WinnerRandomSelector

WinnerRandomSelector.cs

using System;
using System.Collections.Generic;
using System.IO;

namespace WinnerRandomSelector
{
    class Program
    {
        static void Main(string[] args)
        {
            var path = args.Length > 0 ? args[0] : "";
            var fixedTime = args.Length > 1 ? args[1] : "";
            var fixedTimeType = args.Length > 2 ? args[2] : "utc";
            if (!string.IsNullOrEmpty(path) && File.Exists(path))
            {
                var time = DateTime.UtcNow;
                if (!String.IsNullOrEmpty(fixedTime))
                {
                    time = DateTime.ParseExact(fixedTime, "yyyy-MM-dd@HH:mm:ss", System.Globalization.CultureInfo.InvariantCulture);
                    if (fixedTimeType == "local")
                        time = DateTime.SpecifyKind(time, DateTimeKind.Local).ToUniversalTime();
                }
                var seed = (Int32)(time.Subtract(new DateTime(1970, 1, 1))).TotalSeconds;
                var input = File.ReadAllText(path);
                var lines = new List<string>(input.Split(new char[] { ' ', '\t', ',', ';', '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries));
                var random = new Random(seed);
                var i = 0;
                while (lines.Count > 1)
                {
                    var index = random.Next() % lines.Count;
                    if (index >= 0 && index < lines.Count)
                    {
                        Console.WriteLine("LOSER #" + (++i) + ": " + lines[index]);
                        lines.RemoveAt(index);
                    }
                }
                Console.WriteLine("WINNER: " + lines[0]);
                Console.WriteLine("SEED: " + seed);
                Console.WriteLine("UTC TIME: " + time);
                Console.WriteLine("LOCAL TIME: " + DateTime.SpecifyKind(time, DateTimeKind.Utc).ToLocalTime());
            }
            Console.ReadKey();
        }
    }
}