using System;

namespace Clones
{
    public class CloneVersionSystem : ICloneVersionSystem
    {
        System.Collections.Generic.List<CloneNigga> cloneNigs = new System.Collections.Generic.List<CloneNigga> { new CloneNigga() };

        public string Execute(string nigga)
        {
            nigga = ':' + nigga;
            if (nigga.Contains(":learn"))
            {
                string[] crutch = nigga.Split(' ');
                var crutch2 = int.Parse(crutch[1]) - 1;
                cloneNigs[crutch2].programKnown.next = new Deck<int>(int.Parse(crutch[2]), cloneNigs[crutch2].programKnown, true);
                cloneNigs[crutch2].programKnown = cloneNigs[crutch2].programKnown.next;
            }
            if (nigga.Contains(":rollback"))
            {
                string[] crutch = nigga.Split(' ');
                var crutch2 = int.Parse(crutch[1]) - 1;
                if (cloneNigs[crutch2].programKnown.previous != null)
                {
                    //if (!cloneNigs[crutch2].cloned)
                    cloneNigs[crutch2].programKnown = cloneNigs[crutch2].programKnown.previous;
                    //else
                    //{
                    //    cloneNigs[crutch2].programKnown = new Deck<int> { Value = cloneNigs[crutch2].programKnown.previous.Value, next = cloneNigs[crutch2].programKnown };
                    //}
                }
            }
            if (nigga.Contains(":relearn"))
            {
                string[] crutch = nigga.Split(' ');
                var crutch2 = int.Parse(crutch[1]) - 1;
                cloneNigs[crutch2].programKnown = cloneNigs[crutch2].programKnown.next;
            }
            if (nigga.Contains(":clone"))
            {
                string[] crutch = nigga.Split(' ');
                var crutch2 = int.Parse(crutch[1]) - 1; ;
                cloneNigs.Add(cloneNigs[crutch2].Clone());
            }
            if (nigga.Contains(":check"))
            {
                string[] crutch = nigga.Split(' ');
                var crutch2 = int.Parse(crutch[1]) - 1;
                if (cloneNigs[crutch2].programKnown.previous != null)
                {
                    return cloneNigs[crutch2].programKnown.Value.ToString();
                }
                else
                {
                    return "basic";
                }
            }
            return null;
        }
    }

    public class CloneNigga
    {
        public Deck<int> programKnown = new Deck<int>();
        public bool cloned = false;

        public CloneNigga Clone()
        {
            return new CloneNigga { programKnown = Deck<int>.CopyDeck(this.programKnown), cloned = true };
        }
    }

    public class Deck<T>
    {
        public Deck<T> previous = null;
        public Deck<T> next = null;

        public T Value
        {
            get; set;
        }

        public Deck()
        {
            this.Value = default(T);
        }

        public Deck(T value)
        {
            this.Value = value;
        }

        public Deck(T value, Deck<T> nigga, bool what = true)
        {
            this.Value = value;
            if (what)
                previous = nigga;
            else
                next = nigga;
        }

        public static Deck<T> CopyDeck(Deck<T> nigga)
        {
            //if (nigga == null)
            //    return nigga;
            //Deck<T> flask = new Deck<T>(nigga.Value);
            //switch (marker)
            //{
            //    case 0:
            //        flask.next = CopyDeck(nigga.next, 1);
            //        flask.previous = CopyDeck(nigga.previous, -1);
            //        if (flask.next != null)
            //            flask.next.previous = flask;
            //        if (flask.previous != null)
            //            flask.previous.next = flask;
            //        break;
            //    case 1:
            //        flask.next = CopyDeck(nigga.next, 1);
            //        if(flask.next != null)
            //            flask.next.previous = flask;
            //        break;
            //    case -1:
            //        flask.previous = CopyDeck(nigga.previous, -1);
            //        if (flask.previous != null)
            //            flask.previous.next = flask;
            //        break;
            //}
            //return flask;

            if (nigga == new Deck<T>())
                return nigga;
            Deck<T> flask = new Deck<T>(nigga.Value);
            var crutch = nigga.previous;
            var crutch2 = new Deck<T>();
            if (crutch != null)
            {
                crutch2 = flask.previous = new Deck<T>();
                crutch2.next = flask;
            }
            while (crutch != null)
            {
                crutch2.Value = crutch.Value;
                crutch2.previous = new Deck<T>();
                crutch2.previous.next = crutch2;
                crutch2 = crutch2.previous;
                crutch = crutch.previous;
            }
            crutch = nigga.next;
            if (crutch != null)
            {
                crutch2 = flask.next = new Deck<T>();
                crutch2.previous = flask;
            }
            while (crutch != null)
            {
                crutch2.Value = crutch.Value;
                crutch2.next = new Deck<T>();
                crutch2.next.previous = crutch2;
                crutch2 = crutch2.next;
                crutch = crutch.next;
            }
            return flask;
        }
    }
}