using System;

namespace AssortValidator.Common.Helpers
{
    public static class MathExtensions
    {
        public static int Round(this int i, int nearest)
        {
            if (nearest <= 0 || nearest % 10 != 0)
                throw new ArgumentOutOfRangeException(nameof(nearest), "Must round to a positive multiple of 10");

            return (i + (5 * nearest / 10)) / nearest * nearest;
        }

        public static int NumberSize(this int i)
        {
            switch (i.ToString().Length)
            {
                case 1:
                    return 1;
                case 2:
                    return 10;
                case 3:
                    return 100;
                case 4:
                    return 1000;
                case 5:
                    return 10000;
                case 6:
                    return 100000;
                case 7:
                    return 1000000;
            }

            return 10;
        }
    }
}