This is Nick's attempt on the Math Game project.

MathGame.Dknx8888/Difficulty.cs

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+namespace MathGame.Dknx8888;
+
+public enum Difficulty
+{
+    Easy,
+    Medium,
+    Hard
+}

MathGame.Dknx8888/GameHistory.cs

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+using System.Text.Json;
+using static MathGame.Dknx8888.GameResultTemplate;
+
+namespace MathGame.Dknx8888;
+
+public class GameHistory
+{
+    private readonly JsonSerializerOptions _options = new() { WriteIndented = true };
+    public void ShowHistory()
+    {
+        while (true)
+        {
+            Console.Clear();
+
+        var filePath = GameHistoryJson.FilePath;
+        if (!File.Exists(filePath)) 
+        { 
+            EmptyHistoryError();
+            return;
+        } 
+
+        var json = File.ReadAllText(filePath);
+        if (string.IsNullOrWhiteSpace(json))
+        {
+            EmptyHistoryError();
+            return;
+        }
+
+        var gameResults = JsonSerializer.Deserialize<List<GameResult>>(json, _options) ?? [];
+        if (gameResults.Count == 0)
+        {
+            EmptyHistoryError();
+            return;
+        }
+
+        Console.WriteLine("Game History\n");
+        Console.WriteLine("Please select a game via ID (1,2, etc.) to show more details");
+        Console.WriteLine("Type q to go back\n");
+        Console.WriteLine($"{"ID",-4} | {"Date and Time Started",-22} | {"Score",-7} | {"Mode",-15} | {"Duration (sec)",-10}");
+        Console.WriteLine(new string('-', 76));
+
+        // Show from latest (bad idea?)
+        // gameResults.Reverse();
+        for (var i = 0; i < gameResults.Count; i++)
+        {
+            var (gameMode, _, score, duration, _, startTime) = gameResults[i];
+
+            Console.WriteLine($"{i + 1,-4} | {startTime,-22} | {score,-7} | {gameMode,-15} | {duration,-10:F2}");
+        }
+
+        int selectedId;
+        bool isValidId;
+
+        do
+        {
+            var input = Console.ReadLine()?.Trim();
+
+            // while loop in GameSession.cs does not work here because of this q
+            if (string.Equals(input, "q", StringComparison.OrdinalIgnoreCase))
+            {
+                return;
+            }
+
+            isValidId = int.TryParse(input, out selectedId)
+                        && selectedId >= 1
+                        && selectedId <= gameResults.Count;
+
+            if (!isValidId)
+            {
+                Console.WriteLine("Please enter a valid ID number, or q to go back");
+            }
+        } while (!isValidId);
+
+        var selectedGameResult = gameResults[selectedId - 1];
+        ShowDetails(selectedGameResult);
+        }
+    }
+
+    private static void EmptyHistoryError()
+    {
+        Console.WriteLine("No game history found.");
+        Console.WriteLine("Press any key to continue...");
+        Console.ReadKey();
+    }
+
+    private static void ShowDetails(GameResult selectedGameResult)
+    {
+        var (gameMode, difficulty, score, duration, questionResults, startTime) = selectedGameResult;
+
+        Console.Clear();
+        Console.WriteLine($"Start time: {startTime}");
+        Console.WriteLine($"Game mode: {gameMode}");
+        Console.WriteLine($"Difficulty: {difficulty}");
+        Console.WriteLine($"Duration (sec): {duration:F2}");
+        Console.WriteLine($"Score: {score}/5\n");
+
+        // Way better idea to include id in the records
+        var questionId = 1;
+        // Mind the one spaces
+        Console.WriteLine($"{"Q. Number", -10} {"Result", -8} {"Question", -12} {"Your Answer", 12} {"Correct Answer", 14}");
+        Console.WriteLine(new string('-', 62));
+
+        foreach (var questionResult in questionResults)
+        {
+            var (num1, num2, sign, playerAnswer, correctAnswer, isCorrect) = questionResult;
+            var correctDisplay = isCorrect ? "Right" : "Wrong";
+            var questionDisplay = $"{num1} {sign} {num2}";
+
+            Console.WriteLine($"{questionId, -10} {correctDisplay, -8} {questionDisplay, -12} {playerAnswer, 12} {correctAnswer, 14}");
+            ++questionId;
+        }
+        Console.WriteLine("Press any key to continue...");
+        Console.ReadKey();
+    }
+}

MathGame.Dknx8888/GameHistoryJson.cs

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+using System.Runtime.CompilerServices;
+
+namespace MathGame.Dknx8888;
+
+// Repository pattern in the future?
+public static class GameHistoryJson
+{
+    public static string FilePath => GetGameResultsFilePath();
+
+    // CallerFilePath gets the path of the source file that called this func
+    private static string GetGameResultsFilePath([CallerFilePath] string sourceFilePath = "")
+    {
+        var sourceDirectory = Path.GetDirectoryName(sourceFilePath)
+                              ?? throw new InvalidOperationException("Unable to determine the source file directory.");
+
+        return Path.Combine(sourceDirectory, "game-results.json");
+    }
+}

MathGame.Dknx8888/GameMode.cs

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+namespace MathGame.Dknx8888;
+
+public enum GameMode
+{
+    Addition,
+    Subtraction,
+    Multiplication,
+    Division,
+    Random
+}

MathGame.Dknx8888/GameResultTemplate.cs

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+namespace MathGame.Dknx8888;
+
+public static class GameResultTemplate
+{
+    public record QuestionResult (
+        int Num1,
+        int Num2,
+        char Sign,
+        double PlayerAnswer,
+        int CorrectAnswer,
+        bool IsCorrect
+        );
+
+    public record GameResult (
+        GameMode GameMode,
+        Difficulty Difficulty,
+        int Score,
+        double Duration,
+        List<QuestionResult> Questions,
+        DateTime StartTime
+    );
+}