phase 2

Assets/Engine/Runtime/Measurements/Measure.cs

@@ -18,13 +18,20 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
         private static Dictionary<int, PuzzleMeasurement> _runningMeasurements;
         private static Session _currentSession;
 
-        public static float AverageTime(IEnumerable<PuzzleModuleDescription> puzzles) =>
-            puzzles.Sum(puzzle => PuzzleStorage.Instance.Load(puzzle).AverageTimeToSolve);
         public static float AverageTime(PuzzleModuleDescription puzzle) =>
             PuzzleStorage.Instance.Load(puzzle).AverageTimeToSolve;
+        public static float AverageTime(IEnumerable<PuzzleModuleDescription> puzzles) => puzzles.Sum(AverageTime);
         public static float AverageTime(Room room) =>
             room.puzzles.Sum(puzzle => AverageTime((PuzzleModuleDescription)puzzle.description));
 
+        public static float EstimateTime(PuzzleModuleDescription puzzle) =>
+            PuzzleStorage.Instance.Load(puzzle).EstimateTimeToSolve(SessionPercentile());
+        public static float EstimateTime(IEnumerable<PuzzleModuleDescription> puzzles) => puzzles.Sum(EstimateTime);
+        public static float EstimateTime(Room room) =>
+            room.puzzles.Sum(puzzle => EstimateTime((PuzzleModuleDescription)puzzle.description));
+
+        public static float SessionPercentile() => _currentSession?.MeanPercentile ?? 0.5f;
+
         public static void StartMeasuring(PuzzleModuleDescription puzzle)
         {
             _runningMeasurements[puzzle.Id] = new PuzzleMeasurement

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)})";

Assets/Engine/Runtime/Measurements/PuzzleStorage.cs

@@ -8,6 +8,8 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
 {
     public class PuzzleStorage : MonoBehaviour
     {
+        private const int SchemaVersion = 1;
+        
         public static PuzzleStorage Instance { get; private set; }
 
         [SerializeField]
@@ -17,7 +19,20 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
 
         private void OnEnable()
         {
-            _realm = Realm.GetInstance(databasePath);
+            var config = new RealmConfiguration
+            {
+                SchemaVersion = SchemaVersion,
+                MigrationCallback = (migration, oldSchemaVersion) =>
+                {
+                    if (oldSchemaVersion < 1)
+                    {
+                        // migration from version 0 to 1
+                    }
+                    
+                    Logger.Log($"Migrated database to version {SchemaVersion}", LogType.Measuring);
+                }
+            };
+            _realm = Realm.GetInstance(config.ConfigWithPath(databasePath));
         }
 
         private void Awake()
@@ -41,10 +56,7 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
         {
             session.Time = time;
             
-            _realm.Write(() =>
-            {
-                _realm.Add(session);
-            });
+            _realm.Write(() => _realm.Add(session));
         }
 
         #endregion
@@ -84,6 +96,9 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
                 
                 // add solved puzzle to session
                 session.PuzzlesSolved.Add(found);
+                
+                // add time percentile to session
+                session.Percentiles.Add(found.Distribution.Cumulative(measurement.Time));
             });
         }
 

Assets/Engine/Runtime/Measurements/Session.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 using EscapeRoomEngine.Engine.Runtime.Utilities;
 using JetBrains.Annotations;
 using MongoDB.Bson;
@@ -13,8 +14,11 @@ namespace EscapeRoomEngine.Engine.Runtime.Measurements
         [PrimaryKey]
         public ObjectId ID { get; set; }
         public float Time { get; set; }
+        public IList<float> Percentiles { get; }
         public IList<Puzzle> PuzzlesSolved { get; }
 
+        public float MeanPercentile => Percentiles.Count == 0 ? .5f : Probability.Mean(Percentiles.ToArray());
+
         [UsedImplicitly]
         public Session()
         {