winutil/functions/private/Invoke-WinUtilFontScaling.ps1

function Invoke-WinUtilFontScaling {
    <#

    .SYNOPSIS
        Applies UI and font scaling for accessibility

    .PARAMETER ScaleFactor
        Sets the scaling from 0.75 and 2.0.
        Default is 1.0 (100% - no scaling)

    .EXAMPLE
        Invoke-WinUtilFontScaling -ScaleFactor 1.25
        # Applies 125% scaling
    #>

    param (
        [double]$ScaleFactor = 1.0
    )

    # Validate if scale factor is within the range
    if ($ScaleFactor -lt 0.75 -or $ScaleFactor -gt 2.0) {
        Write-Warning "Scale factor must be between 0.75 and 2.0. Using 1.0 instead."
        $ScaleFactor = 1.0
    }

    # Define an array for resources to be scaled
    $fontResources = @(
        "FontSize",
        "ButtonFontSize",
        "HeaderFontSize",
        "TabButtonFontSize",
        "IconFontSize",
        "SettingsIconFontSize",
        "CloseIconFontSize",
        "AppEntryFontSize",
        "SearchBarTextBoxFontSize",
        "SearchBarClearButtonFontSize",
        "CustomDialogFontSize",
        "CustomDialogFontSizeHeader",
        "ConfigUpdateButtonFontSize",
        "CheckBoxBulletDecoratorSize"
    )

    # Apply scaling to each resource
    foreach ($resourceName in $fontResources) {
        try {
            # Get the default font size from the theme configuration
            $originalValue = $sync.configs.themes.shared.$resourceName
            if ($originalValue) {
                # Convert string to double since values are stored as strings
                $originalValue = [double]$originalValue
                # Calculates and applies the new font size
                $newValue = [math]::Round($originalValue * $ScaleFactor, 1)
                $sync.Form.Resources[$resourceName] = $newValue
                Write-Debug "Scaled $resourceName from original $originalValue to $newValue (factor: $ScaleFactor)"
            }
        }
        catch {
            Write-Warning "Failed to scale resource $resourceName : $_"
        }
    }

    # Update the font scaling percentage displayed on the UI
    if ($sync.FontScalingValue) {
        $percentage = [math]::Round($ScaleFactor * 100)
        $sync.FontScalingValue.Text = "$percentage%"
    }

    Write-Debug "Font scaling applied with factor: $ScaleFactor"
}