v2.0.0

校级管理员查看全校数据，学院管理员仅查看本学院数据。
待办按当前审批阶段统计，涵盖授课资格、成绩、调停课、学籍异动、教室借用等。
增加学期进度、教学任务发布、课表覆盖、成绩发布状态。
快捷入口根据管理员角色自动调整。
完善未配置学期、无待办、加载失败等状态。
适配桌面和 390px 移动端，无横向溢出。

.env.example

@@ -6,6 +6,9 @@ Database__Provider=MySql
 Database__ApplyMigrationsOnStartup=false
 Database__CommandTimeoutSeconds=30
 ConnectionStrings__MySql="Server=db.example.edu.cn;Port=3306;Database=jiaowu;User=APP_USER;Password=REPLACE_WITH_A_STRONG_PASSWORD;SslMode=VerifyFull;SslCa=/etc/jiaowu/mysql-ca.pem;"
+# 仅供备份与隔离恢复演练使用。该账号需要读取业务库，并仅能创建/删除
+# jiaowu_restore_drill_* 临时库；不要在此复用日常业务账号。
+# ConnectionStrings__OperationsMySql="Server=db.example.edu.cn;Port=3306;Database=jiaowu;User=OPS_USER;Password=REPLACE_WITH_A_STRONG_PASSWORD;SslMode=VerifyFull;SslCa=/etc/jiaowu/mysql-ca.pem;"
 # Redis 是可选加速器；留空时应用仅使用进程内缓存。
 # ConnectionStrings__Redis="redis.example.edu.cn:6380,user=jiaowu,password=REPLACE_WITH_A_STRONG_PASSWORD,ssl=true,abortConnect=false"
 
@@ -32,6 +35,16 @@ Cache__AnalyticsExpirationMinutes=3
 Cache__AnalyticsLocalExpirationSeconds=30
 Cache__MaximumPayloadKilobytes=2048
 
+# 运维控制台备份目录必须位于持久化、仅服务账号可写的位置。
+Operations__BackupDirectory=/var/lib/jiaowu/backups
+Operations__BackupWarningHours=24
+Operations__ToolTimeoutMinutes=30
+Operations__MySqlDumpPath=mysqldump
+Operations__MySqlClientPath=mysql
+# 按实际客户端补充 TLS 参数；Oracle MySQL 客户端示例：
+# Operations__MySqlAdditionalArguments__0=--ssl-mode=VERIFY_IDENTITY
+# Operations__MySqlAdditionalArguments__1=--ssl-ca=/etc/jiaowu/mysql-ca.pem
+
 Jwt__Issuer=Jiaowu.Api
 Jwt__Audience=Jiaowu.Web
 Jwt__Key=REPLACE_WITH_AT_LEAST_32_RANDOM_BYTES

Dockerfile

@@ -30,11 +30,14 @@ FROM mcr.microsoft.com/dotnet/aspnet:10.0-alpine AS final
 WORKDIR /app
 ENV ASPNETCORE_ENVIRONMENT=Production \
     ASPNETCORE_HTTP_PORTS=8080 \
-    DOTNET_EnableDiagnostics=0
+    DOTNET_EnableDiagnostics=0 \
+    Operations__BackupDirectory=/var/lib/jiaowu/backups \
+    Operations__MySqlDumpPath=mariadb-dump \
+    Operations__MySqlClientPath=mariadb
 EXPOSE 8080
 COPY --from=build /app/publish/ ./
 ARG UID=10001
-RUN apk add --no-cache font-noto-cjk
+RUN apk add --no-cache font-noto-cjk mariadb-client
 RUN adduser \
     --disabled-password \
     --gecos "" \
@@ -43,5 +46,9 @@ RUN adduser \
     --no-create-home \
     --uid "${UID}" \
     appuser
+RUN mkdir -p /var/lib/jiaowu/backups \
+    && chown appuser:appuser /var/lib/jiaowu/backups \
+    && chmod 700 /var/lib/jiaowu/backups
+VOLUME ["/var/lib/jiaowu/backups"]
 USER appuser
 ENTRYPOINT ["dotnet", "Jiaowu.Api.dll"]

README.md

@@ -101,6 +101,12 @@ sudo chown -R root:jiaowu /opt/jiaowu
 sudo chmod 0750 /opt/jiaowu
 sudo chmod 0750 /opt/jiaowu/Jiaowu.Api
 sudo chmod 0640 /opt/jiaowu/.env
+sudo install -d \
+  --owner=jiaowu \
+  --group=jiaowu \
+  --mode=0700 \
+  /var/lib/jiaowu/backups
+sudo apt-get install default-mysql-client
 ```
 
 如果账号已存在，`useradd` 会报错，可以跳过该命令。RHEL 系发行版的 `nologin` 通常
@@ -297,6 +303,25 @@ Outbox 租约恢复改为按维护周期执行，避免积压发布时每条消
 消息会根据 Outbox 状态和租约继续补投。迁移服务应先应用
 `BackgroundJobOutbox` 数据库迁移，再启动应用实例。
 
+### 运维与审计控制台
+
+超级管理员可从“组织与权限 → 运维与审计”查询写操作日志、三类失败后台任务、数据库、
+缓存与任务通道健康状态，并查看由 5xx、失败/重试任务、健康探针和备份时效汇总出的异常
+告警。查询接口和备份操作均在后端强制要求 `SuperAdmin`，不能只依赖前端菜单隐藏。
+
+SQLite 开发环境直接使用在线备份 API。MySQL 环境需要在服务器安装 `mysqldump` 与
+`mysql`（容器镜像已包含对应的 `mariadb-dump` 与 `mariadb` 客户端），并配置独立的
+`ConnectionStrings__OperationsMySql`。该账号不得复用日常业务账号：它需要读取业务库，
+并只应被授权创建和删除名称为 `jiaowu_restore_drill_*` 的临时演练库。恢复演练不会覆盖
+当前业务库，流程是“校验 SHA-256 → 恢复到随机临时库 → 检查表结构 → 删除临时库”。
+
+备份目录必须是仅服务账号可写的持久化目录。示例配置使用
+`/var/lib/jiaowu/backups`；Compose 已挂载独立命名卷。启用 MySQL TLS 时，还要通过
+`Operations__MySqlAdditionalArguments__N` 传入与所选命令行客户端匹配的 CA 与主机名
+校验参数。例如 Oracle MySQL 客户端使用 `--ssl-mode=VERIFY_IDENTITY` 和
+`--ssl-ca=/etc/jiaowu/mysql-ca.pem`，容器内 MariaDB 客户端使用 `--ssl`、
+`--ssl-ca=...` 与 `--ssl-verify-server-cert`。
+
 ## 跨平台发布与 Docker
 
 `.gitea/workflows/publish.yml` 只在推送 `v*` 标签或手动运行时执行，普通分支 push

compose.app.example.yml

@@ -17,11 +17,15 @@ services:
       options:
         max-size: "10m"
         max-file: "3"
+    volumes:
+      - jiaowu-backups:/var/lib/jiaowu/backups
 
     # 如果 .env 中的 SslCa=/etc/jiaowu/mysql-ca.pem，请把 CA 放到
-    # ./certs/mysql-ca.pem，并取消下面三行注释。
-    # volumes:
+    # ./certs/mysql-ca.pem，并在上面的 volumes 中追加以下四行。
     #   - type: bind
     #     source: ./certs/mysql-ca.pem
     #     target: /etc/jiaowu/mysql-ca.pem
     #     read_only: true
+
+volumes:
+  jiaowu-backups:

compose.example.yml

@@ -138,6 +138,8 @@ services:
       - "${JIAOWU_PORT:-8080}:8080"
     restart: unless-stopped
     init: true
+    volumes:
+      - backup-data:/var/lib/jiaowu/backups
     logging: *json-logging
 
   # 工具型一次性服务：普通 docker compose up 不会执行它。
@@ -161,3 +163,4 @@ services:
 volumes:
   mysql-data:
   rabbitmq-data:
+  backup-data:

src/Jiaowu.Api/Controllers/AcademicPlanningController.cs

@@ -0,0 +1,621 @@
+using System.ComponentModel.DataAnnotations;
+using Jiaowu.Api.Domain.Academic;
+using Jiaowu.Api.Domain.Identity;
+using Jiaowu.Api.Infrastructure.Auth;
+using Jiaowu.Api.Infrastructure.Graduation;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+
+namespace Jiaowu.Api.Controllers;
+
+[ApiController]
+[Authorize(Roles = SystemRoles.Student)]
+[Route("api/student/academic-planning")]
+public sealed class AcademicPlanningController(
+    AppDbContext db,
+    ICurrentUserDataScope currentUserDataScope) : ControllerBase
+{
+    [HttpGet]
+    public async Task<ActionResult> Get(CancellationToken cancellationToken)
+    {
+        var loaded = await LoadAsync(cancellationToken);
+        if (loaded.Error is not null) return loaded.Error;
+        var context = loaded.Context!;
+
+        var completion = CurriculumCompletionRules.Evaluate(
+            context.Plan.Modules,
+            context.PassedCourseIds);
+        var planCompletedCredits = context.Courses
+            .Where(x => context.PassedCourseIds.Contains(x.CourseId))
+            .Sum(x => x.Credits);
+        var suggestionIds = AcademicPlanningRules.SuggestNextSemester(
+            context.CourseSnapshots,
+            context.PassedCourseIds,
+            context.InProgressCourseIds,
+            context.NextSemester);
+        var suggestionIdSet = suggestionIds.ToHashSet();
+        var latestAudit = await db.GraduationAuditResults.AsNoTracking()
+            .Where(x =>
+                x.StudentId == context.Student.Id &&
+                x.GraduationAuditBatch!.Status ==
+                    GraduationAuditBatchStatus.Published)
+            .OrderByDescending(x => x.GraduationAuditBatch!.GraduationYear)
+            .ThenByDescending(x => x.GraduationAuditBatch!.PublishedAt)
+            .Select(x => new
+            {
+                BatchName = x.GraduationAuditBatch!.Name,
+                x.GraduationAuditBatch.GraduationYear,
+                x.RequiredCredits,
+                x.EarnedCredits,
+                x.RequiredCourseCount,
+                x.PassedRequiredCourseCount,
+                x.FailedCourseCount,
+                x.MissingCourseNames,
+                x.Conclusion,
+                x.IsOverridden,
+                x.ReviewComment,
+                x.GraduationAuditBatch.PublishedAt
+            })
+            .FirstOrDefaultAsync(cancellationToken);
+
+        var endSemester = Math.Max(
+            context.Plan.Major!.SchoolingYears * 2,
+            context.NextSemester + 3);
+        return Ok(new
+        {
+            Student = new
+            {
+                context.Student.Id,
+                context.Student.StudentNumber,
+                context.Student.Name,
+                context.Student.EnrollmentYear,
+                context.Student.Status,
+                ClassName = context.Student.AdministrativeClass!.Name,
+                MajorName = context.Student.AdministrativeClass.Major!.Name,
+                CollegeName =
+                    context.Student.AdministrativeClass.Major.College!.Name
+            },
+            Plan = new
+            {
+                context.Plan.Id,
+                context.Plan.Name,
+                context.Plan.Version,
+                context.Plan.TotalCredits,
+                SchoolingYears = context.Plan.Major.SchoolingYears,
+                CurrentSemester = context.CurrentSemester,
+                NextSemester = context.NextSemester,
+                StandardGraduationSemester =
+                    context.Plan.Major.SchoolingYears * 2
+            },
+            Baseline = new
+            {
+                EarnedCredits = context.EarnedCredits,
+                PlanCompletedCredits = planCompletedCredits,
+                CreditGap = Math.Max(
+                    context.Plan.TotalCredits - context.EarnedCredits,
+                    0),
+                CompletionRate = context.Plan.TotalCredits <= 0
+                    ? 0
+                    : Math.Min(100, Math.Round(
+                        planCompletedCredits / context.Plan.TotalCredits * 100,
+                        1)),
+                completion.RequirementCount,
+                completion.PassedRequirementCount,
+                completion.MissingRequirements,
+                InProgressCredits = context.Courses
+                    .Where(x => context.InProgressCourseIds.Contains(x.CourseId))
+                    .Sum(x => x.Credits)
+            },
+            Terms = Enumerable.Range(
+                    context.NextSemester,
+                    endSemester - context.NextSemester + 1)
+                .Select(semester => new
+                {
+                    Semester = semester,
+                    Label = FormatSemester(
+                        context.Student.EnrollmentYear,
+                        semester),
+                    IsBeyondStandard =
+                        semester > context.Plan.Major.SchoolingYears * 2
+                }),
+            Courses = context.Courses
+                .OrderBy(x => x.RecommendedSemester)
+                .ThenBy(x => x.CourseCode)
+                .Select(course => new
+                {
+                    course.CourseId,
+                    course.CourseCode,
+                    course.CourseName,
+                    course.Credits,
+                    course.RecommendedSemester,
+                    course.Type,
+                    course.ModuleCode,
+                    course.ModuleName,
+                    Status = context.StatusByCourse[course.CourseId],
+                    IsSuggested = suggestionIdSet.Contains(course.CourseId),
+                    Prerequisites = course.Prerequisites.Select(item => new
+                    {
+                        item.CourseId,
+                        item.CourseCode,
+                        item.CourseName,
+                        IsCompleted =
+                            context.PassedCourseIds.Contains(item.CourseId),
+                        IsInProgress =
+                            context.InProgressCourseIds.Contains(item.CourseId)
+                    })
+                }),
+            NextSemesterSuggestion = suggestionIds.Select(courseId =>
+            {
+                var course = context.CourseById[courseId];
+                return new
+                {
+                    course.CourseId,
+                    course.CourseCode,
+                    course.CourseName,
+                    course.Credits,
+                    course.Type,
+                    Reason = course.Type == CurriculumCourseType.Required &&
+                             course.RecommendedSemester <= context.NextSemester
+                        ? "计划学期已到，且先修条件已满足"
+                        : course.Type == CurriculumCourseType.Required
+                            ? "必修课程，按培养方案顺序推进"
+                            : "用于补足培养模块与总学分"
+                };
+            }),
+            LatestGraduationAudit = latestAudit,
+            Assumptions = new[]
+            {
+                "模拟课程按顺利通过计算，不会写入成绩或正式选课。",
+                $"预计毕业学期按每学期最多 {AcademicPlanningRules.RecommendedSemesterCreditLimit:0} 学分估算。",
+                "当前在读课程按本学期顺利完成计入预测。"
+            }
+        });
+    }
+
+    [HttpPost("simulate")]
+    public async Task<ActionResult> Simulate(
+        AcademicPlanningRequest request,
+        CancellationToken cancellationToken)
+    {
+        var loaded = await LoadAsync(cancellationToken);
+        if (loaded.Error is not null) return loaded.Error;
+        var context = loaded.Context!;
+
+        var selections = request.Terms
+            .SelectMany(term => term.CourseIds.Select(courseId => new
+            {
+                term.Semester,
+                CourseId = courseId
+            }))
+            .ToList();
+        var duplicate = selections
+            .GroupBy(x => x.CourseId)
+            .FirstOrDefault(group => group.Count() > 1);
+        if (duplicate is not null)
+            return ValidationProblem("同一门课程不能安排在多个学期。");
+        if (request.Terms.Any(x =>
+                x.Semester < context.NextSemester ||
+                x.Semester > context.NextSemester + 12))
+            return ValidationProblem("模拟学期超出了可规划范围。");
+
+        var invalidCourse = selections.FirstOrDefault(x =>
+            !context.CourseById.ContainsKey(x.CourseId));
+        if (invalidCourse is not null)
+            return ValidationProblem("模拟计划包含不属于当前培养方案的课程。");
+        var alreadyHandled = selections.FirstOrDefault(x =>
+            context.PassedCourseIds.Contains(x.CourseId) ||
+            context.InProgressCourseIds.Contains(x.CourseId));
+        if (alreadyHandled is not null)
+            return ValidationProblem("已完成或当前在读课程无需重复安排。");
+
+        var plannedSemesters = selections.ToDictionary(
+            x => x.CourseId,
+            x => x.Semester);
+        var projectedCourseIds = context.PassedCourseIds
+            .Concat(context.InProgressCourseIds)
+            .Concat(plannedSemesters.Keys)
+            .ToHashSet();
+        var completion = CurriculumCompletionRules.Evaluate(
+            context.Plan.Modules,
+            projectedCourseIds);
+        var addedCredits = context.Courses
+            .Where(x =>
+                !context.PassedCourseIds.Contains(x.CourseId) &&
+                (context.InProgressCourseIds.Contains(x.CourseId) ||
+                 plannedSemesters.ContainsKey(x.CourseId)))
+            .Sum(x => x.Credits);
+        var projectedEarnedCredits = context.EarnedCredits + addedCredits;
+        var creditGap = Math.Max(
+            context.Plan.TotalCredits - projectedEarnedCredits,
+            0);
+        var prerequisiteIssues = AcademicPlanningRules.FindPrerequisiteIssues(
+            context.CourseSnapshots,
+            context.PassedCourseIds,
+            context.InProgressCourseIds,
+            plannedSemesters);
+        var conflicts = prerequisiteIssues.Select(issue =>
+        {
+            var course = context.CourseById[issue.CourseId];
+            var prerequisite = context.AllCourseLabels.GetValueOrDefault(
+                issue.PrerequisiteCourseId,
+                new CourseLabel(
+                    issue.PrerequisiteCourseId,
+                    "未知课程",
+                    "未找到的先修课程"));
+            return new
+            {
+                Type = "Prerequisite",
+                issue.CourseId,
+                course.CourseName,
+                PrerequisiteCourseId = prerequisite.CourseId,
+                PrerequisiteCourseName = prerequisite.CourseName,
+                issue.PlannedSemester,
+                issue.PrerequisitePlannedSemester,
+                Message = issue.PrerequisitePlannedSemester.HasValue
+                    ? $"《{prerequisite.CourseName}》必须安排在《{course.CourseName}》之前。"
+                    : $"《{course.CourseName}》的先修课程《{prerequisite.CourseName}》尚未完成或安排。"
+            };
+        }).ToList();
+        var workloadWarnings = request.Terms
+            .Select(term => new
+            {
+                term.Semester,
+                Credits = term.CourseIds.Sum(courseId =>
+                    context.CourseById.GetValueOrDefault(courseId)?.Credits ?? 0)
+            })
+            .Where(x =>
+                x.Credits > AcademicPlanningRules.HeavySemesterCreditLimit)
+            .Select(x => new
+            {
+                Type = "Workload",
+                x.Semester,
+                x.Credits,
+                Message =
+                    $"第 {x.Semester} 学期安排了 {x.Credits:0.#} 学分，超过建议上限 {AcademicPlanningRules.HeavySemesterCreditLimit:0.#} 学分。"
+            })
+            .ToList();
+        var timingWarnings = selections
+            .Select(item => new
+            {
+                item.Semester,
+                Course = context.CourseById[item.CourseId]
+            })
+            .Where(x => x.Semester < x.Course.RecommendedSemester)
+            .Select(x => new
+            {
+                Type = "EarlyCourse",
+                x.Course.CourseId,
+                x.Course.CourseName,
+                x.Semester,
+                x.Course.RecommendedSemester,
+                Message =
+                    $"《{x.Course.CourseName}》早于培养方案建议学期修读，请确认课程开设条件。"
+            })
+            .ToList();
+
+        var unresolvedFailedCourseCount = context.FailedCourseIds.Count(
+            courseId => !projectedCourseIds.Contains(courseId));
+        var conclusion = GraduationAuditRules.Evaluate(
+            true,
+            context.Student.Status,
+            context.Plan.TotalCredits,
+            projectedEarnedCredits,
+            completion.RequirementCount,
+            completion.PassedRequirementCount,
+            unresolvedFailedCourseCount);
+        var latestPlannedSemester = plannedSemesters.Count == 0
+            ? context.NextSemester - 1
+            : plannedSemesters.Values.Max();
+        var estimatedSemester =
+            AcademicPlanningRules.EstimateCompletionSemester(
+                context.NextSemester,
+                latestPlannedSemester,
+                creditGap,
+                completion.RequirementCount -
+                completion.PassedRequirementCount);
+        var remainingRequiredSemesterFloor = context.Courses
+            .Where(course =>
+                course.Type == CurriculumCourseType.Required &&
+                !projectedCourseIds.Contains(course.CourseId))
+            .Select(course => course.RecommendedSemester)
+            .DefaultIfEmpty(estimatedSemester)
+            .Max();
+        estimatedSemester = Math.Max(
+            estimatedSemester,
+            remainingRequiredSemesterFloor);
+        var planCompletedCredits = context.Courses
+            .Where(x => projectedCourseIds.Contains(x.CourseId))
+            .Sum(x => x.Credits);
+
+        return Ok(new
+        {
+            Projected = new
+            {
+                EarnedCredits = projectedEarnedCredits,
+                PlanCompletedCredits = planCompletedCredits,
+                CreditGap = creditGap,
+                CompletionRate = context.Plan.TotalCredits <= 0
+                    ? 0
+                    : Math.Min(100, Math.Round(
+                        planCompletedCredits / context.Plan.TotalCredits * 100,
+                        1)),
+                completion.RequirementCount,
+                completion.PassedRequirementCount,
+                completion.MissingRequirements,
+                UnresolvedFailedCourseCount = unresolvedFailedCourseCount,
+                GraduationConclusion = conclusion,
+                EstimatedGraduationSemester = estimatedSemester,
+                EstimatedGraduationTerm = FormatSemester(
+                    context.Student.EnrollmentYear,
+                    estimatedSemester),
+                IsBeyondStandard =
+                    estimatedSemester >
+                    context.Plan.Major!.SchoolingYears * 2
+            },
+            Conflicts = conflicts,
+            Warnings = workloadWarnings.Cast<object>()
+                .Concat(timingWarnings)
+                .ToList(),
+            TermSummaries = request.Terms
+                .OrderBy(x => x.Semester)
+                .Select(term => new
+                {
+                    term.Semester,
+                    Label = FormatSemester(
+                        context.Student.EnrollmentYear,
+                        term.Semester),
+                    CourseCount = term.CourseIds.Count,
+                    Credits = term.CourseIds.Sum(courseId =>
+                        context.CourseById.GetValueOrDefault(courseId)?.Credits ??
