Add functional simulation question review

api/QuestionsApi.Tests/ChoicePoolTests.cs

@@ -32,6 +32,18 @@ public sealed class ChoicePoolTests
         Assert.Equal("https://example.org/guideline", response.References[0].Url);
     }
 
+    [Fact]
+    public void ExamReviewContainsOnlyChoicesPresentedDuringTheExam()
+    {
+        var question = BuildQuestion(9);
+        var presented = new[] { "F", "A", "C", "H", "D" };
+        var response = QuestionResponse.FromModelWithChoices(question, presented);
+
+        Assert.Equal(presented, response.Choices.Select(choice => choice.Id));
+        Assert.Equal(presented.Order(), response.ChoiceExplanations.Keys.Order());
+        Assert.DoesNotContain("B", response.Choices.Select(choice => choice.Id));
+    }
+
     [Fact]
     public void PublishedQuestionRequiresCompletePerChoiceTeachingContent()
     {

api/QuestionsApi/Controllers/ExamSimulationsController.cs

@@ -40,6 +40,10 @@ public class ExamSimulationsController(ExamSimulationStore simulations) : Contro
         return simulation is null ? NoContent() : Ok(await simulations.ToResponseAsync(simulation));
     }
 
+    [HttpGet("completed")]
+    public async Task<IActionResult> Completed([FromQuery] int limit = 20, [FromQuery] DateTime? before = null) =>
+        Ok(await simulations.GetCompletedAsync(UserId(), limit, before));
+
     [HttpGet("{id}")]
     public async Task<IActionResult> Get(string id)
     {

api/QuestionsApi/Models/ExamSimulation.cs

@@ -119,6 +119,24 @@ public class ExamSimulationReadinessResponse
     public bool HasActiveSimulation { get; set; }
 }
 
+public class CompletedExamSimulationSummary
+{
+    public string Id { get; set; } = "";
+    public DateTime CompletedUtc { get; set; }
+    public int PredictedScore { get; set; }
+    public int RangeLow { get; set; }
+    public int RangeHigh { get; set; }
+    public int Correct { get; set; }
+    public int Total { get; set; }
+    public int SeenCount { get; set; }
+}
+
+public class CompletedExamSimulationPage
+{
+    public List<CompletedExamSimulationSummary> Items { get; set; } = [];
+    public DateTime? NextBefore { get; set; }
+}
+
 public class Step3Outcome
 {
     [BsonId]

api/QuestionsApi/Models/QuestionResponse.cs

@@ -62,6 +62,24 @@ public class QuestionResponse
         };
     }
 
+    public static QuestionResponse FromModelWithChoices(
+        Question question,
+        IReadOnlyCollection<string> presentedChoiceIds,
+        int questionElo = 1000)
+    {
+        var response = FromModel(question, questionElo: questionElo, includeChoicePool: true);
+        var ids = presentedChoiceIds.ToHashSet(StringComparer.Ordinal);
+        response.Choices = presentedChoiceIds
+            .Select(id => question.Choices.FirstOrDefault(choice => choice.Id == id))
+            .Where(choice => choice is not null)
+            .Cast<QuestionChoice>()
+            .ToList();
+        response.ChoiceExplanations = response.ChoiceExplanations.Where(entry => ids.Contains(entry.Key)).ToDictionary();
+        response.WrongAnswerFollowups = response.WrongAnswerFollowups.Where(entry => ids.Contains(entry.Key)).ToDictionary();
+        response.ChoiceSelectionPercentages = response.ChoiceSelectionPercentages.Where(entry => ids.Contains(entry.Key)).ToDictionary();
+        return response;
+    }
+
     private static List<QuestionChoice> SelectLegacyChoices(Question question)
     {
         if (question.Choices.Count <= 5)

