using System;
using System.Numerics;
using System.Text.RegularExpressions;

namespace Gameboard.ShogiUI.Sockets.Utilities
{
  public static class NotationHelper
  {
    private static readonly string BoardNotationRegex = @"(?<file>[a-iA-I])(?<rank>[1-9])";
    private static readonly char A = 'A';

    public static string ToBoardNotation(Vector2 vector)
    {
      return ToBoardNotation((int)vector.X, (int)vector.Y);
    }
    public static string ToBoardNotation(int x, int y)
    {
      var file = (char)(x + A);
      var rank = y + 1;
      return $"{file}{rank}";
    }

    public static Vector2 FromBoardNotation(string notation)
    {
      notation = notation.ToUpper();
      if (Regex.IsMatch(notation, BoardNotationRegex))
      {
        var match = Regex.Match(notation, BoardNotationRegex);
        char file = match.Groups["file"].Value[0];
        int rank = int.Parse(match.Groups["rank"].Value);
        return new Vector2(file - A, rank - 1);
      }
      throw new ArgumentException($"Board notation not recognized. Notation given: {notation}");
    }
  }
}