+                        0)
+                })
+        });
+    }
+
+    private async Task<LoadResult> LoadAsync(CancellationToken cancellationToken)
+    {
+        var userId = currentUserDataScope.Current.UserId;
+        var student = await db.Students.AsNoTracking()
+            .Include(x => x.AdministrativeClass)
+            .ThenInclude(x => x!.Major)
+            .ThenInclude(x => x!.College)
+            .FirstOrDefaultAsync(x => x.UserId == userId, cancellationToken);
+        if (student is null)
+            return new LoadResult(
+                null,
+                ConflictProblem("当前账号尚未关联学生档案。"));
+
+        var plan = await db.CurriculumPlans.AsNoTracking()
+            .AsSplitQuery()
+            .Include(x => x.Major)
+            .Include(x => x.Modules)
+            .ThenInclude(x => x.Courses)
+            .ThenInclude(x => x.Course)
+            .ThenInclude(x => x!.Prerequisites)
+            .ThenInclude(x => x.PrerequisiteCourse)
+            .Where(x =>
+                x.MajorId == student.AdministrativeClass!.MajorId &&
+                x.EffectiveGrade == student.EnrollmentYear &&
+                x.Status == CurriculumPlanStatus.Published)
+            .OrderByDescending(x => x.PublishedAt)
+            .FirstOrDefaultAsync(cancellationToken);
+        if (plan is null)
+            return new LoadResult(
+                null,
+                ConflictProblem(
+                    $"{student.EnrollmentYear} 级{student.AdministrativeClass!.Major!.Name}尚未发布培养方案。"));
+
+        var courses = plan.Modules
+            .SelectMany(module => module.Courses.Select(item =>
+                new PlanningCourse(
+                    item.CourseId,
+                    item.Course!.Code,
+                    item.Course.Name,
+                    item.Course.Credits,
+                    item.RecommendedSemester,
+                    item.Type,
+                    module.Code,
+                    module.Name,
+                    item.Course.Prerequisites
+                        .Select(prerequisite => new CourseLabel(
+                            prerequisite.PrerequisiteCourseId,
+                            prerequisite.PrerequisiteCourse!.Code,
+                            prerequisite.PrerequisiteCourse.Name))
+                        .OrderBy(x => x.CourseCode)
+                        .ToList())))
+            .GroupBy(x => x.CourseId)
+            .Select(group => group.First())
+            .ToList();
+        var planCourseIds = courses.Select(x => x.CourseId).ToArray();
+
+        var gradeAttempts = await db.GradeRecords.AsNoTracking()
+            .Where(x =>
+                x.StudentId == student.Id &&
+                x.GradeSheet!.Status == GradeSheetStatus.Published)
+            .Select(x => new GradeAttempt(
+                x.GradeSheet!.TeachingTask!.CourseId,
+                x.GradeSheet.TeachingTask.Course!.Credits,
+                x.TotalScore,
+                x.ExamStatus))
+            .ToListAsync(cancellationToken);
+        var passedCourseIds = gradeAttempts
+            .Where(x => StudentCourseProgressRules.IsPassed(
+                new StudentCourseAttemptSnapshot(x.TotalScore, x.ExamStatus)))
+            .Select(x => x.CourseId)
+            .Distinct()
+            .ToHashSet();
+        var failedCourseIds = gradeAttempts
+            .GroupBy(x => x.CourseId)
+            .Where(group => !group.Any(x =>
+                StudentCourseProgressRules.IsPassed(
+                    new StudentCourseAttemptSnapshot(
+                        x.TotalScore,
+                        x.ExamStatus))))
+            .Select(group => group.Key)
+            .ToHashSet();
+        var earnedCredits = gradeAttempts
+            .Where(x => passedCourseIds.Contains(x.CourseId))
+            .GroupBy(x => x.CourseId)
+            .Sum(group => group.Max(x => x.Credits));
+
+        var inProgressCourseIds = await db.TeachingTasks.AsNoTracking()
+            .Where(task =>
+                task.Status == TeachingTaskStatus.Published &&
+                task.AcademicTerm!.IsCurrent &&
+                (task.Classes.Any(item =>
+                     item.AdministrativeClassId ==
+                     student.AdministrativeClassId) ||
+                 db.CourseEnrollments.Any(enrollment =>
+                     enrollment.StudentId == student.Id &&
+                     enrollment.Status == CourseEnrollmentStatus.Enrolled &&
+                     enrollment.CourseSelectionOffering!.TeachingTaskId ==
+                     task.Id)))
+            .Select(x => x.CourseId)
+            .Distinct()
+            .ToListAsync(cancellationToken);
+        var inProgressSet = inProgressCourseIds
+            .Where(planCourseIds.Contains)
+            .Where(courseId => !passedCourseIds.Contains(courseId))
+            .ToHashSet();
+
+        var attemptsByCourse = gradeAttempts
+            .Where(x => planCourseIds.Contains(x.CourseId))
+            .GroupBy(x => x.CourseId)
+            .ToDictionary(x => x.Key, x => x.ToList());
+        var statuses = courses.ToDictionary(
+            x => x.CourseId,
+            x => StudentCourseProgressRules.Evaluate(
+                attemptsByCourse.GetValueOrDefault(x.CourseId, [])
+                    .Select(attempt => new StudentCourseAttemptSnapshot(
+                        attempt.TotalScore,
+                        attempt.ExamStatus)),
+                inProgressSet.Contains(x.CourseId)).Status);
+        var currentTerm = await db.AcademicTerms.AsNoTracking()
+            .Where(x => x.IsCurrent)
+            .OrderByDescending(x => x.StartDate)
+            .FirstOrDefaultAsync(cancellationToken);
+        var currentSemester = CalculateCurrentSemester(
+            student.EnrollmentYear,
+            currentTerm);
+        var snapshots = courses.Select(x =>
+            new AcademicPlanningCourseSnapshot(
+                x.CourseId,
+                x.CourseName,
+                x.Credits,
+                x.RecommendedSemester,
+                x.Type,
+                x.Prerequisites.Select(p => p.CourseId).ToArray()))
+            .ToList();
+        var allLabels = courses
+            .Select(x => new CourseLabel(
+                x.CourseId,
+                x.CourseCode,
+                x.CourseName))
+            .Concat(courses.SelectMany(x => x.Prerequisites))
+            .GroupBy(x => x.CourseId)
+            .ToDictionary(x => x.Key, x => x.First());
+
+        return new LoadResult(
+            new PlanningContext(
+                student,
+                plan,
+                courses,
+                courses.ToDictionary(x => x.CourseId),
+                snapshots,
+                allLabels,
+                passedCourseIds,
+                inProgressSet,
+                failedCourseIds,
+                statuses,
+                earnedCredits,
+                currentSemester,
+                currentSemester + 1),
+            null);
+    }
+
+    private static int CalculateCurrentSemester(
+        int enrollmentYear,
+        AcademicTerm? currentTerm)
+    {
+        if (currentTerm is not null)
+        {
+            return Math.Max(
+                1,
+                currentTerm.Season == TermSeason.Autumn
+                    ? (currentTerm.StartDate.Year - enrollmentYear) * 2 + 1
+                    : (currentTerm.StartDate.Year - enrollmentYear - 1) * 2 + 2);
+        }
+
+        var today = DateOnly.FromDateTime(DateTime.Today);
+        return Math.Max(
+            1,
+            today.Month >= 8
+                ? (today.Year - enrollmentYear) * 2 + 1
+                : (today.Year - enrollmentYear - 1) * 2 + 2);
+    }
+
+    private static string FormatSemester(int enrollmentYear, int semester)
+    {
+        var startYear = enrollmentYear + (semester - 1) / 2;
+        var season = semester % 2 == 1 ? "秋季学期" : "春季学期";
+        return $"{startYear}—{startYear + 1} 学年{season}";
+    }
+
+    private ActionResult ConflictProblem(string detail) =>
+        Conflict(new ProblemDetails
+        {
+            Title = "无法进行学业规划",
+            Detail = detail,
+            Status = StatusCodes.Status409Conflict
+        });
+
+    private sealed record GradeAttempt(
+        Guid CourseId,
+        decimal Credits,
+        decimal? TotalScore,
+        GradeExamStatus ExamStatus);
+
+    private sealed record CourseLabel(
+        Guid CourseId,
+        string CourseCode,
+        string CourseName);
+
+    private sealed record PlanningCourse(
+        Guid CourseId,
+        string CourseCode,
+        string CourseName,
+        decimal Credits,
+        int RecommendedSemester,
+        CurriculumCourseType Type,
+        string ModuleCode,
+        string ModuleName,
+        IReadOnlyList<CourseLabel> Prerequisites);
+
+    private sealed record PlanningContext(
+        Student Student,
+        CurriculumPlan Plan,
+        IReadOnlyList<PlanningCourse> Courses,
+        IReadOnlyDictionary<Guid, PlanningCourse> CourseById,
+        IReadOnlyList<AcademicPlanningCourseSnapshot> CourseSnapshots,
+        IReadOnlyDictionary<Guid, CourseLabel> AllCourseLabels,
+        IReadOnlySet<Guid> PassedCourseIds,
+        IReadOnlySet<Guid> InProgressCourseIds,
+        IReadOnlySet<Guid> FailedCourseIds,
+        IReadOnlyDictionary<Guid, StudentCourseProgressStatus> StatusByCourse,
+        decimal EarnedCredits,
+        int CurrentSemester,
+        int NextSemester);
+
+    private sealed record LoadResult(
+        PlanningContext? Context,
+        ActionResult? Error);
+}
+
+public sealed record AcademicPlanningRequest(
+    IReadOnlyCollection<AcademicPlanningTermRequest> Terms);
+
+public sealed record AcademicPlanningTermRequest(
+    [Range(1, 30)] int Semester,
+    IReadOnlyCollection<Guid> CourseIds);

src/Jiaowu.Api/Controllers/CoursesController.cs

@@ -84,6 +84,17 @@ public sealed class CoursesController(
                 x.Nature,
                 x.AssessmentMethod,
                 x.Description,
+                PrerequisiteCourseIds = x.Prerequisites
+                    .OrderBy(item => item.PrerequisiteCourse!.Code)
+                    .Select(item => item.PrerequisiteCourseId),
+                Prerequisites = x.Prerequisites
+                    .OrderBy(item => item.PrerequisiteCourse!.Code)
+                    .Select(item => new
+                    {
+                        item.PrerequisiteCourseId,
+                        item.PrerequisiteCourse!.Code,
+                        item.PrerequisiteCourse.Name
+                    }),
                 x.IsEnabled,
                 x.SortOrder,
                 x.CreatedAt,
@@ -146,9 +157,6 @@ public sealed class CoursesController(
         CourseRequest request,
         CancellationToken cancellationToken)
     {
-        var validation = await ValidateAsync(request, cancellationToken);
-        if (validation is not null) return validation;
-
         var entity = new Course
         {
             Code = request.Code.Trim(),
@@ -166,6 +174,16 @@ public sealed class CoursesController(
             IsEnabled = request.IsEnabled,
             SortOrder = request.SortOrder
         };
+        var validation = await ValidateAsync(entity.Id, request, cancellationToken);
+        if (validation is not null) return validation;
+
+        entity.Prerequisites = NormalizePrerequisiteIds(request)
+            .Select(prerequisiteId => new CoursePrerequisite
+            {
+                CourseId = entity.Id,
+                PrerequisiteCourseId = prerequisiteId
+            })
+            .ToList();
         db.Courses.Add(entity);
         return await SaveAsync(entity.Id, true, cancellationToken);
     }
@@ -177,10 +195,12 @@ public sealed class CoursesController(
         CourseRequest request,
         CancellationToken cancellationToken)
     {
-        var entity = await db.Courses.FindAsync([id], cancellationToken);
+        var entity = await db.Courses
+            .Include(x => x.Prerequisites)
+            .FirstOrDefaultAsync(x => x.Id == id, cancellationToken);
         if (entity is null) return NotFound();
         if (!CanManage(entity.CollegeId, entity.Nature)) return Forbid();
-        var validation = await ValidateAsync(request, cancellationToken);
+        var validation = await ValidateAsync(id, request, cancellationToken);
         if (validation is not null) return validation;
 
         entity.Code = request.Code.Trim();
@@ -197,6 +217,19 @@ public sealed class CoursesController(
         entity.Description = Normalize(request.Description);
         entity.IsEnabled = request.IsEnabled;
         entity.SortOrder = request.SortOrder;
+        var prerequisiteIds = NormalizePrerequisiteIds(request).ToHashSet();
+        db.CoursePrerequisites.RemoveRange(
+            entity.Prerequisites.Where(x =>
+                !prerequisiteIds.Contains(x.PrerequisiteCourseId)));
+        foreach (var prerequisiteId in prerequisiteIds.Except(
+                     entity.Prerequisites.Select(x => x.PrerequisiteCourseId)))
+        {
+            entity.Prerequisites.Add(new CoursePrerequisite
+            {
+                CourseId = entity.Id,
+                PrerequisiteCourseId = prerequisiteId
+            });
+        }
         return await SaveAsync(entity.Id, false, cancellationToken);
     }
 
@@ -212,6 +245,7 @@ public sealed class CoursesController(
     }
 
     private async Task<ActionResult?> ValidateAsync(
+        Guid courseId,
         CourseRequest request,
         CancellationToken cancellationToken)
     {
@@ -224,9 +258,62 @@ public sealed class CoursesController(
             return ValidationProblem("所选课程分类不存在或已停用。");
         if (request.LectureHours + request.PracticeHours > request.TotalHours)
             return ValidationProblem("讲授学时与实践学时之和不能超过总学时。");
+
+        var prerequisiteIds = NormalizePrerequisiteIds(request).ToArray();
+        if (prerequisiteIds.Contains(courseId))
+            return ValidationProblem("课程不能把自身设置为先修课程。");
+        var accessiblePrerequisiteCount = await ScopedCourses()
+            .CountAsync(x =>
+                prerequisiteIds.Contains(x.Id) &&
+                x.IsEnabled,
+                cancellationToken);
+        if (accessiblePrerequisiteCount != prerequisiteIds.Length)
+            return ValidationProblem("包含不存在、已停用或不在当前数据范围内的先修课程。");
+        if (await CreatesPrerequisiteCycleAsync(
+                courseId,
+                prerequisiteIds,
+                cancellationToken))
+            return ValidationProblem("先修关系不能形成循环依赖。");
         return null;
     }
 
+    private async Task<bool> CreatesPrerequisiteCycleAsync(
+        Guid courseId,
+        IReadOnlyCollection<Guid> prerequisiteIds,
+        CancellationToken cancellationToken)
+    {
+        if (prerequisiteIds.Count == 0) return false;
+
+        var edges = await db.CoursePrerequisites.AsNoTracking()
+            .Where(x => x.CourseId != courseId)
+            .Select(x => new { x.CourseId, x.PrerequisiteCourseId })
+            .ToListAsync(cancellationToken);
+        var prerequisitesByCourse = edges
+            .GroupBy(x => x.CourseId)
+            .ToDictionary(
+                group => group.Key,
+                group => group.Select(x => x.PrerequisiteCourseId).ToArray());
+
+        foreach (var prerequisiteId in prerequisiteIds)
+        {
+            var pending = new Stack<Guid>();
+            var visited = new HashSet<Guid>();
+            pending.Push(prerequisiteId);
+            while (pending.TryPop(out var candidate))
+            {
+                if (candidate == courseId) return true;
+                if (!visited.Add(candidate) ||
+                    !prerequisitesByCourse.TryGetValue(candidate, out var next))
+                    continue;
+                foreach (var item in next) pending.Push(item);
+            }
+        }
+        return false;
+    }
+
+    private static IEnumerable<Guid> NormalizePrerequisiteIds(CourseRequest request) =>
+        (request.PrerequisiteCourseIds ?? []).Distinct();
+
     private IQueryable<Course> ScopedCourses()
     {
         var scope = currentUserDataScope.Current;
@@ -307,4 +394,5 @@ public sealed record CourseRequest(
     AssessmentMethod AssessmentMethod,
     [MaxLength(1000)] string? Description,
     bool IsEnabled,
-    int SortOrder);
+    int SortOrder,
+    IReadOnlyCollection<Guid>? PrerequisiteCourseIds = null);

src/Jiaowu.Api/Controllers/DashboardController.cs

@@ -1,11 +1,10 @@
-using System.Text.Json;
 using Jiaowu.Api.Domain.Academic;
-using Jiaowu.Api.Infrastructure.Caching;
+using Jiaowu.Api.Domain.Identity;
+using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Options;
 
 namespace Jiaowu.Api.Controllers;
 
@@ -14,89 +13,301 @@ namespace Jiaowu.Api.Controllers;
 [Route("api/dashboard")]
 public sealed class DashboardController(
     AppDbContext db,
-    IAppCache appCache,
-    IOptions<JsonOptions> jsonOptions) : ControllerBase
+    ICurrentUserDataScope currentUserDataScope) : ControllerBase
 {
     [HttpGet]
-    public async Task<ActionResult<object>> Get(CancellationToken cancellationToken)
+    public async Task<ActionResult<DashboardResponse>> Get(
+        CancellationToken cancellationToken)
     {
-        var response = await appCache.GetOrCreateAsync(
-            AppCacheKeys.Dashboard,
-            LoadAsync,
-            AppCacheProfile.Analytics,
-            [AppCacheTags.Analytics],
-            cancellationToken);
-        return response;
-    }
+        var scope = currentUserDataScope.Current;
+        Guid? restrictedCollegeId = scope.Scope == DataScope.All
+            ? null
+            : scope.CollegeId ?? Guid.Empty;
+        var collegeName = restrictedCollegeId.HasValue &&
+                          restrictedCollegeId.Value != Guid.Empty
+            ? await db.Colleges.AsNoTracking()
+                .Where(x => x.Id == restrictedCollegeId.Value)
+                .Select(x => x.Name)
+                .FirstOrDefaultAsync(cancellationToken)
+            : null;
 
-    private async Task<JsonElement> LoadAsync(CancellationToken cancellationToken)
-    {
         var currentTerm = await db.AcademicTerms
             .AsNoTracking()
             .Where(x => x.IsCurrent)
-            .Select(x => new { x.Id, x.Name, x.StartDate, x.EndDate })
+            .Select(x => new DashboardTerm(
+                x.Id,
+                x.Name,
+                x.StartDate,
+                x.EndDate))
             .FirstOrDefaultAsync(cancellationToken);
+        var currentTermId = currentTerm?.Id;
 
-        return JsonSerializer.SerializeToElement(
-            new
-            {
-                CurrentTerm = currentTerm,
-                Counts = new
-                {
-                    Campuses = await db.Campuses.CountAsync(cancellationToken),
-                    Colleges = await db.Colleges.CountAsync(cancellationToken),
-                    Majors = await db.Majors.CountAsync(cancellationToken),
-                    Classes = await db.AdministrativeClasses.CountAsync(cancellationToken),
-                    Classrooms = await db.Classrooms.CountAsync(cancellationToken),
-                    Teachers = await db.Teachers.CountAsync(cancellationToken),
-                    Students = await db.Students.CountAsync(cancellationToken),
-                    Courses = await db.Courses.CountAsync(cancellationToken),
-                    CurriculumPlans = await db.CurriculumPlans.CountAsync(cancellationToken),
-                    TeachingTasks = await db.TeachingTasks.CountAsync(cancellationToken),
-                    SchedulePlans = await db.SchedulePlans.CountAsync(cancellationToken),
-                    CourseSelectionRounds = await db.CourseSelectionRounds
-                        .CountAsync(cancellationToken),
-                    CourseSelectionOfferings = await db.CourseSelectionOfferings
-                        .CountAsync(cancellationToken),
-                    CourseEnrollments = await db.CourseEnrollments
-                        .CountAsync(
-                            x => x.Status == CourseEnrollmentStatus.Enrolled,
-                            cancellationToken),
-                    GradeSheets = await db.GradeSheets.CountAsync(cancellationToken),
-                    PublishedGradeSheets = await db.GradeSheets.CountAsync(
+        var students = db.Students.AsNoTracking()
+            .Where(x =>
+                !restrictedCollegeId.HasValue ||
+                x.AdministrativeClass!.Major!.CollegeId ==
+                restrictedCollegeId.Value);
+        var teachers = db.Teachers.AsNoTracking()
+            .Where(x =>
+                !restrictedCollegeId.HasValue ||
+                x.CollegeId == restrictedCollegeId.Value);
+        var courses = db.Courses.AsNoTracking()
+            .Where(x =>
+                !restrictedCollegeId.HasValue ||
+                x.CollegeId == restrictedCollegeId.Value);
+        var teachingTasks = db.TeachingTasks.AsNoTracking()
+            .Where(x =>
+                currentTermId.HasValue &&
+                x.AcademicTermId == currentTermId.Value &&
+                (!restrictedCollegeId.HasValue ||
+                 x.Course!.CollegeId == restrictedCollegeId.Value));
+        var gradeSheets = db.GradeSheets.AsNoTracking()
+            .Where(x =>
+                currentTermId.HasValue &&
+                x.TeachingTask!.AcademicTermId == currentTermId.Value &&
+                (!restrictedCollegeId.HasValue ||
+                 x.TeachingTask.Course!.CollegeId ==
+                 restrictedCollegeId.Value));
+        var enrollments = db.CourseEnrollments.AsNoTracking()
+            .Where(x =>
+                currentTermId.HasValue &&
+                x.Status == CourseEnrollmentStatus.Enrolled &&
+                x.CourseSelectionOffering!.CourseSelectionRound!
+                    .AcademicTermId == currentTermId.Value &&
+                (!restrictedCollegeId.HasValue ||
+                 x.CourseSelectionOffering.TeachingTask!.Course!.CollegeId ==
+                 restrictedCollegeId.Value));
+
+        var taskCount = await teachingTasks.CountAsync(cancellationToken);
+        var publishedTaskCount = await teachingTasks.CountAsync(
+            x => x.Status == TeachingTaskStatus.Published,
+            cancellationToken);
+        var scheduledTaskCount = currentTermId.HasValue
+            ? await db.ScheduleEntries.AsNoTracking()
+                .Where(x =>
+                    x.SchedulePlan!.AcademicTermId == currentTermId.Value &&
+                    x.SchedulePlan.Status == SchedulePlanStatus.Published &&
+                    (!restrictedCollegeId.HasValue ||
+                     x.TeachingTask!.Course!.CollegeId ==
+                     restrictedCollegeId.Value))
+                .Select(x => x.TeachingTaskId)
+                .Distinct()
+                .CountAsync(cancellationToken)
+            : 0;
+        var gradeSheetCount = await gradeSheets.CountAsync(cancellationToken);
+        var publishedGradeSheetCount = await gradeSheets.CountAsync(
             x => x.Status == GradeSheetStatus.Published,
+            cancellationToken);
+
+        var counts = new DashboardCounts(
+            await students.CountAsync(
+                x => x.Status == StudentStatus.Active,
                 cancellationToken),
-                    GradeRecords = await db.GradeRecords.CountAsync(cancellationToken),
-                    ExamPlans = await db.ExamPlans.CountAsync(cancellationToken),
-                    ExamSessions = await db.ExamSessions.CountAsync(cancellationToken),
-                    StudentStatusChanges = await db.StudentStatusChanges
-                        .CountAsync(cancellationToken),
-                    PendingStudentStatusChanges = await db.StudentStatusChanges.CountAsync(
-                        x => x.State == StudentStatusChangeState.Submitted ||
-                             x.State == StudentStatusChangeState.CounselorApproved ||
-                             x.State == StudentStatusChangeState.CollegeApproved,
+            await teachers.CountAsync(
+                x => x.Status == TeacherStatus.Active,
                 cancellationToken),
-                    GraduationAuditBatches = await db.GraduationAuditBatches
-                        .CountAsync(cancellationToken),
-                    PublishedGraduationAuditBatches = await db.GraduationAuditBatches
-                        .CountAsync(
-                            x => x.Status == GraduationAuditBatchStatus.Published,
+            await courses.CountAsync(
+                x => x.IsEnabled,
                 cancellationToken),
-                    DegreeAwardBatches = await db.DegreeAwardBatches
-                        .CountAsync(cancellationToken),
-                    PublishedDegreeAwardBatches = await db.DegreeAwardBatches
-                        .CountAsync(
-                            x => x.Status == DegreeAwardBatchStatus.Published,
+            taskCount,
+            publishedTaskCount,
+            scheduledTaskCount,
+            await enrollments.CountAsync(cancellationToken),
+            gradeSheetCount,
+            publishedGradeSheetCount,
+            await gradeSheets.CountAsync(
+                x => x.Status == GradeSheetStatus.Submitted,
                 cancellationToken),
-                    GraduationClearanceBatches = await db.GraduationClearanceBatches
-                        .CountAsync(cancellationToken),
-                    OpenGraduationClearanceBatches = await db.GraduationClearanceBatches
-                        .CountAsync(
-                            x => x.Status == GraduationClearanceBatchStatus.Open,
-                            cancellationToken),
-                    Users = await db.Users.CountAsync(cancellationToken)
+            currentTermId.HasValue
+                ? await db.CourseSelectionRounds.AsNoTracking().CountAsync(
+                    x => x.AcademicTermId == currentTermId.Value &&
+                         x.Status == CourseSelectionRoundStatus.Open,
+                    cancellationToken)
+                : 0);
+
+        var pending = await LoadPendingAsync(
+            scope,
+            restrictedCollegeId,
+            cancellationToken);
+
+        return Ok(new DashboardResponse(
+            BuildAudience(scope, collegeName),
+            currentTerm,
+            counts,
+            pending,
+            DateTime.UtcNow));
     }
-            },
-            jsonOptions.Value.JsonSerializerOptions);
+
+    private async Task<DashboardPending> LoadPendingAsync(
+        CurrentUserScope scope,
+        Guid? restrictedCollegeId,
+        CancellationToken cancellationToken)
+    {
+        var isSchoolManager =
+            scope.IsInRole(SystemRoles.SuperAdmin) ||
+            scope.IsInRole(SystemRoles.AcademicAdmin);
+        var isCollegeManager =
+            !isSchoolManager && scope.IsInRole(SystemRoles.CollegeAdmin);
+        if (!isSchoolManager && !isCollegeManager)
+            return new DashboardPending(0, 0, 0, 0, 0, 0, 0);
+
+        var teacherApplications = db.TeacherCourseApplications.AsNoTracking()
+            .Where(x =>
+                x.Status == TeacherCourseApplicationStatus.Pending &&
+                (!restrictedCollegeId.HasValue ||
+                 x.Teacher!.CollegeId == restrictedCollegeId.Value));
+        var gradeSheets = db.GradeSheets.AsNoTracking()
+            .Where(x =>
+                x.Status == GradeSheetStatus.Submitted &&
+                (!restrictedCollegeId.HasValue ||
+                 x.TeachingTask!.Course!.CollegeId ==
+                 restrictedCollegeId.Value));
+        var courseAdjustments = db.CourseAdjustments.AsNoTracking()
+            .Where(x =>
+                x.Status == CourseAdjustmentStatus.Submitted &&
+                (!restrictedCollegeId.HasValue ||
+                 x.TeachingTask!.Course!.CollegeId ==
+                 restrictedCollegeId.Value));
+        var studentStatusChanges = db.StudentStatusChanges.AsNoTracking()
+            .Where(x =>
+                x.State == (isCollegeManager
+                    ? StudentStatusChangeState.CounselorApproved
+                    : StudentStatusChangeState.CollegeApproved) &&
+                (!restrictedCollegeId.HasValue ||
+                 x.Student!.AdministrativeClass!.Major!.CollegeId ==
+                 restrictedCollegeId.Value));
+        var gradeModifications = db.GradeModifications.AsNoTracking()
+            .Where(x =>
+                x.Status == (isCollegeManager
+                    ? GradeModificationStatus.TeacherSubmitted
+                    : GradeModificationStatus.CollegeApproved) &&
+                (!restrictedCollegeId.HasValue ||
+                 x.GradeRecord!.GradeSheet!.TeachingTask!.Course!.CollegeId ==
+                 restrictedCollegeId.Value));
+
+        var generalApprovals =
+            await db.CourseExemptions.AsNoTracking().CountAsync(
+                x => x.Status == ApprovalStatus.Submitted &&
+                     (!restrictedCollegeId.HasValue ||
+                      x.TeachingTask!.Course!.CollegeId ==
+                      restrictedCollegeId.Value),
+                cancellationToken) +
+            await db.DeferredExams.AsNoTracking().CountAsync(
+                x => x.Status == ApprovalStatus.Submitted &&
+                     (!restrictedCollegeId.HasValue ||
+                      x.TeachingTask!.Course!.CollegeId ==
+                      restrictedCollegeId.Value),
+                cancellationToken) +
+            await db.CourseSubstitutions.AsNoTracking().CountAsync(
+                x => x.Status == ApprovalStatus.Submitted &&
+                     (!restrictedCollegeId.HasValue ||
+                      x.Student!.AdministrativeClass!.Major!.CollegeId ==
+                      restrictedCollegeId.Value),
+                cancellationToken) +
+            await db.AttendanceRecords.AsNoTracking().CountAsync(
+                x => x.AppealStatus == AttendanceAppealStatus.Pending &&
+                     (!restrictedCollegeId.HasValue ||
+                      x.Student!.AdministrativeClass!.Major!.CollegeId ==
+                      restrictedCollegeId.Value),
+                cancellationToken);
+
+        var classroomReservations = isCollegeManager &&
+                                    restrictedCollegeId.HasValue
+            ? await db.ClassroomReservations.AsNoTracking().CountAsync(
+                x => x.Status == ClassroomReservationStatus.Submitted &&
+                     x.ApplicantCollegeId == restrictedCollegeId.Value,
+                cancellationToken)
+            : 0;
+
+        return new DashboardPending(
+            await teacherApplications.CountAsync(cancellationToken),
+            await gradeSheets.CountAsync(cancellationToken),
+            await courseAdjustments.CountAsync(cancellationToken),
+            await studentStatusChanges.CountAsync(cancellationToken),
+            await gradeModifications.CountAsync(cancellationToken),
+            classroomReservations,
+            generalApprovals);
+    }
+
+    private static DashboardAudience BuildAudience(
+        CurrentUserScope scope,
+        string? collegeName)
+    {
+        if (scope.IsInRole(SystemRoles.SuperAdmin))
+            return new DashboardAudience(
+                "System",
+                "全域教务工作台",
+                "全校",
+                "统筹基础数据、教学运行与系统治理");
+        if (scope.IsInRole(SystemRoles.AcademicAdmin))
+            return new DashboardAudience(
+                "School",
+                "校级教务工作台",
+                "全校",
+                "聚焦跨学院教学运行与校级审核");
+        if (scope.IsInRole(SystemRoles.CollegeAdmin))
+            return new DashboardAudience(
+                "College",
+                "学院教务工作台",
+                collegeName ?? "本学院",
+                "聚焦本学院教学准备、过程审核与成绩归档");
+        if (scope.IsInRole(SystemRoles.Leader))
+            return new DashboardAudience(
+                "Leadership",
+                "教学运行观察台",
+                "全校",
+                "查看全校教学运行与质量数据");
+        if (scope.IsInRole(SystemRoles.Counselor))
+            return new DashboardAudience(
+                "Counselor",
+                "班级工作台",
+                collegeName ?? "所辖班级",
+                "处理学生过程管理与学业支持");
+        return new DashboardAudience(
+            "Teaching",
+            "教学工作台",
+            collegeName ?? "个人教学",
+            "查看课程运行并进入日常教学工作");
     }
 }
+
+public sealed record DashboardResponse(
+    DashboardAudience Audience,
+    DashboardTerm? CurrentTerm,
+    DashboardCounts Counts,
+    DashboardPending Pending,
+    DateTime GeneratedAt);
+
+public sealed record DashboardAudience(
+    string Level,
+    string Title,
+    string ScopeName,
+    string Description);
+
+public sealed record DashboardTerm(
+    Guid Id,
+    string Name,
+    DateOnly StartDate,
+    DateOnly EndDate);
+
+public sealed record DashboardCounts(
+    int Students,
+    int Teachers,
+    int Courses,
+    int TeachingTasks,
+    int PublishedTeachingTasks,
+    int ScheduledTeachingTasks,
+    int CourseEnrollments,
+    int GradeSheets,
+    int PublishedGradeSheets,
+    int SubmittedGradeSheets,
+    int OpenCourseSelectionRounds);
+
+public sealed record DashboardPending(
+    int TeacherApplications,
+    int GradeSheets,
+    int CourseAdjustments,
+    int StudentStatusChanges,
+    int GradeModifications,
+    int ClassroomReservations,
+    int GeneralApprovals);

src/Jiaowu.Api/Controllers/NotificationsController.cs

@@ -1,4 +1,7 @@
 using System.ComponentModel.DataAnnotations;
+using System.Data;
+using System.Net;
+using System.Text.RegularExpressions;
 using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
@@ -14,8 +17,11 @@ namespace Jiaowu.Api.Controllers;
 [Route("api/notifications")]
 public sealed class NotificationsController(
     AppDbContext db,
-    ICurrentUserDataScope currentUserDataScope) : ControllerBase
+    ICurrentUserDataScope currentUserDataScope,
+    ILogger<NotificationsController>? logger = null) : ControllerBase
 {
+    private const int MaximumSelectedRecipients = 500;
+    private const int NotificationBatchSize = 300;
     private const string Senders =
         SystemRoles.SuperAdmin + "," +
         SystemRoles.AcademicAdmin + "," +
@@ -106,17 +112,12 @@ public sealed class NotificationsController(
         var scope = currentUserDataScope.Current;
         if (IsSchoolAdministrator(scope))
         {
-            var recipientCount = await db.Users.AsNoTracking()
-                .CountAsync(
-                    x => x.IsEnabled && x.Id != scope.UserId,
-                    cancellationToken);
-            return Ok(new
-            {
-                AudienceType = MessageAudienceType.School,
-                AudienceName = "全校已启用账号",
-                RecipientCount = recipientCount,
-                TeachingTasks = Array.Empty<object>()
-            });
+            return Ok(await BuildAdministratorComposerAsync(
+                scope,
+                null,
+                MessageAudienceType.School,
+                "全校已启用账号",
+                cancellationToken));
         }
 
         if (scope.IsInRole(SystemRoles.CollegeAdmin) ||
@@ -138,19 +139,12 @@ public sealed class NotificationsController(
             if (college is null)
                 return ConflictProblem("当前账号关联的学院不存在。");
 
-            var recipientCount = await db.Users.AsNoTracking()
-                .CountAsync(
-                    x => x.IsEnabled &&
-                         x.Id != scope.UserId &&
-                         x.CollegeId == collegeId.Value,
-                    cancellationToken);
-            return Ok(new
-            {
-                AudienceType = MessageAudienceType.College,
-                AudienceName = $"{college}全院成员",
-                RecipientCount = recipientCount,
-                TeachingTasks = Array.Empty<object>()
-            });
+            return Ok(await BuildAdministratorComposerAsync(
+                scope,
+                collegeId.Value,
+                MessageAudienceType.College,
+                $"{college}全院成员",
+                cancellationToken));
         }
 
         if (scope.IsInRole(SystemRoles.Teacher))
@@ -195,6 +189,114 @@ public sealed class NotificationsController(
         return Forbid();
     }
 
+    [HttpGet("recipients")]
+    [Authorize(Roles = Senders)]
+    public async Task<ActionResult> GetRecipients(
+        Guid? collegeId,
+        string? role,
+        Guid? administrativeClassId,
+        Guid? teachingTaskId,
+        string? keyword,
+        int page = 1,
+        int pageSize = 30,
+        CancellationToken cancellationToken = default)
+    {
+        var scope = currentUserDataScope.Current;
+        if (scope.IsInRole(SystemRoles.Teacher) &&
+            !IsSchoolAdministrator(scope) &&
+            !scope.IsInRole(SystemRoles.CollegeAdmin) &&
+            !scope.IsInRole(SystemRoles.Counselor))
+        {
+            return Forbid();
+        }
+
+        var resolvedCollegeId = IsSchoolAdministrator(scope)
+            ? null
+            : await ResolveSenderCollegeIdAsync(scope, cancellationToken);
+        if (!IsSchoolAdministrator(scope) && !resolvedCollegeId.HasValue)
+            return ConflictProblem("当前账号未关联学院，暂时无法确定收件人范围。");
+
+        var filter = new MessageRecipientFilter(
+            collegeId,
+            Normalize(role),
+            administrativeClassId,
+            teachingTaskId,
+            Normalize(keyword));
+        if (filter.Role is not null && !SystemRoles.All.Contains(filter.Role))
+            return ValidationProblem("所选身份类型无效。");
+
+        page = Math.Max(1, page);
+        pageSize = Math.Clamp(pageSize, 10, 100);
+        var source = ApplyRecipientFilter(
+            ScopedRecipientQuery(scope, resolvedCollegeId),
+            filter);
+        var total = await source.CountAsync(cancellationToken);
+        var users = await source
+            .OrderBy(x => x.DisplayName)
+            .ThenBy(x => x.UserName)
+            .Skip((page - 1) * pageSize)
+            .Take(pageSize)
+            .Select(user => new
+            {
+                user.Id,
+                user.DisplayName,
+                user.UserName,
+                user.StaffNumber,
+                CollegeName = db.Colleges
+                    .Where(college => college.Id == user.CollegeId)
+                    .Select(college => college.Name)
+                    .FirstOrDefault(),
+                StudentNumber = db.Students
+                    .Where(student => student.UserId == user.Id)
+                    .Select(student => student.StudentNumber)
+                    .FirstOrDefault(),
+                ClassName = db.Students
+                    .Where(student => student.UserId == user.Id)
+                    .Select(student => student.AdministrativeClass!.Name)
+                    .FirstOrDefault(),
+                TeacherNumber = db.Teachers
+                    .Where(teacher => teacher.UserId == user.Id)
+                    .Select(teacher => teacher.TeacherNumber)
+                    .FirstOrDefault()
+            })
+            .ToListAsync(cancellationToken);
+        var userIds = users.Select(x => x.Id).ToArray();
+        var roleRows = await db.UserRoles.AsNoTracking()
+            .Where(x => userIds.Contains(x.UserId))
+            .Join(
+                db.Roles.AsNoTracking(),
+                userRole => userRole.RoleId,
+                roleEntity => roleEntity.Id,
+                (userRole, roleEntity) => new
+                {
+                    userRole.UserId,
+                    RoleName = roleEntity.Name!
