Add graphical duodenal ulcer interview

api/QuestionsApi/Dockerfile

@@ -9,6 +9,7 @@ RUN dotnet restore "api/QuestionsApi/QuestionsApi.csproj"
 
 COPY api/QuestionsApi/ api/QuestionsApi/
 COPY content/dynamic_questions/ content/dynamic_questions/
+COPY content/ccs/ content/ccs/
 WORKDIR /src/api/QuestionsApi
 RUN dotnet publish "QuestionsApi.csproj" -c Release -o /app/publish /p:UseAppHost=false /p:SourceRevisionId=${BUILD_REVISION}
 
@@ -17,6 +18,7 @@ ARG BUILD_REVISION
 WORKDIR /app
 COPY --from=build /app/publish .
 COPY --from=build /src/content/dynamic_questions ./content/dynamic_questions
+COPY --from=build /src/content/ccs ./content/ccs
 
 ENV ASPNETCORE_URLS=http://+:5008 \
     ASPNETCORE_ENVIRONMENT=Production \

api/QuestionsApi/Models/CcsModels.cs

@@ -64,6 +64,8 @@ public class CcsCaseRevision
     public int RealTimeMinutes { get; set; } = 20;
     public int Difficulty { get; set; } = 2;
     public List<string> Tags { get; set; } = [];
+    public string ExperienceMode { get; set; } = CcsExperienceModes.Management;
+    public CcsGraphicalPresentation GraphicalPresentation { get; set; } = new();
     public CcsInitialChart InitialChart { get; set; } = new();
     public CcsInitialInterview InitialInterview { get; set; } = new();
     public List<string> AllowedLocations { get; set; } = [];
@@ -79,6 +81,39 @@ public class CcsInitialInterview
 {
     public string StartNodeId { get; set; } = "";
     public List<CcsDialogueNode> Nodes { get; set; } = [];
+    public string OpeningPatientText { get; set; } = "";
+    public List<CcsInterviewTopic> Topics { get; set; } = [];
+    public string FinishChoiceText { get; set; } = "Finish the interview";
+    public string ClosingPatientText { get; set; } = "Thank you, doctor.";
+    public CcsInterviewDebrief Debrief { get; set; } = new();
+}
+
+public class CcsInterviewTopic
+{
+    public string Id { get; set; } = "";
+    public string ClinicianText { get; set; } = "";
+    public string PatientText { get; set; } = "";
+    public bool Required { get; set; }
+    public List<string> PrerequisiteTopicIds { get; set; } = [];
+}
+
+public class CcsInterviewDebrief
+{
+    public string LikelyDiagnosis { get; set; } = "";
+    public string Summary { get; set; } = "";
+    public List<string> TeachingPoints { get; set; } = [];
+}
+
+public class CcsGraphicalPresentation
+{
+    public string SceneKey { get; set; } = "";
+    public string PatientAssetKey { get; set; } = "";
+}
+
+public static class CcsExperienceModes
+{
+    public const string Management = "management";
+    public const string GraphicalInterview = "graphical_interview";
 }
 
 public class CcsDialogueNode
@@ -270,6 +305,7 @@ public class CcsImportResponse
 {
     public int OrdersUpserted { get; set; }
     public int CasesCreated { get; set; }
+    public int CasesSkipped { get; set; }
     public List<string> Errors { get; set; } = [];
 }
 
@@ -312,6 +348,9 @@ public class CcsCaseSummary
     public int Difficulty { get; set; }
     public List<string> Tags { get; set; } = [];
     public bool InteractiveInterviewAvailable { get; set; }
+    public bool GraphicalPresentationAvailable { get; set; }
+    public string ExperienceMode { get; set; } = CcsExperienceModes.Management;
+    public CcsGraphicalPresentation GraphicalPresentation { get; set; } = new();
 }
 
