using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;

namespace Tango.SharedUI.Converters
{
    /// <summary>
    /// Converts a byte array size to friendly size string.
    /// </summary>
    /// <seealso cref="System.Windows.Data.IValueConverter" />
    public class ByteArrayToFileSizeConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value != null)
            {
                return BytesToString(System.Convert.ToInt64(value));
            }
            else
            {
                return null;
            }
        }

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

        static String BytesToString(long byteCount)
        {
            string[] suf = { "B", "KB", "MB", "GB", "TB", "PB", "EB" }; //Longs run out around EB
            if (byteCount == 0)
                return "0" + suf[0];
            long bytes = Math.Abs(byteCount);
            int place = System.Convert.ToInt32(Math.Floor(Math.Log(bytes, 1024)));
            double num = Math.Round(bytes / Math.Pow(1024, place), 1);
            return (Math.Sign(byteCount) * num).ToString() + " " + suf[place];
        }
    }
}