Intune Win32 App Maintenance Windows (Sort of)

<#
.SYNOPSIS
This PowerShell script determines if the current local time falls between 10 PM (22:00) and 5 AM (05:00).

.DESCRIPTION
Retrieves the current local time, extracts the hour, and checks if it is within the specified range.
Based on the result, it either proceeds with the installation or creates a scheduled task to sync Intune during the maintenance window (MW).
If the current time is within the MW, it outputs a message to install and exits with a success code.
If the current time is not within the MW, it outputs a message not to install, creates a scheduled task to run hourly from 11 PM for 5 hours syncing Intune policies, and exits with a non-success code.

Script Name: Intune_MaintenanceWindow.ps1
Author: John Marcum (PJM)
Date: 7/01/2024
Version: 1.0

.NOTES
This script can be used as a requirement rule for Intune Win32 app deployments to control installation timing based on maintenance windows.

# LEGAL DISCLAIMER
# This script is provided "as is" without any warranty of any kind, either express or implied, including but not limited to the implied warranties of merchantability, fitness for a particular purpose, or non-infringement. The entire risk as to the quality and performance of the script is with you.
# In no event shall the authors or copyright holders be liable for any claim, damages, or other liability, whether in an action of contract, tort, or otherwise, arising from, out of, or in connection with the script or the use or other dealings in the script.
# You should never run any script from the Internet without understanding its contents and effects. It is highly recommended that you thoroughly test the script in a safe environment before running it in production.
#>

# Get the current local time and extract the hour as integer
$currentTime = Get-Date -UFormat %R
$Hour = $currentTime.Split(":")[0]
$intHour = [int]$Hour

# Check if the current time is between 10 PM (22:00) and 5 AM (05:00)
$isInMaintenanceWindow = ($intHour -ge 22) -or ($intHour -le 5)

# Output the boolean value
Write-Host " Is in maintenance windows? $($isInMaintenanceWindow)"

# If the current time is within the maintenance window, exit with success code
if ($isInMaintenanceWindow) {
    # Current time is within the maintenance window. Install the app
    Write-Host "Install at $($intHour)"
    Write-Output -inputobject $isInMaintenanceWindow
    Exit 0
} else {
    # Current time is not within the maintenance window. Do not install the app. Create a scheduled task to sync Intune during the MW in hopes of getting the app to install when we want it to.
    Write-Host  "Do Not install at $($intHour)"
    
    # Define the folder and script path
    $folderPath = "C:\Temp"
    $scriptPath = "$folderPath\Invoke-IntuneSyncApp.ps1"

    # Ensure the folder exists
    if (-not (Test-Path -Path $folderPath)) {
        New-Item -Path $folderPath -ItemType Directory | Out-Null
    }

    # Check for and delete any old script
    if (Test-Path -Path $scriptPath) {
        Remove-Item -Path $scriptPath -Force
    }

    # Create the PowerShell script
    @"
$Shell = New-Object -ComObject Shell.Application
$Shell.open("intunemanagementextension://syncapp")
"@ | Set-Content -Path $scriptPath
    
    # Define the task name
    $taskName = "IntuneSyncApp"

    # Check if the scheduled task already exists
    $taskExists = Get-ScheduledTask -TaskName $taskName -ErrorAction SilentlyContinue

    if ($null -eq $taskExists) {
        try {
            # Define the start time
            $startTime = (Get-Date).Date.AddHours(23)  # 11 PM today

            # Create and register the task with the EndBoundary set after creation
            Register-ScheduledTask -TaskName $taskName -User "NT AUTHORITY\SYSTEM" -InputObject (
                (
                    New-ScheduledTask -Action (
                        New-ScheduledTaskAction -Execute 'powershell.exe' -Argument "-noprofile -executionpolicy bypass -File `"$scriptPath`""
                    ) -Trigger (
                        New-ScheduledTaskTrigger -Once -At $startTime
                    ) -Settings (
                        New-ScheduledTaskSettingsSet -AllowStartIfOnBatteries -DontStopIfGoingOnBatteries -StartWhenAvailable -ExecutionTimeLimit (New-TimeSpan -Hours 1) -DeleteExpiredTaskAfter (New-TimeSpan -Minutes 1)
                    )
                ) | % { $_.Triggers[0].EndBoundary = $startTime.AddMinutes(60).ToString('s') ; $_ } # Run through a pipe to set the end boundary of the trigger
            )

            Write-Host  "Scheduled task '$taskName' created successfully."
        } catch {
            Write-Host  "Failed to create scheduled task '$taskName'. Error: $_"
        }
    } else {
        Write-Host  "Scheduled task '$taskName' already exists. No action taken."
    }

    # Exit with false so the app does not install!
    Write-Output -inputobject $isInMaintenanceWindow
    Exit 0
}