+                })
+            .ToListAsync(cancellationToken);
+        var rolesByUser = roleRows
+            .GroupBy(x => x.UserId)
+            .ToDictionary(
+                group => group.Key,
+                group => group.Select(x => x.RoleName).Distinct().ToArray());
+
+        return Ok(new
+        {
+            Items = users.Select(user => new
+            {
+                user.Id,
+                user.DisplayName,
+                user.UserName,
+                Number = user.StudentNumber ?? user.TeacherNumber ?? user.StaffNumber,
+                user.CollegeName,
+                user.ClassName,
+                Roles = rolesByUser.GetValueOrDefault(user.Id, [])
+            }),
+            Total = total,
+            Page = page,
+            PageSize = pageSize
+        });
+    }
+
     [HttpPost("send")]
     [Authorize(Roles = Senders)]
     public async Task<ActionResult> Send(
@@ -205,8 +307,10 @@ public sealed class NotificationsController(
         var content = request.Content.Trim();
         if (title.Length == 0)
             return ValidationProblem("请填写消息标题。");
-        if (content.Length == 0)
+        if (PlainText(content).Length == 0)
             return ValidationProblem("请填写消息正文。");
+        if (content.Length > 20000)
+            return ValidationProblem("消息正文过长，请精简至 20000 个字符以内。");
         var scope = currentUserDataScope.Current;
         MessageAudienceType audienceType;
         Guid? audienceId = null;
@@ -215,12 +319,16 @@ public sealed class NotificationsController(
 
         if (IsSchoolAdministrator(scope))
         {
-            audienceType = MessageAudienceType.School;
-            audienceName = "全校已启用账号";
-            recipientIds = await db.Users.AsNoTracking()
-                .Where(x => x.IsEnabled && x.Id != scope.UserId)
-                .Select(x => x.Id)
-                .ToListAsync(cancellationToken);
+            var result = await ResolveAdministratorRecipientsAsync(
+                scope,
+                null,
+                request,
+                "全校已启用账号",
+                cancellationToken);
+            if (result.Error is not null) return result.Error;
+            audienceType = result.AudienceType;
+            audienceName = result.AudienceName!;
+            recipientIds = result.RecipientIds!;
         }
         else if (scope.IsInRole(SystemRoles.CollegeAdmin) ||
                  scope.IsInRole(SystemRoles.Counselor))
@@ -241,16 +349,19 @@ public sealed class NotificationsController(
             if (collegeName is null)
                 return ConflictProblem("当前账号关联的学院不存在。");
 
-            audienceType = MessageAudienceType.College;
-            audienceId = collegeId.Value;
-            audienceName = $"{collegeName}全院成员";
-            recipientIds = await db.Users.AsNoTracking()
-                .Where(x =>
-                    x.IsEnabled &&
-                    x.Id != scope.UserId &&
-                    x.CollegeId == collegeId.Value)
-                .Select(x => x.Id)
-                .ToListAsync(cancellationToken);
+            var result = await ResolveAdministratorRecipientsAsync(
+                scope,
+                collegeId.Value,
+                request,
+                $"{collegeName}全院成员",
+                cancellationToken);
+            if (result.Error is not null) return result.Error;
+            audienceType = result.AudienceType;
+            audienceId = audienceType == MessageAudienceType.College
+                ? collegeId.Value
+                : null;
+            audienceName = result.AudienceName!;
+            recipientIds = result.RecipientIds!;
         }
         else if (scope.IsInRole(SystemRoles.Teacher))
         {
@@ -305,17 +416,31 @@ public sealed class NotificationsController(
             RecipientCount = recipientIds.Count,
             LinkUrl = null
         };
-        dispatch.Notifications = recipientIds.Select(userId => new Notification
+        try
+        {
+            return await db.ExecuteInRetriableTransactionAsync<ActionResult>(
+                async transaction =>
+                {
+                    db.MessageDispatches.Add(dispatch);
+                    await db.SaveChangesAsync(cancellationToken);
+                    db.ChangeTracker.Clear();
+
+                    foreach (var batch in recipientIds.Chunk(NotificationBatchSize))
+                    {
+                        db.Notifications.AddRange(batch.Select(userId => new Notification
                         {
                             UserId = userId,
                             Title = title,
                             Content = content,
                             Category = NotificationCategory.General,
-            LinkUrl = null
-        }).ToList();
-
-        db.MessageDispatches.Add(dispatch);
+                            LinkUrl = null,
+                            MessageDispatchId = dispatch.Id
+                        }));
                         await db.SaveChangesAsync(cancellationToken);
+                        db.ChangeTracker.Clear();
+                    }
+
+                    await transaction.CommitAsync(cancellationToken);
                     return Ok(new
                     {
                         dispatch.Id,
@@ -323,6 +448,22 @@ public sealed class NotificationsController(
                         dispatch.RecipientCount,
                         dispatch.CreatedAt
                     });
+                },
+                cancellationToken,
+                IsolationLevel.ReadCommitted);
+        }
+        catch (DbUpdateException exception)
+        {
+            logger?.LogError(
+                exception,
+                "Failed to send notification dispatch {DispatchId} to {RecipientCount} recipients.",
+                dispatch.Id,
+                recipientIds.Count);
+            return Problem(
+                title: "消息未能发送",
+                detail: "消息数据保存失败。请确认数据库已完成最新升级后重试；本次消息没有发送。",
+                statusCode: StatusCodes.Status503ServiceUnavailable);
+        }
     }
 
     [HttpGet("sent")]
@@ -433,6 +574,286 @@ public sealed class NotificationsController(
         scope.IsInRole(SystemRoles.SuperAdmin) ||
         scope.IsInRole(SystemRoles.AcademicAdmin);
 
+    private async Task<object> BuildAdministratorComposerAsync(
+        CurrentUserScope scope,
+        Guid? fixedCollegeId,
+        MessageAudienceType audienceType,
+        string audienceName,
+        CancellationToken cancellationToken)
+    {
+        var colleges = await db.Colleges.AsNoTracking()
+            .Where(x => !fixedCollegeId.HasValue || x.Id == fixedCollegeId.Value)
+            .OrderBy(x => x.Code)
+            .Select(x => new { x.Id, x.Code, x.Name })
+            .ToListAsync(cancellationToken);
+        var administrativeClasses = await db.AdministrativeClasses.AsNoTracking()
+            .Where(x =>
+                x.IsEnabled &&
+                (!fixedCollegeId.HasValue ||
+                 x.Major!.CollegeId == fixedCollegeId.Value))
+            .OrderByDescending(x => x.Grade)
+            .ThenBy(x => x.Code)
+            .Select(x => new
+            {
+                x.Id,
+                x.Code,
+                x.Name,
+                x.Grade,
+                CollegeId = x.Major!.CollegeId
+            })
+            .ToListAsync(cancellationToken);
+        var teachingTasks = await db.TeachingTasks.AsNoTracking()
+            .Where(x =>
+                x.Status != TeachingTaskStatus.Draft &&
+                (!fixedCollegeId.HasValue ||
+                 x.Course!.CollegeId == fixedCollegeId.Value))
+            .OrderByDescending(x => x.AcademicTerm!.IsCurrent)
+            .ThenByDescending(x => x.AcademicTerm!.StartDate)
+            .ThenBy(x => x.TaskNumber)
+            .Select(x => new
+            {
+                x.Id,
+                x.TaskNumber,
+                CourseName = x.Course!.Name,
+                TermName = x.AcademicTerm!.Name,
+                CollegeId = x.Course.CollegeId
+            })
+            .ToListAsync(cancellationToken);
+        var recipientCount = await ScopedRecipientQuery(scope, fixedCollegeId)
+            .CountAsync(cancellationToken);
+
+        return new
+        {
+            AudienceType = audienceType,
+            AudienceName = audienceName,
+            RecipientCount = recipientCount,
+            CanFilterRecipients = true,
+            MaximumSelectedRecipients,
+            Colleges = colleges,
+            Roles = RoleOptions,
+            AdministrativeClasses = administrativeClasses,
+            TeachingTasks = teachingTasks
+        };
+    }
+
+    private IQueryable<ApplicationUser> ScopedRecipientQuery(
+        CurrentUserScope scope,
+        Guid? fixedCollegeId)
+    {
+        var source = db.Users.AsNoTracking()
+            .Where(x => x.IsEnabled && x.Id != scope.UserId);
+        if (IsSchoolAdministrator(scope)) return source;
+        if (!fixedCollegeId.HasValue) return source.Where(_ => false);
+        var collegeId = fixedCollegeId.Value;
+        return source.Where(user =>
+            user.CollegeId == collegeId ||
+            db.Students.Any(student =>
+                student.UserId == user.Id &&
+                student.AdministrativeClass!.Major!.CollegeId == collegeId) ||
+            db.Teachers.Any(teacher =>
+                teacher.UserId == user.Id &&
+                teacher.CollegeId == collegeId));
+    }
+
+    private IQueryable<ApplicationUser> ApplyRecipientFilter(
+        IQueryable<ApplicationUser> source,
+        MessageRecipientFilter? filter)
+    {
+        if (filter is null) return source;
+        if (filter.CollegeId.HasValue)
+        {
+            var collegeId = filter.CollegeId.Value;
+            source = source.Where(user =>
+                user.CollegeId == collegeId ||
+                db.Students.Any(student =>
+                    student.UserId == user.Id &&
+                    student.AdministrativeClass!.Major!.CollegeId == collegeId) ||
+                db.Teachers.Any(teacher =>
+                    teacher.UserId == user.Id &&
+                    teacher.CollegeId == collegeId));
+        }
+        if (!string.IsNullOrWhiteSpace(filter.Role))
+        {
+            var role = filter.Role;
+            source = source.Where(user =>
+                db.UserRoles.Any(userRole =>
+                    userRole.UserId == user.Id &&
+                    db.Roles.Any(roleEntity =>
+                        roleEntity.Id == userRole.RoleId &&
+                        roleEntity.Name == role)));
+        }
+        if (filter.AdministrativeClassId.HasValue)
+        {
+            var classId = filter.AdministrativeClassId.Value;
+            source = source.Where(user =>
+                db.Students.Any(student =>
+                    student.UserId == user.Id &&
+                    student.AdministrativeClassId == classId));
+        }
+        if (filter.TeachingTaskId.HasValue)
+        {
+            var taskId = filter.TeachingTaskId.Value;
+            source = source.Where(user =>
+                db.Students.Any(student =>
+                    student.UserId == user.Id &&
+                    (db.TeachingTaskClasses.Any(item =>
+                         item.TeachingTaskId == taskId &&
+                         item.AdministrativeClassId ==
+                         student.AdministrativeClassId) ||
+                     db.CourseEnrollments.Any(enrollment =>
+                         enrollment.StudentId == student.Id &&
+                         enrollment.Status == CourseEnrollmentStatus.Enrolled &&
+                         enrollment.CourseSelectionOffering!.TeachingTaskId ==
+                         taskId))));
+        }
+        if (!string.IsNullOrWhiteSpace(filter.Keyword))
+        {
+            var keyword = filter.Keyword;
+            source = source.Where(user =>
+                user.DisplayName.Contains(keyword) ||
+                (user.UserName != null && user.UserName.Contains(keyword)) ||
+                (user.StaffNumber != null && user.StaffNumber.Contains(keyword)) ||
+                db.Students.Any(student =>
+                    student.UserId == user.Id &&
+                    (student.Name.Contains(keyword) ||
+                     student.StudentNumber.Contains(keyword))) ||
+                db.Teachers.Any(teacher =>
+                    teacher.UserId == user.Id &&
+                    (teacher.Name.Contains(keyword) ||
+                     teacher.TeacherNumber.Contains(keyword))));
+        }
+
+        return source;
+    }
+
+    private async Task<RecipientResolution> ResolveAdministratorRecipientsAsync(
+        CurrentUserScope scope,
+        Guid? fixedCollegeId,
+        SendMessageRequest request,
+        string defaultAudienceName,
+        CancellationToken cancellationToken)
+    {
+        var source = ScopedRecipientQuery(scope, fixedCollegeId);
+        if (request.RecipientMode == MessageRecipientMode.Scope)
+        {
+            return new RecipientResolution(
+                fixedCollegeId.HasValue
+                    ? MessageAudienceType.College
+                    : MessageAudienceType.School,
+                defaultAudienceName,
+                await source.Select(x => x.Id).ToListAsync(cancellationToken),
+                null);
+        }
+
+        if (request.RecipientMode == MessageRecipientMode.Filtered)
+        {
+            if (request.RecipientFilter?.Role is not null &&
+                !SystemRoles.All.Contains(request.RecipientFilter.Role))
+            {
+                return new RecipientResolution(
+                    default,
+                    null,
+                    null,
+                    ValidationProblem("所选身份类型无效。"));
+            }
+            var recipientIds = await ApplyRecipientFilter(
+                    source,
+                    request.RecipientFilter)
+                .Select(x => x.Id)
+                .ToListAsync(cancellationToken);
+            return new RecipientResolution(
+                MessageAudienceType.Custom,
+                BuildFilteredAudienceName(request.RecipientFilter),
+                recipientIds,
+                null);
+        }
+
+        if (request.RecipientMode == MessageRecipientMode.Selected)
+        {
+            var requestedIds = request.RecipientUserIds?
+                .Distinct()
+                .ToArray() ?? [];
+            if (requestedIds.Length == 0)
+            {
+                return new RecipientResolution(
+                    default,
+                    null,
+                    null,
+                    ValidationProblem("请至少选择一名收件人。"));
+            }
+            if (requestedIds.Length > MaximumSelectedRecipients)
+            {
+                return new RecipientResolution(
+                    default,
+                    null,
+                    null,
+                    ValidationProblem(
+                        $"单次最多指定 {MaximumSelectedRecipients} 名收件人。"));
+            }
+
+            var authorizedIds = await source
+                .Where(x => requestedIds.Contains(x.Id))
+                .Select(x => x.Id)
+                .ToListAsync(cancellationToken);
+            if (authorizedIds.Count != requestedIds.Length)
+            {
+                return new RecipientResolution(
+                    default,
+                    null,
+                    null,
+                    ValidationProblem("所选收件人包含无权限访问或已停用的账号。"));
+            }
+
+            return new RecipientResolution(
+                MessageAudienceType.Custom,
+                $"指定收件人（{authorizedIds.Count} 人）",
+                authorizedIds,
+                null);
+        }
+
+        return new RecipientResolution(
+            default,
+            null,
+            null,
+            ValidationProblem("请选择有效的收件方式。"));
+    }
+
+    private static string BuildFilteredAudienceName(MessageRecipientFilter? filter)
+    {
+        if (filter is null) return "当前权限范围内全部账号";
+        var parts = new List<string>();
+        if (filter.CollegeId.HasValue) parts.Add("指定学院");
+        if (filter.Role is not null)
+            parts.Add(RoleOptions.FirstOrDefault(x => x.Value == filter.Role)?.Label ??
+                      filter.Role);
+        if (filter.AdministrativeClassId.HasValue) parts.Add("指定行政班");
+        if (filter.TeachingTaskId.HasValue) parts.Add("指定教学班");
+        if (filter.Keyword is not null) parts.Add($"关键词“{filter.Keyword}”");
+        return parts.Count == 0
+            ? "当前权限范围内全部账号"
+            : string.Join(" · ", parts);
+    }
+
+    private static string PlainText(string html)
+    {
+        var withoutTags = Regex.Replace(html, "<[^>]+>", " ");
+        return WebUtility.HtmlDecode(withoutTags).Trim();
+    }
+
+    private static string? Normalize(string? value) =>
+        string.IsNullOrWhiteSpace(value) ? null : value.Trim();
+
+    private static readonly RoleOption[] RoleOptions =
+    [
+        new(SystemRoles.Student, "学生"),
+        new(SystemRoles.Teacher, "任课教师"),
+        new(SystemRoles.Counselor, "辅导员"),
+        new(SystemRoles.CollegeAdmin, "学院管理员"),
+        new(SystemRoles.AcademicAdmin, "校级教务管理员"),
+        new(SystemRoles.Leader, "校领导"),
+        new(SystemRoles.SuperAdmin, "超级管理员")
+    ];
+
     private ActionResult ConflictProblem(string detail) =>
         Conflict(new ProblemDetails
         {
@@ -451,9 +872,34 @@ public sealed class NotificationsController(
 }
 
 public sealed record SendMessageRequest(
-    [property: Required, StringLength(200)] string Title,
-    [property: Required, StringLength(1000)] string Content,
-    Guid? TeachingTaskId = null);
+    [Required, StringLength(200)] string Title,
+    [Required, StringLength(20000)] string Content,
+    Guid? TeachingTaskId = null,
+    MessageRecipientMode RecipientMode = MessageRecipientMode.Scope,
+    MessageRecipientFilter? RecipientFilter = null,
+    IReadOnlyCollection<Guid>? RecipientUserIds = null);
+
+public sealed record MessageRecipientFilter(
+    Guid? CollegeId = null,
+    string? Role = null,
+    Guid? AdministrativeClassId = null,
+    Guid? TeachingTaskId = null,
+    string? Keyword = null);
+
+public enum MessageRecipientMode
+{
+    Scope = 1,
+    Filtered = 2,
+    Selected = 3
+}
+
+public sealed record RoleOption(string Value, string Label);
+
+internal sealed record RecipientResolution(
+    MessageAudienceType AudienceType,
+    string? AudienceName,
+    List<Guid>? RecipientIds,
+    ActionResult? Error);
 
 /// <summary>
 /// Centralized helper to send notifications across the app.

