CsharpBuddy

CsharpBuddy.cs

/* DISCLAIMER:
 * This code is pure adhoc magic. NO WARRANTY or guarantees or
 * whatsoever! Use at your own risk!!
 */

using System;
using System.Collections.Generic;
using System.Linq;

namespace CsharpBuddy
{
    public class Input
    {
        public const string folks = @"
            empgrid,john
            empgrid,jane
            halive,mattheus
            halive,marcus
            halive,marc
            karp,mary
            karp,michelle
            karp,mickey
            best bogus,mogthendahl
            best bogus,nammus
            best bogus,elfie
            flex,ike";

        public const int seed = 1337;
        public const int groupSize = 2;
    }

    public class Program
    {
        static void Main(string[] args)
        {
            var seed = Input.seed;
            var input = Buddy.GetCollection();

            if (input.Count() % Input.groupSize != 0)
            {
                throw new InvalidOperationException("Input size not evenly divisible by group size!");
            }

            var groups = CreateGroups(input, seed++, Input.groupSize);

            for (var i = 1; i <= 1000 && groups.Any(g => g.Contains(null)); i++)
            {
                Console.WriteLine($"Iteration {i}");
                groups = CreateGroups(input, seed++, Input.groupSize);
            }

            Console.WriteLine(string.Join(Environment.NewLine, groups.Select(g => string.Join(" + ", g))));
            Console.ReadKey();
        }

        private static List<List<Buddy>> CreateGroups(ICollection<Buddy> input, int seed, int groupSize)
        {
            var random = new Random(seed);
            var groups = new List<List<Buddy>>();
            var people = input.OrderBy(p => p.ToString()).ToList();

            while (people.Any())
            {
                groups.Add(new List<Buddy>());

                for (int i = 0; i < groupSize; i++)
                {
                    var buddy = people.OrderBy(b => random.Next()).Where(p => !groups.Last().Select(b => b.Team).Contains(p.Team)).FirstOrDefault();
                    people.Remove(buddy);
                    groups.Last().Add(buddy);
                }
            }

            return groups;
        }
    }

    public class Buddy
    {
        public Buddy(string team, string name)
        {
            Team = team;
            Name = name;
        }

        public string Team { get; set; }
        public string Name { get; set; }

        public override string ToString()
        {
            return $"{Name} ({Team})";
        }

        public static ICollection<Buddy> GetCollection()
        {
            return Input.folks
                .Split(new[] { "\r\n", "\r", "\n" }, StringSplitOptions.None)
                .Where(s => !string.IsNullOrWhiteSpace(s))
                .Select(s => s.Split(","))
                .Select(x => new Buddy(x.FirstOrDefault()?.Trim(), x.LastOrDefault()?.Trim()))
                .ToList();
        }
    }
}