The UTILS of my Ticket Plugin (just some code I pilfered)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using Terraria;
using TShockAPI;

namespace TicketPlugin
{
    public class Utils
    {
        public static int UnixTimestamp()
        {
            int unixTime = (int)(System.DateTime.UtcNow - new System.DateTime(1970, 1, 1)).TotalSeconds;
            return unixTime;
        }

        public static TimeSpan ParseTimeSpan(string s)
        {
            const string Quantity = "quantity";
            const string Unit = "unit";

            const string Days = @"(d(ays?)?)";
            const string Hours = @"(h((ours?)|(rs?))?)";
            const string Minutes = @"(m((inutes?)|(ins?))?)";
            const string Seconds = @"(s((econds?)|(ecs?))?)";

            Regex timeSpanRegex = new Regex(
                string.Format(@"\s*(?<{0}>\d+)\s*(?<{1}>({2}|{3}|{4}|{5}|\Z))",
                              Quantity, Unit, Days, Hours, Minutes, Seconds),
                              RegexOptions.IgnoreCase);
            MatchCollection matches = timeSpanRegex.Matches(s);
            int l;
            TimeSpan ts = new TimeSpan();
            if (!Int32.TryParse(s.Substring(0, 1), out l))
            {
                return ts;
            }
            foreach (Match match in matches)
            {
                if (Regex.IsMatch(match.Groups[Unit].Value, @"\A" + Days))
                {
                    ts = ts.Add(TimeSpan.FromDays(double.Parse(match.Groups[Quantity].Value)));
                }
                else if (Regex.IsMatch(match.Groups[Unit].Value, Hours))
                {
                    ts = ts.Add(TimeSpan.FromHours(double.Parse(match.Groups[Quantity].Value)));
                }
                else if (Regex.IsMatch(match.Groups[Unit].Value, Minutes))
                {
                    ts = ts.Add(TimeSpan.FromMinutes(double.Parse(match.Groups[Quantity].Value)));
                }
                else if (Regex.IsMatch(match.Groups[Unit].Value, Seconds))
                {
                    ts = ts.Add(TimeSpan.FromSeconds(double.Parse(match.Groups[Quantity].Value)));
                }
                else
                {
                    ts = ts.Add(TimeSpan.FromMinutes(double.Parse(match.Groups[Quantity].Value)));
                }
            }
            return ts;
        }
    }
}