<#
.SYNOPSIS
    Uninstalls Microsoft Windows App for all users (RMM / SYSTEM-safe).

.DESCRIPTION
    Removes the provisioned machine-wide MSIX package and uninstalls it
    for all existing user profiles on the machine.
#>
[CmdletBinding()]
param()

$ErrorActionPreference = 'Continue'
$PackageNameFilter = 'MicrosoftCorporationII.Windows365'

Write-Output "Starting removal of Windows App ($PackageNameFilter)..."

# 1. Remove Provisioned Package (Prevents automatic install for new users)
Write-Output "Checking for provisioned package..."
$provisioned = Get-AppxProvisionedPackage -Online -ErrorAction SilentlyContinue | 
    Where-Object { $_.DisplayName -like "$PackageNameFilter*" -or $_.PackageName -like "$PackageNameFilter*" }

if ($provisioned) {
    foreach ($pkg in $provisioned) {
        Write-Output "Removing provisioned package: $($pkg.PackageName)"
        Remove-AppxProvisionedPackage -Online -PackageName $pkg.PackageName | Out-Null
    }
} else {
    Write-Output "No provisioned package found."
}

# 2. Remove Appx Package for All Existing Users
Write-Output "Checking for per-user installations..."
$perUserPackages = Get-AppxPackage -AllUsers -Name "*$PackageNameFilter*" -ErrorAction SilentlyContinue

if ($perUserPackages) {
    # Select unique PackageFullNames to avoid redundant removal attempts
    $uniquePackages = $perUserPackages | Select-Object -ExpandProperty PackageFullName -Unique
    
    foreach ($pkgFullName in $uniquePackages) {
        Write-Output "Removing per-user package: $pkgFullName"
        Remove-AppxPackage -Package $pkgFullName -AllUsers | Out-Null
    }
} else {
    Write-Output "No per-user packages found."
}

# Verify Removal
$verifyProv = Get-AppxProvisionedPackage -Online -ErrorAction SilentlyContinue | Where-Object { $_.DisplayName -like "$PackageNameFilter*" }
$verifyUser = Get-AppxPackage -AllUsers -Name "*$PackageNameFilter*" -ErrorAction SilentlyContinue

if (-not $verifyProv -and -not $verifyUser) {
    Write-Output "Uninstall complete. Windows App has been removed successfully."
} else {
    Write-Warning "Uninstall finished, but some package remnants were still detected."
}