Inventory

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

namespace P03.Inventory
{
    internal class Program
    {
        static void Main(string[] args)
        {
            List<string> items = Console.ReadLine()
                .Split(", ", StringSplitOptions.RemoveEmptyEntries)
                .ToList();
            string command = Console.ReadLine();

            while (command != "Craft!")
            {
                string[] cmdArgs = command.Split(" - ");
                string action = cmdArgs[0];
                string item = cmdArgs[1];

                if (action == "Collect")
                {
                    if (!items.Contains(item))
                    {
                        items.Add(item);
                    }
                }
                else if (action == "Drop")
                {
                    if (items.Contains(item))
                    {
                        items.Remove(item);
                    }
                }
                else if (action == "Combine Items")
                {
                    string[] itemsToCombine = item.Split(":");
                    string olditem = cmdArgs[0];
                    string newItem = cmdArgs[1];

                    if (items.Contains(olditem))
                    {
                        items.Insert((items.IndexOf(olditem) + 1), newItem);
                    }
                }
                else if(action == "Renew")
                {
                    if(items.Contains(item))
                    {
                        items.Remove(item);
                        items.Add(item);
                    }
                }
                command = Console.ReadLine();
            }
            Console.WriteLine(String.Join(", ", items));
        }
    }
}