using System;
using System.Globalization;
using System.Windows;
using System.Windows.Data;

namespace ScreenToGif.Util.Converters
{
    /// <summary>
    /// Converts the Alpha value to a Opacity Double and vice-versa.
    /// </summary>
    public class AlphaToOpacity : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (!(value is long cent))
                return DependencyProperty.UnsetValue;

            return cent / 255F;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (!(parameter is double parameterString) || value?.Equals(false) == true)
                return DependencyProperty.UnsetValue;

            return parameter;
        }
    }
}