function Show-ApplyModal {
    param (
        [Parameter(Mandatory=$false)]
        [System.Windows.Window]$Owner = $null,
        [Parameter(Mandatory=$false)]
        [bool]$RestartExplorer = $false
    )
    
    Add-Type -AssemblyName PresentationFramework,PresentationCore,WindowsBase | Out-Null
    
    $usesDarkMode = GetSystemUsesDarkMode
    
    # Determine owner window
    $ownerWindow = if ($Owner) { $Owner } else { $script:GuiWindow }
    
    # Show overlay if owner window exists
    $overlay = $null
    if ($ownerWindow) {
        try {
            $overlay = $ownerWindow.FindName('ModalOverlay')
            if ($overlay) {
                $ownerWindow.Dispatcher.Invoke([action]{ $overlay.Visibility = 'Visible' })
            }
        }
        catch { }
    }
    
    # Load XAML from file
    $xaml = Get-Content -Path $script:ApplyChangesWindowSchema -Raw
    $reader = [System.Xml.XmlReader]::Create([System.IO.StringReader]::new($xaml))
    try {
        $applyWindow = [System.Windows.Markup.XamlReader]::Load($reader)
    }
    finally {
        $reader.Close()
    }
    
    # Set owner to owner window if it exists
    if ($ownerWindow) {
        try {
            $applyWindow.Owner = $ownerWindow
        }
        catch { }
    }
    
    # Apply theme resources
    SetWindowThemeResources -window $applyWindow -usesDarkMode $usesDarkMode
    
    # Get UI elements
    $script:ApplyInProgressPanel = $applyWindow.FindName('ApplyInProgressPanel')
    $script:ApplyCompletionPanel = $applyWindow.FindName('ApplyCompletionPanel')
    $script:ApplyStepNameEl = $applyWindow.FindName('ApplyStepName')
    $script:ApplyStepCounterEl = $applyWindow.FindName('ApplyStepCounter')
    $script:ApplyProgressBarEl = $applyWindow.FindName('ApplyProgressBar')
    $script:ApplyCompletionTitleEl = $applyWindow.FindName('ApplyCompletionTitle')
    $script:ApplyCompletionMessageEl = $applyWindow.FindName('ApplyCompletionMessage')
    $script:ApplyCompletionIconEl = $applyWindow.FindName('ApplyCompletionIcon')
    $applyCloseBtn = $applyWindow.FindName('ApplyCloseBtn')
    $applyKofiBtn = $applyWindow.FindName('ApplyKofiBtn')
    $applyCancelBtn = $applyWindow.FindName('ApplyCancelBtn')
    
    # Initialize in-progress state
    $script:ApplyInProgressPanel.Visibility = 'Visible'
    $script:ApplyCompletionPanel.Visibility = 'Collapsed'
    $script:ApplyStepNameEl.Text = "Preparing..."
    $script:ApplyStepCounterEl.Text = "Preparing..."
    $script:ApplyProgressBarEl.Value = 0
    
    # Set up progress callback for ExecuteAllChanges
    $script:ApplyProgressCallback = {
        param($currentStep, $totalSteps, $stepName)
        $script:ApplyStepNameEl.Text = $stepName
        $script:ApplyStepCounterEl.Text = "Step $currentStep of $totalSteps"
        # Store current step/total in Tag properties for sub-step interpolation
        $script:ApplyStepCounterEl.Tag = $currentStep
        $script:ApplyProgressBarEl.Tag = $totalSteps
        # Show progress at the start of each step (empty at step 1, full after last step completes)
        $pct = if ($totalSteps -gt 0) { [math]::Round((($currentStep - 1) / $totalSteps) * 100) } else { 0 }
        $script:ApplyProgressBarEl.Value = $pct
        # Process pending window messages to keep UI responsive
        DoEvents
    }

