namespace Day_02.Day_02
{
    internal class Day02
    {
        private static string inputPath = "Day 02/day-02-input.txt";

        private static int Win = 6, Draw = 3, Lost = 0, Rock = 1, Paper = 2, Scissors = 3;

        private static string OpponentRock = "A", OpponentPaper = "B", OpponentScissors = "C",
                                  PlayRock = "X", PlayPaper = "Y", PlayScissors = "Z",
                                PlayWin = "Z", PlayDraw = "Y", PlayLose = "X";

        private static Dictionary<string, int> PossibleScores;

        private static void BuildScoreDic()
        {
            if (PossibleScores == null)
            {
                PossibleScores = new Dictionary<string, int>
                {
                    // Rock combos
                    { OpponentRock + " " + PlayPaper, Paper + Win }, // win
                    { OpponentRock + " " + PlayRock, Rock + Draw }, // draw
                    { OpponentRock + " " + PlayScissors, Scissors + Lost }, // lose

                    // Paper
                    { OpponentPaper + " " + PlayScissors, Scissors + Win }, // win
                    { OpponentPaper + " " + PlayPaper, Paper + Draw }, // draw
                    { OpponentPaper + " " + PlayRock, Rock + Lost }, // lose

                    // Scissors
                    { OpponentScissors + " " + PlayRock, Rock + Win }, // win
                    { OpponentScissors + " " + PlayScissors, Scissors + Draw }, // draw
                    { OpponentScissors + " " + PlayPaper, Paper + Lost } // lose
                };
            }
        }

        private static void BuildWinDrawLoseTable()
        {
            if (PossibleScores == null)
            {
                PossibleScores = new Dictionary<string, int>
                {
                    // Rock combos
                    { OpponentRock + " " + PlayWin, Paper + Win }, // win
                    { OpponentRock + " " + PlayDraw, Rock + Draw }, // draw
                    { OpponentRock + " " + PlayLose, Scissors + Lost }, // lose

                    // Paper
                    { OpponentPaper + " " + PlayWin, Scissors + Win }, // win
                    { OpponentPaper + " " + PlayDraw, Paper + Draw }, // draw
                    { OpponentPaper + " " + PlayLose, Rock + Lost }, // lose

                    // Scissors
                    { OpponentScissors + " " + PlayWin, Rock + Win }, // win
                    { OpponentScissors + " " + PlayDraw, Scissors + Draw }, // draw
                    { OpponentScissors + " " + PlayLose, Paper + Lost } // lose
                };
            }
        }

        private static int GetScore(string input) => PossibleScores[input];

        internal static int GetPart1()
        {
            BuildScoreDic();
            return File.ReadAllLines(inputPath)
                .Select(GetScore)
                .Sum();
        }

        internal static int GetPart2()
        {
            BuildWinDrawLoseTable();
            return File.ReadAllLines(inputPath)
                .Select(GetScore)
                .Sum();
        }
    }
}