoggedOnUser on $env:computername"
            $_
    }

}

$targetComputers.name |
    %{

            try{

                invoke-command -computer $_ -ErrorAction Stop -command $command -ArgumentList $Idletime,$disconnected,$idle

            }

            catch [System.Management.Automation.RuntimeException]{

                Write-warning ("Error Connecting to "+($_.TargetObject))

            }

    }