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/Typiqally/3ee013f1576ba3066a3e20c5a8c3aa01/raw/e21b2a7d205fdc2dc9c97a7de1dd91544d3e9569/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 Utc-ToDateTime($DateStr)
{
    $Date = [DateTime]::Parse($DateStr)
    [DateTime]::SpecifyKind($Date, [DateTimeKind]::Utc)
}

Function Utc-ToLocalTime($UtcTime){
    $CurrentTimeZone = (Get-WmiObject win32_timezone).StandardName
    $TimeZone = [System.TimeZoneInfo]::FindSystemTimeZoneById($CurrentTimeZone)
    $LocalTime = [System.TimeZoneInfo]::ConvertTimeFromUtc($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

$SunRiseDateTime = Utc-TolocalTime(Utc-ToDateTime($Response.results.sunrise))
$SunSetDateTime = Utc-TolocalTime(Utc-ToDateTime($Response.results.sunset))

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

Thank you for this script @Typiqally! Do you know how I can manually enter my region so it can follow the day/night cycle with that instead of giving my location? The less information I give Microsoft the better 😉

With the current API that is being used (https://sunrise-sunset.org/), I don’t think it’s possible.

You can also lookup the latitude and longitude of your region and use that. If you want to do this yourself, you do this by getting the latitude and longitude of the middle point of your region.