Files
tiku-backend.net/Tiku.Infrastructure/Learning/PracticeSessions/PracticeSessionService.cs

328 lines
16 KiB
C#

using System.Text.Json;
using Microsoft.EntityFrameworkCore;
using Npgsql;
using Tiku.Application.Learning;
using Tiku.Domain.Common;
using Tiku.Domain.Content;
using Tiku.Domain.Learning;
namespace Tiku.Infrastructure.Learning;
internal sealed class PracticeSessionService(LearningServiceDependencies dependencies)
: LearningActivityServiceBase(dependencies), IPracticeSessionService
{
public async Task<PracticeSessionItem> CreatePracticeSessionAsync(
LearningActor actor,
PracticeSessionCommand command,
CancellationToken cancellationToken = default)
{
var assembly = await BuildPracticeAssemblyAsync(actor.TenantId, command, cancellationToken);
var access = await ResolvePracticeAccessAsync(actor, assembly, cancellationToken);
var questionReferenceIds = await CollectQuestionReferenceIdsAsync(actor, assembly, cancellationToken);
if (questionReferenceIds.Count == 0)
throw new LearningValidationException("no_practice_questions",
"No published questions are available for this practice target.");
var containsPlatformQuestion = await questionBankPersistence.TenantQuestionReferences.AsNoTracking().AnyAsync(
reference =>
reference.TenantId == actor.TenantId &&
questionReferenceIds.Contains(reference.Id) &&
reference.Source == QuestionSource.Platform,
cancellationToken);
if (containsPlatformQuestion)
await publicQuestionAccessPolicy.EnsureCanStartAsync(actor.TenantId, cancellationToken);
var now = DateTimeOffset.UtcNow;
var sessionExpiry = assembly.DurationMinutes.HasValue
? now.AddMinutes(Math.Min(240, assembly.DurationMinutes.Value + 15))
: now.AddHours(2);
var session = new PracticeSession
{
TenantId = actor.TenantId,
UserId = actor.UserId,
Mode = assembly.Mode,
TargetType = assembly.TargetType,
TargetId = assembly.TargetId,
BlueprintId = assembly.BlueprintId,
CollectionId = assembly.CollectionId,
EntryId = assembly.EntryId,
ContentNodeId = assembly.ContentNodeId,
QuestionCount = questionReferenceIds.Count,
DurationMinutes = assembly.DurationMinutes,
TotalScore = assembly.TotalScore,
ExpiresAt = sessionExpiry,
AccessMode = access.AccessMode,
AccessEntitlementId = access.EntitlementId,
AccessClassAssignmentId = access.ClassAssignmentId,
ConsumedFreeQuota = 0,
AccessGrantVersion = access.Snapshot.GrantVersion,
StrongRevocationVersion = access.Snapshot.StrongRevocationVersion,
AuthorizationExpiresAt = sessionExpiry,
AccessSnapshot = JsonSerializer.SerializeToElement(new
{
strategy = "compiled_access_v1",
contentSliceId = access.ContentSliceId,
businessLineId = access.Snapshot.BusinessLineId,
regionAccessStrategy = access.Snapshot.RegionAccessStrategy,
targetRegionId = access.Snapshot.TargetRegionId,
grantVersion = access.Snapshot.GrantVersion,
contentVersion = access.Snapshot.ContentVersion,
strongRevocationVersion = access.Snapshot.StrongRevocationVersion,
requestedCount = assembly.QuestionLimit,
grantedCount = questionReferenceIds.Count
}),
Metadata = command.Metadata.ValueKind is JsonValueKind.Undefined
? JsonDefaults.Object()
: command.Metadata
};
learningPersistence.PracticeSessions.Add(session);
var selections = await LoadQuestionSelectionsAsync(
actor.TenantId,
questionReferenceIds,
cancellationToken);
foreach (var selection in selections)
if (!QuestionGrader.HasValidAuthoritativeAnswer(
selection.QuestionType,
selection.CorrectOptionIndex,
selection.CorrectOptionIndices,
selection.AnswerText))
throw new LearningValidationException(
"practice_question_grading_rule_invalid",
$"Question '{selection.QuestionId}' has no valid authoritative grading rule.");
var scorePerQuestion = session.TotalScore.HasValue && selections.Count > 0
? session.TotalScore.Value / selections.Count
: (decimal?)null;
learningPersistence.PracticeSessionQuestions.AddRange(selections.Select((selection, index) =>
new PracticeSessionQuestion
{
TenantId = actor.TenantId,
PracticeSessionId = session.Id,
QuestionReferenceId = selection.QuestionReferenceId,
QuestionOwnerTenantId = selection.QuestionOwnerTenantId,
QuestionId = selection.QuestionId,
QuestionVersionId = selection.QuestionVersionId,
Position = index,
Score = scorePerQuestion,
QuestionType = selection.QuestionType,
TypeLabelSnapshot = selection.TypeLabel,
DifficultySnapshot = selection.Difficulty,