 public class CcsAttemptResponse
@@ -332,6 +371,8 @@ public class CcsAttemptResponse
     public DateTime CreatedUtc { get; set; }
     public int RealTimeMinutes { get; set; }
     public int ElapsedSeconds { get; set; }
+    public string ExperienceMode { get; set; } = CcsExperienceModes.Management;
+    public CcsGraphicalPresentation GraphicalPresentation { get; set; } = new();
     public string PatientSummary { get; set; } = "";
     public string ReasonForEncounter { get; set; } = "";
     public string Appearance { get; set; } = "";
@@ -346,6 +387,7 @@ public class CcsAttemptResponse
     public List<CcsExamDefinition> AvailableExams { get; set; } = [];
     public List<string> AllowedLocations { get; set; } = [];
     public CcsInterviewStateResponse? Interview { get; set; }
+    public CcsInterviewDebrief? InterviewDebrief { get; set; }
     public CcsCaseScore? Score { get; set; }
     public CcsRatingChange? Rating { get; set; }
     public List<QuestionReference> References { get; set; } = [];

api/QuestionsApi/Program.cs

@@ -29,6 +29,12 @@ if (args.FirstOrDefault() == "promote-dynamic-questions")
     return;
 }
 
+if (args.FirstOrDefault() == "promote-ccs-cases")
+{
+    Environment.ExitCode = await CcsPromotionCommand.RunAsync(args.Skip(1).ToArray(), Console.Out);
+    return;
+}
+
 if (args.FirstOrDefault() == "export-dynamic-review")
 {
     Environment.ExitCode = await DynamicReviewExportCommand.RunAsync(args.Skip(1).ToArray(), Console.Out);

api/QuestionsApi/Services/CcsCaseValidator.cs

@@ -34,6 +34,12 @@ public static class CcsCaseValidator
             if (string.IsNullOrWhiteSpace(item.PresentingLocation)) errors.Add(prefix + "presentingLocation required");
             if (item.RealTimeMinutes is not (10 or 20)) errors.Add(prefix + "realTimeMinutes must be 10 or 20");
             if (item.Difficulty is < 1 or > 5) errors.Add(prefix + "difficulty must be between 1 and 5");
+            if (item.ExperienceMode is not (CcsExperienceModes.Management or CcsExperienceModes.GraphicalInterview))
+                errors.Add(prefix + "experienceMode is invalid");
+            if (item.ExperienceMode == CcsExperienceModes.GraphicalInterview
+                && (string.IsNullOrWhiteSpace(item.GraphicalPresentation.SceneKey)
+                    || string.IsNullOrWhiteSpace(item.GraphicalPresentation.PatientAssetKey)))
+                errors.Add(prefix + "graphical interviews require sceneKey and patientAssetKey");
             if (string.IsNullOrWhiteSpace(item.InitialChart.PatientSummary) || string.IsNullOrWhiteSpace(item.InitialChart.ReasonForEncounter))
                 errors.Add(prefix + "initial patient summary and reason are required");
             if (!item.AllowedLocations.Contains(item.PresentingLocation, StringComparer.OrdinalIgnoreCase))
@@ -73,6 +79,10 @@ public static class CcsCaseValidator
                     if (criterion.ActionType == "order" && !orderCodes.Contains(target)) errors.Add(prefix + $"criterion {criterion.Id} references unknown order {target}");
                     if (criterion.ActionType == "exam" && !examCodes.Contains(target, StringComparer.OrdinalIgnoreCase)) errors.Add(prefix + $"criterion {criterion.Id} references unknown exam {target}");
                     if (criterion.ActionType == "location" && !item.AllowedLocations.Contains(target, StringComparer.OrdinalIgnoreCase)) errors.Add(prefix + $"criterion {criterion.Id} references unknown location {target}");
+                    if (criterion.ActionType == "dialogue_choice"
+                        && !item.InitialInterview.Topics.Any(value => value.Id.Equals(target, StringComparison.OrdinalIgnoreCase))
+                        && !item.InitialInterview.Nodes.SelectMany(value => value.Choices).Any(value => value.Id.Equals(target, StringComparison.OrdinalIgnoreCase)))
+                        errors.Add(prefix + $"criterion {criterion.Id} references unknown dialogue choice {target}");
                 }
             }
         }
@@ -123,6 +133,55 @@ public static class CcsCaseValidator
 
