Fix security, transaction, and badge issues from final review

- Validate file URLs against S3 prefix in messages route (Fix 1)
- Guard attachment hrefs with https:// check in QuestionThread and QuestionSplitView (Fix 2)
- Wrap message create + updatedAt bump in prisma.$transaction (Fix 3)
- Add questionsBadge count query to curator layout for admin branch (Fix 4)
- Fire-and-forget email sends with void Promise.all (Fix 5)
- Wrap req.json() calls in try/catch returning 400 on parse failure (Fix 6)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/specs/20260519-student-questions-design.md

@@ -0,0 +1,159 @@
+# Student Questions — Design Spec
+_Created: 20260519_
+
+## Overview
+
+A support-chat feature inside the LMS. Students ask questions, school staff (admin/curator) answers. Each question is a threaded conversation with open/closed status. Includes file attachments and email notifications for all parties.
+
+Also in scope: email notifications for homework submissions (new + student updates).
+
+---
+
+## Data Model
+
+### StudentQuestion
+```
+id            String   @id @default(cuid())
+userId        String                          -- student who created it
+courseId      String?                         -- optional course context
+title         String
+status        QuestionStatus @default(OPEN)   -- OPEN | CLOSED
+closedAt      DateTime?
+closedById    String?                         -- admin/curator who closed
+createdAt     DateTime @default(now())
+updatedAt     DateTime @updatedAt
+
+user          User
+course        Course?
+messages      StudentQuestionMessage[]
+```
+
+### StudentQuestionMessage
+```
+id            String   @id @default(cuid())
+questionId    String
+authorId      String
+text          String
+files         String[] -- S3 paths: questions/{questionId}/{messageId}/{filename}
+isRead        Boolean  @default(false)
+createdAt     DateTime @default(now())
+
+question      StudentQuestion
+author        User
+```
+
+### QuestionStatus (enum)
+```
+OPEN
+CLOSED
+```
+
+---
+
+## Routes
+
+### Student
+| Route | Description |
+|---|---|
+| `(student)/questions` | List of own questions with unread indicators |
+| `(student)/questions/new` | Form to create a new question |
+| `(student)/questions/[id]` | Thread view — read messages + reply |
+
+### Admin / Curator
+| Route | Description |
+|---|---|
+| `admin/questions` | Split-view: question list left, thread right |
+| `curator/questions` | Same split-view (curators have same access as admins here) |
+
+---
+
+## UI Behaviour
+
+### Student — Questions List (`/questions`)
+- Header: "Мои вопросы" + "+ Задать вопрос" button (→ `/questions/new`)
+- Each row: title, message count, last activity, status badge (ОТКРЫТ / ЗАКРЫТ)
+- Unread indicator: black dot + "Новый ответ от школы" when school replied since last student visit
+- Closed questions: dimmed (opacity 0.7), grey badge
+- Active (unread) questions: bold border, bold title
+
+### Student — Thread (`/questions/[id]`)
+- Header: question title, created date, status, "← Все вопросы" link
+- Message bubbles: student messages left (#E8E8E0), school messages right (#F5F5F0 + green border #E8F0D8)
+- New school message: bold label "🔵 новое" in timestamp
+- File attachments shown inline under message text (📎 filename · size)
+- Reply form at bottom: textarea + attach button + send button
+- Attachment types: jpg, png, pdf, md · max 10 MB
+- Student CAN reply to closed questions (creates new message, does NOT reopen question)
+
+### Admin/Curator — Split View (`/admin/questions`, `/curator/questions`)
+- Left panel (45%): tab filter "Открытые / Закрытые", question list sorted by last activity
+- Unread: red dot, green-tinted background, bold student name
+- Right panel (55%): selected thread with full message history + reply form + "✓ Закрыть вопрос" button
+- Only admin/curator can close a question
+- Closing a question does NOT prevent further messages
+
+---
+
+## Notifications
+
+### → School (admin + all curators)
+| Trigger | Channel |
+|---|---|
+| New question created | Email + admin sidebar badge (count of unread questions) |
+| Student adds message to existing question | Email |
+
+### → Student
+| Trigger | Channel |
+|---|---|
+| Admin/curator replies to question | Email |
+
+### Admin Badge
+- Sidebar badge shows count of questions with unread messages (school hasn't seen yet)
+- Separate from homework badge
+
+### Email for Homework (added to scope)
+| Trigger | Recipient |
+|---|---|
+| New HomeworkSubmission created | Admin + all curators |
+| Student updates existing submission (adds text/file) | Admin + all curators |
+
+---
+
+## File Storage
+
+- Path pattern: `questions/{questionId}/{messageId}/{filename}`
+- Reuse existing S3 upload infrastructure (`src/lib/s3.ts`)
+- Allowed: jpg, png, pdf, md
+- Max size: 10 MB per file
+- No limit on number of files per message (reasonable: 5)
+
+---
+
+## Read Tracking
+
+- `isRead` flag per message, set to `true` when the OTHER party opens the thread
+- Student opens `/questions/[id]` → all school messages in that thread marked `isRead = true`
+- Admin/curator opens a question in split-view → all student messages marked `isRead = true`
+- Admin badge recalculates on each page load (count questions where latest student message is unread)
+
+---
+
+## API Routes
+
+```
+POST   /api/questions                    -- create question
+GET    /api/questions                    -- list own questions (student) or all (admin/curator)
+GET    /api/questions/[id]               -- get question + messages
+POST   /api/questions/[id]/messages      -- add message + files
+PATCH  /api/questions/[id]/close         -- close question (admin/curator only)
+POST   /api/upload/question-file         -- upload attachment, returns S3 path
+```
+
+---
+
+## Out of Scope (this iteration)
+- Question categories / tags
+- Assigning question to a specific curator
+- Email threading (reply-to email to answer)
+- Push/browser notifications
+- Question templates