TagsSnapshot = selection.Tags,
GradingRulesSnapshot = BuildGradingRules(selection),
SnapshotVersion = 1
}));
learningPersistence.PracticeAccessEvents.Add(new PracticeAccessEvent
{
TenantId = actor.TenantId,
UserId = actor.UserId,
PracticeSessionId = session.Id,
EventType = PracticeAccessEventType.SessionCreated,
AccessMode = access.AccessMode switch
{
PracticeAccessMode.Package => PracticeAccessEventMode.Package,
PracticeAccessMode.ClassAssignment => PracticeAccessEventMode.ClassAssignment,
PracticeAccessMode.Staff => PracticeAccessEventMode.Staff,
PracticeAccessMode.Svip => PracticeAccessEventMode.Svip,
_ => PracticeAccessEventMode.Free
},
RequestedCount = assembly.QuestionLimit,
GrantedCount = selections.Count,
ConsumedFreeQuota = 0,
EntitlementId = access.EntitlementId,
Metadata = session.AccessSnapshot
});
await unitOfWork.SaveChangesAsync(cancellationToken);
return ToItem(session);
}
public async Task<PracticeSessionDetailItem> GetPracticeSessionDetailAsync(
LearningActor actor,
PracticeSessionFilter filter,
CancellationToken cancellationToken = default)
{
var session = await GetPracticeSessionAsync(actor, filter.PracticeSessionId, cancellationToken);
await learningAccessService.EnsureStrongRevocationVersionAsync(
actor, session.StrongRevocationVersion, cancellationToken);
var orderedQuestions = await LoadSessionQuestionItemsAsync(
actor.TenantId,
session.Id,
cancellationToken);
var answers = await learningPersistence.AnswerRecords
.AsNoTracking()
.Where(answer =>
answer.TenantId == actor.TenantId &&
answer.UserId == actor.UserId &&
answer.PracticeSessionId == session.Id &&
learningPersistence.CurrentAnswers.Any(current =>
current.TenantId == answer.TenantId && current.AnswerRecordId == answer.Id))
.ToArrayAsync(cancellationToken);
var answersByQuestion = answers
.GroupBy(answer => answer.SessionQuestionId)
.ToDictionary(
group => group.Key,
group => ToItem(
group.OrderByDescending(answer => answer.Revision).First()));
var revealAll = session.Status is PracticeSessionStatus.Submitted or PracticeSessionStatus.PendingReview;
var revealAnswered = !DefersSolutionUntilSubmission(session.Mode);
var revealQuestionIds = revealAll
? orderedQuestions.Select(item => item.SessionQuestionId).ToArray()
: revealAnswered ? answersByQuestion.Keys.ToArray() : [];
var solutions = revealQuestionIds.Length == 0
? new Dictionary<Guid, QuestionSolutionItem>()
: await LoadSolutionsAsync(actor.TenantId, session.Id, revealQuestionIds, cancellationToken);
return new PracticeSessionDetailItem(ToItem(session), orderedQuestions, answersByQuestion, solutions);
}
private async Task<Dictionary<Guid, QuestionSolutionItem>> LoadSolutionsAsync(
Guid tenantId,
Guid sessionId,
IReadOnlyCollection<Guid> revealQuestionIds,
CancellationToken cancellationToken)
{
var sessionQuestions = await learningPersistence.PracticeSessionQuestions.AsNoTracking()
.Where(item => item.TenantId == tenantId &&
item.PracticeSessionId == sessionId &&
revealQuestionIds.Contains(item.Id))
.ToArrayAsync(cancellationToken);
var versions = await LoadDeliveryVersionsAsync(tenantId, sessionQuestions, cancellationToken);
return sessionQuestions.ToDictionary(
item => item.Id,
item => ToSolutionItem(versions[item.QuestionVersionId]));
}
public async Task<PracticeSessionReportItem> SubmitPracticeSessionAsync(
LearningActor actor,
SubmitPracticeSessionCommand command,
CancellationToken cancellationToken = default)
{
if (string.IsNullOrWhiteSpace(command.IdempotencyKey))
throw new LearningValidationException("idempotency_key_required", "An idempotency key is required.");
await using var transaction = await unitOfWork.Database.BeginTransactionAsync(cancellationToken);
var session = await GetPracticeSessionAsync(actor, command.PracticeSessionId, cancellationToken);
await learningAccessService.EnsureStrongRevocationVersionAsync(
actor, session.StrongRevocationVersion, cancellationToken);
var requestHash = HashSubmission(command);
var existingOperation = await learningPersistence.LearningOperationIdempotencies.AsNoTracking().SingleOrDefaultAsync(
item =>
item.TenantId == actor.TenantId &&
item.UserId == actor.UserId &&
item.PracticeSessionId == session.Id &&
item.OperationType == "submit" &&
item.IdempotencyKey == command.IdempotencyKey, cancellationToken);
if (existingOperation is not null)