     private static void ValidateInterview(CcsInitialInterview interview, string prefix, List<string> errors)
     {
+        if (interview.Topics.Count > 0)
+        {
+            if (interview.Nodes.Count > 0 || !string.IsNullOrWhiteSpace(interview.StartNodeId))
+                errors.Add(prefix + "initialInterview cannot combine topics with nodes");
+            if (string.IsNullOrWhiteSpace(interview.OpeningPatientText))
+                errors.Add(prefix + "topic interview requires openingPatientText");
+            if (string.IsNullOrWhiteSpace(interview.FinishChoiceText) || string.IsNullOrWhiteSpace(interview.ClosingPatientText))
+                errors.Add(prefix + "topic interview requires finishChoiceText and closingPatientText");
+            var topicIds = interview.Topics.Select(value => value.Id).ToList();
+            if (topicIds.Any(string.IsNullOrWhiteSpace)
+                || topicIds.Distinct(StringComparer.OrdinalIgnoreCase).Count() != topicIds.Count)
+                errors.Add(prefix + "interview topic ids must be present and unique");
+            if (topicIds.Contains("finish_interview", StringComparer.OrdinalIgnoreCase))
+                errors.Add(prefix + "finish_interview is a reserved interview topic id");
+            if (!interview.Topics.Any(value => value.Required))
+                errors.Add(prefix + "topic interview requires at least one required topic");
+            foreach (var topic in interview.Topics)
+            {
+                if (string.IsNullOrWhiteSpace(topic.ClinicianText))
+                    errors.Add(prefix + $"interview topic {topic.Id} requires clinicianText");
+                if (string.IsNullOrWhiteSpace(topic.PatientText))
+                    errors.Add(prefix + $"interview topic {topic.Id} requires patientText");
+                foreach (var prerequisite in topic.PrerequisiteTopicIds)
+                    if (!topicIds.Contains(prerequisite, StringComparer.OrdinalIgnoreCase)
+                        || prerequisite.Equals(topic.Id, StringComparison.OrdinalIgnoreCase))
+                        errors.Add(prefix + $"interview topic {topic.Id} has an invalid prerequisite {prerequisite}");
+            }
+            var topicMap = interview.Topics.ToDictionary(value => value.Id, StringComparer.OrdinalIgnoreCase);
+            var resolved = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+            var resolving = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+            bool ResolveTopic(string topicId)
+            {
+                if (resolving.Contains(topicId))
+                {
+                    errors.Add(prefix + "interview topic prerequisites cannot contain cycles");
+                    return false;
+                }
+                if (resolved.Contains(topicId)) return true;
+                resolving.Add(topicId);
+                if (topicMap.TryGetValue(topicId, out var topic))
+                    foreach (var prerequisite in topic.PrerequisiteTopicIds.Where(topicMap.ContainsKey))
+                        ResolveTopic(prerequisite);
+                resolving.Remove(topicId);
+                resolved.Add(topicId);
+                return true;
+            }
+            foreach (var topic in interview.Topics) ResolveTopic(topic.Id);
+            return;
+        }
         if (string.IsNullOrWhiteSpace(interview.StartNodeId) && interview.Nodes.Count == 0) return;
         if (string.IsNullOrWhiteSpace(interview.StartNodeId)) errors.Add(prefix + "initialInterview.startNodeId required");
         if (interview.Nodes.Count == 0) { errors.Add(prefix + "initialInterview.nodes required"); return; }

