#Author: Chris Kennedy
#Description: Configures Vive driver power save settings so that the driver is never put to sleep.
#Version History:
    #1.0 [2018-07-25] - Initial Release

Clear-Host

#Check to see if this is running as administrator, and if not provide a UAC message and relaunch script.
$currentPrincipal = New-Object Security.Principal.WindowsPrincipal([Security.Principal.WindowsIdentity]::GetCurrent())
if (!($currentPrincipal.IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator))) {
    Write-Host "I have detected that the script is not running as an Administrator."
    Write-Host "I will relaunch the script. If you see a prompt from 'User Account Control' asking if you want to allow PowerShell to make changes, you must click 'Yes'."
    Pause
    Start-Process -FilePath PowerShell -Verb runas -ArgumentList "-File $($PSCommandPath) -ExecutionPolicy Bypass"
    Exit
}

Write-Host "It should take just a moment to find the proper key."

#Gathers all the subkeys
$registryRoot = Get-ChildItem "HKLM:\SYSTEM\CurrentControlSet\Control\Class\{4d36e96c-e325-11ce-bfc1-08002be10318}" -ErrorAction Ignore

#Iterates through each subkey so we can determine if we need to touch it.
foreach ($subkey in $registryRoot) {
    $driverKey = Get-ItemProperty -Path $subkey.PSPath

    #The only one we want to change is the one for NVIDIA HD Audio
    if ($driverKey.DriverDesc -eq "NVIDIA High Definition Audio") {
        Write-Host "NVIDIA Driver located, setting proper values."
        $powerKey = Get-ItemProperty -PSPath "$($subkey.PSPath)\PowerSettings"

        try {
            Set-ItemProperty -Path $powerKey.PSPath -Name ConservationIdleTime -Value ([byte[]](0xFF, 0xFF, 0xFF, 0xFF))
            Set-ItemProperty -Path $powerKey.PSPath -Name PerformanceIdleTime -Value ([byte[]](0xFF, 0xFF, 0xFF, 0xFF))
            Set-ItemProperty -Path $powerKey.PSPath -Name IdlePowerState -Value ([byte[]](0x00, 0x00, 0x00, 0x00))
            Write-Host "Successfully configured the registry, a reboot may be required for changes to take effect."
            Pause
            Exit
        }
        catch {
            Write-Host "Failed - $($_.Exception.Message)"
        }
    }
}