Scale unique answer tracking

api/QuestionsApi/Models/AnswerStatistics.cs

@@ -0,0 +1,49 @@
+using MongoDB.Bson.Serialization.Attributes;
+
+namespace QuestionsApi.Models;
+
+public sealed class QuestionAttemptCounter
+{
+    public string QuestionExternalId { get; set; } = "";
+    public int Bucket { get; set; }
+    public string ChoiceId { get; set; } = "";
+    public long Count { get; set; }
+    public DateTime UpdatedUtc { get; set; } = DateTime.UtcNow;
+}
+
+public sealed class QuestionAttemptCounterTotal
+{
+    [BsonId]
+    public QuestionChoiceCounterKey Key { get; set; } = new();
+    public long Count { get; set; }
+}
+
+public sealed class QuestionAttemptCounterAggregate
+{
+    [BsonId]
+    public QuestionChoiceBucketKey Key { get; set; } = new();
+    public long Count { get; set; }
+}
+
+public sealed class QuestionChoiceBucketKey
+{
+    public string QuestionExternalId { get; set; } = "";
+    public int Bucket { get; set; }
+    public string ChoiceId { get; set; } = "";
+}
+
+public sealed class QuestionChoiceCounterKey
+{
+    public string QuestionExternalId { get; set; } = "";
+    public string ChoiceId { get; set; } = "";
+}
+
+public sealed class AnswerStatisticsState
+{
+    [BsonId]
+    public string Id { get; set; } = "answer-statistics-v1";
+    public bool Completed { get; set; }
+    public string LeaseOwner { get; set; } = "";
+    public DateTime LeaseUntilUtc { get; set; }
+    public DateTime UpdatedUtc { get; set; } = DateTime.UtcNow;
+}

api/QuestionsApi/Models/QuestionAttempt.cs

@@ -14,5 +14,15 @@ public class QuestionAttempt
     public string ChoiceId { get; set; } = "";
     public bool IsCorrect { get; set; }
     public bool IsSkip { get; set; }
+    public int CounterBucket { get; set; }
+    public bool? RatingApplied { get; set; }
+    public string RatingLeaseOwner { get; set; } = "";
+    public DateTime RatingLeaseUntilUtc { get; set; }
     public DateTime CreatedUtc { get; set; } = DateTime.UtcNow;
 }
+
+public sealed class QuestionAttemptRecordResult
+{
+    public bool Inserted { get; set; }
+    public QuestionAttempt Attempt { get; set; } = new();
+}