api/QuestionsApi/Services/CcsPromotionCommand.cs

@@ -0,0 +1,92 @@
+using Microsoft.Extensions.Configuration;
+using MongoDB.Driver;
+using QuestionsApi.Models;
+using System.Text.Json;
+
+namespace QuestionsApi.Services;
+
+public static class CcsPromotionCommand
+{
+    public static async Task<int> RunAsync(string[] args, TextWriter output)
+    {
+        var apply = args.Contains("--apply", StringComparer.OrdinalIgnoreCase);
+        var sourceIndex = Array.FindIndex(args, value => value.Equals("--source", StringComparison.OrdinalIgnoreCase));
+        var source = sourceIndex >= 0 && sourceIndex + 1 < args.Length
+            ? args[sourceIndex + 1]
+            : Path.Combine(AppContext.BaseDirectory, "content", "ccs");
+        var files = File.Exists(source)
+            ? new[] { source }
+            : Directory.Exists(source)
+                ? Directory.EnumerateFiles(source, "*.json", SearchOption.AllDirectories).ToArray()
+                : [];
+        if (files.Length == 0)
+        {
+            await output.WriteLineAsync($"CCS content not found: {source}");
+            return 2;
+        }
+
+        var json = new JsonSerializerOptions(JsonSerializerDefaults.Web) { PropertyNameCaseInsensitive = true };
+        var request = new CcsImportRequest();
+        foreach (var file in files)
+        {
+            var parsed = JsonSerializer.Deserialize<CcsImportRequest>(await File.ReadAllTextAsync(file), json)
+                ?? throw new InvalidDataException($"Could not parse CCS content: {file}");
+            request.Orders.AddRange(parsed.Orders);
+            request.Cases.AddRange(parsed.Cases);
+        }
+        var duplicateOrders = request.Orders.GroupBy(value => value.Code, StringComparer.OrdinalIgnoreCase)
+            .Where(value => value.Count() > 1).Select(value => value.Key).ToList();
+        if (duplicateOrders.Count > 0)
+            throw new InvalidDataException($"Duplicate CCS order codes: {string.Join(", ", duplicateOrders)}");
+
+        var configuration = new ConfigurationBuilder().AddJsonFile("appsettings.json", optional: true)
+            .AddEnvironmentVariables().Build();
+        var mongo = new MongoDatabaseProvider(configuration);
+        var orders = mongo.Database.GetCollection<CcsOrderDefinition>("CcsOrderCatalog");
+        var cases = mongo.Database.GetCollection<CcsCaseRevision>("CcsCaseRevisions");
+        var existingCodes = (await orders.Find(Builders<CcsOrderDefinition>.Filter.Empty)
+            .Project(value => value.Code).ToListAsync()).ToHashSet(StringComparer.OrdinalIgnoreCase);
+        var errors = CcsCaseValidator.ValidateImport(request, existingCodes);
+        if (errors.Count > 0)
+        {
+            foreach (var error in errors) await output.WriteLineAsync(error);
+            return 1;
+        }
+        await output.WriteLineAsync($"Validated {request.Cases.Count} CCS case(s) and {request.Orders.Count} order(s).");
+        if (!apply)
+        {
+            await output.WriteLineAsync("Dry run only. Pass --apply to publish.");
+            return 0;
+        }
+
+        foreach (var order in request.Orders)
+        {
+            order.Code = order.Code.Trim().ToLowerInvariant();
+            order.UpdatedUtc = DateTime.UtcNow;
+            await orders.ReplaceOneAsync(value => value.Code == order.Code, order, new ReplaceOptions { IsUpsert = true });
+        }
+        var created = 0;
+        var unchanged = 0;
+        foreach (var incoming in request.Cases)
+        {
+            var current = await cases.Find(value => value.ExternalId == incoming.ExternalId && value.IsCurrent)
+                .SortByDescending(value => value.Version).FirstOrDefaultAsync();
+            if (current is not null && CcsStore.CaseContentDocument(current).Equals(CcsStore.CaseContentDocument(incoming)))
+            {
+                unchanged++;
+                continue;
+            }
+            if (current is not null)
+                await cases.UpdateOneAsync(value => value.Id == current.Id,
+                    Builders<CcsCaseRevision>.Update.Set(value => value.IsCurrent, false));
+            incoming.Id = null;
+            incoming.Version = (current?.Version ?? 0) + 1;
+            incoming.IsCurrent = true;
+            incoming.CreatedUtc = DateTime.UtcNow;
+            await cases.InsertOneAsync(incoming);
+            created++;
+        }
+        await output.WriteLineAsync($"Promotion complete: {created} created, {unchanged} unchanged.");
+        return 0;
+    }
+}