src/Jiaowu.Api/Controllers/OperationsController.cs

@@ -0,0 +1,519 @@
+using System.ComponentModel.DataAnnotations;
+using Jiaowu.Api.Contracts;
+using Jiaowu.Api.Domain.Academic;
+using Jiaowu.Api.Domain.Identity;
+using Jiaowu.Api.Domain.System;
+using Jiaowu.Api.Infrastructure.Operations;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+
+namespace Jiaowu.Api.Controllers;
+
+[ApiController]
+[Authorize(Roles = SystemRoles.SuperAdmin)]
+[Route("api/operations")]
+public sealed class OperationsController(
+    AppDbContext db,
+    OperationalHealthService healthService,
+    DatabaseBackupService backupService,
+    OperationsOptions options) : ControllerBase
+{
+    [HttpGet("summary")]
+    public async Task<ActionResult<OperationsSummary>> GetSummary(
+        CancellationToken cancellationToken)
+    {
+        var since = DateTime.UtcNow.AddHours(-24);
+        var health = await healthService.CheckAsync(cancellationToken);
+        var backups = await backupService.ListAsync(cancellationToken);
+        var auditCount = await db.AuditLogs.AsNoTracking()
+            .CountAsync(x => x.CreatedAt >= since, cancellationToken);
+        var serverErrorCount = await db.AuditLogs.AsNoTracking()
+            .CountAsync(
+                x => x.CreatedAt >= since && x.StatusCode >= 500,
+                cancellationToken);
+        var failedJobCount = await CountFailedJobsAsync(
+            DateTime.UtcNow.AddDays(-7),
+            cancellationToken);
+        var alerts = await BuildAlertsAsync(
+            health,
+            backups,
+            serverErrorCount,
+            failedJobCount,
+            cancellationToken);
+        return Ok(new OperationsSummary(
+            DateTime.UtcNow,
+            health,
+            new OperationsCounters(
+                auditCount,
+                serverErrorCount,
+                failedJobCount,
+                alerts.Count(x => x.Severity == "critical")),
+            alerts,
+            backups.FirstOrDefault()));
+    }
+
+    [HttpGet("health")]
+    public async Task<ActionResult<OperationalHealthSnapshot>> GetHealth(
+        CancellationToken cancellationToken) =>
+        Ok(await healthService.CheckAsync(cancellationToken));
+
+    [HttpGet("audit-logs")]
+    public async Task<ActionResult<PagedResult<AuditLogItem>>> GetAuditLogs(
+        [FromQuery] int page = 1,
+        [FromQuery] int pageSize = 20,
+        [FromQuery] string? method = null,
+        [FromQuery] int? statusCode = null,
+        [FromQuery] string? userName = null,
+        [FromQuery] string? path = null,
+        [FromQuery] DateTime? from = null,
+        [FromQuery] DateTime? to = null,
+        CancellationToken cancellationToken = default)
+    {
+        var pagingError = ValidatePaging(page, pageSize);
+        if (pagingError is not null) return pagingError;
+        var rangeError = ValidateRange(from, to);
+        if (rangeError is not null) return rangeError;
+
+        var query = db.AuditLogs.AsNoTracking().AsQueryable();
+        if (!string.IsNullOrWhiteSpace(method))
+        {
+            var normalizedMethod = method.Trim().ToUpperInvariant();
+            query = query.Where(x => x.Method == normalizedMethod);
+        }
+        if (statusCode.HasValue)
+            query = query.Where(x => x.StatusCode == statusCode.Value);
+        if (!string.IsNullOrWhiteSpace(userName))
+        {
+            var normalizedUser = userName.Trim();
+            query = query.Where(x =>
+                x.UserName != null && x.UserName.Contains(normalizedUser));
+        }
+        if (!string.IsNullOrWhiteSpace(path))
+        {
+            var normalizedPath = path.Trim();
+            query = query.Where(x => x.Path.Contains(normalizedPath));
+        }
+        query = query.Where(x =>
+            x.CreatedAt >= (from ?? DateTime.UtcNow.AddDays(-1)));
+        if (to.HasValue)
+            query = query.Where(x => x.CreatedAt <= to.Value);
+
+        var total = await query.CountAsync(cancellationToken);
+        var items = await query
+            .OrderByDescending(x => x.CreatedAt)
+            .Skip((page - 1) * pageSize)
+            .Take(pageSize)
+            .Select(x => new AuditLogItem(
+                x.Id,
+                x.UserName,
+                x.Method,
+                x.Path,
+                x.StatusCode,
+                x.IpAddress,
+                x.CreatedAt))
+            .ToListAsync(cancellationToken);
+        return Ok(new PagedResult<AuditLogItem>(items, total, page, pageSize));
+    }
+
+    [HttpGet("failed-jobs")]
+    public async Task<ActionResult<PagedResult<FailedBackgroundJobItem>>>
+        GetFailedJobs(
+            [FromQuery] int page = 1,
+            [FromQuery] int pageSize = 20,
+            [FromQuery] string? kind = null,
+            [FromQuery] DateTime? from = null,
+            [FromQuery] DateTime? to = null,
+            CancellationToken cancellationToken = default)
+    {
+        var pagingError = ValidatePaging(page, pageSize);
+        if (pagingError is not null) return pagingError;
+        var rangeError = ValidateRange(from, to);
+        if (rangeError is not null) return rangeError;
+
+        var normalizedKind = NormalizeJobKind(kind);
+        if (kind is not null && normalizedKind is null)
+            return ValidationProblem("后台任务类型无效。");
+
+        var effectiveFrom = from ?? DateTime.UtcNow.AddDays(-30);
+        var take = checked(page * pageSize);
+        var rows = new List<FailedBackgroundJobItem>();
+        var total = 0;
+
+        if (normalizedKind is null or "AutomaticSchedule")
+        {
+            var query = db.AutomaticScheduleJobs.AsNoTracking()
+                .Where(x =>
+                    x.Status == AutomaticScheduleJobStatus.Failed &&
+                    x.CreatedAt >= effectiveFrom);
+            if (to.HasValue) query = query.Where(x => x.CreatedAt <= to.Value);
+            total += await query.CountAsync(cancellationToken);
+            rows.AddRange(await query
+                .OrderByDescending(x => x.CompletedAt ?? x.UpdatedAt)
+                .Take(take)
+                .Select(x => new FailedBackgroundJobItem(
+                    x.Id,
+                    "AutomaticSchedule",
+                    "自动排课",
+                    x.SchedulePlan == null ? "排课方案" : x.SchedulePlan.Name,
+                    x.ErrorMessage ?? "任务失败但未记录错误详情。",
+                    x.CreatedAt,
+                    x.StartedAt,
+                    x.CompletedAt,
+                    0))
+                .ToListAsync(cancellationToken));
+        }
+
+        if (normalizedKind is null or "SchedulePublish")
+        {
+            var query = db.SchedulePublishJobs.AsNoTracking()
+                .Where(x =>
+                    x.Status == SchedulePublishJobStatus.Failed &&
+                    x.CreatedAt >= effectiveFrom);
+            if (to.HasValue) query = query.Where(x => x.CreatedAt <= to.Value);
+            total += await query.CountAsync(cancellationToken);
+            rows.AddRange(await query
+                .OrderByDescending(x => x.CompletedAt ?? x.UpdatedAt)
+                .Take(take)
+                .Select(x => new FailedBackgroundJobItem(
+                    x.Id,
+                    "SchedulePublish",
+                    "课表发布",
+                    x.SchedulePlan == null ? "排课方案" : x.SchedulePlan.Name,
+                    x.ErrorMessage ?? "任务失败但未记录错误详情。",
+                    x.CreatedAt,
+                    x.StartedAt,
+                    x.CompletedAt,
+                    0))
+                .ToListAsync(cancellationToken));
+        }
+
+        if (normalizedKind is null or "MakeupExamAuto")
+        {
+            var query = db.MakeupExamAutoJobs.AsNoTracking()
+                .Where(x =>
+                    x.Status == MakeupExamAutoJobStatus.Failed &&
+                    x.CreatedAt >= effectiveFrom);
+            if (to.HasValue) query = query.Where(x => x.CreatedAt <= to.Value);
+            total += await query.CountAsync(cancellationToken);
+            rows.AddRange(await query
+                .OrderByDescending(x => x.CompletedAt ?? x.UpdatedAt)
+                .Take(take)
+                .Select(x => new FailedBackgroundJobItem(
+                    x.Id,
+                    "MakeupExamAuto",
+                    "补考自动安排",
+                    x.MakeupExamPlan == null ? "补考计划" : x.MakeupExamPlan.Name,
+                    x.ErrorMessage ?? "任务失败但未记录错误详情。",
+                    x.CreatedAt,
+                    x.StartedAt,
+                    x.CompletedAt,
+                    0))
+                .ToListAsync(cancellationToken));
+        }
+
+        var pageItems = rows
+            .OrderByDescending(x => x.CompletedAt ?? x.CreatedAt)
+            .Skip((page - 1) * pageSize)
+            .Take(pageSize)
+            .ToArray();
+        if (pageItems.Length > 0)
+        {
+            var ids = pageItems.Select(x => x.Id).ToArray();
+            var attempts = await db.BackgroundJobOutboxMessages.AsNoTracking()
+                .Where(x => ids.Contains(x.JobId))
+                .Select(x => new { x.JobId, x.ProcessingAttempts })
+                .ToDictionaryAsync(x => x.JobId, x => x.ProcessingAttempts,
+                    cancellationToken);
+            pageItems = pageItems
+                .Select(x => x with
+                {
+                    ProcessingAttempts = attempts.GetValueOrDefault(x.Id)
+                })
+                .ToArray();
+        }
+
+        return Ok(new PagedResult<FailedBackgroundJobItem>(
+            pageItems,
+            total,
+            page,
+            pageSize));
+    }
+
+    [HttpGet("backups")]
+    public async Task<ActionResult<IReadOnlyCollection<BackupArtifact>>> GetBackups(
+        CancellationToken cancellationToken) =>
+        Ok(await backupService.ListAsync(cancellationToken));
+
+    [HttpPost("backups")]
+    public async Task<ActionResult<BackupArtifact>> CreateBackup(
+        CreateBackupRequest request,
+        CancellationToken cancellationToken)
+    {
+        try
+        {
+            var artifact = await backupService.CreateAsync(
+                request.Note,
+                cancellationToken);
+            return CreatedAtAction(
+                nameof(GetBackups),
+                new { id = artifact.Id },
+                artifact);
+        }
+        catch (Exception exception) when (exception is not OperationCanceledException)
+        {
+            return Problem(
+                title: "数据库备份失败",
+                detail: SafeMessage(exception),
+                statusCode: StatusCodes.Status503ServiceUnavailable);
+        }
+    }
+
+    [HttpPost("backups/{backupId}/restore-drill")]
+    public async Task<ActionResult<RestoreDrillResult>> RunRestoreDrill(
+        string backupId,
+        RestoreDrillRequest request,
+        CancellationToken cancellationToken)
+    {
+        if (!request.Confirmation.Equals(
+                "RESTORE_DRILL",
+                StringComparison.Ordinal))
+        {
+            return ValidationProblem(
+                "恢复演练必须明确确认，且不会覆盖当前业务数据库。");
+        }
+
+        try
+        {
+            return Ok(await backupService.RunRestoreDrillAsync(
+                backupId,
+                cancellationToken));
+        }
+        catch (FileNotFoundException)
+        {
+            return NotFound(new ProblemDetails
+            {
+                Title = "备份不存在",
+                Detail = "指定备份不存在或其文件已被移除。",
+                Status = StatusCodes.Status404NotFound
+            });
+        }
+    }
+
+    private async Task<IReadOnlyCollection<OperationalAlert>> BuildAlertsAsync(
+        OperationalHealthSnapshot health,
+        IReadOnlyCollection<BackupArtifact> backups,
+        int serverErrorCount,
+        int failedJobCount,
+        CancellationToken cancellationToken)
+    {
+        var alerts = health.Components
+            .Where(x => x.Status != "healthy")
+            .Select(x => new OperationalAlert(
+                $"health-{x.Key}",
+                x.Status == "unhealthy" ? "critical" : "warning",
+                "health",
+                $"{x.Label}状态异常",
+                x.Detail,
+                health.CheckedAt))
+            .ToList();
+
+        if (serverErrorCount > 0)
+        {
+            var latest = await db.AuditLogs.AsNoTracking()
+                .Where(x =>
+                    x.CreatedAt >= DateTime.UtcNow.AddHours(-24) &&
+                    x.StatusCode >= 500)
+                .OrderByDescending(x => x.CreatedAt)
+                .Select(x => new { x.Path, x.StatusCode, x.CreatedAt })
+                .FirstOrDefaultAsync(cancellationToken);
+            alerts.Add(new OperationalAlert(
+                "http-5xx",
+                "critical",
+                "audit",
+                $"过去 24 小时发生 {serverErrorCount} 次服务端错误",
+                latest is null
+                    ? "请检查服务日志定位异常。"
+                    : $"最近一次为 {latest.StatusCode} {latest.Path}。",
+                latest?.CreatedAt ?? DateTime.UtcNow));
+        }
+
+        if (failedJobCount > 0)
+        {
+            alerts.Add(new OperationalAlert(
+                "failed-jobs",
+                "critical",
+                "jobs",
+                $"最近 7 天有 {failedJobCount} 个后台任务失败",
+                "任务已停止或达到重试上限，请在失败任务中查看错误详情。",
+                DateTime.UtcNow));
+        }
+
+        var retryingFailures = await db.BackgroundJobOutboxMessages.AsNoTracking()
+            .CountAsync(
+                x => x.State != BackgroundJobOutboxState.Completed &&
+                     x.LastError != null,
+                cancellationToken);
+        if (retryingFailures > 0)
+        {
+            alerts.Add(new OperationalAlert(
+                "retrying-jobs",
+                "warning",
+                "jobs",
+                $"{retryingFailures} 个后台任务正在错误重试",
+                "任务队列仍会自动重试；若持续出现，请检查依赖服务与任务参数。",
+                DateTime.UtcNow));
+        }
+
+        var latestBackup = backups.FirstOrDefault();
+        if (latestBackup is null)
+        {
+            alerts.Add(new OperationalAlert(
+                "backup-missing",
+                "critical",
+                "backup",
+                "尚无可验证的数据库备份",
+                "立即创建首个备份，并在创建后执行一次隔离恢复演练。",
+                DateTime.UtcNow));
+        }
+        else
+        {
+            var ageHours = (DateTime.UtcNow - latestBackup.CreatedAt).TotalHours;
+            if (ageHours > options.BackupWarningHours)
+            {
+                alerts.Add(new OperationalAlert(
+                    "backup-stale",
+                    "warning",
+                    "backup",
+                    $"最近备份已超过 {options.BackupWarningHours} 小时",
+                    $"最近备份创建于 {latestBackup.CreatedAt:u}。",
+                    latestBackup.CreatedAt));
+            }
+            if (latestBackup.LastDrillSucceeded == false)
+            {
+                alerts.Add(new OperationalAlert(
+                    "restore-drill-failed",
+                    "critical",
+                    "backup",
+                    "最近一次恢复演练失败",
+                    latestBackup.LastDrillDetail ?? "请重新运行演练并检查数据库工具日志。",
+                    latestBackup.LastDrillAt ?? latestBackup.CreatedAt));
+            }
+            else if (!latestBackup.LastDrillAt.HasValue)
+            {
+                alerts.Add(new OperationalAlert(
+                    "restore-drill-missing",
+                    "warning",
+                    "backup",
+                    "最近备份尚未完成恢复演练",
+                    "恢复演练只写入隔离数据库，不会覆盖当前业务数据。",
+                    latestBackup.CreatedAt));
+            }
+        }
+
+        return alerts
+            .OrderBy(x => x.Severity == "critical" ? 0 : 1)
+            .ThenByDescending(x => x.OccurredAt)
+            .ToArray();
+    }
+
+    private async Task<int> CountFailedJobsAsync(
+        DateTime from,
+        CancellationToken cancellationToken) =>
+        await db.AutomaticScheduleJobs.AsNoTracking()
+            .CountAsync(
+                x => x.Status == AutomaticScheduleJobStatus.Failed &&
+                     x.CreatedAt >= from,
+                cancellationToken) +
+        await db.SchedulePublishJobs.AsNoTracking()
+            .CountAsync(
+                x => x.Status == SchedulePublishJobStatus.Failed &&
+                     x.CreatedAt >= from,
+                cancellationToken) +
+        await db.MakeupExamAutoJobs.AsNoTracking()
+            .CountAsync(
+                x => x.Status == MakeupExamAutoJobStatus.Failed &&
+                     x.CreatedAt >= from,
+                cancellationToken);
+
+    private ActionResult? ValidatePaging(int page, int pageSize)
+    {
+        if (page is < 1 or > 100000 || pageSize is < 1 or > 100)
+        {
+            return ValidationProblem(
+                "页码必须在 1 到 100000 之间，每页数量必须在 1 到 100 之间。");
+        }
+        return null;
+    }
+
+    private ActionResult? ValidateRange(DateTime? from, DateTime? to)
+    {
+        if (from.HasValue && to.HasValue && from.Value > to.Value)
+            return ValidationProblem("开始时间不能晚于结束时间。");
+        return null;
+    }
+
+    private static string? NormalizeJobKind(string? kind)
+    {
+        if (string.IsNullOrWhiteSpace(kind)) return null;
+        return kind.Trim() switch
+        {
+            "AutomaticSchedule" => "AutomaticSchedule",
+            "SchedulePublish" => "SchedulePublish",
+            "MakeupExamAuto" => "MakeupExamAuto",
+            _ => null
+        };
+    }
+
+    private static string SafeMessage(Exception exception)
+    {
+        var message = exception.GetBaseException().Message;
+        return message.Length <= 500 ? message : message[..500];
+    }
+}
+
+public sealed record AuditLogItem(
+    Guid Id,
+    string? UserName,
+    string Method,
+    string Path,
+    int StatusCode,
+    string? IpAddress,
+    DateTime CreatedAt);
+
+public sealed record FailedBackgroundJobItem(
+    Guid Id,
+    string Kind,
+    string KindLabel,
+    string Context,
+    string ErrorMessage,
+    DateTime CreatedAt,
+    DateTime? StartedAt,
+    DateTime? CompletedAt,
+    int ProcessingAttempts);
+
+public sealed record OperationalAlert(
+    string Id,
+    string Severity,
+    string Source,
+    string Title,
+    string Detail,
+    DateTime OccurredAt);
+
+public sealed record OperationsCounters(
+    int AuditEvents24Hours,
+    int ServerErrors24Hours,
+    int FailedJobs7Days,
+    int CriticalAlerts);
+
+public sealed record OperationsSummary(
+    DateTime GeneratedAt,
+    OperationalHealthSnapshot Health,
+    OperationsCounters Counters,
+    IReadOnlyCollection<OperationalAlert> Alerts,
+    BackupArtifact? LatestBackup);
+
+public sealed record CreateBackupRequest([MaxLength(200)] string? Note);
+
+public sealed record RestoreDrillRequest([Required] string Confirmation);

src/Jiaowu.Api/Domain/Academic/NotificationEntities.cs

@@ -44,5 +44,6 @@ public enum MessageAudienceType
 {
     School = 1,
     College = 2,
-    TeachingTask = 3
+    TeachingTask = 3,
+    Custom = 4
 }

src/Jiaowu.Api/Domain/Academic/PeopleAndCourseEntities.cs

@@ -50,6 +50,16 @@ public sealed class Course : CatalogEntity
     public CourseNature Nature { get; set; }
     public AssessmentMethod AssessmentMethod { get; set; }
     public string? Description { get; set; }
+    public ICollection<CoursePrerequisite> Prerequisites { get; set; } = [];
+    public ICollection<CoursePrerequisite> RequiredByCourses { get; set; } = [];
+}
+
+public sealed class CoursePrerequisite : EntityBase
+{
+    public Guid CourseId { get; set; }
+    public Course? Course { get; set; }
+    public Guid PrerequisiteCourseId { get; set; }
+    public Course? PrerequisiteCourse { get; set; }
 }
 
 public sealed class CourseCategory : CatalogEntity

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

@@ -26,6 +26,9 @@ public sealed class ExamArrangementService(AppDbContext db)
             .Include(x => x.Sessions)
                 .ThenInclude(x => x.TeachingTask)
                     .ThenInclude(x => x!.Teachers)
+            .Include(x => x.Sessions)
+                .ThenInclude(x => x.TeachingTask)
+                    .ThenInclude(x => x!.Course)
             .FirstOrDefaultAsync(x => x.Id == planId, cancellationToken);
 
         if (plan is null)

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

@@ -26,6 +26,9 @@ public sealed class MakeupExamArrangementService(AppDbContext db)
             .Include(x => x.Sessions)
                 .ThenInclude(x => x.TeachingTask)
                     .ThenInclude(x => x!.Teachers)
+            .Include(x => x.Sessions)
+                .ThenInclude(x => x.TeachingTask)
+                    .ThenInclude(x => x!.Course)
             .FirstOrDefaultAsync(x => x.Id == planId, cancellationToken);
 
         if (plan is null)

src/Jiaowu.Api/Infrastructure/Graduation/AcademicPlanningRules.cs

@@ -0,0 +1,115 @@
+using Jiaowu.Api.Domain.Academic;
+
+namespace Jiaowu.Api.Infrastructure.Graduation;
+
+public sealed record AcademicPlanningCourseSnapshot(
+    Guid CourseId,
+    string CourseName,
+    decimal Credits,
+    int RecommendedSemester,
+    CurriculumCourseType Type,
+    IReadOnlyCollection<Guid> PrerequisiteCourseIds);
+
+public sealed record AcademicPlanningPrerequisiteIssue(
+    Guid CourseId,
+    Guid PrerequisiteCourseId,
+    int PlannedSemester,
+    int? PrerequisitePlannedSemester);
+
+public static class AcademicPlanningRules
+{
+    public const decimal RecommendedSemesterCreditLimit = 24;
+    public const decimal HeavySemesterCreditLimit = 30;
+
+    public static IReadOnlyList<AcademicPlanningPrerequisiteIssue>
+        FindPrerequisiteIssues(
+            IEnumerable<AcademicPlanningCourseSnapshot> courses,
+            IReadOnlySet<Guid> completedCourseIds,
+            IReadOnlySet<Guid> inProgressCourseIds,
+            IReadOnlyDictionary<Guid, int> plannedSemesters)
+    {
+        var issues = new List<AcademicPlanningPrerequisiteIssue>();
+        foreach (var course in courses.Where(x =>
+                     plannedSemesters.ContainsKey(x.CourseId)))
+        {
+            var plannedSemester = plannedSemesters[course.CourseId];
+            foreach (var prerequisiteId in course.PrerequisiteCourseIds)
+            {
+                if (completedCourseIds.Contains(prerequisiteId) ||
+                    inProgressCourseIds.Contains(prerequisiteId))
+                    continue;
+
+                if (!plannedSemesters.TryGetValue(
+                        prerequisiteId,
+                        out var prerequisiteSemester) ||
+                    prerequisiteSemester >= plannedSemester)
+                {
+                    issues.Add(new AcademicPlanningPrerequisiteIssue(
+                        course.CourseId,
+                        prerequisiteId,
+                        plannedSemester,
+                        plannedSemesters.GetValueOrDefault(prerequisiteId)));
+                }
+            }
+        }
+        return issues;
+    }
+
+    public static IReadOnlyList<Guid> SuggestNextSemester(
+        IEnumerable<AcademicPlanningCourseSnapshot> courses,
+        IReadOnlySet<Guid> completedCourseIds,
+        IReadOnlySet<Guid> inProgressCourseIds,
+        int nextSemester,
+        decimal targetCredits = RecommendedSemesterCreditLimit)
+    {
+        var available = courses
+            .Where(x =>
+                !completedCourseIds.Contains(x.CourseId) &&
+                !inProgressCourseIds.Contains(x.CourseId) &&
+                x.RecommendedSemester <= nextSemester &&
+                x.PrerequisiteCourseIds.All(prerequisiteId =>
+                    completedCourseIds.Contains(prerequisiteId) ||
+                    inProgressCourseIds.Contains(prerequisiteId)))
+            .OrderBy(x => x.Type == CurriculumCourseType.Required ? 0 : 1)
+            .ThenBy(x => x.RecommendedSemester > nextSemester ? 1 : 0)
+            .ThenBy(x => x.RecommendedSemester)
+            .ThenBy(x => x.CourseName)
+            .ToList();
+
+        var selected = new List<Guid>();
+        decimal credits = 0;
+        foreach (var course in available)
+        {
+            var isOverdueRequired =
+                course.Type == CurriculumCourseType.Required &&
+                course.RecommendedSemester <= nextSemester;
+            if (!isOverdueRequired &&
+                selected.Count > 0 &&
+                credits + course.Credits > targetCredits)
+                continue;
+
+            selected.Add(course.CourseId);
+            credits += course.Credits;
+            if (credits >= targetCredits) break;
+        }
+        return selected;
+    }
+
+    public static int EstimateCompletionSemester(
+        int nextSemester,
+        int latestPlannedSemester,
+        decimal remainingCredits,
+        int remainingRequirementCount)
+    {
+        if (remainingCredits <= 0 && remainingRequirementCount <= 0)
+            return Math.Max(nextSemester - 1, latestPlannedSemester);
+
+        var byCredits = (int)Math.Ceiling(
+            Math.Max(remainingCredits, 0) / RecommendedSemesterCreditLimit);
+        var byRequirements = (int)Math.Ceiling(
+            Math.Max(remainingRequirementCount, 0) / 6m);
+        var additionalSemesters = Math.Max(1, Math.Max(byCredits, byRequirements));
+        return Math.Max(nextSemester - 1, latestPlannedSemester) +
+               additionalSemesters;
+    }
+}

src/Jiaowu.Api/Infrastructure/Operations/DatabaseBackupService.cs

@@ -0,0 +1,584 @@
+using System.Diagnostics;
+using System.Security.Cryptography;
+using System.Text.Json;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.Data.Sqlite;
+using MySql.Data.MySqlClient;
+
+namespace Jiaowu.Api.Infrastructure.Operations;
+
+public sealed record BackupArtifact(
+    string Id,
+    string FileName,
+    string Provider,
+    DateTime CreatedAt,
+    long SizeBytes,
+    string Sha256,
+    string? Note,
+    DateTime? LastDrillAt,
+    bool? LastDrillSucceeded,
+    string? LastDrillDetail,
+    long? LastDrillDurationMilliseconds);
+
+public sealed record RestoreDrillResult(
+    string BackupId,
+    bool Succeeded,
+    DateTime CompletedAt,
+    string Detail,
+    long DurationMilliseconds,
+    int? TableCount);
+
+public sealed class DatabaseBackupService(
+    DatabaseOptions databaseOptions,
+    OperationsOptions options,
+    IConfiguration configuration,
+    IHostEnvironment environment,
+    ILogger<DatabaseBackupService> logger)
+{
+    private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web)
+    {
+        WriteIndented = true
+    };
+
+    private readonly SemaphoreSlim operationLock = new(1, 1);
+    private readonly string backupDirectory = ResolveBackupDirectory(
+        options.BackupDirectory,
+        environment.ContentRootPath);
+
+    public async Task<IReadOnlyCollection<BackupArtifact>> ListAsync(
+        CancellationToken cancellationToken)
+    {
+        Directory.CreateDirectory(backupDirectory);
+        var items = new List<BackupArtifact>();
+        foreach (var metadataPath in Directory.EnumerateFiles(
+                     backupDirectory,
+                     "*.metadata.json",
+                     SearchOption.TopDirectoryOnly))
+        {
+            cancellationToken.ThrowIfCancellationRequested();
+            try
+            {
+                await using var stream = File.OpenRead(metadataPath);
+                var artifact = await JsonSerializer.DeserializeAsync<BackupArtifact>(
+                    stream,
+                    JsonOptions,
+                    cancellationToken);
+                if (artifact is not null &&
+                    File.Exists(Path.Combine(backupDirectory, artifact.FileName)))
+                {
+                    items.Add(artifact);
+                }
+            }
+            catch (Exception exception) when (
+                exception is IOException or UnauthorizedAccessException or JsonException)
+            {
+                logger.LogWarning(
+                    exception,
+                    "Unable to read backup metadata {MetadataFile}.",
+                    Path.GetFileName(metadataPath));
+            }
+        }
+
+        return items
+            .OrderByDescending(x => x.CreatedAt)
+            .ToArray();
+    }
+
+    public async Task<BackupArtifact> CreateAsync(
+        string? note,
+        CancellationToken cancellationToken)
+    {
+        await operationLock.WaitAsync(cancellationToken);
+        try
+        {
+            Directory.CreateDirectory(backupDirectory);
+            var createdAt = DateTime.UtcNow;
+            var id = $"{createdAt:yyyyMMddHHmmss}-{Guid.NewGuid():N}"[..29];
+            var provider = NormalizeProvider(databaseOptions.Provider);
+            var extension = provider == "SQLite" ? ".sqlite" : ".sql";
+            var fileName = $"jiaowu-{id}{extension}";
+            var backupPath = Path.Combine(backupDirectory, fileName);
+
+            try
+            {
+                if (provider == "SQLite")
+                    await CreateSqliteBackupAsync(backupPath, cancellationToken);
+                else
+                    await CreateMySqlBackupAsync(backupPath, cancellationToken);
+
+                var fileInfo = new FileInfo(backupPath);
