Theme scheduler for Windows 10 Dark and Light mode based on sunset and sunrise time's, also includes a simple installer

install-theme-scheduler.ps1

New-Item -Path $env:LOCALAPPDATA -Name "Scripts" -ItemType "directory"

$url = "https://gist.githubusercontent.com/FreekBloemhof/d10639d63e37ff08356362096e7b1647/raw/3dfa848af8a3d94bf9868f866d31d657e3f5e6c5/theme-scheduler.ps1"

$WebClient = New-Object System.Net.WebClient
$WebClient.DownloadFile($url,"%LocalAppData%\Scripts\theme-scheduler.ps1")

$Path = $env:LOCALAPPDATA + "\Scripts\"
$output = [IO.Path]::Combine($Path, "theme-scheduler.ps1")
    
Write-Host "Downloading theme-scheduler from $url to path " $Path -ForegroundColor Green 
    
#Download file
(New-Object System.Net.WebClient).DownloadFile($url, $output)

# Change these three variables to whatever you want
$jobname = "Theme Scheduler"
$script =  $env:LOCALAPPDATA + "\Scripts\theme-scheduler.ps1"
$repeat = (New-TimeSpan -Minutes 5)
 
# The script below will run as the specified user (you will be prompted for credentials)
# and is set to be elevated to use the highest privileges.
# In addition, the task will run every 5 minutes or however long specified in $repeat.
$scriptblock = [scriptblock]::Create($script)
$trigger = New-JobTrigger -Once -At (Get-Date).Date -RepeatIndefinitely -RepetitionInterval $repeat
$msg = "Enter the username and password that will run the task"; 
$credential = $Host.UI.PromptForCredential("Task username and password",$msg,"$env:userdomain\$env:username",$env:userdomain)
 
$options = New-ScheduledJobOption -RunElevated -ContinueIfGoingOnBattery -StartIfOnBattery
Register-ScheduledJob -Name $jobname -ScriptBlock $scriptblock -Trigger $trigger -ScheduledJobOption $options -Credential $credential -RunNow

theme-scheduler.ps1

# Note: Make sure location services are enabled for apps, otherwise the script won't work.

Add-Type -AssemblyName System.Device
$GeoWatcher = New-Object System.Device.Location.GeoCoordinateWatcher
$GeoWatcher.Start()

function Get-UtcToDateTime($DateStr)
{
    $Date = [DateTime]::Parse($DateStr)
    [DateTime]::SpecifyKind($Date, [DateTimeKind]::Utc)
}

Function Get-UtcToLocalTime($UtcTime){
    $TimeZone = Get-TimeZone
    $LocalTime = [System.TimeZoneInfo]::ConvertTimeFromUtc($UtcTime, $TimeZone)
    Return $LocalTime
}

Function Enable-LightTheme($Enable) {
    New-ItemProperty -Path HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\Themes\Personalize -Name AppsUseLightTheme -Value $Enable -Type Dword -Force
}

while (($GeoWatcher.Status -ne 'Ready') -and ($GeoWatcher.Permission -ne 'Denied')) {
    Start-Sleep -Milliseconds 100
}  

if ($GeoWatcher.Permission -eq 'Denied'){
    Write-Error 'Access Denied for Location Information, you need to allow apps to access your location.'
    exit
}

$Location = $GeoWatcher.Position.Location
$Request = "https://api.sunrise-sunset.org/json?lat=" + $Location.Latitude + "&lng=" + $Location.Longitude

$Response = Invoke-WebRequest $Request | ConvertFrom-Json | Select results

$CurrentDateTime = Get-Date

$SunRiseDateTime = Get-UtcTolocalTime(Get-UtcToDateTime($Response.results.sunrise))
$SunSetDateTime = Get-UtcTolocalTime(Get-UtcToDateTime($Response.results.sunset))

if ($CurrentDateTime -gt $SunRiseDateTime -And $CurrentDateTime -lt $SunSetDateTime)
{
    Enable-LightTheme(1)
} else {
    Enable-LightTheme(0)
}