api/QuestionsApi/Services/CcsStore.cs

@@ -50,10 +50,16 @@ public sealed class CcsStore
             await _orders.ReplaceOneAsync(value => value.Code == order.Code, order, new ReplaceOptions { IsUpsert = true });
         }
         var created = 0;
+        var skipped = 0;
         foreach (var incoming in request.Cases)
         {
             var current = await _cases.Find(value => value.ExternalId == incoming.ExternalId && value.IsCurrent)
                 .SortByDescending(value => value.Version).FirstOrDefaultAsync();
+            if (current is not null && CaseContentDocument(current).Equals(CaseContentDocument(incoming)))
+            {
+                skipped++;
+                continue;
+            }
             if (current is not null)
                 await _cases.UpdateOneAsync(value => value.Id == current.Id, Builders<CcsCaseRevision>.Update.Set(value => value.IsCurrent, false));
             incoming.Id = null;
@@ -63,7 +69,17 @@ public sealed class CcsStore
             await _cases.InsertOneAsync(incoming);
             created++;
         }
-        return new CcsImportResponse { OrdersUpserted = request.Orders.Count, CasesCreated = created };
+        return new CcsImportResponse { OrdersUpserted = request.Orders.Count, CasesCreated = created, CasesSkipped = skipped };
+    }
+
+    internal static BsonDocument CaseContentDocument(CcsCaseRevision value)
+    {
+        var document = value.ToBsonDocument();
+        document.Remove("_id");
+        document.Remove(nameof(CcsCaseRevision.Version));
+        document.Remove(nameof(CcsCaseRevision.IsCurrent));
+        document.Remove(nameof(CcsCaseRevision.CreatedUtc));
+        return document;
     }
 
