namespace AdventOfCode2023.Days.Ten
{
    internal class Day10Task1 : IRunnable
    {
        private HashSet<(int, int)> _visitedNodes = new HashSet<(int, int)>();

        public void Run()
        {
            //var inputLines = File.ReadAllLines("Days/Ten/Day10ExampleInput.txt");
            //var inputLines = File.ReadAllLines("Days/Ten/Day10ExampleInput2.txt");
            var inputLines = File.ReadAllLines("Days/Ten/Day10Input.txt");

            var map = new PipeMap(inputLines);
            _visitedNodes.Add((map.XCoord, map.YCoord));

            while (true)
            {
                bool haveMoved = false;
                for (int i = 0; i < 4; i++)
                {
                    if (map.CanMove((Direction)i))
                    {
                        map.Move((Direction)i);
                        if (_visitedNodes.Contains((map.XCoord, map.YCoord)))
                        {
                            map.Move(GetOppositeDirection((Direction)i));
                        }
                        else
                        {
                            _visitedNodes.Add((map.XCoord, map.YCoord));
                            haveMoved = true;
                        }
                    }
                }

                if (!haveMoved)
                {
                    break;
                }
            }

            Console.WriteLine("Nodes Visited: "+ _visitedNodes.Count);
            Console.WriteLine("Furthest Node: "+ _visitedNodes.Count/2);

        }




        public class PipeMap
        {
            public int XCoord { get; private set; }
            public int YCoord { get; private set; }
            public char CurrentPipe { get { return Map[YCoord][XCoord]; } }

            private string[] Map { get; set; }

            public PipeMap(string[] mapString)
            {
                Map = mapString;

                for (int y = 0; y < mapString.Length; y++)
                {
                    for (int x = 0; x < mapString[y].Length; x++)
                    {
                        if (mapString[y][x] == 'S')
                        {
                            YCoord = y;
                            XCoord = x;
                        }
                    }
                }
            }

            public void Move(Direction direction)
            {
                var adjacent = GetAdjacent(direction);

                XCoord = adjacent.Item1;
                YCoord = adjacent.Item2;
            }

            public bool CanMove(Direction direction)
            {
                bool currentPositionAllow = CanMoveFromCoord(direction, XCoord, YCoord);

                if (!currentPositionAllow) return false;

                var adjacent = GetAdjacent(direction);

                if (adjacent.Item3 != '.' && CanMoveFromCoord(GetOppositeDirection(direction), adjacent.Item1, adjacent.Item2))
                {
                    return true;
                }

                return false;
            }

            private bool CanMoveFromCoord(Direction direction, int xCoord, int yCoord)
            {
                switch (Map[yCoord][xCoord])
                {
                    case '|':
                        return direction == Direction.Up || direction == Direction.Down;
                    case '-':
                        return direction == Direction.Left || direction == Direction.Right;
                    case 'L':
                        return direction == Direction.Up || direction == Direction.Right;
                    case 'J':
                        return direction == Direction.Up || direction == Direction.Left;
                    case '7':
                        return direction == Direction.Left || direction == Direction.Down;
                    case 'F':
                        return direction == Direction.Right || direction == Direction.Down;
                    case 'S':
                        return true;
                    case '.':
                    default:
                        throw new Exception("you dun fucked up");
                }
            }

            private (int, int, char) GetAdjacent(Direction direction)
            {
                var newXCoord = XCoord;
                var newYCoord = YCoord;

                switch (direction)
                {
                    case Direction.Up:
                        newYCoord--;
                        break;
                    case Direction.Down:
                        newYCoord++;
                        break;
                    case Direction.Left:
                        newXCoord--;
                        break;
                    case Direction.Right:
                        newXCoord++;
                        break;
                }

                return (newXCoord, newYCoord, Map[newYCoord][newXCoord]);
            }
        }

        public enum Direction
        {
            Up, Right, Down, Left
        }

        public static Direction GetOppositeDirection(Direction direction)
        {
            switch (direction)
            {
                case Direction.Up:
                    return Direction.Down;
                case Direction.Down:
                    return Direction.Up;
                case Direction.Right:
                    return Direction.Left;
                case Direction.Left:
                    return Direction.Right;
                default: throw new Exception("You dun fucked up... again");
            }
        }
    }


}