+                var artifact = new BackupArtifact(
+                    id,
+                    fileName,
+                    provider,
+                    createdAt,
+                    fileInfo.Length,
+                    await ComputeHashAsync(backupPath, cancellationToken),
+                    NormalizeNote(note),
+                    null,
+                    null,
+                    null,
+                    null);
+                await WriteMetadataAsync(artifact, cancellationToken);
+                return artifact;
+            }
+            catch
+            {
+                if (File.Exists(backupPath))
+                    File.Delete(backupPath);
+                throw;
+            }
+        }
+        finally
+        {
+            operationLock.Release();
+        }
+    }
+
+    public async Task<RestoreDrillResult> RunRestoreDrillAsync(
+        string backupId,
+        CancellationToken cancellationToken)
+    {
+        await operationLock.WaitAsync(cancellationToken);
+        try
+        {
+            var artifact = (await ListAsync(cancellationToken))
+                .SingleOrDefault(x => x.Id.Equals(backupId, StringComparison.Ordinal));
+            if (artifact is null)
+                throw new FileNotFoundException("未找到指定备份。");
+
+            var backupPath = Path.Combine(backupDirectory, artifact.FileName);
+            var actualHash = await ComputeHashAsync(backupPath, cancellationToken);
+            if (!CryptographicOperations.FixedTimeEquals(
+                    Convert.FromHexString(artifact.Sha256),
+                    Convert.FromHexString(actualHash)))
+            {
+                var damaged = await CompleteDrillAsync(
+                    artifact,
+                    false,
+                    "备份文件校验和不一致，恢复演练已中止。",
+                    0,
+                    null,
+                    cancellationToken);
+                return damaged;
+            }
+
+            var stopwatch = Stopwatch.StartNew();
+            RestoreDrillResult result;
+            try
+            {
+                var tableCount = artifact.Provider == "SQLite"
+                    ? await DrillSqliteAsync(backupPath, cancellationToken)
+                    : await DrillMySqlAsync(backupPath, cancellationToken);
+                stopwatch.Stop();
+                result = await CompleteDrillAsync(
+                    artifact,
+                    true,
+                    $"已在隔离数据库完成恢复并通过完整性检查，共发现 {tableCount} 张业务表。",
+                    stopwatch.ElapsedMilliseconds,
+                    tableCount,
+                    cancellationToken);
+            }
+            catch (Exception exception) when (exception is not OperationCanceledException)
+            {
+                stopwatch.Stop();
+                logger.LogError(
+                    exception,
+                    "Restore drill failed for backup {BackupId}.",
+                    artifact.Id);
+                result = await CompleteDrillAsync(
+                    artifact,
+                    false,
+                    $"恢复演练失败：{SafeMessage(exception)}",
+                    stopwatch.ElapsedMilliseconds,
+                    null,
+                    cancellationToken);
+            }
+
+            return result;
+        }
+        finally
+        {
+            operationLock.Release();
+        }
+    }
+
+    private async Task CreateSqliteBackupAsync(
+        string backupPath,
+        CancellationToken cancellationToken)
+    {
+        var sourceBuilder = new SqliteConnectionStringBuilder(
+            configuration.GetConnectionString("SQLite")
+            ?? throw new InvalidOperationException("缺少 ConnectionStrings:SQLite。"));
+        if (!Path.IsPathRooted(sourceBuilder.DataSource))
+        {
+            sourceBuilder.DataSource = Path.GetFullPath(
+                sourceBuilder.DataSource,
+                environment.ContentRootPath);
+        }
+
+        var destinationBuilder = new SqliteConnectionStringBuilder
+        {
+            DataSource = backupPath,
+            Mode = SqliteOpenMode.ReadWriteCreate,
+            Pooling = false
+        };
+        await using var source = new SqliteConnection(sourceBuilder.ConnectionString);
+        await using var destination = new SqliteConnection(destinationBuilder.ConnectionString);
+        await source.OpenAsync(cancellationToken);
+        await destination.OpenAsync(cancellationToken);
+        source.BackupDatabase(destination);
+    }
+
+    private async Task CreateMySqlBackupAsync(
+        string backupPath,
+        CancellationToken cancellationToken)
+    {
+        var connection = GetMySqlConnectionBuilder();
+        var arguments = new List<string>
+        {
+            "--protocol=tcp",
+            $"--host={connection.Server}",
+            $"--port={connection.Port}",
+            $"--user={connection.UserID}",
+            "--single-transaction",
+            "--quick",
+            "--routines",
+            "--triggers",
+            "--events",
+            "--hex-blob",
+            "--default-character-set=utf8mb4"
+        };
+        arguments.AddRange(options.MySqlAdditionalArguments);
+        arguments.Add(connection.Database);
+
+        await using var output = new FileStream(
+            backupPath,
+            FileMode.CreateNew,
+            FileAccess.Write,
+            FileShare.None,
+            81920,
+            FileOptions.Asynchronous);
+        await RunToolAsync(
+            options.MySqlDumpPath,
+            arguments,
+            connection.Password,
+            standardInput: null,
+            standardOutput: output,
+            cancellationToken);
+    }
+
+    private static async Task<int> DrillSqliteAsync(
+        string backupPath,
+        CancellationToken cancellationToken)
+    {
+        var drillPath = Path.Combine(
+            Path.GetDirectoryName(backupPath)!,
+            $".restore-drill-{Guid.NewGuid():N}.sqlite");
+        try
+        {
+            var sourceBuilder = new SqliteConnectionStringBuilder
+            {
+                DataSource = backupPath,
+                Mode = SqliteOpenMode.ReadOnly,
+                Pooling = false
+            };
+            var drillBuilder = new SqliteConnectionStringBuilder
+            {
+                DataSource = drillPath,
+                Mode = SqliteOpenMode.ReadWriteCreate,
+                Pooling = false
+            };
+            await using var source = new SqliteConnection(sourceBuilder.ConnectionString);
+            await using var drill = new SqliteConnection(drillBuilder.ConnectionString);
+            await source.OpenAsync(cancellationToken);
+            await drill.OpenAsync(cancellationToken);
+            source.BackupDatabase(drill);
+
+            await using var integrity = drill.CreateCommand();
+            integrity.CommandText = "PRAGMA integrity_check;";
+            var integrityResult = Convert.ToString(
+                await integrity.ExecuteScalarAsync(cancellationToken));
+            if (!string.Equals(integrityResult, "ok", StringComparison.OrdinalIgnoreCase))
+                throw new InvalidDataException($"SQLite 完整性检查返回 {integrityResult ?? "空结果"}。");
+
+            await using var tables = drill.CreateCommand();
+            tables.CommandText =
+                "SELECT COUNT(*) FROM sqlite_master " +
+                "WHERE type = 'table' AND name NOT LIKE 'sqlite_%';";
+            return Convert.ToInt32(await tables.ExecuteScalarAsync(cancellationToken));
+        }
+        finally
+        {
+            if (File.Exists(drillPath))
+                File.Delete(drillPath);
+            if (File.Exists($"{drillPath}-shm"))
+                File.Delete($"{drillPath}-shm");
+            if (File.Exists($"{drillPath}-wal"))
+                File.Delete($"{drillPath}-wal");
+        }
+    }
+
+    private async Task<int> DrillMySqlAsync(
+        string backupPath,
+        CancellationToken cancellationToken)
+    {
+        var connection = GetMySqlConnectionBuilder();
+        var drillDatabase = $"jiaowu_restore_drill_{DateTime.UtcNow:yyyyMMddHHmmss}_" +
+                            Guid.NewGuid().ToString("N")[..8];
+        var adminBuilder = new MySqlConnectionStringBuilder(connection.ConnectionString)
+        {
+            Database = ""
+        };
+
+        await using var admin = new MySqlConnection(adminBuilder.ConnectionString);
+        await admin.OpenAsync(cancellationToken);
+        try
+        {
+            await using (var create = admin.CreateCommand())
+            {
+                create.CommandText =
+                    $"CREATE DATABASE `{drillDatabase}` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;";
+                await create.ExecuteNonQueryAsync(cancellationToken);
+            }
+
+            var arguments = new List<string>
+            {
+                "--protocol=tcp",
+                $"--host={connection.Server}",
+                $"--port={connection.Port}",
+                $"--user={connection.UserID}",
+                "--default-character-set=utf8mb4"
+            };
+            arguments.AddRange(options.MySqlAdditionalArguments);
+            arguments.Add($"--database={drillDatabase}");
+            await using (var input = new FileStream(
+                             backupPath,
+                             FileMode.Open,
+                             FileAccess.Read,
+                             FileShare.Read,
+                             81920,
+                             FileOptions.Asynchronous))
+            {
+                await RunToolAsync(
+                    options.MySqlClientPath,
+                    arguments,
+                    connection.Password,
+                    input,
+                    standardOutput: null,
+                    cancellationToken);
+            }
+
+            await using var count = admin.CreateCommand();
+            count.CommandText =
+                "SELECT COUNT(*) FROM information_schema.tables " +
+                "WHERE table_schema = @schema AND table_type = 'BASE TABLE';";
+            count.Parameters.AddWithValue("@schema", drillDatabase);
+            return Convert.ToInt32(await count.ExecuteScalarAsync(cancellationToken));
+        }
+        finally
+        {
+            try
+            {
+                await using var drop = admin.CreateCommand();
+                drop.CommandText = $"DROP DATABASE IF EXISTS `{drillDatabase}`;";
+                await drop.ExecuteNonQueryAsync(CancellationToken.None);
+            }
+            catch (Exception exception)
+            {
+                logger.LogCritical(
+                    exception,
+                    "Unable to remove isolated restore drill database {DatabaseName}.",
+                    drillDatabase);
+            }
+        }
+    }
+
+    private async Task RunToolAsync(
+        string executable,
+        IReadOnlyCollection<string> arguments,
+        string password,
+        Stream? standardInput,
+        Stream? standardOutput,
+        CancellationToken cancellationToken)
+    {
+        var startInfo = new ProcessStartInfo
+        {
+            FileName = executable,
+            UseShellExecute = false,
+            RedirectStandardError = true,
+            RedirectStandardInput = standardInput is not null,
+            RedirectStandardOutput = standardOutput is not null,
+            CreateNoWindow = true
+        };
+        foreach (var argument in arguments)
+            startInfo.ArgumentList.Add(argument);
+        if (!string.IsNullOrEmpty(password))
+            startInfo.Environment["MYSQL_PWD"] = password;
+
+        using var process = Process.Start(startInfo)
+            ?? throw new InvalidOperationException($"无法启动数据库工具 {executable}。");
+        using var timeout = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+        timeout.CancelAfter(TimeSpan.FromMinutes(options.ToolTimeoutMinutes));
+        var errorTask = process.StandardError.ReadToEndAsync(timeout.Token);
+        var inputTask = standardInput is null
+            ? Task.CompletedTask
+            : CopyInputAsync(standardInput, process.StandardInput.BaseStream, timeout.Token);
+        var outputTask = standardOutput is null
+            ? Task.CompletedTask
+            : process.StandardOutput.BaseStream.CopyToAsync(
+                standardOutput,
+                timeout.Token);
+
+        try
+        {
+            await Task.WhenAll(
+                process.WaitForExitAsync(timeout.Token),
+                inputTask,
+                outputTask);
+        }
+        catch (OperationCanceledException)
+        {
+            if (!process.HasExited)
+                process.Kill(entireProcessTree: true);
+            throw;
+        }
+
+        var error = await errorTask;
+        if (process.ExitCode != 0)
+            throw new InvalidOperationException(
+                $"数据库工具执行失败（退出码 {process.ExitCode}）：{TrimToolError(error)}");
+    }
+
+    private static async Task CopyInputAsync(
+        Stream input,
+        Stream processInput,
+        CancellationToken cancellationToken)
+    {
+        await input.CopyToAsync(processInput, cancellationToken);
+        await processInput.FlushAsync(cancellationToken);
+        processInput.Close();
+    }
+
+    private MySqlConnectionStringBuilder GetMySqlConnectionBuilder()
+    {
+        var value = configuration.GetConnectionString("OperationsMySql");
+        if (string.IsNullOrWhiteSpace(value))
+        {
+            throw new InvalidOperationException(
+                "MySQL 备份与恢复演练必须配置独立的 " +
+                "ConnectionStrings:OperationsMySql 运维账号，不能复用日常业务账号。");
+        }
+        var builder = new MySqlConnectionStringBuilder(value);
+        if (string.IsNullOrWhiteSpace(builder.Database))
+            throw new InvalidOperationException(
+                "OperationsMySql 连接字符串未指定业务数据库名称。");
+        return builder;
+    }
+
+    private async Task<RestoreDrillResult> CompleteDrillAsync(
+        BackupArtifact artifact,
+        bool succeeded,
+        string detail,
+        long durationMilliseconds,
+        int? tableCount,
+        CancellationToken cancellationToken)
+    {
+        var completedAt = DateTime.UtcNow;
+        var updated = artifact with
+        {
+            LastDrillAt = completedAt,
+            LastDrillSucceeded = succeeded,
+            LastDrillDetail = detail,
+            LastDrillDurationMilliseconds = durationMilliseconds
+        };
+        await WriteMetadataAsync(updated, cancellationToken);
+        return new RestoreDrillResult(
+            artifact.Id,
+            succeeded,
+            completedAt,
+            detail,
+            durationMilliseconds,
+            tableCount);
+    }
+
+    private async Task WriteMetadataAsync(
+        BackupArtifact artifact,
+        CancellationToken cancellationToken)
+    {
+        var metadataPath = Path.Combine(
+            backupDirectory,
+            $"{artifact.Id}.metadata.json");
+        var temporaryPath = $"{metadataPath}.{Guid.NewGuid():N}.tmp";
+        try
+        {
+            await using (var stream = new FileStream(
+                             temporaryPath,
+                             FileMode.CreateNew,
+                             FileAccess.Write,
+                             FileShare.None,
+                             16384,
+                             FileOptions.Asynchronous))
+            {
+                await JsonSerializer.SerializeAsync(
+                    stream,
+                    artifact,
+                    JsonOptions,
+                    cancellationToken);
+            }
+            File.Move(temporaryPath, metadataPath, overwrite: true);
+        }
+        finally
+        {
+            if (File.Exists(temporaryPath))
+                File.Delete(temporaryPath);
+        }
+    }
+
+    private static async Task<string> ComputeHashAsync(
+        string path,
+        CancellationToken cancellationToken)
+    {
+        await using var stream = File.OpenRead(path);
+        return Convert.ToHexString(
+            await SHA256.HashDataAsync(stream, cancellationToken));
+    }
+
+    private static string ResolveBackupDirectory(
+        string configuredPath,
+        string contentRoot)
+    {
+        if (string.IsNullOrWhiteSpace(configuredPath))
+            throw new InvalidOperationException("Operations:BackupDirectory 不能为空。");
+        return Path.IsPathRooted(configuredPath)
+            ? Path.GetFullPath(configuredPath)
+            : Path.GetFullPath(configuredPath, contentRoot);
+    }
+
+    private static string NormalizeProvider(string provider) =>
+        provider.Equals("SQLite", StringComparison.OrdinalIgnoreCase)
+            ? "SQLite"
+            : provider.Equals("MySql", StringComparison.OrdinalIgnoreCase)
+                ? "MySql"
+                : throw new InvalidOperationException($"不支持数据库 Provider '{provider}'。");
+
+    private static string? NormalizeNote(string? note)
+    {
+        if (string.IsNullOrWhiteSpace(note)) return null;
+        var trimmed = note.Trim();
+        return trimmed.Length <= 200 ? trimmed : trimmed[..200];
+    }
+
+    private static string SafeMessage(Exception exception)
+    {
+        var message = exception.GetBaseException().Message;
+        return message.Length <= 500 ? message : message[..500];
+    }
+
+    private static string TrimToolError(string error)
+    {
+        var trimmed = error.Trim();
+        if (trimmed.Length == 0) return "未返回错误详情。";
+        return trimmed.Length <= 500 ? trimmed : trimmed[..500];
+    }
+}

src/Jiaowu.Api/Infrastructure/Operations/OperationalHealthService.cs

@@ -0,0 +1,200 @@
+using System.Diagnostics;
+using Jiaowu.Api.Infrastructure.BackgroundJobs;
+using Jiaowu.Api.Infrastructure.Caching;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Caching.Distributed;
+
+namespace Jiaowu.Api.Infrastructure.Operations;
+
+public sealed record OperationalComponentHealth(
+    string Key,
+    string Label,
+    string Status,
+    string Backend,
+    long? LatencyMilliseconds,
+    string Detail);
+
+public sealed record OperationalHealthSnapshot(
+    DateTime CheckedAt,
+    string OverallStatus,
+    IReadOnlyCollection<OperationalComponentHealth> Components,
+    BackgroundJobBacklogSnapshot? Backlog);
+
+public sealed class OperationalHealthService(
+    AppDbContext db,
+    IServiceProvider services,
+    IBackgroundJobTransport transport,
+    BackgroundJobMonitoringService monitoring,
+    DatabaseOptions databaseOptions,
+    AppCacheOptions cacheOptions,
+    IConfiguration configuration)
+{
+    public async Task<OperationalHealthSnapshot> CheckAsync(
+        CancellationToken cancellationToken)
+    {
+        var database = await CheckDatabaseAsync(cancellationToken);
+        var cache = await CheckCacheAsync(cancellationToken);
+        var (messaging, backlog) = await CheckMessagingAsync(cancellationToken);
+        var components = new[] { database, cache, messaging };
+        var overall = components.Any(x => x.Status == "unhealthy")
+            ? "unhealthy"
+            : components.Any(x => x.Status == "warning")
+                ? "warning"
+                : "healthy";
+        return new OperationalHealthSnapshot(
+            DateTime.UtcNow,
+            overall,
+            components,
+            backlog);
+    }
+
+    private async Task<OperationalComponentHealth> CheckDatabaseAsync(
+        CancellationToken cancellationToken)
+    {
+        var stopwatch = Stopwatch.StartNew();
+        try
+        {
+            var canConnect = await db.Database.CanConnectAsync(cancellationToken);
+            stopwatch.Stop();
+            return canConnect
+                ? new OperationalComponentHealth(
+                    "database",
+                    "数据库",
+                    "healthy",
+                    databaseOptions.Provider,
+                    stopwatch.ElapsedMilliseconds,
+                    "连接与基础查询正常。")
+                : new OperationalComponentHealth(
+                    "database",
+                    "数据库",
+                    "unhealthy",
+                    databaseOptions.Provider,
+                    stopwatch.ElapsedMilliseconds,
+                    "无法建立数据库连接。");
+        }
+        catch (Exception exception) when (exception is not OperationCanceledException)
+        {
+            stopwatch.Stop();
+            return new OperationalComponentHealth(
+                "database",
+                "数据库",
+                "unhealthy",
+                databaseOptions.Provider,
+                stopwatch.ElapsedMilliseconds,
+                SafeMessage(exception));
+        }
+    }
+
+    private async Task<OperationalComponentHealth> CheckCacheAsync(
+        CancellationToken cancellationToken)
+    {
+        if (!cacheOptions.Enabled)
+        {
+            return new OperationalComponentHealth(
+                "cache",
+                "缓存",
+                "warning",
+                "disabled",
+                null,
+                "缓存已通过配置关闭，所有查询将直接访问数据源。");
+        }
+
+        var hasRedisConfiguration = !string.IsNullOrWhiteSpace(
+            configuration.GetConnectionString("Redis"));
+        var distributedCache = services.GetService<IDistributedCache>();
+        if (!hasRedisConfiguration || distributedCache is null)
+        {
+            return new OperationalComponentHealth(
+                "cache",
+                "缓存",
+                "healthy",
+                "memory",
+                null,
+                "使用进程内混合缓存；服务重启后缓存会自然重建。");
+        }
+
+        var stopwatch = Stopwatch.StartNew();
+        try
+        {
+            await distributedCache.GetAsync(
+                "jiaowu:operations:health-probe",
+                cancellationToken);
+            stopwatch.Stop();
+            return new OperationalComponentHealth(
+                "cache",
+                "缓存",
+                "healthy",
+                "redis",
+                stopwatch.ElapsedMilliseconds,
+                "Redis 连接与读取探针正常。");
+        }
+        catch (Exception exception) when (exception is not OperationCanceledException)
+        {
+            stopwatch.Stop();
+            return new OperationalComponentHealth(
+                "cache",
+                "缓存",
+                "unhealthy",
+                "redis",
+                stopwatch.ElapsedMilliseconds,
+                SafeMessage(exception));
+        }
+    }
+
+    private async Task<(OperationalComponentHealth Component,
+        BackgroundJobBacklogSnapshot? Backlog)> CheckMessagingAsync(
+        CancellationToken cancellationToken)
+    {
+        var stopwatch = Stopwatch.StartNew();
+        BackgroundJobBacklogSnapshot? backlog = null;
+        try
+        {
+            var healthy = await transport.CheckHealthAsync(cancellationToken);
+            backlog = await monitoring.GetSnapshotAsync(cancellationToken);
+            stopwatch.Stop();
+            var stuck = backlog.ExpiredLeases > 0 ||
+                        backlog.OldestUnfinishedAgeSeconds > 1800;
+            var status = !healthy
+                ? "unhealthy"
+                : stuck
+                    ? "warning"
+                    : "healthy";
+            var detail = !healthy
+                ? "后台任务传输不可用。"
+                : stuck
+                    ? $"发现 {backlog.ExpiredLeases} 个过期租约，最早未完成任务已等待 " +
+                      $"{Math.Round(backlog.OldestUnfinishedAgeSeconds ?? 0)} 秒。"
+                    : $"待发布 {backlog.Pending + backlog.Publishing}，" +
+                      $"待处理 {backlog.Published + backlog.Processing}。";
+            return (
+                new OperationalComponentHealth(
+                    "messaging",
+                    "后台任务通道",
+                    status,
+                    transport.IsDurable ? "rabbitmq" : "memory",
+                    stopwatch.ElapsedMilliseconds,
+                    detail),
+                backlog);
+        }
+        catch (Exception exception) when (exception is not OperationCanceledException)
+        {
+            stopwatch.Stop();
+            return (
+                new OperationalComponentHealth(
+                    "messaging",
+                    "后台任务通道",
+                    "unhealthy",
+                    transport.IsDurable ? "rabbitmq" : "memory",
+                    stopwatch.ElapsedMilliseconds,
+                    SafeMessage(exception)),
+                backlog);
+        }
+    }
+
+    private static string SafeMessage(Exception exception)
+    {
+        var message = exception.GetBaseException().Message;
+        return message.Length <= 300 ? message : message[..300];
+    }
+}

src/Jiaowu.Api/Infrastructure/Operations/OperationsOptions.cs

@@ -0,0 +1,13 @@
+namespace Jiaowu.Api.Infrastructure.Operations;
+
+public sealed class OperationsOptions
+{
+    public const string SectionName = "Operations";
+
+    public string BackupDirectory { get; set; } = "data/backups";
+    public int BackupWarningHours { get; set; } = 24;
+    public int ToolTimeoutMinutes { get; set; } = 30;
+    public string MySqlDumpPath { get; set; } = "mysqldump";
+    public string MySqlClientPath { get; set; } = "mysql";
+    public string[] MySqlAdditionalArguments { get; set; } = [];
+}

src/Jiaowu.Api/Infrastructure/Persistence/AppDbContext.cs

@@ -22,6 +22,7 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
     public DbSet<Student> Students => Set<Student>();
     public DbSet<CourseCategory> CourseCategories => Set<CourseCategory>();
     public DbSet<Course> Courses => Set<Course>();
+    public DbSet<CoursePrerequisite> CoursePrerequisites => Set<CoursePrerequisite>();
     public DbSet<CurriculumPlan> CurriculumPlans => Set<CurriculumPlan>();
     public DbSet<CurriculumModule> CurriculumModules => Set<CurriculumModule>();
     public DbSet<CurriculumCourse> CurriculumCourses => Set<CurriculumCourse>();
@@ -247,6 +248,20 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
                 .OnDelete(DeleteBehavior.Restrict);
         });
 
+        builder.Entity<CoursePrerequisite>(entity =>
+        {
+            entity.HasIndex(x => new { x.CourseId, x.PrerequisiteCourseId })
+                .IsUnique();
+            entity.HasOne(x => x.Course)
+                .WithMany(x => x.Prerequisites)
+                .HasForeignKey(x => x.CourseId)
+                .OnDelete(DeleteBehavior.Cascade);
+            entity.HasOne(x => x.PrerequisiteCourse)
+                .WithMany(x => x.RequiredByCourses)
+                .HasForeignKey(x => x.PrerequisiteCourseId)
+                .OnDelete(DeleteBehavior.Restrict);
+        });
+
         builder.Entity<CurriculumPlan>(entity =>
         {
             entity.Property(x => x.Name).HasMaxLength(120);
@@ -965,7 +980,7 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
         builder.Entity<Notification>(entity =>
         {
             entity.Property(x => x.Title).HasMaxLength(200);
-            entity.Property(x => x.Content).HasMaxLength(1000);
+            entity.Property(x => x.Content).HasColumnType("longtext");
             entity.Property(x => x.LinkUrl).HasMaxLength(300);
             entity.HasIndex(x => new { x.UserId, x.IsRead });
             entity.HasIndex(x => new { x.UserId, x.Category, x.CreatedAt });
@@ -981,7 +996,7 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
         {
             entity.Property(x => x.SenderName).HasMaxLength(100);
             entity.Property(x => x.Title).HasMaxLength(200);
-            entity.Property(x => x.Content).HasMaxLength(1000);
+            entity.Property(x => x.Content).HasColumnType("longtext");
             entity.Property(x => x.AudienceName).HasMaxLength(200);
             entity.Property(x => x.LinkUrl).HasMaxLength(300);
             entity.HasIndex(x => new { x.SenderUserId, x.CreatedAt });

src/Jiaowu.Api/Infrastructure/Persistence/DevelopmentSqliteMigrator.cs

@@ -62,6 +62,8 @@ public sealed class DevelopmentSqliteMigrator(
         "20260726_33_background_job_outbox";
     private const string CourseAdjustmentOccurrencesMigration =
         "20260727_34_course_adjustment_occurrences";
+    private const string AcademicPlanningPrerequisitesMigration =
+        "20260727_35_academic_planning_prerequisites";
 
     public async Task MigrateAsync(CancellationToken cancellationToken = default)
     {
@@ -453,6 +455,19 @@ public sealed class DevelopmentSqliteMigrator(
             BackgroundJobOutboxMigration,
             backgroundJobOutboxExists ? [] : BackgroundJobOutboxStatements,
             cancellationToken);
+
+        var coursePrerequisitesExist = await db.Database
+            .SqlQueryRaw<int>(
+                """
+                SELECT COUNT(*) AS "Value"
+                FROM sqlite_master
+                WHERE type = 'table' AND name = 'CoursePrerequisites'
+                """)
+            .AnyAsync(value => value > 0, cancellationToken);
+        await ApplyMigrationAsync(
+            AcademicPlanningPrerequisitesMigration,
+            coursePrerequisitesExist ? [] : AcademicPlanningPrerequisiteStatements,
+            cancellationToken);
     }
 
     private async Task ApplyMigrationAsync(
@@ -2090,4 +2105,31 @@ public sealed class DevelopmentSqliteMigrator(
         ON "BackgroundJobOutboxMessages" ("State", "CompletedAt");
         """
     ];
+