     public async Task<List<CcsCaseSummary>> ListCasesAsync() =>
@@ -109,6 +125,7 @@ public sealed class CcsStore
         if (definition is null) throw new KeyNotFoundException("CCS case not found.");
         var now = DateTime.UtcNow;
         var interview = EffectiveInterview(definition);
+        var interviewStartNodeId = definition.InitialInterview.Topics.Count > 0 ? "opening" : interview.StartNodeId;
         var attempt = new CcsAttempt
         {
             UserId = userId,
@@ -118,7 +135,7 @@ public sealed class CcsStore
             CaseVersion = definition.Version,
             Mode = CcsAttemptModes.Timed,
             OpeningCompleted = false,
-            InterviewNodeId = interview.StartNodeId,
+            InterviewNodeId = interviewStartNodeId,
             Location = definition.PresentingLocation,
             CurrentVitals = new Dictionary<string, string>(definition.InitialChart.Vitals),
             VitalHistory =
@@ -126,9 +143,11 @@ public sealed class CcsStore
                 new CcsVitalSnapshot { SimulatedMinute = 0, Values = new Dictionary<string, string>(definition.InitialChart.Vitals) }
             ],
             ActiveOrderCodes = definition.InitialChart.InitialOrderCodes.Distinct(StringComparer.OrdinalIgnoreCase).ToList(),
-            DeadlineUtc = now.AddMinutes(ActivePhaseMinutes(definition.RealTimeMinutes)),
-            HardDeadlineUtc = now.AddMinutes(definition.RealTimeMinutes),
-            RatingEligible = true,
+            DeadlineUtc = definition.ExperienceMode == CcsExperienceModes.GraphicalInterview
+                ? null : now.AddMinutes(ActivePhaseMinutes(definition.RealTimeMinutes)),
+            HardDeadlineUtc = definition.ExperienceMode == CcsExperienceModes.GraphicalInterview
+                ? null : now.AddMinutes(definition.RealTimeMinutes),
+            RatingEligible = definition.ExperienceMode != CcsExperienceModes.GraphicalInterview,
             Chart =
             [
                 new CcsChartEntry { Category = CcsChartCategories.Progress, Code = "reason_for_encounter", Title = "Reason for encounter", Text = definition.InitialChart.ReasonForEncounter },
@@ -416,9 +435,7 @@ public sealed class CcsStore
             ? attempt.VitalHistory
             : [new CcsVitalSnapshot { SimulatedMinute = attempt.SimulatedMinute, Values = new Dictionary<string, string>(attempt.CurrentVitals) }];
         CcsInterviewStateResponse? interview = null;
-        var interviewDefinition = EffectiveInterview(definition);
-        var currentInterviewNode = interviewDefinition.Nodes.FirstOrDefault(value =>
-            value.Id.Equals(attempt.InterviewNodeId, StringComparison.OrdinalIgnoreCase));
+        var currentInterviewNode = CurrentInterviewNode(attempt, definition);
         if (currentInterviewNode is not null)
         {
             interview = new CcsInterviewStateResponse
@@ -440,9 +457,13 @@ public sealed class CcsStore
             FinalOrdersDeadlineUtc = attempt.FinalOrdersDeadlineUtc,
             CreatedUtc = attempt.CreatedUtc, RealTimeMinutes = definition.RealTimeMinutes,
             ElapsedSeconds = Math.Max(0, (int)Math.Round(((attempt.CompletedUtc ?? DateTime.UtcNow) - attempt.CreatedUtc).TotalSeconds)),
+            ExperienceMode = definition.ExperienceMode, GraphicalPresentation = definition.GraphicalPresentation,
             PatientSummary = definition.InitialChart.PatientSummary, ReasonForEncounter = definition.InitialChart.ReasonForEncounter,
-            Appearance = definition.InitialChart.Appearance, History = definition.InitialChart.History,
-            HistorySections = definition.InitialChart.HistorySections,
+            Appearance = definition.InitialChart.Appearance,
+            History = definition.ExperienceMode == CcsExperienceModes.GraphicalInterview && !completed
+                ? "" : definition.InitialChart.History,
+            HistorySections = definition.ExperienceMode == CcsExperienceModes.GraphicalInterview && !completed
+                ? [] : definition.InitialChart.HistorySections,
             Vitals = attempt.CurrentVitals, Chart = attempt.Chart, ActiveOrderCodes = attempt.ActiveOrderCodes,
             ActiveOrders = activeOrders, VitalHistory = vitalHistory,
             PendingResults = attempt.PendingResults.Select(value => new CcsPendingResult
@@ -452,6 +473,8 @@ public sealed class CcsStore
             AvailableExams = attempt.State == CcsAttemptStates.Active ? definition.Exams : [],
             AllowedLocations = attempt.State == CcsAttemptStates.Active ? definition.AllowedLocations : [],
             Interview = interview,
+            InterviewDebrief = completed && definition.ExperienceMode == CcsExperienceModes.GraphicalInterview
+                ? definition.InitialInterview.Debrief : null,
             Score = completed ? attempt.Score : null, Rating = completed ? attempt.Rating : null,
             References = completed ? definition.References : []
         };
@@ -460,6 +483,11 @@ public sealed class CcsStore
     public static void ApplyDialogueChoice(CcsAttempt attempt, CcsCaseRevision definition, string choiceId, DateTime now)
     {
         if (attempt.OpeningCompleted == true) throw new InvalidOperationException("The initial interview is already complete.");
+        if (definition.InitialInterview.Topics.Count > 0)
+        {
+            ApplyTopicChoice(attempt, definition.InitialInterview, choiceId, now);
+            return;
+        }
         var interview = EffectiveInterview(definition);
         var node = interview.Nodes.FirstOrDefault(value =>
             value.Id.Equals(attempt.InterviewNodeId, StringComparison.OrdinalIgnoreCase))
@@ -730,9 +758,73 @@ public sealed class CcsStore
         ExternalId = value.ExternalId, Title = value.Title, System = value.System,
         PresentingLocation = value.PresentingLocation, RealTimeMinutes = value.RealTimeMinutes,
         Difficulty = value.Difficulty, Tags = value.Tags,
-        InteractiveInterviewAvailable = EffectiveInterview(value).Nodes.Count > 0
+        InteractiveInterviewAvailable = value.InitialInterview.Topics.Count > 0 || EffectiveInterview(value).Nodes.Count > 0,
+        GraphicalPresentationAvailable = !string.IsNullOrWhiteSpace(value.GraphicalPresentation.SceneKey)
+            && !string.IsNullOrWhiteSpace(value.GraphicalPresentation.PatientAssetKey),
+        ExperienceMode = value.ExperienceMode, GraphicalPresentation = value.GraphicalPresentation
     };
 
