using System;
using System.Globalization;
using System.Text.RegularExpressions;
using BTCPayServer.Services.Rates;

namespace BTCPayServer
{
    public class CurrencyValue
    {
        static readonly Regex _Regex = new Regex("^([0-9]+(\\.[0-9]+)?)\\s*([a-zA-Z]+)$");
        public static bool TryParse(string str, out CurrencyValue value)
        {
            value = null;
            if (string.IsNullOrEmpty(str))
            {
                return false;
            }
            var match = _Regex.Match(str);
            if (!match.Success ||
                !decimal.TryParse(match.Groups[1].Value, NumberStyles.Any, CultureInfo.InvariantCulture, out var v))
                return false;

            var currency = match.Groups[match.Groups.Count - 1].Value.ToUpperInvariant();
            value = new CurrencyValue()
            {
                Value = v,
                Currency = currency
            };
            return true;
        }

        public decimal Value { get; set; }
        public string Currency { get; set; }

        public override string ToString()
        {
            return Value.ToString(CultureInfo.InvariantCulture) + " " + Currency;
        }

        public CurrencyValue Round(int divisibility) => new()
        {
            Value = Math.Round(Value, divisibility),
            Currency = Currency
        };
    }
}