+    private static readonly string[] AcademicPlanningPrerequisiteStatements =
+    [
+        """
+        CREATE TABLE "CoursePrerequisites" (
+            "Id" TEXT NOT NULL CONSTRAINT "PK_CoursePrerequisites" PRIMARY KEY,
+            "CourseId" TEXT NOT NULL,
+            "PrerequisiteCourseId" TEXT NOT NULL,
+            "CreatedAt" TEXT NOT NULL,
+            "UpdatedAt" TEXT NOT NULL,
+            CONSTRAINT "FK_CoursePrerequisites_Courses_CourseId"
+                FOREIGN KEY ("CourseId") REFERENCES "Courses" ("Id")
+                ON DELETE CASCADE,
+            CONSTRAINT "FK_CoursePrerequisites_Courses_PrerequisiteCourseId"
+                FOREIGN KEY ("PrerequisiteCourseId") REFERENCES "Courses" ("Id")
+                ON DELETE RESTRICT
+        );
+        """,
+        """
+        CREATE UNIQUE INDEX "IX_CoursePrerequisites_CourseId_PrerequisiteCourseId"
+        ON "CoursePrerequisites" ("CourseId", "PrerequisiteCourseId");
+        """,
+        """
+        CREATE INDEX "IX_CoursePrerequisites_PrerequisiteCourseId"
+        ON "CoursePrerequisites" ("PrerequisiteCourseId");
+        """
+    ];
 }

src/Jiaowu.Api/Infrastructure/Persistence/Migrations/MySql/20260727034343_AcademicPlanningPrerequisites.cs

@@ -0,0 +1,61 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
+{
+    /// <inheritdoc />
+    public partial class AcademicPlanningPrerequisites : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "CoursePrerequisites",
+                columns: table => new
+                {
+                    Id = table.Column<Guid>(type: "char(36)", nullable: false),
+                    CourseId = table.Column<Guid>(type: "char(36)", nullable: false),
+                    PrerequisiteCourseId = table.Column<Guid>(type: "char(36)", nullable: false),
+                    CreatedAt = table.Column<DateTime>(type: "datetime(6)", nullable: false),
+                    UpdatedAt = table.Column<DateTime>(type: "datetime(6)", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_CoursePrerequisites", x => x.Id);
+                    table.ForeignKey(
+                        name: "FK_CoursePrerequisites_Courses_CourseId",
+                        column: x => x.CourseId,
+                        principalTable: "Courses",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "FK_CoursePrerequisites_Courses_PrerequisiteCourseId",
+                        column: x => x.PrerequisiteCourseId,
+                        principalTable: "Courses",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Restrict);
+                })
+                .Annotation("MySQL:Charset", "utf8mb4");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_CoursePrerequisites_CourseId_PrerequisiteCourseId",
+                table: "CoursePrerequisites",
+                columns: new[] { "CourseId", "PrerequisiteCourseId" },
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_CoursePrerequisites_PrerequisiteCourseId",
+                table: "CoursePrerequisites",
+                column: "PrerequisiteCourseId");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "CoursePrerequisites");
+        }
+    }
+}

src/Jiaowu.Api/Infrastructure/Persistence/Migrations/MySql/20260727043019_MessageRichContent.cs

@@ -0,0 +1,54 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
+{
+    /// <inheritdoc />
+    public partial class MessageRichContent : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterColumn<string>(
+                name: "Content",
+                table: "Notifications",
+                type: "longtext",
+                nullable: false,
+                oldClrType: typeof(string),
+                oldType: "varchar(1000)",
+                oldMaxLength: 1000);
+
+            migrationBuilder.AlterColumn<string>(
+                name: "Content",
+                table: "MessageDispatches",
+                type: "longtext",
+                nullable: false,
+                oldClrType: typeof(string),
+                oldType: "varchar(1000)",
+                oldMaxLength: 1000);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterColumn<string>(
+                name: "Content",
+                table: "Notifications",
+                type: "varchar(1000)",
+                maxLength: 1000,
+                nullable: false,
+                oldClrType: typeof(string),
+                oldType: "longtext");
+
+            migrationBuilder.AlterColumn<string>(
+                name: "Content",
+                table: "MessageDispatches",
+                type: "varchar(1000)",
+                maxLength: 1000,
+                nullable: false,
+                oldClrType: typeof(string),
+                oldType: "longtext");
+        }
+    }
+}

src/Jiaowu.Api/Infrastructure/Persistence/Migrations/MySql/AppDbContextModelSnapshot.cs

@@ -908,6 +908,34 @@ namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
                     b.ToTable("CourseExemptions");
                 });
 
+            modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CoursePrerequisite", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("char(36)");
+
+                    b.Property<Guid>("CourseId")
+                        .HasColumnType("char(36)");
+
+                    b.Property<DateTime>("CreatedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.Property<Guid>("PrerequisiteCourseId")
+                        .HasColumnType("char(36)");
+
+                    b.Property<DateTime>("UpdatedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("PrerequisiteCourseId");
+
+                    b.HasIndex("CourseId", "PrerequisiteCourseId")
+                        .IsUnique();
+
+                    b.ToTable("CoursePrerequisites");
+                });
+
             modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CourseSelectionOffering", b =>
                 {
                     b.Property<Guid>("Id")
@@ -2338,8 +2366,7 @@ namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
 
                     b.Property<string>("Content")
                         .IsRequired()
-                        .HasMaxLength(1000)
-                        .HasColumnType("varchar(1000)");
+                        .HasColumnType("longtext");
 
                     b.Property<DateTime>("CreatedAt")
                         .HasColumnType("datetime(6)");
@@ -2385,8 +2412,7 @@ namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
 
                     b.Property<string>("Content")
                         .IsRequired()
-                        .HasMaxLength(1000)
-                        .HasColumnType("varchar(1000)");
+                        .HasColumnType("longtext");
 
                     b.Property<DateTime>("CreatedAt")
                         .HasColumnType("datetime(6)");
@@ -3818,6 +3844,25 @@ namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
                     b.Navigation("TeachingTask");
                 });
 
+            modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CoursePrerequisite", b =>
+                {
+                    b.HasOne("Jiaowu.Api.Domain.Academic.Course", "Course")
+                        .WithMany("Prerequisites")
+                        .HasForeignKey("CourseId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.HasOne("Jiaowu.Api.Domain.Academic.Course", "PrerequisiteCourse")
+                        .WithMany("RequiredByCourses")
+                        .HasForeignKey("PrerequisiteCourseId")
+                        .OnDelete(DeleteBehavior.Restrict)
+                        .IsRequired();
+
+                    b.Navigation("Course");
+
+                    b.Navigation("PrerequisiteCourse");
+                });
+
             modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CourseSelectionOffering", b =>
                 {
                     b.HasOne("Jiaowu.Api.Domain.Academic.CourseSelectionRound", "CourseSelectionRound")
@@ -4734,6 +4779,13 @@ namespace Jiaowu.Api.Infrastructure.Persistence.Migrations.MySql
                     b.Navigation("Records");
                 });
 
+            modelBuilder.Entity("Jiaowu.Api.Domain.Academic.Course", b =>
+                {
+                    b.Navigation("Prerequisites");
+
+                    b.Navigation("RequiredByCourses");
+                });
+
             modelBuilder.Entity("Jiaowu.Api.Domain.Academic.CourseSelectionOffering", b =>
                 {
                     b.Navigation("Enrollments");

src/Jiaowu.Api/Program.cs

@@ -8,6 +8,7 @@ using Jiaowu.Api.Infrastructure.Caching;
 using Jiaowu.Api.Infrastructure.Exams;
 using Jiaowu.Api.Infrastructure.Middleware;
 using Jiaowu.Api.Infrastructure.OfficialDocuments;
+using Jiaowu.Api.Infrastructure.Operations;
 using Jiaowu.Api.Infrastructure.Persistence;
 using Jiaowu.Api.Infrastructure.Scheduling;
 using Jiaowu.Api.Infrastructure.Timetables;
@@ -74,6 +75,9 @@ var officialDocumentOptions = builder.Configuration
 var backgroundJobOptions = builder.Configuration
     .GetSection(BackgroundJobOptions.SectionName)
     .Get<BackgroundJobOptions>() ?? new BackgroundJobOptions();
+var operationsOptions = builder.Configuration
+    .GetSection(OperationsOptions.SectionName)
+    .Get<OperationsOptions>() ?? new OperationsOptions();
 var rabbitMqOptions = builder.Configuration
     .GetSection(RabbitMqOptions.SectionName)
     .Get<RabbitMqOptions>() ?? new RabbitMqOptions();
@@ -167,10 +171,25 @@ if (backgroundJobOptions.UsesRabbitMq &&
         "生产环境启用 RabbitMQ 时不能使用默认 guest 凭据。");
 }
 
+if (string.IsNullOrWhiteSpace(operationsOptions.BackupDirectory) ||
+    operationsOptions.BackupWarningHours is < 1 or > 8760 ||
+    operationsOptions.ToolTimeoutMinutes is < 1 or > 240 ||
+    string.IsNullOrWhiteSpace(operationsOptions.MySqlDumpPath) ||
+    string.IsNullOrWhiteSpace(operationsOptions.MySqlClientPath) ||
+    operationsOptions.MySqlAdditionalArguments.Length > 20 ||
+    operationsOptions.MySqlAdditionalArguments.Any(argument =>
+        string.IsNullOrWhiteSpace(argument) ||
+        argument.Length > 300 ||
+        !argument.StartsWith("--", StringComparison.Ordinal)))
+{
+    throw new InvalidOperationException("Operations 运维与备份配置超出允许范围。");
+}
+
 builder.Services.AddSingleton(databaseOptions);
 builder.Services.AddSingleton(cacheOptions);
 builder.Services.AddSingleton(officialDocumentOptions);
 builder.Services.AddSingleton(backgroundJobOptions);
+builder.Services.AddSingleton(operationsOptions);
 builder.Services.AddSingleton(rabbitMqOptions);
 builder.Services.Configure<OfficialDocumentOptions>(
     builder.Configuration.GetSection(OfficialDocumentOptions.SectionName));
@@ -277,6 +296,8 @@ builder.Services.AddScoped<MakeupExamArrangementService>();
 builder.Services.AddScoped<MakeupExamAutoJobProcessor>();
 builder.Services.AddSingleton<BackgroundJobTelemetry>();
 builder.Services.AddScoped<BackgroundJobMonitoringService>();
+builder.Services.AddScoped<OperationalHealthService>();
+builder.Services.AddSingleton<DatabaseBackupService>();
 builder.Services.AddSingleton<BackgroundJobRunner>();
 if (backgroundJobOptions.UsesRabbitMq)
 {

src/Jiaowu.Api/appsettings.json

@@ -19,6 +19,14 @@
     "AnalyticsLocalExpirationSeconds": 30,
     "MaximumPayloadKilobytes": 2048
   },
+  "Operations": {
+    "BackupDirectory": "data/backups",
+    "BackupWarningHours": 24,
+    "ToolTimeoutMinutes": 30,
+    "MySqlDumpPath": "mysqldump",
+    "MySqlClientPath": "mysql",
+    "MySqlAdditionalArguments": []
+  },
   "BackgroundJobs": {
     "Transport": "InMemory",
     "PollIntervalMilliseconds": 500,

tests/Jiaowu.Api.Tests/AcademicPlanningControllerTests.cs

@@ -0,0 +1,232 @@
+using System.Text.Json;
+using Jiaowu.Api.Controllers;
+using Jiaowu.Api.Domain.Academic;
+using Jiaowu.Api.Domain.Identity;
+using Jiaowu.Api.Infrastructure.Auth;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Data.Sqlite;
+using Microsoft.EntityFrameworkCore;
+
+namespace Jiaowu.Api.Tests;
+
+public sealed class AcademicPlanningControllerTests
+{
+    [Fact]
+    public async Task Simulation_reuses_published_grade_and_checks_prerequisites()
+    {
+        await using var connection = new SqliteConnection("Data Source=:memory:");
+        await connection.OpenAsync();
+        var options = new DbContextOptionsBuilder<AppDbContext>()
+            .UseSqlite(connection)
+            .Options;
+        await using var db = new AppDbContext(options);
+        await db.Database.EnsureCreatedAsync();
+
+        var user = new ApplicationUser
+        {
+            Id = Guid.NewGuid(),
+            UserName = "student",
+            NormalizedUserName = "STUDENT",
+            DisplayName = "规划学生"
+        };
+        var college = new College { Code = "CS", Name = "计算机学院" };
+        var major = new Major
+        {
+            Code = "SE",
+            Name = "软件工程",
+            CollegeId = college.Id,
+            DegreeType = "工学",
+            SchoolingYears = 4
+        };
+        var administrativeClass = new AdministrativeClass
+        {
+            Code = "SE2501",
+            Name = "软件工程2501班",
+            MajorId = major.Id,
+            Grade = 2025
+        };
+        var student = new Student
+        {
+            StudentNumber = "20250001",
+            Name = "规划学生",
+            AdministrativeClassId = administrativeClass.Id,
+            EnrollmentYear = 2025,
+            EnrollmentDate = new DateOnly(2025, 9, 1),
+            UserId = user.Id
+        };
+        var pastTerm = new AcademicTerm
+        {
+            Code = "2025-A",
+            Name = "2025—2026 学年秋季学期",
+            AcademicYear = "2025-2026",
+            Season = TermSeason.Autumn,
+            StartDate = new DateOnly(2025, 9, 1),
+            EndDate = new DateOnly(2026, 1, 15)
+        };
+        var currentTerm = new AcademicTerm
+        {
+            Code = "2025-S",
+            Name = "2025—2026 学年春季学期",
+            AcademicYear = "2025-2026",
+            Season = TermSeason.Spring,
+            StartDate = new DateOnly(2026, 2, 20),
+            EndDate = new DateOnly(2026, 7, 10),
+            IsCurrent = true
+        };
+        var introduction = new Course
+        {
+            Code = "CS101",
+            Name = "程序设计基础",
+            CollegeId = college.Id,
+            Credits = 4,
+            TotalHours = 64,
+            LectureHours = 48,
+            PracticeHours = 16,
+            Nature = CourseNature.MajorRequired,
+            AssessmentMethod = AssessmentMethod.Examination
+        };
+        var dataStructures = new Course
+        {
+            Code = "CS201",
+            Name = "数据结构",
+            CollegeId = college.Id,
+            Credits = 4,
+            TotalHours = 64,
+            LectureHours = 48,
+            PracticeHours = 16,
+            Nature = CourseNature.MajorRequired,
+            AssessmentMethod = AssessmentMethod.Examination,
+            Prerequisites =
+            [
+                new CoursePrerequisite
+                {
+                    PrerequisiteCourseId = introduction.Id
+                }
+            ]
+        };
+        var plan = new CurriculumPlan
+        {
+            MajorId = major.Id,
+            Name = "软件工程本科培养方案",
+            Version = "2025",
+            EffectiveGrade = 2025,
+            TotalCredits = 8,
+            Status = CurriculumPlanStatus.Published,
+            PublishedAt = DateTime.UtcNow,
+            Modules =
+            [
+                new CurriculumModule
+                {
+                    Code = "M01",
+                    Name = "专业基础",
+                    RequiredCredits = 0,
+                    Courses =
+                    [
+                        new CurriculumCourse
+                        {
+                            CourseId = introduction.Id,
+                            RecommendedSemester = 1,
+                            Type = CurriculumCourseType.Required
+                        },
+                        new CurriculumCourse
+                        {
+                            CourseId = dataStructures.Id,
+                            RecommendedSemester = 3,
+                            Type = CurriculumCourseType.Required
+                        }
+                    ]
+                }
+            ]
+        };
+        var teachingTask = new TeachingTask
+        {
+            TaskNumber = "2025-CS101-01",
+            Name = "程序设计基础",
+            AcademicTermId = pastTerm.Id,
+            CourseId = introduction.Id,
+            Capacity = 50,
+            Status = TeachingTaskStatus.Closed
+        };
+        var gradeSheet = new GradeSheet
+        {
+            TeachingTaskId = teachingTask.Id,
+            Status = GradeSheetStatus.Published,
+            PublishedAt = DateTime.UtcNow,
+            Records =
+            [
+                new GradeRecord
+                {
+                    StudentId = student.Id,
+                    TotalScore = 82,
+                    GradePoint = 3.2m
+                }
+            ]
+        };
+        db.AddRange(
+            user,
+            college,
+            major,
+            administrativeClass,
+            student,
+            pastTerm,
+            currentTerm,
+            introduction,
+            dataStructures,
+            plan,
+            teachingTask,
+            gradeSheet);
+        await db.SaveChangesAsync();
+
+        var controller = new AcademicPlanningController(
+            db,
+            new StudentDataScope(user.Id));
+        var overview = Assert.IsType<OkObjectResult>(
+            await controller.Get(default));
+        using var overviewJson = ToJson(overview.Value);
+        Assert.Equal(
+            4,
+            overviewJson.RootElement
+                .GetProperty("baseline")
+                .GetProperty("earnedCredits")
+                .GetDecimal());
+        Assert.Equal(
+            dataStructures.Id,
+            overviewJson.RootElement
+                .GetProperty("nextSemesterSuggestion")[0]
+                .GetProperty("courseId")
+                .GetGuid());
+
+        var result = Assert.IsType<OkObjectResult>(
+            await controller.Simulate(
+                new AcademicPlanningRequest(
+                [
+                    new AcademicPlanningTermRequest(
+                        3,
+                        [dataStructures.Id])
+                ]),
+                default));
+        using var resultJson = ToJson(result.Value);
+        Assert.Empty(resultJson.RootElement.GetProperty("conflicts").EnumerateArray());
+        var projected = resultJson.RootElement.GetProperty("projected");
+        Assert.Equal(8, projected.GetProperty("earnedCredits").GetDecimal());
+        Assert.Equal(
+            (int)GraduationAuditConclusion.Eligible,
+            projected.GetProperty("graduationConclusion").GetInt32());
+    }
+
+    private static JsonDocument ToJson(object? value) => JsonDocument.Parse(
+        JsonSerializer.Serialize(
+            value,
+            new JsonSerializerOptions(JsonSerializerDefaults.Web)));
+
+    private sealed class StudentDataScope(Guid userId) : ICurrentUserDataScope
+    {
+        public CurrentUserScope Current { get; } = new(
+            userId,
+            "规划学生",
+            null,
+            DataScope.Self,
+            new HashSet<string>([SystemRoles.Student]));
+    }
+}

tests/Jiaowu.Api.Tests/AcademicPlanningRulesTests.cs

@@ -0,0 +1,87 @@
+using Jiaowu.Api.Domain.Academic;
+using Jiaowu.Api.Infrastructure.Graduation;
+
+namespace Jiaowu.Api.Tests;
+
+public sealed class AcademicPlanningRulesTests
+{
+    private static readonly Guid AdvancedCourseId = Guid.NewGuid();
+    private static readonly Guid PrerequisiteCourseId = Guid.NewGuid();
+
+    private static readonly AcademicPlanningCourseSnapshot[] Courses =
+    [
+        new(
+            PrerequisiteCourseId,
+            "程序设计基础",
+            4,
+            1,
+            CurriculumCourseType.Required,
+            []),
+        new(
+            AdvancedCourseId,
+            "数据结构",
+            4,
+            2,
+            CurriculumCourseType.Required,
+            [PrerequisiteCourseId])
+    ];
+
+    [Fact]
+    public void Prerequisite_must_be_completed_or_planned_in_an_earlier_term()
+    {
+        var sameTerm = AcademicPlanningRules.FindPrerequisiteIssues(
+            Courses,
+            new HashSet<Guid>(),
+            new HashSet<Guid>(),
+            new Dictionary<Guid, int>
+            {
+                [PrerequisiteCourseId] = 3,
+                [AdvancedCourseId] = 3
+            });
+
+        var correctOrder = AcademicPlanningRules.FindPrerequisiteIssues(
+            Courses,
+            new HashSet<Guid>(),
+            new HashSet<Guid>(),
+            new Dictionary<Guid, int>
+            {
+                [PrerequisiteCourseId] = 3,
+                [AdvancedCourseId] = 4
+            });
+
+        Assert.Single(sameTerm);
+        Assert.Empty(correctOrder);
+    }
+
+    [Fact]
+    public void In_progress_prerequisite_unlocks_next_term_suggestion()
+    {
+        var suggestion = AcademicPlanningRules.SuggestNextSemester(
+            Courses,
+            new HashSet<Guid>(),
+            new HashSet<Guid>([PrerequisiteCourseId]),
+            2);
+
+        Assert.Equal([AdvancedCourseId], suggestion);
+    }
+
+    [Theory]
+    [InlineData(0, 0, 5, 4, 4)]
+    [InlineData(25, 0, 5, 4, 6)]
+    [InlineData(0, 7, 5, 4, 6)]
+    public void Completion_estimate_uses_credit_and_requirement_capacity(
+        decimal remainingCredits,
+        int remainingRequirements,
+        int nextSemester,
+        int latestPlannedSemester,
+        int expectedSemester)
+    {
+        Assert.Equal(
+            expectedSemester,
+            AcademicPlanningRules.EstimateCompletionSemester(
+                nextSemester,
+                latestPlannedSemester,
+                remainingCredits,
+                remainingRequirements));
+    }
+}

tests/Jiaowu.Api.Tests/DashboardControllerTests.cs

@@ -0,0 +1,261 @@
+using Jiaowu.Api.Controllers;
+using Jiaowu.Api.Domain.Academic;
+using Jiaowu.Api.Domain.Identity;
+using Jiaowu.Api.Infrastructure.Auth;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Data.Sqlite;
+using Microsoft.EntityFrameworkCore;
+
+namespace Jiaowu.Api.Tests;
+
+public sealed class DashboardControllerTests
+{
+    [Fact]
+    public async Task College_dashboard_is_scoped_and_only_counts_actionable_stage()
+    {
+        await using var database = await DashboardDatabase.CreateAsync();
+        var controller = new DashboardController(
+            database.Db,
+            new TestDataScope(
+                database.FirstCollegeId,
+                DataScope.College,
+                SystemRoles.CollegeAdmin));
+
+        var result = await controller.Get(CancellationToken.None);
+
+        var response = Assert.IsType<DashboardResponse>(
+            Assert.IsType<OkObjectResult>(result.Result).Value);
+        Assert.Equal("College", response.Audience.Level);
+        Assert.Equal("第一学院", response.Audience.ScopeName);
+        Assert.Equal(1, response.Counts.Students);
+        Assert.Equal(1, response.Counts.Teachers);
+        Assert.Equal(1, response.Counts.TeachingTasks);
+        Assert.Equal(1, response.Pending.TeacherApplications);
+        Assert.Equal(1, response.Pending.StudentStatusChanges);
+    }
+
+    [Fact]
+    public async Task School_dashboard_uses_school_stage_and_all_colleges()
+    {
+        await using var database = await DashboardDatabase.CreateAsync();
+        var controller = new DashboardController(
+            database.Db,
+            new TestDataScope(
+                null,
+                DataScope.All,
+                SystemRoles.AcademicAdmin));
+
+        var result = await controller.Get(CancellationToken.None);
+
+        var response = Assert.IsType<DashboardResponse>(
+            Assert.IsType<OkObjectResult>(result.Result).Value);
+        Assert.Equal("School", response.Audience.Level);
+        Assert.Equal(2, response.Counts.Students);
+        Assert.Equal(2, response.Counts.Teachers);
+        Assert.Equal(2, response.Counts.TeachingTasks);
+        Assert.Equal(2, response.Pending.TeacherApplications);
+        Assert.Equal(1, response.Pending.StudentStatusChanges);
+    }
+
+    private sealed class DashboardDatabase : IAsyncDisposable
+    {
+        private readonly SqliteConnection connection;
+
+        private DashboardDatabase(
+            SqliteConnection connection,
+            AppDbContext db,
+            Guid firstCollegeId)
+        {
+            this.connection = connection;
+            Db = db;
+            FirstCollegeId = firstCollegeId;
+        }
+
+        public AppDbContext Db { get; }
+        public Guid FirstCollegeId { get; }
+
+        public static async Task<DashboardDatabase> CreateAsync()
+        {
+            var connection = new SqliteConnection("Data Source=:memory:");
+            await connection.OpenAsync();
+            var options = new DbContextOptionsBuilder<AppDbContext>()
+                .UseSqlite(connection)
+                .Options;
+            var db = new AppDbContext(options);
+            await db.Database.EnsureCreatedAsync();
+
+            var term = new AcademicTerm
+            {
+                Code = "2026-1",
+                Name = "2026—2027 学年第一学期",
+                AcademicYear = "2026-2027",
+                Season = TermSeason.Autumn,
+                StartDate = new DateOnly(2026, 9, 1),
+                EndDate = new DateOnly(2027, 1, 15),
+                IsCurrent = true
+            };
+            var firstCollege = new College
+            {
+                Code = "C01",
+                Name = "第一学院"
+            };
+            var secondCollege = new College
+            {
+                Code = "C02",
+                Name = "第二学院"
+            };
+            var firstMajor = CreateMajor("M01", firstCollege);
+            var secondMajor = CreateMajor("M02", secondCollege);
+            var firstClass = CreateClass("CL01", firstMajor);
+            var secondClass = CreateClass("CL02", secondMajor);
+            var firstStudent = CreateStudent("S01", firstClass);
+            var secondStudent = CreateStudent("S02", secondClass);
+            var firstTeacher = CreateTeacher("T01", firstCollege);
+            var secondTeacher = CreateTeacher("T02", secondCollege);
+            var firstCourse = CreateCourse("COURSE01", firstCollege);
+            var secondCourse = CreateCourse("COURSE02", secondCollege);
+            var firstTask = CreateTask("TASK01", term, firstCourse);
+            var secondTask = CreateTask("TASK02", term, secondCourse);
+
+            db.AddRange(
+                term,
+                firstCollege,
+                secondCollege,
+                firstMajor,
+                secondMajor,
+                firstClass,
+                secondClass,
+                firstStudent,
+                secondStudent,
+                firstTeacher,
+                secondTeacher,
+                firstCourse,
+                secondCourse,
+                firstTask,
+                secondTask,
+                new TeacherCourseApplication
+                {
+                    AcademicTerm = term,
+                    Teacher = firstTeacher,
+                    Course = firstCourse,
+                    Status = TeacherCourseApplicationStatus.Pending
+                },
+                new TeacherCourseApplication
+                {
+                    AcademicTerm = term,
+                    Teacher = secondTeacher,
+                    Course = secondCourse,
+                    Status = TeacherCourseApplicationStatus.Pending
+                },
+                CreateStatusChange(
+                    firstStudent,
+                    StudentStatusChangeState.CounselorApproved),
+                CreateStatusChange(
+                    firstStudent,
+                    StudentStatusChangeState.CollegeApproved),
+                CreateStatusChange(
+                    secondStudent,
+                    StudentStatusChangeState.Submitted));
+            await db.SaveChangesAsync();
+
+            return new DashboardDatabase(connection, db, firstCollege.Id);
+        }
+
+        public async ValueTask DisposeAsync()
+        {
+            await Db.DisposeAsync();
+            await connection.DisposeAsync();
+        }
+
+        private static Major CreateMajor(string code, College college) => new()
+        {
+            Code = code,
+            Name = $"专业 {code}",
+            College = college,
+            DegreeType = "本科"
+        };
+
+        private static AdministrativeClass CreateClass(
+            string code,
+            Major major) => new()
+        {
+            Code = code,
+            Name = $"班级 {code}",
+            Major = major,
+            Grade = 2026
+        };
+
+        private static Student CreateStudent(
+            string number,
+            AdministrativeClass administrativeClass) => new()
+        {
+            StudentNumber = number,
+            Name = $"学生 {number}",
+            AdministrativeClass = administrativeClass,
+            EnrollmentYear = 2026,
+            EnrollmentDate = new DateOnly(2026, 9, 1),
+            Status = StudentStatus.Active
+        };
+
+        private static Teacher CreateTeacher(
+            string number,