+    internal static CcsDialogueNode? CurrentInterviewNode(CcsAttempt attempt, CcsCaseRevision definition)
+    {
+        var topicInterview = definition.InitialInterview;
+        if (topicInterview.Topics.Count > 0)
+        {
+            if (attempt.InterviewNodeId.Equals("complete", StringComparison.OrdinalIgnoreCase))
+                return new CcsDialogueNode
+                {
+                    Id = "complete", PatientText = topicInterview.ClosingPatientText, IsTerminal = true
+                };
+            var patientText = attempt.InterviewNodeId.Equals("opening", StringComparison.OrdinalIgnoreCase)
+                ? topicInterview.OpeningPatientText
+                : topicInterview.Topics.FirstOrDefault(value =>
+                    value.Id.Equals(attempt.InterviewNodeId, StringComparison.OrdinalIgnoreCase))?.PatientText;
+            if (string.IsNullOrWhiteSpace(patientText)) return null;
+            var visited = attempt.InterviewChoiceIds.ToHashSet(StringComparer.OrdinalIgnoreCase);
+            var choices = topicInterview.Topics.Where(value => !visited.Contains(value.Id)
+                    && value.PrerequisiteTopicIds.All(visited.Contains))
+                .Select(value => new CcsDialogueChoice
+                {
+                    Id = value.Id, Text = value.ClinicianText, NextNodeId = value.Id
+                }).ToList();
+            if (topicInterview.Topics.Where(value => value.Required).All(value => visited.Contains(value.Id)))
+                choices.Add(new CcsDialogueChoice
+                {
+                    Id = "finish_interview", Text = topicInterview.FinishChoiceText, NextNodeId = "complete"
+                });
+            return new CcsDialogueNode
+            {
+                Id = attempt.InterviewNodeId, PatientText = patientText, Choices = choices
+            };
+        }
+        var interview = EffectiveInterview(definition);
+        return interview.Nodes.FirstOrDefault(value =>
+            value.Id.Equals(attempt.InterviewNodeId, StringComparison.OrdinalIgnoreCase));
+    }
+
+    private static void ApplyTopicChoice(CcsAttempt attempt, CcsInitialInterview interview, string choiceId, DateTime now)
+    {
+        if (choiceId.Equals("finish_interview", StringComparison.OrdinalIgnoreCase))
+        {
+            var visited = attempt.InterviewChoiceIds.ToHashSet(StringComparer.OrdinalIgnoreCase);
+            if (!interview.Topics.Where(value => value.Required).All(value => visited.Contains(value.Id)))
+                throw new ArgumentException("Complete the core interview topics before finishing.");
+            attempt.Actions.Add(Action("dialogue_choice", "finish_interview", attempt.SimulatedMinute, now));
+            attempt.InterviewChoiceIds.Add("finish_interview");
+            attempt.InterviewNodeId = "complete";
+            attempt.OpeningCompleted = true;
+            return;
+        }
+        var topic = interview.Topics.FirstOrDefault(value => value.Id.Equals(choiceId, StringComparison.OrdinalIgnoreCase))
+            ?? throw new ArgumentException("The dialogue choice is not available at the current interview node.");
+        if (attempt.InterviewChoiceIds.Contains(topic.Id, StringComparer.OrdinalIgnoreCase))
+            throw new ArgumentException("That interview topic has already been covered.");
+        if (!topic.PrerequisiteTopicIds.All(value => attempt.InterviewChoiceIds.Contains(value, StringComparer.OrdinalIgnoreCase)))
+            throw new ArgumentException("That interview topic is not available yet.");
+        attempt.Actions.Add(Action("dialogue_choice", topic.Id, attempt.SimulatedMinute, now));
+        attempt.InterviewChoiceIds.Add(topic.Id);
+        attempt.InterviewNodeId = topic.Id;
+    }
+
     internal static CcsInitialInterview EffectiveInterview(CcsCaseRevision definition)
     {
         if (!string.IsNullOrWhiteSpace(definition.InitialInterview.StartNodeId)