api/QuestionsApi/Services/ExamSimulationStore.cs

@@ -33,6 +33,8 @@ public class ExamSimulationStore
         _metrics = metrics;
         _simulations.Indexes.CreateOne(new CreateIndexModel<ExamSimulation>(
             Builders<ExamSimulation>.IndexKeys.Ascending(item => item.UserId).Ascending(item => item.State)));
+        _simulations.Indexes.CreateOne(new CreateIndexModel<ExamSimulation>(
+            Builders<ExamSimulation>.IndexKeys.Ascending(item => item.UserId).Ascending(item => item.State).Descending(item => item.CompletedUtc)));
         _simulations.Indexes.CreateOne(new CreateIndexModel<ExamSimulation>(
             Builders<ExamSimulation>.IndexKeys.Ascending(item => item.UpdatedUtc)));
         _outcomes.Indexes.CreateOne(new CreateIndexModel<Step3Outcome>(
@@ -136,8 +138,8 @@ public class ExamSimulationStore
             Score = ExamSimulationScoring.Calculate(items, responseMap, questionMap),
             BlueprintTargets = targets,
             BlueprintActual = items.GroupBy(item => item.BlueprintCategory).ToDictionary(group => group.Key, group => group.Count()),
-            ReviewQuestions = items.Select(item => QuestionResponse.FromModel(
-                questionMap[item.QuestionExternalId], questionElo: item.QuestionElo, includeChoicePool: true)).ToList()
+            ReviewQuestions = items.Select(item => QuestionResponse.FromModelWithChoices(
+                questionMap[item.QuestionExternalId], item.PresentedChoiceIds, item.QuestionElo)).ToList()
         };
     }
 
@@ -154,6 +156,33 @@ public class ExamSimulationStore
         return simulation;
     }
 
+    public async Task<CompletedExamSimulationPage> GetCompletedAsync(string userId, int limit, DateTime? before)
+    {
+        limit = Math.Clamp(limit, 1, 50);
+        var filter = Builders<ExamSimulation>.Filter.Eq(item => item.UserId, userId) &
+            Builders<ExamSimulation>.Filter.Eq(item => item.State, ExamSimulationStates.Completed);
+        if (before is not null)
+            filter &= Builders<ExamSimulation>.Filter.Lt(item => item.CompletedUtc, before.Value);
+        var simulations = await _simulations.Find(filter).SortByDescending(item => item.CompletedUtc).Limit(limit + 1).ToListAsync();
+        var hasMore = simulations.Count > limit;
+        if (hasMore) simulations.RemoveAt(simulations.Count - 1);
+        return new CompletedExamSimulationPage
+        {
+            Items = simulations.Select(item => new CompletedExamSimulationSummary
+            {
+                Id = item.Id ?? "",
+                CompletedUtc = item.CompletedUtc ?? item.UpdatedUtc,
+                PredictedScore = item.Score?.PredictedScore ?? 0,
+                RangeLow = item.Score?.RangeLow ?? 0,
+                RangeHigh = item.Score?.RangeHigh ?? 0,
+                Correct = item.Score?.Correct ?? 0,
+                Total = item.Score?.Total ?? item.Items.Count,
+                SeenCount = item.Score?.SeenCount ?? 0
+            }).ToList(),
+            NextBefore = hasMore && simulations.Count > 0 ? simulations[^1].CompletedUtc : null
+        };
+    }
+
     public async Task<ExamSimulation> StartNextBlockAsync(ExamSimulation simulation)
     {
         if (simulation.State != ExamSimulationStates.BetweenBlocks)
@@ -244,7 +273,7 @@ public class ExamSimulationStore
         {
             response.ReviewQuestions = simulation.Items.OrderBy(item => item.BlockIndex).ThenBy(item => item.Position)
                 .Where(item => questionMap.ContainsKey(item.QuestionExternalId))
-                .Select(item => QuestionResponse.FromModel(questionMap[item.QuestionExternalId], questionElo: item.QuestionElo, includeChoicePool: true)).ToList();
+                .Select(item => QuestionResponse.FromModelWithChoices(questionMap[item.QuestionExternalId], item.PresentedChoiceIds, item.QuestionElo)).ToList();
         }
         return response;
     }