+            College college) => new()
+        {
+            TeacherNumber = number,
+            Name = $"教师 {number}",
+            College = college,
+            Status = TeacherStatus.Active
+        };
+
+        private static Course CreateCourse(string code, College college) => new()
+        {
+            Code = code,
+            Name = $"课程 {code}",
+            College = college,
+            Nature = CourseNature.MajorRequired,
+            Credits = 2,
+            TotalHours = 32,
+            LectureHours = 32,
+            AssessmentMethod = AssessmentMethod.Examination
+        };
+
+        private static TeachingTask CreateTask(
+            string number,
+            AcademicTerm term,
+            Course course) => new()
+        {
+            TaskNumber = number,
+            Name = $"教学班 {number}",
+            AcademicTerm = term,
+            Course = course,
+            Capacity = 40,
+            Status = TeachingTaskStatus.Published
+        };
+
+        private static StudentStatusChange CreateStatusChange(
+            Student student,
+            StudentStatusChangeState state) => new()
+        {
+            Student = student,
+            Type = StudentStatusChangeType.Suspension,
+            OriginalStatus = StudentStatus.Active,
+            TargetStatus = StudentStatus.Suspended,
+            Reason = "测试学籍异动流程",
+            State = state
+        };
+    }
+
+    private sealed class TestDataScope(
+        Guid? collegeId,
+        DataScope dataScope,
+        string role) : ICurrentUserDataScope
+    {
+        public CurrentUserScope Current { get; } = new(
+            Guid.NewGuid(),
+            "测试管理员",
+            collegeId,
+            dataScope,
+            new HashSet<string> { role });
+    }
+}

tests/Jiaowu.Api.Tests/ExamArrangementServiceTests.cs

@@ -31,6 +31,7 @@ public sealed class ExamArrangementServiceTests
         plan.Sessions.Add(untouched);
         db.ExamPlans.Add(plan);
         await db.SaveChangesAsync();
+        db.ChangeTracker.Clear();
 
         var result = await new ExamArrangementService(db).ArrangeAsync(
             plan.Id,
@@ -39,11 +40,14 @@ public sealed class ExamArrangementServiceTests
             assignInvigilators: false,
             CancellationToken.None);
 
+        var persistedSelected = await db.ExamSessions.FindAsync(selected.Id);
+        var persistedUntouched = await db.ExamSessions.FindAsync(untouched.Id);
         Assert.True(result.Success);
-        Assert.NotNull(selected.ClassroomId);
-        Assert.Null(untouched.ClassroomId);
-        Assert.Empty(selected.Invigilators);
+        Assert.NotNull(persistedSelected!.ClassroomId);
+        Assert.Null(persistedUntouched!.ClassroomId);
+        Assert.Empty(persistedSelected.Invigilators);
         Assert.Contains("1个场次处理完成", result.Message);
+        Assert.Contains("程序设计", result.Message);
     }
 
     [Fact]
@@ -69,6 +73,7 @@ public sealed class ExamArrangementServiceTests
         plan.Sessions.Add(untouched);
         db.MakeupExamPlans.Add(plan);
         await db.SaveChangesAsync();
+        db.ChangeTracker.Clear();
 
         var result = await new MakeupExamArrangementService(db).ArrangeAsync(
             plan.Id,
@@ -77,11 +82,14 @@ public sealed class ExamArrangementServiceTests
             assignInvigilators: false,
             CancellationToken.None);
 
+        var persistedSelected = await db.MakeupExamSessions.FindAsync(selected.Id);
+        var persistedUntouched = await db.MakeupExamSessions.FindAsync(untouched.Id);
         Assert.True(result.Success);
-        Assert.NotNull(selected.ClassroomId);
-        Assert.Null(untouched.ClassroomId);
-        Assert.Empty(selected.Invigilators);
+        Assert.NotNull(persistedSelected!.ClassroomId);
+        Assert.Null(persistedUntouched!.ClassroomId);
+        Assert.Empty(persistedSelected.Invigilators);
         Assert.Contains("1个场次处理完成", result.Message);
+        Assert.Contains("程序设计", result.Message);
     }
 
     private static ExamSession NewExamSession(Guid planId, Guid taskId) => new()

tests/Jiaowu.Api.Tests/NotificationsControllerTests.cs

@@ -3,14 +3,50 @@ using Jiaowu.Api.Domain.Academic;
 using Jiaowu.Api.Domain.Identity;
 using Jiaowu.Api.Infrastructure.Auth;
 using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Abstractions;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+using Microsoft.AspNetCore.Mvc.ModelBinding.Validation;
+using Microsoft.AspNetCore.Routing;
 using Microsoft.Data.Sqlite;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
 
 namespace Jiaowu.Api.Tests;
 
 public sealed class NotificationsControllerTests
 {
+    [Fact]
+    public void Send_message_request_validation_metadata_is_compatible_with_mvc_record_binding()
+    {
+        var services = new ServiceCollection();
+        services.AddLogging();
+        services.AddControllers()
+            .AddApplicationPart(typeof(NotificationsController).Assembly);
+
+        using var serviceProvider = services.BuildServiceProvider();
+        var objectValidator = serviceProvider.GetRequiredService<IObjectModelValidator>();
+        var httpContext = new DefaultHttpContext
+        {
+            RequestServices = serviceProvider
+        };
+        var actionContext = new ActionContext(
+            httpContext,
+            new RouteData(),
+            new ActionDescriptor(),
+            new ModelStateDictionary());
+        var request = new SendMessageRequest(
+            "校内通知",
+            "<p>这是一条用于验证请求模型绑定的通知。</p>");
+
+        var exception = Record.Exception(() =>
+            objectValidator.Validate(actionContext, null, string.Empty, request));
+
+        Assert.Null(exception);
+        Assert.True(actionContext.ModelState.IsValid);
+    }
+
     [Fact]
     public async Task College_administrator_can_only_send_to_enabled_users_in_own_college()
     {
@@ -119,6 +155,85 @@ public sealed class NotificationsControllerTests
         Assert.Contains(fixture.ClassStudentUser.Id, recipientIds);
     }
 
+    [Fact]
+    public async Task School_administrator_can_filter_recipients_by_college()
+    {
+        await using var fixture = await NotificationFixture.CreateAsync();
+        var controller = new NotificationsController(
+            fixture.Db,
+            new TestDataScope(
+                fixture.Sender.Id,
+                fixture.FirstCollege.Id,
+                SystemRoles.AcademicAdmin));
+
+        var result = await controller.Send(
+            new SendMessageRequest(
+                "第二学院通知",
+                "<p><strong>仅发送</strong>给第二学院。</p>",
+                RecipientMode: MessageRecipientMode.Filtered,
+                RecipientFilter: new MessageRecipientFilter(
+                    CollegeId: fixture.SecondCollege.Id)),
+            CancellationToken.None);
+
+        Assert.IsType<OkObjectResult>(result);
+        var notification = Assert.Single(
+            await fixture.Db.Notifications.ToListAsync());
+        Assert.Equal(fixture.OutsideRecipient.Id, notification.UserId);
+        var dispatch = await fixture.Db.MessageDispatches.SingleAsync();
+        Assert.Equal(MessageAudienceType.Custom, dispatch.AudienceType);
+        Assert.Equal("指定学院", dispatch.AudienceName);
+    }
+
+    [Fact]
+    public async Task College_administrator_cannot_select_recipient_outside_college()
+    {
+        await using var fixture = await NotificationFixture.CreateAsync();
+        var controller = new NotificationsController(
+            fixture.Db,
+            new TestDataScope(
+                fixture.Sender.Id,
+                fixture.FirstCollege.Id,
+                SystemRoles.CollegeAdmin));
+
+        var result = await controller.Send(
+            new SendMessageRequest(
+                "越权消息",
+                "<p>不应发送。</p>",
+                RecipientMode: MessageRecipientMode.Selected,
+                RecipientUserIds: [fixture.OutsideRecipient.Id]),
+            CancellationToken.None);
+
+        Assert.IsType<BadRequestObjectResult>(result);
+        Assert.Empty(await fixture.Db.Notifications.ToListAsync());
+        Assert.Empty(await fixture.Db.MessageDispatches.ToListAsync());
+    }
+
+    [Fact]
+    public async Task Administrator_can_send_rich_content_larger_than_legacy_limit()
+    {
+        await using var fixture = await NotificationFixture.CreateAsync();
+        var controller = new NotificationsController(
+            fixture.Db,
+            new TestDataScope(
+                fixture.Sender.Id,
+                fixture.FirstCollege.Id,
+                SystemRoles.AcademicAdmin));
+        var content = $"<h2>教学安排</h2><p>{new string('内', 1500)}</p>";
+
+        var result = await controller.Send(
+            new SendMessageRequest(
+                "富文本通知",
+                content,
+                RecipientMode: MessageRecipientMode.Selected,
+                RecipientUserIds: [fixture.ClassStudentUser.Id]),
+            CancellationToken.None);
+
+        Assert.IsType<OkObjectResult>(result);
+        var notification = await fixture.Db.Notifications.SingleAsync();
+        Assert.Equal(content, notification.Content);
+        Assert.Equal(fixture.ClassStudentUser.Id, notification.UserId);
+    }
+
     [Fact]
     public async Task Publishing_course_grades_automatically_notifies_roster_students()
     {
@@ -189,6 +304,7 @@ public sealed class NotificationsControllerTests
             SqliteConnection connection,
             AppDbContext db,
             College firstCollege,
+            College secondCollege,
             ApplicationUser sender,
             ApplicationUser collegeRecipient,
             ApplicationUser outsideRecipient,
@@ -201,6 +317,7 @@ public sealed class NotificationsControllerTests
             this.connection = connection;
             Db = db;
             FirstCollege = firstCollege;
+            SecondCollege = secondCollege;
             Sender = sender;
             CollegeRecipient = collegeRecipient;
             OutsideRecipient = outsideRecipient;
@@ -213,6 +330,7 @@ public sealed class NotificationsControllerTests
 
         public AppDbContext Db { get; }
         public College FirstCollege { get; }
+        public College SecondCollege { get; }
         public ApplicationUser Sender { get; }
         public ApplicationUser CollegeRecipient { get; }
         public ApplicationUser OutsideRecipient { get; }
@@ -362,6 +480,7 @@ public sealed class NotificationsControllerTests
                 connection,
                 db,
                 firstCollege,
+                secondCollege,
                 sender,
                 collegeRecipient,
                 outsideRecipient,

tests/Jiaowu.Api.Tests/OperationsControllerTests.cs

@@ -0,0 +1,252 @@
+using System.Reflection;
+using Jiaowu.Api.Contracts;
+using Jiaowu.Api.Controllers;
+using Jiaowu.Api.Domain.Academic;
+using Jiaowu.Api.Domain.Identity;
+using Jiaowu.Api.Domain.System;
+using Jiaowu.Api.Infrastructure.BackgroundJobs;
+using Jiaowu.Api.Infrastructure.Caching;
+using Jiaowu.Api.Infrastructure.Operations;
+using Jiaowu.Api.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+
+namespace Jiaowu.Api.Tests;
+
+public sealed class OperationsControllerTests
+{
+    [Fact]
+    public void Controller_is_restricted_to_super_admin()
+    {
+        var authorize = typeof(OperationsController)
+            .GetCustomAttribute<AuthorizeAttribute>();
+
+        Assert.NotNull(authorize);
+        Assert.Equal(SystemRoles.SuperAdmin, authorize.Roles);
+    }
+
+    [Fact]
+    public async Task Audit_and_failed_job_queries_return_operational_records()
+    {
+        var root = CreateTemporaryRoot();
+        try
+        {
+            await using var fixture = await OperationsFixture.CreateAsync(root);
+            var term = new AcademicTerm
+            {
+                Code = "OPS-TERM",
+                Name = "运维测试学期",
+                AcademicYear = "2026-2027",
+                Season = TermSeason.Autumn,
+                StartDate = new DateOnly(2026, 9, 1),
+                EndDate = new DateOnly(2027, 1, 15)
+            };
+            var plan = new SchedulePlan
+            {
+                AcademicTerm = term,
+                Name = "恢复演练排课方案",
+                Version = "V1"
+            };
+            var job = new AutomaticScheduleJob
+            {
+                SchedulePlan = plan,
+                Status = AutomaticScheduleJobStatus.Failed,
+                ErrorMessage = "排课求解器未找到可行解。",
+                CompletedAt = DateTime.UtcNow
+            };
+            var outbox = BackgroundJobOutboxMessage.Create(
+                BackgroundJobKind.AutomaticSchedule,
+                job.Id);
+            outbox.State = BackgroundJobOutboxState.Completed;
+            outbox.ProcessingAttempts = 3;
+            fixture.Db.AuditLogs.Add(new AuditLog
+            {
+                UserName = "root",
+                Method = "POST",
+                Path = "/api/schedules",
+                StatusCode = 500,
+                IpAddress = "127.0.0.1"
+            });
+            fixture.Db.AddRange(term, plan, job, outbox);
+            await fixture.Db.SaveChangesAsync();
+
+            var auditAction = await fixture.Controller.GetAuditLogs(
+                cancellationToken: CancellationToken.None);
+            var auditResult = Assert.IsType<OkObjectResult>(auditAction.Result);
+            var auditPage = Assert.IsType<PagedResult<AuditLogItem>>(auditResult.Value);
+            Assert.Single(auditPage.Items);
+            Assert.Equal(500, auditPage.Items.Single().StatusCode);
+
+            var jobsAction = await fixture.Controller.GetFailedJobs(
+                cancellationToken: CancellationToken.None);
+            var jobsResult = Assert.IsType<OkObjectResult>(jobsAction.Result);
+            var jobsPage =
+                Assert.IsType<PagedResult<FailedBackgroundJobItem>>(jobsResult.Value);
+            var failed = Assert.Single(jobsPage.Items);
+            Assert.Equal("AutomaticSchedule", failed.Kind);
+            Assert.Equal(3, failed.ProcessingAttempts);
+            Assert.Contains("可行解", failed.ErrorMessage);
+        }
+        finally
+        {
+            DeleteTemporaryRoot(root);
+        }
+    }
+
+    [Fact]
+    public async Task Sqlite_backup_can_be_verified_in_an_isolated_restore_drill()
+    {
+        var root = CreateTemporaryRoot();
+        try
+        {
+            await using var fixture = await OperationsFixture.CreateAsync(root);
+            fixture.Db.AuditLogs.Add(new AuditLog
+            {
+                UserName = "backup-test",
+                Method = "POST",
+                Path = "/api/test",
+                StatusCode = 204
+            });
+            await fixture.Db.SaveChangesAsync();
+
+            var artifact = await fixture.Backups.CreateAsync(
+                "自动化测试",
+                CancellationToken.None);
+            var result = await fixture.Backups.RunRestoreDrillAsync(
+                artifact.Id,
+                CancellationToken.None);
+            var listed = await fixture.Backups.ListAsync(CancellationToken.None);
+
+            Assert.True(File.Exists(Path.Combine(
+                root,
+                "backups",
+                artifact.FileName)));
+            Assert.Equal(64, artifact.Sha256.Length);
+            Assert.True(result.Succeeded, result.Detail);
+            Assert.True(result.TableCount > 0);
+            Assert.True(Assert.Single(listed).LastDrillSucceeded);
+        }
+        finally
+        {
+            DeleteTemporaryRoot(root);
+        }
+    }
+
+    private static string CreateTemporaryRoot()
+    {
+        var root = Path.Combine(
+            Path.GetTempPath(),
+            $"jiaowu-operations-{Guid.NewGuid():N}");
+        Directory.CreateDirectory(root);
+        return root;
+    }
+
+    private static void DeleteTemporaryRoot(string root)
+    {
+        var resolved = Path.GetFullPath(root);
+        var temporary = Path.GetFullPath(Path.GetTempPath());
+        Assert.StartsWith(temporary, resolved, StringComparison.OrdinalIgnoreCase);
+        if (Directory.Exists(resolved))
+            Directory.Delete(resolved, recursive: true);
+    }
+
+    private sealed class OperationsFixture : IAsyncDisposable
+    {
+        private readonly ServiceProvider provider;
+
+        private OperationsFixture(
+            ServiceProvider provider,
+            AppDbContext db,
+            OperationsController controller,
+            DatabaseBackupService backups)
+        {
+            this.provider = provider;
+            Db = db;
+            Controller = controller;
+            Backups = backups;
+        }
+
+        public AppDbContext Db { get; }
+        public OperationsController Controller { get; }
+        public DatabaseBackupService Backups { get; }
+
+        public static async Task<OperationsFixture> CreateAsync(string root)
+        {
+            var databasePath = Path.Combine(root, "source.sqlite");
+            var configuration = new ConfigurationBuilder()
+                .AddInMemoryCollection(new Dictionary<string, string?>
+                {
+                    ["ConnectionStrings:SQLite"] =
+                        $"Data Source={databasePath};Pooling=False"
+                })
+                .Build();
+            var databaseOptions = new DatabaseOptions { Provider = "SQLite" };
+            var cacheOptions = new AppCacheOptions();
+            var operationsOptions = new OperationsOptions
+            {
+                BackupDirectory = "backups"
+            };
+            var dbContextOptions = new DbContextOptionsBuilder<AppDbContext>()
+                .UseSqlite(configuration.GetConnectionString("SQLite"))
+                .Options;
+            var db = new AppDbContext(dbContextOptions);
+            await db.Database.EnsureCreatedAsync();
+
+            var services = new ServiceCollection()
+                .AddLogging()
+                .BuildServiceProvider();
+            var logger = services.GetRequiredService<
+                ILogger<DatabaseBackupService>>();
+            var environment = new TestHostEnvironment
+            {
+                ContentRootPath = root
+            };
+            var transport = new InMemoryBackgroundJobTransport();
+            var monitoring = new BackgroundJobMonitoringService(db);
+            var health = new OperationalHealthService(
+                db,
+                services,
+                transport,
+                monitoring,
+                databaseOptions,
+                cacheOptions,
+                configuration);
+            var backups = new DatabaseBackupService(
+                databaseOptions,
+                operationsOptions,
+                configuration,
+                environment,
+                logger);
+            var controller = new OperationsController(
+                db,
+                health,
+                backups,
+                operationsOptions);
+            return new OperationsFixture(services, db, controller, backups);
+        }
+
+        public async ValueTask DisposeAsync()
+        {
+            await Db.DisposeAsync();
+            await provider.DisposeAsync();
+        }
+    }
+
+    private sealed class TestHostEnvironment : IWebHostEnvironment
+    {
+        public string ApplicationName { get; set; } = "Jiaowu.Api.Tests";
+        public IFileProvider WebRootFileProvider { get; set; } = new NullFileProvider();
+        public string WebRootPath { get; set; } = "";
+        public string EnvironmentName { get; set; } = Environments.Development;
+        public string ContentRootPath { get; set; } = "";
+        public IFileProvider ContentRootFileProvider { get; set; } =
+            new NullFileProvider();
+    }
+}

web/.env.example

@@ -1 +1,3 @@
 VITE_API_BASE_URL=/api
+# 自托管 CKEditor 5：GPL 兼容项目可保留 GPL；商业部署请在构建时填写正式许可证键。
+VITE_CKEDITOR_LICENSE_KEY=GPL

web/package.json

@@ -9,8 +9,11 @@
     "preview": "vite preview"
   },
   "dependencies": {
+    "@ckeditor/ckeditor5-vue": "^8.2.0",
     "@element-plus/icons-vue": "^2.3.2",
     "axios": "^1.18.1",
+    "ckeditor5": "^48.3.1",
+    "dompurify": "^3.4.12",
     "echarts": "^6.1.0",
     "element-plus": "^2.14.3",
     "html2canvas": "^1.4.1",

web/src/components.d.ts

@@ -38,6 +38,7 @@ declare module 'vue' {
     ElProgress: typeof import('element-plus/es')['ElProgress']
     ElRadioButton: typeof import('element-plus/es')['ElRadioButton']
     ElRadioGroup: typeof import('element-plus/es')['ElRadioGroup']
+    ElResult: typeof import('element-plus/es')['ElResult']
     ElSegmented: typeof import('element-plus/es')['ElSegmented']
     ElSelect: typeof import('element-plus/es')['ElSelect']
     ElSlider: typeof import('element-plus/es')['ElSlider']
@@ -49,6 +50,7 @@ declare module 'vue' {
     ElTabs: typeof import('element-plus/es')['ElTabs']
     ElTag: typeof import('element-plus/es')['ElTag']
     ElTimeSelect: typeof import('element-plus/es')['ElTimeSelect']
+    RichMessageContent: typeof import('./components/RichMessageContent.vue')['default']
     RouterLink: typeof import('vue-router')['RouterLink']
     RouterView: typeof import('vue-router')['RouterView']
   }

web/src/components/RichMessageContent.vue

@@ -0,0 +1,165 @@
+<script setup lang="ts">
+import { computed } from 'vue'
+import DOMPurify from 'dompurify'
+
+const props = defineProps<{
+  content: string
+  rich?: boolean
+}>()
+
+const safeHtml = computed(() => DOMPurify.sanitize(props.content, {
+  ALLOWED_TAGS: [
+    'p', 'br', 'strong', 'b', 'em', 'i', 'u', 's',
+    'h2', 'h3', 'h4', 'ul', 'ol', 'li', 'blockquote', 'a',
+    'figure', 'figcaption', 'img',
+    'table', 'thead', 'tbody', 'tfoot', 'tr', 'th', 'td', 'colgroup', 'col',
+  ],
+  ALLOWED_ATTR: [
+    'href', 'target', 'rel',
+    'src', 'alt', 'title', 'width', 'height', 'class', 'style',
+    'colspan', 'rowspan', 'scope',
+  ],
+  ALLOW_DATA_ATTR: false,
+}))
+</script>
+
+<template>
+  <div v-if="rich" class="rich-message-content" v-html="safeHtml" />
+  <p v-else class="plain-message-content">{{ content }}</p>
+</template>
+
+<style scoped>
+.plain-message-content {
+  margin: 0;
+  white-space: pre-wrap;
+}
+
+.rich-message-content {
+  overflow-wrap: anywhere;
+  color: inherit;
+  font-size: inherit;
+  line-height: 1.75;
+}
+
+.rich-message-content::after {
+  display: block;
+  clear: both;
+  content: '';
+}
+
+.rich-message-content :deep(p),
+.rich-message-content :deep(ul),
+.rich-message-content :deep(ol),
+.rich-message-content :deep(blockquote) {
+  margin: 0 0 .65em;
+}
+
+.rich-message-content :deep(p:last-child),
+.rich-message-content :deep(ul:last-child),
+.rich-message-content :deep(ol:last-child),
+.rich-message-content :deep(blockquote:last-child) {
+  margin-bottom: 0;
+}
+
+.rich-message-content :deep(h2),
+.rich-message-content :deep(h3),
+.rich-message-content :deep(h4) {
+  margin: .8em 0 .35em;
+  color: var(--ink);
+  font-family: inherit;
+}
+
+.rich-message-content :deep(h2) { font-size: 1.25em; }
+.rich-message-content :deep(h3) { font-size: 1.12em; }
+.rich-message-content :deep(h4) { font-size: 1em; }
+
+.rich-message-content :deep(ul),
+.rich-message-content :deep(ol) {
+  padding-left: 1.5em;
+}
+
+.rich-message-content :deep(blockquote) {
+  padding: .55em .9em;
+  border-left: 3px solid var(--teal);
+  background: #f3f8f7;
+}
+
+.rich-message-content :deep(a) {
+  color: var(--indigo);
+  text-decoration: underline;
+  text-underline-offset: 2px;
+}
+
+.rich-message-content :deep(figure) {
+  margin: .9em auto;
+}
+
+.rich-message-content :deep(figure.image) {
+  max-width: 100%;
+}
+
+.rich-message-content :deep(img) {
+  display: block;
+  max-width: 100%;
+  height: auto;
+  margin: 0 auto;
+  border-radius: 6px;
+}
+
+.rich-message-content :deep(figcaption) {
+  margin-top: .4em;
+  color: var(--muted);
+  font-size: .86em;
+  line-height: 1.5;
+  text-align: center;
+}
+
+.rich-message-content :deep(.image-style-align-left),
+.rich-message-content :deep(.image-style-block-align-left) {
+  margin-right: 1.25em;
+  margin-left: 0;
+}
+
+.rich-message-content :deep(.image-style-align-right),
+.rich-message-content :deep(.image-style-block-align-right),
+.rich-message-content :deep(.image-style-side) {
+  margin-right: 0;
+  margin-left: auto;
+}
+
+.rich-message-content :deep(.image-style-wrap-text.image-style-align-left) {
+  float: left;
+}
+
+.rich-message-content :deep(.image-style-wrap-text.image-style-align-right),
+.rich-message-content :deep(.image-style-side) {
+  float: right;
+  margin-left: 1.25em;
+}
+
+.rich-message-content :deep(figure.table) {
+  max-width: 100%;
+  overflow-x: auto;
+}
+
+.rich-message-content :deep(table) {
+  width: 100%;
+  border-collapse: collapse;
+  background: #fff;
+}
+
+.rich-message-content :deep(th),
+.rich-message-content :deep(td) {
+  min-width: 4.5em;
+  padding: .55em .7em;
+  border: 1px solid var(--line);
+  vertical-align: top;
+}
+
+.rich-message-content :deep(th) {
+  background: #f3f5f8;
+  color: var(--ink);
+  font-weight: 650;
+  text-align: left;
+}
+</style>

web/src/layouts/AdminLayout.vue

@@ -97,6 +97,7 @@ const navigationGroups = computed<NavigationGroup[]>(() => [
         { path: '/students', label: '学生档案' },
       ),
       ...whenVisible(auth.isSuperAdmin, { path: '/users', label: '用户与权限' }),
+      ...whenVisible(auth.isSuperAdmin, { path: '/operations', label: '运维与审计' }),
     ],
   },
   {
@@ -205,6 +206,10 @@ const navigationGroups = computed<NavigationGroup[]>(() => [
     key: 'graduation',
     label: '毕业管理',
     items: [
+      ...whenVisible(
+        isStudent.value,
+        { path: '/academic-planning', label: '学业规划与毕业模拟' },
+      ),
       ...whenVisible(
         hasAnyRole(['SuperAdmin', 'AcademicAdmin', 'CollegeAdmin', 'Student']),
         { path: '/graduation-audits', label: isStudent.value ? '毕业资格' : '毕业审核' },

web/src/router/index.ts

@@ -118,6 +118,12 @@ const router = createRouter({
           component: () => import('../views/StudentCurriculumView.vue'),
           meta: { roles: ['Student'] },
         },
+        {
+          path: 'academic-planning',
+          name: 'academic-planning',
+          component: () => import('../views/AcademicPlanningView.vue'),
+          meta: { roles: ['Student'] },
+        },
         {
           path: 'teaching-tasks',
           name: 'teaching-tasks',
@@ -285,6 +291,12 @@ const router = createRouter({
           component: () => import('../views/UsersView.vue'),
           meta: { roles: ['SuperAdmin'] },
         },
+        {
+          path: 'operations',
+          name: 'operations',
+          component: () => import('../views/OperationsConsoleView.vue'),
+          meta: { roles: ['SuperAdmin'] },
+        },
         {
           path: 'evaluations',
           name: 'evaluations',

web/src/views/AcademicPlanningView.vue

@@ -0,0 +1,815 @@
+<script setup lang="ts">
+import { computed, onBeforeUnmount, onMounted, ref, watch } from 'vue'
+import { Delete, MagicStick, Refresh, Search } from '@element-plus/icons-vue'
+import http, { apiErrorMessage } from '../api/http'
+
+interface PlanningTerm {
+  semester: number
+  label: string
+  isBeyondStandard: boolean
+  courseIds: string[]
+}
+
+const loading = ref(false)
+const simulationLoading = ref(false)
+const initialized = ref(false)
+const payload = ref<any>(null)
+const simulation = ref<any>(null)
+const terms = ref<PlanningTerm[]>([])
+const keyword = ref('')
+const moduleFilter = ref('')
+let simulationTimer: ReturnType<typeof setTimeout> | undefined
+
+const courses = computed<any[]>(() => payload.value?.courses ?? [])
+const baseline = computed(() => payload.value?.baseline ?? {})
+const projected = computed(() => simulation.value?.projected ?? {
+  earnedCredits: baseline.value.earnedCredits ?? 0,
+  planCompletedCredits: baseline.value.planCompletedCredits ?? 0,
+  creditGap: baseline.value.creditGap ?? 0,
+  completionRate: baseline.value.completionRate ?? 0,
+  requirementCount: baseline.value.requirementCount ?? 0,
+  passedRequirementCount: baseline.value.passedRequirementCount ?? 0,
+  missingRequirements: baseline.value.missingRequirements ?? [],
+  graduationConclusion: 'Ineligible',
+  estimatedGraduationTerm: '等待模拟',
+  isBeyondStandard: false,
+})
+const modules = computed(() =>
+  [...new Map(courses.value.map((course) =>
+    [course.moduleCode, { code: course.moduleCode, name: course.moduleName }],
+  )).values()],
+)
+const assigned = computed(() => {
+  const result = new Map<string, number>()
+  for (const term of terms.value) {
+    for (const courseId of term.courseIds) result.set(courseId, term.semester)
+  }
+  return result
+})
+const remainingCourses = computed(() => {
+  const normalized = keyword.value.trim().toLowerCase()
+  return courses.value.filter((course) => {
+    if (['Completed', 'InProgress', 'Retaking'].includes(course.status)) return false
+    if (moduleFilter.value && course.moduleCode !== moduleFilter.value) return false
+    return !normalized ||
+      `${course.courseCode} ${course.courseName} ${course.moduleName}`
+        .toLowerCase()
+        .includes(normalized)
+  })
+})
+const plannedCourseCount = computed(() =>
+  terms.value.reduce((count, term) => count + term.courseIds.length, 0),
+)
+const plannedCredits = computed(() =>
+  courses.value
+    .filter((course) => assigned.value.has(course.courseId))
