Linux Top for Windows - powershell

top.ps1

function top {
   if ($host -and $host.UI.SupportsVirtualTerminal) {
        Clear-Host
        $lines = $Host.UI.RawUI.WindowSize.Height
        $cols = $Host.UI.RawUI.WindowSize.Width
        [int]$min = 10
        $topCount = ($lines - $min)
        if ($lines -le $min) {
            $topCount = $lines 
        }
        $sortDesc = 'CPU'
        $pp = $ProgressPreference
        $ProgressPreference = "SilentlyContinue"
        try {
            while (1) {
                $info = get-computerinfo
                $pInuse = $info.OsTotalVisibleMemorySize - $info.OsFreePhysicalMemory
                $phys = [math]::round(($info.OsTotalVisibleMemorySize/1MB),2)
                $physuse = ($pInuse/$info.OsTotalVisibleMemorySize).toString("P")
                $cpuAv = (Get-CimInstance -ClassName win32_processor | Measure-Object -Property LoadPercentage -Average).Average
                write-host "system: $($info.CsCaption) uptime: $($info.OsUptime) OS version $($info.OsVersion) $($info.OSDisplayVersion)"
                write-host "process: $($info.OsNumberOfProcesses) users: $($info.OsNumberOfUsers) Sort: $($sortDesc.PadRight(7))"
                write-host "cpus: $($info.CsNumberOfLogicalProcessors) load: $($cpuAv)% Physical memory: $phys usage: $physUse"
                Get-Process | Sort-Object -desc $sortDesc | Select-Object -first $topCount | format-table 
                # if ($host.UI.RawUI.KeyAvailable) # doesn't work?
                if ([Console]::KeyAvailable)
                {
                    $key = $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
                    switch ($key.character) {
                        'c'{
                            $sortDesc = 'CPU'
                        }
                        'h' {
                            $sortDesc = 'Handles'
                        }
                        'n'{
                            $sortDesc = 'NPM'
                        }
                        'p' {
                            $sortDesc = 'PM'
                        }
                        'q'{
                            Clear-Host
                            return
                        }
                        'w'{
                            $sortDesc = 'WS'
                        }
                    }
                }
                else {                    
                    Start-Sleep 0.5
                }
                if (($Host.UI.RawUI.WindowSize.Height -ne $lines) -or 
                ($Host.UI.RawUI.WindowSize.Width -ne $cols)) {
                    Clear-Host
                    $lines = $Host.UI.RawUI.WindowSize.Height
                    $cols = $Host.UI.RawUI.WindowSize.Width
                    $topCount = ($lines - $min)
                    if ($lines -le $min) {
                        $topCount = $lines 
                    }
                }
                $host.UI.RawUI.CursorPosition = @{x = 0; y = 0}
            }
        }
        finally {
            $ProgressPreference = $pp 
        }
    }
}