ArrayManipulator

namespace ArrayManipulator
{
    using System;
    using System.Collections.Generic;
    using System.Linq;

    public class ArrayManipulator
    {
        public static void Main()
        {
            List<string> collection = Console.ReadLine()
                .Split(new[] { ' ', '\t', ',' }, StringSplitOptions.RemoveEmptyEntries)
                .ToList();

            string command = Console.ReadLine();

            while (command != "end")
            {
                string[] commandArguments = command.Split(new[] { ' ', ',' });

                switch (commandArguments[0])
                {
                    case "exchange":
                        ExecuteExchangeCommand(collection, commandArguments);
                        Console.WriteLine("[{0}]", string.Join(", ", collection));
                        break;
                    case "max":
                        ExecuteMaxCommand(collection, commandArguments);
                        break;
                    case "min":
                        ExecuteMinCommand(collection, commandArguments);
                        break;
                    case "first":
                        ExecuteFirstCommand(collection, commandArguments);
                        break;
                    case "last":
                        ExecuteLastCommand(collection, commandArguments);
                        break;
                }

                command = Console.ReadLine();
            }
        }

        private static void ExecuteLastCommand(List<string> collection, string[] commandArguments)
        {
            int count = int.Parse(commandArguments[1]);

            if (commandArguments[2] == "even")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                List<int> evenNumbers = new List<int>();
                foreach (var item in collectionToInt)
                {
                    if (item % 2 != 0)
                    {
                        evenNumbers.Remove(item);
                    }

                    if (item % 2 == 0)
                    {
                        evenNumbers.Add(item);
                    }
                }

                if (evenNumbers.Count > 0)
                {
                    Console.WriteLine(evenNumbers.Take(count).Min());
                }

                else
                {
                    Console.WriteLine("No matches");
                }
            }

            else if (commandArguments[2] == "odd")
            {
                var collectionToInt = collection.Select(int.Parse).Reverse().ToList();
                string oddCountInts = collectionToInt.Where(i => i % 2 != 0).Take(count).Select(i => i.ToString()).Aggregate((a, b) => b += String.IsNullOrEmpty(b) ? a : "," + a);
                Console.WriteLine($"[{oddCountInts}]");
            }
        }

        private static void ExecuteFirstCommand(List<string> collection, string[] commandArguments)
        {
            int count = int.Parse(commandArguments[1]);

            if (commandArguments[2] == "even")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                string evenCountInts = collectionToInt.Where(i => i % 2 == 0).Take(count).Select(i => i.ToString()).Aggregate((a, b) => b += String.IsNullOrEmpty(b) ? a : "," + a);
                Console.WriteLine(evenCountInts);
            }

            else if (commandArguments[2] == "odd")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                string oddCountInts = collectionToInt.Where(i => i % 2 != 0).Take(count).Select(i => i.ToString()).Aggregate((a, b) => b += String.IsNullOrEmpty(b) ? a : "," + a);
                Console.WriteLine(oddCountInts);
            }
        }

        private static void ExecuteMinCommand(List<string> collection, string[] commandArguments)
        {
            if (commandArguments[1] == "even")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                List<int> evenNumbers = new List<int>();
                foreach (var item in collectionToInt)
                {
                    if (item % 2 != 0)
                    {
                        evenNumbers.Remove(item);
                    }

                    if (item % 2 == 0)
                    {
                        evenNumbers.Add(item);
                    }
                }

                if (evenNumbers.Count > 0)
                {
                    Console.WriteLine(evenNumbers.Min());
                }

                else
                {
                    Console.WriteLine("No matches");
                }
            }

            else if (commandArguments[1] == "odd")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                var minOdd = collectionToInt.Where(x => x % 2 != 0).Min();

                Console.WriteLine(minOdd);
            }
        }

        private static void ExecuteMaxCommand(List<string> collection, string[] commandArguments)
        {
            if (commandArguments[1] == "even")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                var maxEven = collectionToInt.Where(x => x % 2 == 0).Max();

                Console.WriteLine(collectionToInt.IndexOf(maxEven));
            }

            else if (commandArguments[1] == "odd")
            {
                var collectionToInt = collection.Select(int.Parse).ToList();
                var maxOdd = collectionToInt.Where(x => x % 2 != 0).Max();

                Console.WriteLine(collectionToInt.IndexOf(maxOdd));
            }
        }

        private static void ExecuteExchangeCommand(List<string> collection, string[] commandArguments)
        {
            int index = int.Parse(commandArguments[1]);

            for (int i = 0; i < index; i++)
            {
                string firstElement = collection[0];
                collection.Remove(firstElement);
                collection.Add(firstElement);
            }
        }
    }
}