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

namespace ENI2.Util
{
    public class ExpiryStateConverter : MarkupExtension, IValueConverter
    {
        private static ExpiryStateConverter _converter;

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            if (_converter == null)
            {
                _converter = new ExpiryStateConverter();
            }
            return _converter;
        }

        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (!(value is DateTime dt))
                return "Unknown";

            DateTime today = DateTime.Today;
            DateTime validUntil = dt.Date;

            if (validUntil < today)
                return "Expired";

            if (validUntil <= today.AddMonths(1))
                return "ExpiringSoon";

            return "Ok";
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}