+    .reduce((sum, course) => sum + Number(course.credits), 0),
+)
+const conflictCourseIds = computed(() =>
+  new Set<string>((simulation.value?.conflicts ?? []).map((item: any) => item.courseId)),
+)
+const termSummaryMap = computed(() =>
+  new Map<number, any>((simulation.value?.termSummaries ?? [])
+    .map((item: any) => [item.semester, item])),
+)
+
+function courseById(courseId: string) {
+  return courses.value.find((course) => course.courseId === courseId)
+}
+
+function typeLabel(type: string) {
+  return type === 'Required' ? '指定必修' : '组内选修'
+}
+
+function setCourseSemester(courseId: string, semester?: number) {
+  for (const term of terms.value) {
+    term.courseIds = term.courseIds.filter((id) => id !== courseId)
+  }
+  if (semester) {
+    const target = terms.value.find((term) => term.semester === semester)
+    if (target) target.courseIds.push(courseId)
+  }
+}
+
+function removeCourse(courseId: string) {
+  setCourseSemester(courseId)
+}
+
+function applySuggestion() {
+  const target = terms.value.find(
+    (term) => term.semester === payload.value?.plan?.nextSemester,
+  )
+  if (!target) return
+  const ids = (payload.value?.nextSemesterSuggestion ?? [])
+    .map((course: any) => course.courseId)
+    .filter((courseId: string) => !assigned.value.has(courseId))
+  target.courseIds.push(...ids)
+  ElMessage.success(`已把 ${ids.length} 门建议课程安排到下一学期`)
+}
+
+function clearPlan() {
+  for (const term of terms.value) term.courseIds = []
+}
+
+async function simulate() {
+  simulationLoading.value = true
+  try {
+    simulation.value = (await http.post('/student/academic-planning/simulate', {
+      terms: terms.value.map((term) => ({
+        semester: term.semester,
+        courseIds: term.courseIds,
+      })),
+    })).data
+  } catch (error) {
+    ElMessage.error(apiErrorMessage(error))
+  } finally {
+    simulationLoading.value = false
+  }
+}
+
+function scheduleSimulation() {
+  if (!initialized.value) return
+  if (simulationTimer) clearTimeout(simulationTimer)
+  simulationTimer = setTimeout(simulate, 180)
+}
+
+async function load() {
+  loading.value = true
+  initialized.value = false
+  try {
+    payload.value = (await http.get('/student/academic-planning')).data
+    terms.value = payload.value.terms.map((term: any) => ({
+      ...term,
+      courseIds: [],
+    }))
+    initialized.value = true
+    await simulate()
+  } catch (error) {
+    ElMessage.error(apiErrorMessage(error))
+  } finally {
+    loading.value = false
+  }
+}
+
+watch(terms, scheduleSimulation, { deep: true })
+onMounted(load)
+onBeforeUnmount(() => {
+  if (simulationTimer) clearTimeout(simulationTimer)
+})
+</script>
+
+<template>
+  <div class="page-stack academic-planning-page" v-loading="loading">
+    <section class="page-intro">
+      <div>
+        <span class="section-kicker">DEGREE FLIGHT PLAN</span>
+        <h2>学业规划与毕业模拟</h2>
+        <p>把未来课程排进学期航线，实时检查培养方案完成度、先修顺序与毕业时间。</p>
+      </div>
+      <div class="page-actions">
+        <el-button :icon="Refresh" @click="load">重置数据</el-button>
+        <el-button
+          type="primary"
+          :icon="MagicStick"
+          :disabled="!payload?.nextSemesterSuggestion?.length"
+          @click="applySuggestion"
+        >
+          采用下学期建议
+        </el-button>
+      </div>
+    </section>
+
+    <template v-if="payload">
+      <section class="planning-cockpit">
+        <div class="student-call-sign">
+          <span>{{ payload.student.enrollmentYear }} 级 · {{ payload.student.collegeName }}</span>
+          <h3>{{ payload.student.name }}的毕业航线</h3>
+          <p>{{ payload.student.studentNumber }} · {{ payload.student.majorName }} · {{ payload.plan.name }} {{ payload.plan.version }}</p>
+        </div>
+        <div class="completion-dial" aria-label="模拟培养方案完成度">
+          <span>方案完成度</span>
+          <b>{{ projected.completionRate }}<small>%</small></b>
+          <i><em :style="{ width: `${projected.completionRate}%` }" /></i>
+        </div>
+        <div class="arrival-board">
+          <span>预计毕业</span>
+          <b>{{ projected.estimatedGraduationTerm }}</b>
+          <small :class="{ delayed: projected.isBeyondStandard }">
+            {{ projected.isBeyondStandard ? '超过标准学制' : '标准学制内' }}
+          </small>
+        </div>
+      </section>
+
+      <section class="planning-metrics" aria-label="毕业模拟摘要">
+        <div>
+          <span>已获 / 预计学分</span>
+          <b>{{ baseline.earnedCredits }} <small>→</small> {{ projected.earnedCredits }}</b>
+        </div>
+        <div :class="{ alert: projected.creditGap > 0 }">
+          <span>毕业学分缺口</span>
+          <b>{{ projected.creditGap }}<small> 学分</small></b>
+        </div>
+        <div>
+          <span>培养要求</span>
+          <b>{{ projected.passedRequirementCount }}<small> / {{ projected.requirementCount }} 项</small></b>
+        </div>
+        <div>
+          <span>本次模拟</span>
+          <b>{{ plannedCourseCount }}<small> 门 · {{ plannedCredits }} 学分</small></b>
+        </div>
+      </section>
+
+      <section class="next-term-brief">
+        <header>
+          <span>NEXT TERM ADVICE</span>
+          <h3>下一学期建议</h3>
+          <p>{{ payload.terms[0]?.label }}</p>
+        </header>
+        <div v-if="payload.nextSemesterSuggestion.length" class="suggestion-list">
+          <article
+            v-for="course in payload.nextSemesterSuggestion"
+            :key="course.courseId"
+          >
+            <div>
+              <span>{{ course.courseCode }} · {{ typeLabel(course.type) }}</span>
+              <b>{{ course.courseName }}</b>
+            </div>
+            <small>{{ course.credits }} 学分</small>
+            <p>{{ course.reason }}</p>
+          </article>
+        </div>
+        <p v-else class="no-suggestion">
+          结合当前在读课程、先修条件和培养方案建议学期，下一学期暂无需要额外安排的课程；仍可在下方课程清单模拟其他路径。
+        </p>
+      </section>
+
+      <section
+        v-if="payload.latestGraduationAudit"
+        class="official-audit-strip"
+      >
+        <div>
+          <span>最近正式毕业审核</span>
+          <b>{{ payload.latestGraduationAudit.batchName }}</b>
+          <small>{{ payload.latestGraduationAudit.publishedAt?.slice(0, 10) }}</small>
+        </div>
+        <p>
+          正式结果：{{ payload.latestGraduationAudit.conclusion === 'Eligible' ? '符合毕业条件' : '暂不符合毕业条件' }}
+          · 已认定 {{ payload.latestGraduationAudit.earnedCredits }} 学分
+        </p>
+        <em>模拟不会更改正式审核结果</em>
+      </section>
+
+      <section
+        v-if="simulation?.conflicts?.length || simulation?.warnings?.length"
+        class="planning-alerts"
+      >
+        <article v-for="item in simulation.conflicts" :key="`${item.type}-${item.courseId}-${item.prerequisiteCourseId}`">
+          <span>先修冲突</span>
+          <p>{{ item.message }}</p>
+        </article>
+        <article v-for="(item, index) in simulation.warnings" :key="`${item.type}-${index}`" class="warning">
+          <span>安排提示</span>
+          <p>{{ item.message }}</p>
+        </article>
+      </section>
+
+      <section class="planner-workspace">
+        <aside class="course-pool">
+          <header>
+            <div>
+              <span>COURSE MANIFEST</span>
+              <h3>待规划课程</h3>
+            </div>
+            <b>{{ remainingCourses.length }}</b>
+          </header>
+          <div class="pool-filters">
+            <el-input
+              v-model="keyword"
+              :prefix-icon="Search"
+              clearable
+              placeholder="搜索课程"
+            />
+            <el-select v-model="moduleFilter" clearable placeholder="全部培养模块">
+              <el-option
+                v-for="module in modules"
+                :key="module.code"
+                :label="module.name"
+                :value="module.code"
+              />
+            </el-select>
+          </div>
+          <div class="pool-list">
+            <article
+              v-for="course in remainingCourses"
+              :key="course.courseId"
+              :class="{
+                assigned: assigned.has(course.courseId),
+                conflicted: conflictCourseIds.has(course.courseId),
+              }"
+            >
+              <div class="course-manifest-line">
+                <span>{{ course.courseCode }} · {{ course.moduleName }}</span>
+                <i>{{ course.credits }} 学分</i>
+              </div>
+              <h4>{{ course.courseName }}</h4>
+              <div class="course-flags">
+                <span>{{ typeLabel(course.type) }}</span>
+                <span>建议第 {{ course.recommendedSemester }} 学期</span>
+                <span v-if="course.status === 'Failed'" class="failed">有未通过记录</span>
+              </div>
+              <p v-if="course.prerequisites.length">
+                先修：
+                <template v-for="(item, index) in course.prerequisites" :key="item.courseId">
+                  <b :class="{ ready: item.isCompleted || item.isInProgress }">{{ item.courseName }}</b>{{ Number(index) < course.prerequisites.length - 1 ? '、' : '' }}
+                </template>
+              </p>
+              <el-select
+                :model-value="assigned.get(course.courseId)"
+                clearable
+                placeholder="安排到学期"
+                @change="setCourseSemester(course.courseId, $event)"
+              >
+                <el-option
+                  v-for="term in terms"
+                  :key="term.semester"
+                  :label="`第 ${term.semester} 学期 · ${term.label}`"
+                  :value="term.semester"
+                />
+              </el-select>
+            </article>
+            <el-empty v-if="!remainingCourses.length" description="没有符合条件的待规划课程" />
+          </div>
+        </aside>
+
+        <main class="semester-runway" v-loading="simulationLoading">
+          <header>
+            <div>
+              <span>SEMESTER RUNWAY</span>
+              <h3>未来学期航线</h3>
+              <p>课程必须在其先修课程之后；单学期超过 30 学分会标记负荷风险。</p>
+            </div>
+            <el-button text :icon="Delete" @click="clearPlan">清空安排</el-button>
+          </header>
+
+          <div class="runway-line">
+            <article
+              v-for="term in terms"
+              :key="term.semester"
+              class="semester-stop"
+              :class="{ beyond: term.isBeyondStandard }"
+            >
+              <div class="semester-marker">
+                <i>{{ term.semester }}</i>
+                <span>{{ term.isBeyondStandard ? '延长学期' : `第 ${term.semester} 学期` }}</span>
+              </div>
+              <div class="semester-sheet">
+                <header>
+                  <div>
+                    <span>{{ term.label }}</span>
+                    <h4>{{ term.semester === payload.plan.nextSemester ? '下一学期' : `未来第 ${term.semester - payload.plan.currentSemester} 学期` }}</h4>
+                  </div>
+                  <b>
+                    {{ termSummaryMap.get(term.semester)?.credits ?? 0 }}
+                    <small>学分</small>
+                  </b>
+                </header>
+                <div v-if="term.courseIds.length" class="scheduled-courses">
+                  <article
+                    v-for="courseId in term.courseIds"
+                    :key="courseId"
+                    :class="{ conflicted: conflictCourseIds.has(courseId) }"
+                  >
+                    <div>
+                      <span>{{ courseById(courseId)?.courseCode }} · {{ typeLabel(courseById(courseId)?.type) }}</span>
+                      <b>{{ courseById(courseId)?.courseName }}</b>
+                    </div>
+                    <small>{{ courseById(courseId)?.credits }} 学分</small>
+                    <el-button
+                      text
+                      type="danger"
+                      aria-label="移除课程"
+                      @click="removeCourse(courseId)"
+                    >×</el-button>
+                  </article>
+                </div>
+                <p v-else class="empty-semester">尚未安排课程，可从左侧课程清单选择学期。</p>
+              </div>
+            </article>
+            <div class="graduation-gate" :class="{ ready: projected.graduationConclusion === 'Eligible' }">
+              <span>GRADUATION GATE</span>
+              <b>{{ projected.graduationConclusion === 'Eligible' ? '模拟达到毕业条件' : '仍有培养要求未完成' }}</b>
+              <p>{{ projected.estimatedGraduationTerm }}</p>
+            </div>
+          </div>
+        </main>
+      </section>
+
+      <section class="planning-closeout">
+        <div>
+          <span>剩余培养要求</span>
+          <h3>{{ projected.missingRequirements?.length ? `还需完成 ${projected.missingRequirements.length} 项` : '培养要求已覆盖' }}</h3>
+        </div>
+        <div class="missing-requirements">
+          <span v-for="item in projected.missingRequirements" :key="item">{{ item }}</span>
+          <em v-if="!projected.missingRequirements?.length">本次模拟已覆盖全部指定课程和课程组要求</em>
+        </div>
+        <ul>
+          <li v-for="item in payload.assumptions" :key="item">{{ item }}</li>
+        </ul>
+      </section>
+    </template>
+  </div>
+</template>
+
+<style scoped>
+.planning-cockpit {
+  min-height: 154px;
+  display: grid;
+  grid-template-columns: minmax(300px, 1.2fr) minmax(230px, .7fr) minmax(280px, .9fr);
+  color: white;
+  border: 1px solid #15275b;
+  background:
+    linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px),
+    linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px),
+    linear-gradient(112deg, #142557, #253e78 63%, #0c6f70);
+  background-size: 26px 26px, 26px 26px, auto;
+}
+.student-call-sign,
+.completion-dial,
+.arrival-board { padding: 26px 28px; }
+.student-call-sign > span,
+.completion-dial > span,
+.arrival-board > span,
+.course-pool header span,
+.semester-runway > header span {
+  color: #69d8c7;
+  font: 700 9px/1.2 Consolas, monospace;
+  letter-spacing: .12em;
+}
+.student-call-sign h3 {
+  margin: 10px 0 7px;
+  font-family: "STZhongsong", "Songti SC", serif;
+  font-size: 25px;
+  letter-spacing: .04em;
+}
+.student-call-sign p { margin: 0; color: #c8d1e6; font-size: 10px; }
+.completion-dial,
+.arrival-board {
+  border-left: 1px solid rgba(255,255,255,.16);
+}
+.completion-dial b {
+  display: block;
+  margin: 12px 0 11px;
+  font: 700 34px/1 Consolas, monospace;
+}
+.completion-dial b small { font-size: 13px; }
+.completion-dial i {
+  display: block;
+  height: 6px;
+  background: rgba(255,255,255,.17);
+}
+.completion-dial em {
+  display: block;
+  height: 100%;
+  background: #5fe0c8;
+  transition: width .2s ease;
+}
+.arrival-board b {
+  display: block;
+  margin: 14px 0 10px;
+  font-family: "STZhongsong", "Songti SC", serif;
+  font-size: 16px;
+  line-height: 1.45;
+}
+.arrival-board small {
+  padding-left: 8px;
+  color: #76e1cf;
+  border-left: 3px solid #5fe0c8;
+  font-size: 10px;
+}
+.arrival-board small.delayed { color: #ffd48a; border-color: #e8a840; }
+.planning-metrics {
+  display: grid;
+  grid-template-columns: repeat(4, 1fr);
+  border: 1px solid var(--line);
+  background: white;
+}
+.planning-metrics > div {
+  min-height: 80px;
+  padding: 15px 19px;
+  display: grid;
+  align-content: center;
+  border-right: 1px solid var(--line);
+  box-shadow: inset 0 3px #23827a;
+}
+.planning-metrics > div:last-child { border-right: 0; }
+.planning-metrics > div.alert { box-shadow: inset 0 3px #bd5a4f; }
+.planning-metrics span { color: var(--muted); font-size: 9px; }
+.planning-metrics b {
+  margin-top: 8px;
+  color: var(--ink);
+  font: 700 21px/1 Consolas, monospace;
+}
+.planning-metrics small { color: var(--muted); font-size: 9px; }
+.next-term-brief {
+  min-height: 74px;
+  padding: 13px 16px;
+  display: grid;
+  grid-template-columns: 180px 1fr;
+  gap: 18px;
+  align-items: center;
+  border: 1px solid #cfd8e5;
+  background: #f7f9fc;
+}
+.next-term-brief > header span {
+  color: var(--teal);
+  font: 700 9px/1.2 Consolas, monospace;
+  letter-spacing: .1em;
+}
+.next-term-brief > header h3 { margin: 5px 0 3px; font-size: 14px; }
+.next-term-brief > header p,
+.no-suggestion { margin: 0; color: var(--muted); font-size: 9px; line-height: 1.6; }
+.suggestion-list { display: flex; flex-wrap: wrap; gap: 7px; }
+.suggestion-list article {
+  min-width: 220px;
+  padding: 9px 11px;
+  display: grid;
+  grid-template-columns: 1fr auto;
+  gap: 4px 12px;
+  border-left: 3px solid #168377;
+  background: white;
+}
+.suggestion-list span { color: var(--teal); font-size: 8px; }
+.suggestion-list b { display: block; margin-top: 3px; font-size: 10px; }
+.suggestion-list small { color: var(--indigo); font: 700 10px/1.2 Consolas, monospace; }
+.suggestion-list p {
+  grid-column: 1 / -1;
+  margin: 0;
+  color: var(--muted);
+  font-size: 8px;
+}
+.official-audit-strip {
+  min-height: 58px;
+  padding: 10px 16px;
+  display: grid;
+  grid-template-columns: minmax(220px, .8fr) 1fr auto;
+  gap: 22px;
+  align-items: center;
+  border: 1px solid #cdd6e5;
+  background: #f5f8fc;
+}
+.official-audit-strip div { display: grid; gap: 3px; }
+.official-audit-strip span { color: var(--teal); font-size: 9px; font-weight: 700; }
+.official-audit-strip b { font-size: 11px; }
+.official-audit-strip small,
+.official-audit-strip p { margin: 0; color: var(--muted); font-size: 9px; }
+.official-audit-strip em {
+  padding: 5px 8px;
+  color: #52617a;
+  border: 1px solid #cdd5e1;
+  font-size: 9px;
+  font-style: normal;
+}
+.planning-alerts {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 8px;
+}
+.planning-alerts article {
+  min-height: 55px;
+  padding: 10px 13px;
+  display: grid;
+  grid-template-columns: 74px 1fr;
+  gap: 10px;
+  align-items: center;
+  border: 1px solid #e2b9b5;
+  background: #fff7f6;
+}
+.planning-alerts article.warning { border-color: #e4cca0; background: #fffaf0; }
+.planning-alerts span { color: #a4423b; font-size: 9px; font-weight: 700; }
+.planning-alerts .warning span { color: #9b6417; }
+.planning-alerts p { margin: 0; color: #5d4b4b; font-size: 10px; line-height: 1.5; }
+.planner-workspace {
+  display: grid;
+  grid-template-columns: minmax(310px, 360px) minmax(0, 1fr);
+  gap: 14px;
+  align-items: start;
+}
+.course-pool,
+.semester-runway {
+  border: 1px solid var(--line);
+  background: white;
+}
+.course-pool {
+  position: sticky;
+  top: 14px;
+}
+.course-pool > header,
+.semester-runway > header {
+  min-height: 72px;
+  padding: 15px 17px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  border-bottom: 1px solid var(--line);
+  background: #f7f9fc;
+}
+.course-pool h3,
+.semester-runway h3 { margin: 5px 0 0; font-size: 15px; }
+.course-pool > header b {
+  color: var(--indigo);
+  font: 700 25px/1 Consolas, monospace;
+}
+.pool-filters {
+  padding: 11px;
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 8px;
+  border-bottom: 1px solid var(--line);
+}
+.pool-list {
+  max-height: 680px;
+  overflow: auto;
+}
+.pool-list > article {
+  padding: 14px;
+  border-bottom: 1px solid #e8ebf0;
+  box-shadow: inset 3px 0 #8d97aa;
+  transition: background .15s ease, box-shadow .15s ease;
+}
+.pool-list > article.assigned { background: #f1f8f7; box-shadow: inset 3px 0 #0d8175; }
+.pool-list > article.conflicted { background: #fff6f5; box-shadow: inset 3px 0 #b64b43; }
+.course-manifest-line {
+  display: flex;
+  justify-content: space-between;
+  gap: 8px;
+}
+.course-manifest-line span { color: var(--teal); font: 700 9px/1.2 Consolas, monospace; }
+.course-manifest-line i { color: var(--muted); font-size: 9px; font-style: normal; }
+.pool-list h4 { margin: 7px 0; font-size: 13px; }
+.course-flags { display: flex; flex-wrap: wrap; gap: 5px; }
+.course-flags span {
+  padding: 3px 5px;
+  color: #58657a;
+  background: #edf0f4;
+  font-size: 8px;
+}
+.course-flags span.failed { color: #a43f3b; background: #faeae8; }
+.pool-list article > p { margin: 8px 0; color: var(--muted); font-size: 9px; line-height: 1.5; }
+.pool-list article > p b { color: #a4423b; font-weight: 600; }
+.pool-list article > p b.ready { color: #0b796f; }
+.pool-list .el-select { width: 100%; margin-top: 9px; }
+.semester-runway > header p { margin: 5px 0 0; color: var(--muted); font-size: 9px; }
+.runway-line {
+  position: relative;
+  padding: 18px 18px 22px 82px;
+}
+.runway-line::before {
+  position: absolute;
+  top: 31px;
+  bottom: 64px;
+  left: 43px;
+  width: 2px;
+  content: "";
+  background: linear-gradient(#233b77, #0d8275 76%, #d0d6df);
+}
+.semester-stop {
+  position: relative;
+  min-height: 116px;
+  margin-bottom: 13px;
+}
+.semester-marker {
+  position: absolute;
+  top: 15px;
+  left: -67px;
+  width: 52px;
+  display: grid;
+  justify-items: center;
+  gap: 5px;
+}
+.semester-marker i {
+  width: 31px;
+  height: 31px;
+  display: grid;
+  place-items: center;
+  color: white;
+  border: 4px solid white;
+  outline: 1px solid #263c78;
+  background: #263c78;
+  font: 700 11px/1 Consolas, monospace;
+  font-style: normal;
+}
+.semester-marker span { color: var(--muted); font-size: 8px; text-align: center; }
+.semester-stop.beyond .semester-marker i { outline-color: #a7752a; background: #a7752a; }
+.semester-sheet { border: 1px solid #dce1e9; }
+.semester-sheet > header {
+  min-height: 61px;
+  padding: 10px 14px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  background: #f8f9fb;
+  border-bottom: 1px solid #e1e5eb;
+}
+.semester-sheet header span { color: var(--teal); font-size: 9px; }
+.semester-sheet header h4 { margin: 4px 0 0; font-size: 13px; }
+.semester-sheet header > b { color: var(--indigo); font: 700 18px/1 Consolas, monospace; }
+.semester-sheet header > b small { color: var(--muted); font-size: 8px; }
+.scheduled-courses {
+  padding: 9px;
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 7px;
+}
+.scheduled-courses article {
+  min-height: 58px;
+  padding: 9px 8px 9px 11px;
+  display: grid;
+  grid-template-columns: 1fr auto 25px;
+  gap: 8px;
+  align-items: center;
+  border-left: 3px solid #0c8275;
+  background: #f1f8f7;
+}
+.scheduled-courses article.conflicted { border-color: #b64b43; background: #fff1ef; }
+.scheduled-courses span { color: var(--muted); font-size: 8px; }
+.scheduled-courses b { display: block; margin-top: 4px; font-size: 10px; }
+.scheduled-courses small { color: var(--muted); font-size: 8px; }
+.empty-semester { margin: 0; padding: 18px 14px; color: #9199a8; font-size: 9px; }
+.graduation-gate {
+  min-height: 76px;
+  padding: 14px 18px;
+  display: grid;
+  grid-template-columns: 145px 1fr auto;
+  gap: 16px;
+  align-items: center;
+  color: #5d6676;
+  border: 1px dashed #aeb6c3;
+  background: #f7f8fa;
+}
+.graduation-gate.ready {
+  color: #075f59;
+  border-color: #2b9187;
+  background: #edf8f6;
+}
+.graduation-gate span { font: 700 9px/1.2 Consolas, monospace; letter-spacing: .1em; }
+.graduation-gate b { font-size: 13px; }
+.graduation-gate p { margin: 0; font-size: 9px; }
+.planning-closeout {
+  padding: 19px;
+  display: grid;
+  grid-template-columns: 190px 1fr minmax(260px, .7fr);
+  gap: 20px;
+  align-items: start;
+  border: 1px solid var(--line);
+  background: white;
+}
+.planning-closeout > div:first-child span { color: var(--teal); font-size: 9px; font-weight: 700; }
+.planning-closeout h3 { margin: 7px 0 0; font-size: 15px; }
+.missing-requirements { display: flex; flex-wrap: wrap; gap: 6px; }
+.missing-requirements span {
+  padding: 5px 7px;
+  color: #705829;
+  border: 1px solid #ead6aa;
+  background: #fff9ed;
+  font-size: 9px;
+}
+.missing-requirements em { color: #0d766d; font-size: 10px; font-style: normal; }
+.planning-closeout ul { margin: 0; padding-left: 16px; color: var(--muted); font-size: 9px; line-height: 1.7; }
+
+@media (max-width: 1050px) {
+  .planning-cockpit { grid-template-columns: 1.2fr .8fr; }
+  .arrival-board { grid-column: 1 / -1; border-top: 1px solid rgba(255,255,255,.16); border-left: 0; }
+  .planner-workspace { grid-template-columns: 300px minmax(0, 1fr); }
+  .scheduled-courses { grid-template-columns: 1fr; }
+  .planning-closeout { grid-template-columns: 170px 1fr; }
+  .planning-closeout ul { grid-column: 1 / -1; }
+}
+
+@media (max-width: 760px) {
+  .planning-cockpit { grid-template-columns: 1fr; }
+  .completion-dial,
+  .arrival-board { border-top: 1px solid rgba(255,255,255,.16); border-left: 0; }
+  .planning-metrics { grid-template-columns: 1fr 1fr; }
+  .planning-metrics > div:nth-child(2) { border-right: 0; }
+  .planning-metrics > div:nth-child(-n + 2) { border-bottom: 1px solid var(--line); }
+  .official-audit-strip { grid-template-columns: 1fr; gap: 7px; }
+  .official-audit-strip em { width: max-content; }
+  .planning-alerts { grid-template-columns: 1fr; }
+  .next-term-brief { grid-template-columns: 1fr; gap: 8px; }
+  .planner-workspace { grid-template-columns: 1fr; }
+  .course-pool { position: static; }
+  .pool-list { max-height: 460px; }
+  .runway-line { padding-left: 64px; }
+  .runway-line::before { left: 31px; }
+  .semester-marker { left: -55px; }
+  .graduation-gate { grid-template-columns: 1fr; gap: 6px; }
+  .planning-closeout { grid-template-columns: 1fr; }
+  .planning-closeout ul { grid-column: auto; }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .completion-dial em,
+  .pool-list > article { transition: none; }
+}
+</style>

web/src/views/CoursesView.vue

@@ -11,6 +11,7 @@ const rows = ref<any[]>([])
 const total = ref(0)
 const colleges = ref<any[]>([])
 const categories = ref<any[]>([])
+const courseOptions = ref<any[]>([])
 const dialogVisible = ref(false)
 const editingId = ref('')
 const importing = ref(false)
@@ -61,6 +62,9 @@ const maintenanceScope = computed(() =>
     ? `${formColleges.value[0]?.name ?? '所属学院'} · 专业课与实践课`
     : '全校课程 · 全性质',
 )
+const prerequisiteOptions = computed(() =>
+  courseOptions.value.filter((item) => item.id !== editingId.value),
+)
 
 function canManageRow(row: any) {
   return row.canManage === true
@@ -81,6 +85,7 @@ function resetForm(row?: any) {
     nature: isCollegeAdmin.value ? 'MajorRequired' : 'GeneralRequired',
     assessmentMethod: 'Examination',
     description: '',
+    prerequisiteCourseIds: [],
     isEnabled: true,
     sortOrder: 0,
   }, row ?? {})
@@ -168,6 +173,7 @@ async function handleImport(event: Event) {
     )
     query.page = 1
     await load()
+    courseOptions.value = (await http.get('/courses/options')).data
   } catch (error) {
     ElMessage.error(apiErrorMessage(error))
   } finally {
@@ -203,6 +209,7 @@ async function save() {
     ElMessage.success(editingId.value ? '课程已更新' : '课程已加入课程库')
     dialogVisible.value = false
     await load()
+    courseOptions.value = (await http.get('/courses/options')).data
   } catch (error) {
     ElMessage.error(apiErrorMessage(error))
   }
@@ -224,12 +231,14 @@ async function remove(row: any) {
 }
 
 onMounted(async () => {
-  const [collegeRes, categoryRes] = await Promise.all([
+  const [collegeRes, categoryRes, courseRes] = await Promise.all([
     http.get('/base-data/colleges'),
     http.get('/base-data/course-categories'),
+    http.get('/courses/options'),
   ])
   colleges.value = collegeRes.data
   categories.value = categoryRes.data
+  courseOptions.value = courseRes.data
   await load()
 })
 </script>
@@ -331,6 +340,14 @@ onMounted(async () => {
         <el-table-column label="考核" width="80">
           <template #default="{ row }">{{ assessmentLabels[row.assessmentMethod] }}</template>
         </el-table-column>
+        <el-table-column label="先修课程" min-width="180">
+          <template #default="{ row }">
+            <span v-if="row.prerequisites?.length" class="prerequisite-list">
+              {{ row.prerequisites.map((item: any) => item.code).join('、') }}
+            </span>
+            <span v-else>—</span>
+          </template>
+        </el-table-column>
         <el-table-column label="状态" width="85">
           <template #default="{ row }">
             <span class="table-status" :class="{ off: !row.isEnabled }">{{ row.isEnabled ? '启用' : '停用' }}</span>
@@ -407,6 +424,24 @@ onMounted(async () => {
           <el-form-item label="讲授学时"><el-input-number v-model="form.lectureHours" :min="0" /></el-form-item>
           <el-form-item label="实践学时"><el-input-number v-model="form.practiceHours" :min="0" /></el-form-item>
         </div>
+        <el-form-item label="先修课程">
+          <el-select
+            v-model="form.prerequisiteCourseIds"
+            multiple
+            filterable
+            collapse-tags
+            collapse-tags-tooltip
+            placeholder="选择修读本课程前必须通过的课程"
+          >
+            <el-option
+              v-for="item in prerequisiteOptions"
+              :key="item.id"
+              :label="`${item.code} · ${item.name}`"
+              :value="item.id"
+            />
+          </el-select>
+          <span class="field-hint">学生规划时会检查这些课程是否已经通过，或安排在更早的模拟学期。</span>
+        </el-form-item>
         <el-form-item label="课程简介"><el-input v-model="form.description" type="textarea" :rows="3" /></el-form-item>
         <div class="form-grid compact">
           <el-form-item label="排序"><el-input-number v-model="form.sortOrder" :min="0" /></el-form-item>

web/src/views/StudentCurriculumView.vue

@@ -88,7 +88,10 @@ onMounted(load)
         <h2>我的培养方案</h2>
         <p>按培养方案核对已完成、在读、重修与尚未通过的课程。</p>
       </div>
+      <div class="page-actions">
+        <el-button @click="$router.push('/academic-planning')">学业规划与毕业模拟</el-button>
         <el-button :icon="Refresh" @click="load">刷新进度</el-button>
+      </div>
     </section>
 
     <section v-if="student" class="student-plan-head">