using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using static System.Console;

namespace _2018_05
{
    class Program
    {
        static void Main(string[] args)
        {
            int removes = 0;
            string resTab = File.ReadAllText(@"..\..\..\Data\Adventofcode_181205\2018_05_data.txt");
            //string resTab = "dabAcCaCBAcCcaDA";

            SortedSet<Char> charset = new SortedSet<char>();
            foreach (char x in resTab.ToCharArray())
            {
                try
                {
                    charset.Add(x);
                }
                catch (Exception)
                { }

            }

            foreach (char y in charset)
            {
                Write($"{y},");
            }

            ReadKey();

            string nextStr = StringReduce(ref removes, resTab);

            int winner = nextStr.Length;
            string wrkWin = "";
            foreach (char y in charset)
            {
                string wrk = "";
                wrk += y;
                if (wrk != wrk.ToLower())
                {
                    string tmpResTab = "";
                    string tmpResStr = "";
                    int tmpRemoves = 0;
                    foreach (char z in resTab.ToCharArray())
                    {
                        if (z.ToString() != wrk && z.ToString() != wrk.ToLower())
                        {
                            tmpResTab += z;
                        }
                    }
                    tmpResStr = StringReduce(ref tmpRemoves, tmpResTab);
                    if (tmpResStr.Length < winner)
                    {
                        nextStr = tmpResStr;
                        winner = tmpResStr.Length;
                        wrkWin = wrk + wrk.ToLower();
                    }
                }
            }

            WriteLine($"Resulterande sträng : {nextStr} , {nextStr.Length} tkn reducerad med {wrkWin}");
            ReadKey();

            nextStr = StringReduce(ref removes, resTab);

            WriteLine($"Resulterande sträng : {nextStr} , {nextStr.Length} tkn");
            ReadKey();

        }

        private static string StringReduce(ref int removes, string resTab)
        {
            int varv = 0;

            string nextStr = nextLevelStr(resTab, ref removes, ref varv);
            while (removes > 0)
            {
                nextStr = nextLevelStr(nextStr, ref removes, ref varv);
            }

            return nextStr;
        }

        private static string nextLevelStr(string resTab,ref int removes, ref int varv)
        {
            string tmp = "";
            removes = 0;
            //WriteLine($"inLängd: {resTab.Length}");
            foreach(char tkn in resTab.ToCharArray())
            {
                tmp += tkn;
                if (tmp.Length > 1)
                {
                    string v = tmp.Substring(tmp.Length - 2, 1);
                    string z = tmp.Substring(tmp.Length - 1, 1);

                    if ((v.ToUpper()== v && z.ToLower() == z || (z.ToUpper() == z && v.ToLower() == v))
                        && (v.ToUpper() == z.ToUpper()))
                    {
                        if (tmp.Length > 2)
                        {
                            tmp = tmp.Substring(0, tmp.Length - 2);
                            removes++;
                        }
                        else tmp = "";
                    }
                }
            }
            WriteLine($"varv {++varv} ; aktuell längd: {tmp.Length} removes = {removes}");
            return tmp;
        }
    }
}