{
if (!string.Equals(existingOperation.RequestHash, requestHash, StringComparison.Ordinal))
{
SubmissionConflicts.Add(1);
throw new LearningValidationException("idempotency_conflict",
"The idempotency key was used with a different request.");
}
IdempotencyReplays.Add(1);
return existingOperation.ResponseSnapshot.Deserialize<PracticeSessionReportItem>()
?? throw new InvalidOperationException("The stored report response is invalid.");
}
if (session.Status != PracticeSessionStatus.Active)
throw new LearningValidationException("practice_session_not_active",
"Only an active practice session can be submitted.");
if (session.ExpiresAt.HasValue && session.ExpiresAt <= DateTimeOffset.UtcNow)
{
session.Status = PracticeSessionStatus.Expired;
session.Version++;
await unitOfWork.SaveChangesAsync(cancellationToken);
await transaction.CommitAsync(cancellationToken);
throw new LearningValidationException("practice_session_expired", "The practice session has expired.");
}
if (session.Version != command.ExpectedSessionVersion)
throw new LearningValidationException("practice_session_version_conflict",
"The practice session changed. Reload it before submitting.");
session.Status = PracticeSessionStatus.Scoring;
session.Version++;
var report = await BuildPracticeSessionReportAsync(actor, session, cancellationToken);
session.Status = report.IsFinal ? PracticeSessionStatus.Submitted : PracticeSessionStatus.PendingReview;
session.FinishedAt = report.SubmittedAt;
session.Version++;
var response = ToItem(report);
learningPersistence.LearningOperationIdempotencies.Add(new LearningOperationIdempotency
{
TenantId = actor.TenantId,
UserId = actor.UserId,
PracticeSessionId = session.Id,
OperationType = "submit",
IdempotencyKey = command.IdempotencyKey.Trim(),
RequestHash = requestHash,
ResponseSnapshot = JsonSerializer.SerializeToElement(response),
CompletedAt = report.SubmittedAt
});
try
{
await unitOfWork.SaveChangesAsync(cancellationToken);
await transaction.CommitAsync(cancellationToken);
}
catch (DbUpdateConcurrencyException)
{
SubmissionConflicts.Add(1);
throw new LearningValidationException("practice_session_version_conflict",
"The practice session changed during submission.");
}
catch (DbUpdateException exception) when (exception.InnerException is NpgsqlException)
{
SubmissionConflicts.Add(1);
throw new LearningValidationException("practice_submission_conflict",
"The practice session was already submitted by another request.");
}
return response;
}
private async Task<LearningResourceAccessDecision> ResolvePracticeAccessAsync(
LearningActor actor,
PracticeAssembly assembly,
CancellationToken cancellationToken)
{
if (assembly.BlueprintId.HasValue)
return await learningAccessService.EnsureResourceAccessAsync(
actor, LearningContentResourceType.Blueprint, assembly.BlueprintId.Value, cancellationToken);
if (assembly.CollectionId.HasValue)
return await learningAccessService.EnsureResourceAccessAsync(
actor, LearningContentResourceType.Collection, assembly.CollectionId.Value, cancellationToken);
if (assembly.ContentNodeId.HasValue)
return await learningAccessService.EnsureResourceAccessAsync(
actor, LearningContentResourceType.ContentNode, assembly.ContentNodeId.Value, cancellationToken);
if (assembly.EntryId.HasValue)
return await learningAccessService.EnsureResourceAccessAsync(
actor, LearningContentResourceType.ContentEntry, assembly.EntryId.Value, cancellationToken);
if (assembly.TargetId.HasValue &&
string.Equals(assembly.TargetType?.Replace("_", string.Empty), "questionbank",
StringComparison.OrdinalIgnoreCase))
return await learningAccessService.EnsureResourceAccessAsync(
actor, LearningContentResourceType.QuestionBank, assembly.TargetId.Value, cancellationToken);
var snapshot = await learningAccessService.GetSnapshotAsync(actor, cancellationToken);
if (snapshot.ContentSliceIds.Count == 0)
throw new LearningAccessException(
"learning_content_not_entitled",
"The current student has no active learning content grant.");
return new LearningResourceAccessDecision(
snapshot.ContentSliceIds.First(),
snapshot.ClassAssignmentIds.Count > 0
? PracticeAccessMode.ClassAssignment
: PracticeAccessMode.Package,
null,
snapshot.ClassAssignmentIds.FirstOrDefault() is { } assignmentId && assignmentId != Guid.Empty
? assignmentId
: null,
snapshot);
}
}