using System.Security.Cryptography;
using System.Text.RegularExpressions;

using Dungeoneer.Lexing;

namespace Dungeoneer {

	public class RollExpression {
		private IList<string> Parts;
		public string Print { get; private set; }
		public string Expression { get; private set; }
		public dynamic Result {
			get {
				try { return Scripting.Expr($"eval('{Expression}')"); }
				catch { return null; }
			}
		}

		public RollExpression(IList<string> parts) {
			this.Parts = parts;
			this.Print = "";
			this.Expression = "";

			//	build expression from string parts
			foreach(string piece in Parts) {
				//	die expression substitution
				var dieCheck = DiceToken.Match(piece);
				if(dieCheck.Success) {
					var token = new DiceToken(dieCheck);

					this.Print += $"{token.Format()} ";
					this.Expression += $"{token.Expression()} ";
				} else {
					var part = $"{piece} ";
					this.Expression += part;
					this.Print += part;
				}
			}
		}

	}

}