补考、缓考成绩自动替换

src/Jiaowu.Api/Controllers/MakeupExamsController.cs

@@ -754,6 +754,27 @@ public sealed class MakeupExamsController(
         }
 
         var enrollmentByStudent = session.Enrollments.ToDictionary(e => e.StudentId);
+        var unresolvedStudentIds = scores
+            .Where(x => enrollmentByStudent.TryGetValue(x.StudentId, out var enrollment) &&
+                        !enrollment.SourceGradeRecordId.HasValue)
+            .Select(x => x.StudentId)
+            .Distinct()
+            .ToArray();
+        var fallbackGradeRecordIds = unresolvedStudentIds.Length == 0
+            ? new Dictionary<Guid, Guid>()
+            : (await db.GradeRecords.AsNoTracking()
+                    .Where(x => x.GradeSheet!.TeachingTaskId == session.TeachingTaskId)
+                    .WhereIn(unresolvedStudentIds, x => x.StudentId)
+                    .OrderByDescending(x => x.UpdatedAt)
+                    .Select(x => new { x.StudentId, x.Id })
+                    .ToListAsync(cancellationToken))
+                .GroupBy(x => x.StudentId)
+                .ToDictionary(x => x.Key, x => x.First().Id);
+        var missingReplacementTargets = unresolvedStudentIds
+            .Where(studentId => !fallbackGradeRecordIds.ContainsKey(studentId))
+            .ToArray();
+        if (missingReplacementTargets.Length > 0)
+            return ConflictProblem("存在无法关联原课程成绩的补考考生，不能录入补考成绩。请先建立该教学班成绩单后重试。");
 
         foreach (var entry in scores)
         {
@@ -762,22 +783,54 @@ public sealed class MakeupExamsController(
 
             enrollment.MakeupScore = entry.Score;
 
+            // Backfill legacy deferred-exam enrollments created before they
+            // carried SourceGradeRecordId, then use the same replacement
+            // path as absent and failed candidates.
+            if (!enrollment.SourceGradeRecordId.HasValue &&
+                fallbackGradeRecordIds.TryGetValue(entry.StudentId, out var fallbackGradeRecordId))
+                enrollment.SourceGradeRecordId = fallbackGradeRecordId;
+
             // Update the grade record — 补考合格按60分记
             if (enrollment.SourceGradeRecordId.HasValue)
             {
                 var record = await db.GradeRecords
+                    .Include(x => x.GradeSheet)
+                        .ThenInclude(x => x!.Items)
+                    .Include(x => x.ItemScores)
                     .FirstOrDefaultAsync(x => x.Id == enrollment.SourceGradeRecordId.Value,
                         cancellationToken);
                 if (record is not null)
                 {
-                    record.ExamStatus = GradeExamStatus.Makeup;
-                    // Cap passing score at 60
-                    var cappedScore = entry.Score >= 60 ? 60m : entry.Score;
-                    record.TotalScore = cappedScore;
-                    record.GradePoint = GradeCalculator.CalculateGradePoint(cappedScore);
-                    record.Notes = entry.Score >= 60
-                        ? $"补考合格（原始{entry.Score}分，按60分记）"
-                        : $"补考不合格（{entry.Score}分）";
+                    if (enrollment.Reason == MakeupReason.DeferredApproved &&
+                        record.GradeSheet is not null)
+                    {
+                        // A deferred exam is a later sitting of the normal
+                        // final. Its score therefore combines with the
+                        // already-entered regular and component scores.
+                        record.ExamStatus = GradeExamStatus.Deferred;
+                        record.FinalScore = entry.Score;
+                        record.TotalScore = GradeCalculator.CalculateTotal(
+                            record.RegularScore,
+                            record.FinalScore,
+                            record.ItemScores.ToList(),
+                            record.GradeSheet.RegularWeight,
+                            record.GradeSheet.FinalWeight,
+                            record.GradeSheet.Items.ToList(),
+                            record.ExamStatus);
+                        record.GradePoint = GradeCalculator.CalculateGradePoint(record.TotalScore);
+                        record.Notes = $"缓考成绩（期末{entry.Score}分，已按正常权重计入平时分）";
+                    }
+                    else
+                    {
+                        record.ExamStatus = GradeExamStatus.Makeup;
+                        // Cap passing score at 60
+                        var cappedScore = entry.Score >= 60 ? 60m : entry.Score;
+                        record.TotalScore = cappedScore;
+                        record.GradePoint = GradeCalculator.CalculateGradePoint(cappedScore);
+                        record.Notes = entry.Score >= 60
+                            ? $"补考合格（原始{entry.Score}分，按60分记）"
+                            : $"补考不合格（{entry.Score}分）";
+                    }
                 }
             }
         }

src/Jiaowu.Api/Infrastructure/Exams/MakeupExamEligibilityService.cs

@@ -44,13 +44,33 @@ public sealed class MakeupExamEligibilityService(AppDbContext db)
             })
             .ToListAsync(cancellationToken);
 
+        // A deferred exam replaces the same course-grade record after the
+        // makeup score is entered. Keep that link at enrollment time instead
+        // of leaving deferred candidates without a score-replacement target.
+        var deferredStudentIds = deferredStudents.Select(x => x.StudentId).ToArray();
+        var deferredGradeRecordIds = deferredStudentIds.Length == 0
+            ? new Dictionary<Guid, Guid>()
+            : (await db.GradeRecords.AsNoTracking()
+                    .Where(x => x.GradeSheet!.TeachingTaskId == teachingTaskId)
+                    .WhereIn(deferredStudentIds, x => x.StudentId)
+                    .OrderByDescending(x => x.UpdatedAt)
+                    .Select(x => new { x.StudentId, x.Id })
+                    .ToListAsync(cancellationToken))
+                .GroupBy(x => x.StudentId)
+                .ToDictionary(x => x.Key, x => x.First().Id);
+
         foreach (var s in deferredStudents)
         {
             if (!results.ContainsKey(s.StudentId))
             {
+                var sourceGradeRecordId = deferredGradeRecordIds.TryGetValue(
+                    s.StudentId, out var gradeRecordId)
+                    ? gradeRecordId
+                    : (Guid?)null;
                 results[s.StudentId] = new EligibleStudent(
                     s.StudentId, s.StudentNumber, s.Name, s.ClassName,
-                    MakeupReason.DeferredApproved, null,
+                    MakeupReason.DeferredApproved,
+                    SourceGradeRecordId: sourceGradeRecordId,
                     SourceDeferredExamId: s.Id);
             }
         }

src/Jiaowu.Api/Infrastructure/Grades/GradeCalculator.cs

@@ -22,7 +22,7 @@ public static class GradeCalculator
         IReadOnlyCollection<GradeItem> items,
         GradeExamStatus examStatus)
     {
-        if (examStatus != GradeExamStatus.Normal && examStatus != GradeExamStatus.Makeup)
+        if (examStatus is not (GradeExamStatus.Normal or GradeExamStatus.Deferred or GradeExamStatus.Makeup))
             return null;
 
         if (regularWeight > 0 && !regularScore.HasValue)