Change laptop lid close action to "Do Nothing" when HDMI is connected

powercfg-lidaction.ps1

#
# Change a laptop's lid close action to "Do Nothing" for both AC and DC for the currently active power plan
# if an external display is connected via HDMI. If no HDMI is connected, set the close action to "Sleep" (default)
#
# Usage:
#
# ./powercfg-lidaction.ps1
#
# ./powercfg-lidaction.ps1 -Query
#

param (
    [switch] $Query,
    [string]$HDMIConnectedValue = 'Do Nothing',
    [string]$HDMIDisconnectedValue = 'Hibernate'
)


function lidActionFromString($actionString) {
    if ($actionString -eq "Sleep") {
        return 1
    } elseif ($actionString -eq "Hibernate") {
        return 2
    } elseif ($actionString -eq  "Shutdown") {
        return 3
    } elseif ($actionString -eq  "Do Nothing") {
        return 0
    }
    Write-Error "Invalid action string: ""$actionString"""
    Exit 1
}


function lidActionFromReg($actionRegValue) {
    if ($actionRegValue -eq "0x1") {
        return "Sleep"
    } elseif ($actionRegValue -eq "0x2") {
        return "Hibernate"
    } elseif ($actionRegValue -eq  "0x3") {
        return "Shutdown"
    } elseif ($actionRegValue -eq  "0x0") {
        return "Do Nothing"
    }
    Write-Error "Invalid action reg value: $actionRegValue"
    Exit 1
}


function setLidAction($action) {
    powercfg /setACvalueIndex scheme_current sub_buttons lidAction $action  # On wall power (AC)
    powercfg /setDCvalueIndex scheme_current sub_buttons lidAction $action  # On Battery power (DC)
    powercfg /setActive scheme_current
}


function getLidAction() {
    # Get the active scheme GUID
    $x = powercfg /GetActiveScheme
    $activeSchemeGuid = $x.split()[3]
    $subButtonsGuid = "4f971e89-eebd-4455-a8de-9e59040e7347"
    $lidActionGuid = "5ca83367-6e45-459f-a27b-476b1d01c936"

    # Query for the current powercfg setting for lid close action so we can toggle
    $x = reg query HKLM\System\CurrentControlSet\Control\Power\User\PowerSchemes\$activeSchemeGuid\$subButtonsGuid\$lidActionGuid /v ACSettingIndex
    return $x.split()[-2]
}


function isHDMIConnected() {
    # Video Output Technology: HDMI
    $D3DKMDT_VOT_HDMI = 5

    # Check if HDMI is connected
    $objWMi = get-wmiobject -namespace root\WMI -computername localhost -Query "Select * from WmiMonitorConnectionParams"

    foreach ($obj in $objWmi) {
        if ($obj.VideoOutputTechnology -eq $D3DKMDT_VOT_HDMI) {
            return $true
        }
    }
    return $false
}

$HDMIConnected = isHDMIConnected
$currentValue = getLidAction

if ($Query) {
    # Log current state
    $actionString = lidActionFromReg($currentValue)
    Write-Output "HDMIConnected: $HDMIConnected"
    Write-Output "Current setting: $actionString"
    Exit
}


if ($HDMIConnected) {
    Write-Output "Setting lid action to ""$HDMIConnectedValue""."
    $lidAction = lidActionFromString($HDMIConnectedValue)
    setLidAction($lidAction)
} else {
    Write-Output "Setting lid action to ""$HDMIDisconnectedValue""."
    $lidAction = lidActionFromString($HDMIDisconnectedValue)
    setLidAction($lidAction)
}