Rewrite the !dice command from scratch

Geekbot.net/Lib/DiceParser/SingleDie.cs

@@ -0,0 +1,72 @@
+using System.Collections.Generic;
+using Geekbot.net.Lib.Extensions;
+using Geekbot.net.Lib.RandomNumberGenerator;
+
+namespace Geekbot.net.Lib.DiceParser
+{
+    public class SingleDie
+    {
+        private readonly IRandomNumberGenerator _random;
+
+        public SingleDie(IRandomNumberGenerator random)
+        {
+            _random = random;
+        }
+
+        public int Sides { get; set; } = 20;
+        public int Amount { get; set; } = 1;
+        public DieAdvantageType AdvantageType { get; set; } = DieAdvantageType.None;
+
+        public string DiceName => AdvantageType switch
+        {
+            DieAdvantageType.Advantage => $"{Amount}d{Sides} (with advantage)",
+            DieAdvantageType.Disadvantage => $"{Amount}d{Sides} (with disadvantage)",
+            _ => $"{Amount}d{Sides}"
+        };
+
+        public List<DieResult> Roll()
+        {
+            var results = new List<DieResult>();
+
+            Amount.Times(() =>
+            {
+                var result = new DieResult
+                {
+                    Roll1 = _random.Next(1, Sides),
+                    AdvantageType = AdvantageType
+                };
+
+                if (AdvantageType == DieAdvantageType.Advantage || AdvantageType == DieAdvantageType.Disadvantage)
+                {
+                    result.Roll2 = _random.Next(1, Sides);
+                }
+
+                results.Add(result);
+            });
+
+            return results;
+        }
+
+        public void ValidateDie()
+        {
+            if (Amount < 1)
+            {
+                throw new DiceException("To few dice, must be a minimum of 1");
+            }
+            if (Amount > 24)
+            {
+                throw new DiceException("To many dice, maximum allowed is 24") { DiceName = DiceName };
+            }
+
+            if (Sides < 2)
+            {
+                throw new DiceException("Die must have at least 2 sides") { DiceName = DiceName };
+            }
+            
+            if (Sides > 144)
+            {
+                throw new DiceException("Die can not have more than 144 sides") { DiceName = DiceName };
+            }
+        }
+    }
+}