feat(assignments): add PDF submission export for teachers

package.json

@@ -14,6 +14,7 @@
     "@aws-sdk/client-s3": "^3.922.0",
     "@clerk/nextjs": "^6.34.1",
     "@prisma/client": "^5.22.0",
+    "jszip": "^3.10.1",
     "next": "^15.4.2",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",

src/app/api/assignments/[assignmentId]/submissions/export-pdf/route.ts

@@ -0,0 +1,102 @@
+import { auth } from "@clerk/nextjs/server";
+import JSZip from "jszip";
+import { NextResponse } from "next/server";
+import { prisma } from "@/lib/prisma";
+import { getNumericParam } from "@/lib/route-params";
+import { loadSubmissionBuffer } from "@/lib/assignment-evaluation";
+
+type AssignmentRouteParams = { assignmentId: string | string[] | undefined };
+
+const sanitizeFilenameSegment = (value: string, fallback: string) => {
+  const cleaned = value
+    .replace(/[\\/:*?"<>|]+/g, "_")
+    .replace(/\s+/g, " ")
+    .trim()
+    .replace(/^\.+/, "")
+    .replace(/\.+$/, "");
+  return cleaned || fallback;
+};
+
+export async function GET(
+  _request: Request,
+  { params }: { params: Promise<AssignmentRouteParams> },
+) {
+  const resolvedParams = await params;
+  const assignmentId = getNumericParam(resolvedParams.assignmentId);
+  if (Number.isNaN(assignmentId)) {
+    return NextResponse.json({ error: "作业不存在" }, { status: 400 });
+  }
+
+  const { userId } = await auth();
+  if (!userId) {
+    return NextResponse.json({ error: "未授权" }, { status: 401 });
+  }
+
+  const assignment = await prisma.assignment.findFirst({
+    where: { id: assignmentId, teacherId: userId },
+    select: { id: true, title: true },
+  });
+
+  if (!assignment) {
+    return NextResponse.json({ error: "未找到作业" }, { status: 404 });
+  }
+
+  const submissions = await prisma.submission.findMany({
+    where: { assignmentId },
+    orderBy: { submittedAt: "asc" },
+    select: {
+      id: true,
+      studentId: true,
+      studentName: true,
+      fileKey: true,
+      fileUrl: true,
+    },
+  });
+
+  if (submissions.length === 0) {
+    return NextResponse.json({ error: "暂无提交可导出" }, { status: 404 });
+  }
+
+  const assignmentTitle = sanitizeFilenameSegment(
+    assignment.title ?? `assignment-${assignmentId}`,
+    `assignment-${assignmentId}`,
+  );
+
+  try {
+    const zip = new JSZip();
+    for (const submission of submissions) {
+      const buffer = await loadSubmissionBuffer(submission.fileKey, submission.fileUrl);
+      const studentId = sanitizeFilenameSegment(
+        submission.studentId || `student-${submission.id}`,
+        `student-${submission.id}`,
+      );
+      const studentName = sanitizeFilenameSegment(
+        submission.studentName || "unknown",
+        "unknown",
+      );
+      const filename = `${studentId}-${studentName}-${assignmentTitle}.pdf`;
+      zip.file(filename, buffer);
+    }
+
+    const zipBuffer = await zip.generateAsync({
+      type: "nodebuffer",
+      compression: "DEFLATE",
+      compressionOptions: { level: 6 },
+    });
+
+    const zipFilename = `${assignmentTitle}_submissions_pdf.zip`;
+    const encodedFilename = encodeURIComponent(zipFilename);
+
+    return new NextResponse(zipBuffer, {
+      headers: {
+        "Content-Type": "application/zip",
+        "Content-Length": zipBuffer.length.toString(),
+        "Content-Disposition": `attachment; filename="${encodedFilename}"; filename*=UTF-8''${encodedFilename}`,
+        "Cache-Control": "no-store",
+      },
+    });
+  } catch (error) {
+    console.error(`Failed to export submissions for assignment ${assignmentId}`, error);
+    return NextResponse.json({ error: "导出压缩包失败" }, { status: 500 });
+  }
+}

src/app/teacher/page.tsx

@@ -159,6 +159,7 @@ export default function TeacherPage() {
   const [gradingCriteriaDraft, setGradingCriteriaDraft] = useState("");
   const [autoEvaluateDraft, setAutoEvaluateDraft] = useState(false);
   const [isExporting, setIsExporting] = useState(false);
+  const [isExportingPdf, setIsExportingPdf] = useState(false);
   const [isCustomExportModalVisible, setIsCustomExportModalVisible] = useState(false);
   const [selectedExportColumns, setSelectedExportColumns] = useState<
     Array<(typeof EXPORTABLE_COLUMNS)[number]["key"]>
@@ -341,6 +342,51 @@ export default function TeacherPage() {
     setIsCustomExportModalVisible(false);
   };
 
+  const handleExportAllSubmissionsPdf = useCallback(async () => {
+    if (!selectedAssignment) {
+      setError("请选择作业");
+      return;
+    }
+    if (submissions.length === 0) {
+      setError("暂无提交可导出");
+      return;
+    }
+
+    setIsExportingPdf(true);
+    setError("");
+    setInfo("");
+    try {
+      const response = await fetch(
+        `/api/assignments/${selectedAssignment}/submissions/export-pdf`,
+      );
+      if (!response.ok) {
+        const data = await response.json().catch(() => ({}));
+        throw new Error(data?.error ?? "导出失败");
+      }
+      const blob = await response.blob();
+      const downloadUrl = window.URL.createObjectURL(blob);
+      const link = document.createElement("a");
+      const disposition = response.headers.get("Content-Disposition") ?? "";
+      const utf8Match = disposition.match(/filename\*=UTF-8''([^;]+)/i);
+      const asciiMatch = disposition.match(/filename=\"?([^\";]+)\"?/i);
+      const headerFilename = utf8Match?.[1] ?? asciiMatch?.[1];
+      const filename =
+        (headerFilename ? decodeURIComponent(headerFilename) : null) ??
+        `assignment-${selectedAssignment}-submissions.zip`;
+      link.href = downloadUrl;
+      link.download = filename;
+      document.body.appendChild(link);
+      link.click();
+      document.body.removeChild(link);
+      window.URL.revokeObjectURL(downloadUrl);
+      setInfo("导出成功");
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "导出失败");
+    } finally {
+      setIsExportingPdf(false);
+    }
+  }, [selectedAssignment, submissions.length]);
+
   const handleDownloadSubmission = useCallback(
     async (submission: Submission) => {
       setError("");
@@ -861,6 +907,17 @@ export default function TeacherPage() {
                 >
                   导出学号和分数
                 </button>
+                <button
+                  type="button"
+                  style={{
+                    ...secondaryButtonStyle,
+                    opacity: isExportingPdf || submissions.length === 0 ? 0.7 : 1,
+                  }}
+                  disabled={isExportingPdf || submissions.length === 0}
+                  onClick={handleExportAllSubmissionsPdf}
+                >
+                  导出所有提交 PDF
+                </button>
                 <button
                   type="button"
                   style={{