phase 2

Assets/Engine/Runtime/Measurements/Puzzle.cs

@@ -17,7 +17,8 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
 
         public float TotalTimeSpentOnPuzzle => Measurements.Sum(measurement => measurement.Time);
         public float AverageTimeToSolve => Measurements.Count > 0 ? TotalTimeSpentOnPuzzle / Measurements.Count : 0f;
-        
+        public NormalDistribution Distribution => new(TimesAsSamples());
+
         [UsedImplicitly]
         public Puzzle() {}
         public Puzzle(PuzzleModuleDescription puzzle)
@@ -25,6 +26,23 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
             ID = puzzle.Id;
         }
 
+        /// <summary>
+        /// Estimate how long a player in the given percentile will take to solve this puzzle.
+        /// </summary>
+        public float EstimateTimeToSolve(float percentile) => Distribution.InverseCumulative(percentile);
+
+        private float[] TimesAsSamples()
+        {
+            var samples = new float[Measurements.Count];
+            
+            for (var i = 0; i < Measurements.Count; i++)
+            {
+                samples[i] = Measurements[i].Time;
+            }
+
+            return samples;
+        }
+
         public override string ToString()
         {
             return $"{Engine.Theme.GetPuzzle(ID)}: avg. {AverageTimeToSolve.ToTimeSpan():m':'ss} ({string.Join(", ", Measurements)})";