    # Sub-step callback updates step name and interpolates progress bar within the current step
    $script:ApplySubStepCallback = {
        param($subStepName, $subIndex, $subCount)
        $script:ApplyStepNameEl.Text = $subStepName
        # Interpolate progress bar between previous step and current step
        $currentStep = [int]($script:ApplyStepCounterEl.Tag)
        $totalSteps = [int]($script:ApplyProgressBarEl.Tag)
        if ($totalSteps -gt 0 -and $subCount -gt 0) {
            $baseProgress = ($currentStep - 1) / $totalSteps
            $stepFraction = ($subIndex / $subCount) / $totalSteps
            $script:ApplyProgressBarEl.Value = [math]::Round(($baseProgress + $stepFraction) * 100)
        }
        DoEvents
    }
    
    # Run changes in background to keep UI responsive
    $applyWindow.Dispatcher.BeginInvoke([System.Windows.Threading.DispatcherPriority]::Background, [action]{
        try {
            ExecuteAllChanges
            
            # Restart explorer if requested
            if ($RestartExplorer -and -not $script:CancelRequested) {
                RestartExplorer
            }
            
            Write-Host ""
            if ($script:CancelRequested) {
                Write-Host "Script execution was cancelled by the user. Some changes may not have been applied."
            } else {
                Write-Host "All changes have been applied successfully!"
            }
            
            # Show completion state
            $script:ApplyProgressBarEl.Value = 100
            $script:ApplyInProgressPanel.Visibility = 'Collapsed'
            $script:ApplyCompletionPanel.Visibility = 'Visible'
            
            if ($script:CancelRequested) {
                $script:ApplyCompletionIconEl.Text = [char]0xE7BA
                $script:ApplyCompletionIconEl.Foreground = [System.Windows.Media.SolidColorBrush]::new([System.Windows.Media.ColorConverter]::ConvertFromString("#e8912d"))
                $script:ApplyCompletionTitleEl.Text = "Cancelled"
                $script:ApplyCompletionMessageEl.Text = "Script execution was cancelled by the user."
            } else {
                $script:ApplyCompletionTitleEl.Text = "Changes Applied"
                $script:ApplyCompletionMessageEl.Text = "Your clean system is ready. Thanks for using Win11Debloat!"
            }
            $applyWindow.Dispatcher.Invoke([System.Windows.Threading.DispatcherPriority]::Render, [action]{})
        }
        catch {
            Write-Host "Error: $($_.Exception.Message)"
            $script:ApplyInProgressPanel.Visibility = 'Collapsed'
            $script:ApplyCompletionPanel.Visibility = 'Visible'
            $script:ApplyCompletionIconEl.Text = [char]0xEA39
            $script:ApplyCompletionIconEl.Foreground = [System.Windows.Media.SolidColorBrush]::new([System.Windows.Media.ColorConverter]::ConvertFromString("#c42b1c"))
            $script:ApplyCompletionTitleEl.Text = "Error"
            $script:ApplyCompletionMessageEl.Text = "An error occurred while applying changes: $($_.Exception.Message)"
            $applyWindow.Dispatcher.Invoke([System.Windows.Threading.DispatcherPriority]::Render, [action]{})
        }
        finally {
            $script:ApplyProgressCallback = $null
            $script:ApplySubStepCallback = $null
        }
    })
    
    # Button handlers
    $applyCloseBtn.Add_Click({
        $applyWindow.Close()
    })

    $applyKofiBtn.Add_Click({
        Start-Process "https://ko-fi.com/raphire"
    })

    $applyCancelBtn.Add_Click({
        if ($script:ApplyCompletionPanel.Visibility -eq 'Visible') {
            # Completion state - just close
            $applyWindow.Close()
        } else {
            # In-progress state - request cancellation
            $script:CancelRequested = $true
        }
    })
    
    # Show dialog
    $applyWindow.ShowDialog() | Out-Null
    
    # Hide overlay after dialog closes
    if ($overlay) {
        try {
            $ownerWindow.Dispatcher.Invoke([action]{ $overlay.Visibility = 'Collapsed' })
        }
        catch { }
    }
}