prisma/migrations/20260519100000_add_student_questions/migration.sql

@@ -0,0 +1,45 @@
+-- CreateEnum
+CREATE TYPE "QuestionStatus" AS ENUM ('OPEN', 'CLOSED');
+
+-- CreateTable
+CREATE TABLE "StudentQuestion" (
+    "id" TEXT NOT NULL,
+    "userId" TEXT NOT NULL,
+    "courseId" TEXT,
+    "title" TEXT NOT NULL,
+    "status" "QuestionStatus" NOT NULL DEFAULT 'OPEN',
+    "closedAt" TIMESTAMP(3),
+    "closedById" TEXT,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "StudentQuestion_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "StudentQuestionMessage" (
+    "id" TEXT NOT NULL,
+    "questionId" TEXT NOT NULL,
+    "authorId" TEXT NOT NULL,
+    "text" TEXT NOT NULL,
+    "files" JSONB,
+    "isRead" BOOLEAN NOT NULL DEFAULT false,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "StudentQuestionMessage_pkey" PRIMARY KEY ("id")
+);
+
+-- AddForeignKey
+ALTER TABLE "StudentQuestion" ADD CONSTRAINT "StudentQuestion_userId_fkey" FOREIGN KEY ("userId") REFERENCES "User"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "StudentQuestion" ADD CONSTRAINT "StudentQuestion_courseId_fkey" FOREIGN KEY ("courseId") REFERENCES "Course"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "StudentQuestion" ADD CONSTRAINT "StudentQuestion_closedById_fkey" FOREIGN KEY ("closedById") REFERENCES "User"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "StudentQuestionMessage" ADD CONSTRAINT "StudentQuestionMessage_questionId_fkey" FOREIGN KEY ("questionId") REFERENCES "StudentQuestion"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "StudentQuestionMessage" ADD CONSTRAINT "StudentQuestionMessage_authorId_fkey" FOREIGN KEY ("authorId") REFERENCES "User"("id") ON DELETE CASCADE ON UPDATE CASCADE;

prisma/migrations/20260519110000_add_student_questions_indexes/migration.sql

@@ -0,0 +1,8 @@
+-- CreateIndex
+CREATE INDEX "StudentQuestion_userId_idx" ON "StudentQuestion"("userId");
+
+-- CreateIndex
+CREATE INDEX "StudentQuestion_status_idx" ON "StudentQuestion"("status");
+
+-- CreateIndex
+CREATE INDEX "StudentQuestionMessage_questionId_idx" ON "StudentQuestionMessage"("questionId");

prisma/schema.prisma

@@ -37,6 +37,9 @@ model User {
   accessLogs           AccessLog[] @relation("AccessLogUser")
   adminAccessLogs      AccessLog[] @relation("AccessLogAdmin")
   balanceTransactions  BalanceTransaction[]
+  questions            StudentQuestion[]
+  closedQuestions      StudentQuestion[]       @relation("QuestionClosedBy")
+  questionMessages     StudentQuestionMessage[]
 }
 
 model Session {
@@ -111,6 +114,7 @@ model Course {
   modules     Module[]
   enrollments CourseEnrollment[]
   accessLogs  AccessLog[]
+  questions   StudentQuestion[]
 }
 
 model Module {
@@ -312,6 +316,50 @@ model LessonComment {
   replies LessonComment[] @relation("CommentReplies")
 }
 
+// ─────────────────────────────────────────────
+// Student Questions
+// ─────────────────────────────────────────────
+
+enum QuestionStatus {
+  OPEN
+  CLOSED
+}
+
+model StudentQuestion {
+  id         String         @id @default(cuid())
+  userId     String
+  courseId   String?
+  title      String
+  status     QuestionStatus @default(OPEN)
+  closedAt   DateTime?
+  closedById String?
+  createdAt  DateTime       @default(now())
+  updatedAt  DateTime       @updatedAt
+
+  user      User                     @relation(fields: [userId], references: [id], onDelete: Cascade)
+  course    Course?                  @relation(fields: [courseId], references: [id], onDelete: SetNull)
+  closedBy  User?                    @relation("QuestionClosedBy", fields: [closedById], references: [id], onDelete: SetNull)
+  messages  StudentQuestionMessage[]
+
+  @@index([userId])
+  @@index([status])
+}
+
+model StudentQuestionMessage {
+  id         String   @id @default(cuid())
+  questionId String
+  authorId   String
+  text       String
+  files      Json?    // [{name, url, size}]
+  isRead     Boolean  @default(false)
+  createdAt  DateTime @default(now())
+
+  question StudentQuestion @relation(fields: [questionId], references: [id], onDelete: Cascade)
+  author   User            @relation(fields: [authorId], references: [id], onDelete: Cascade)
+
+  @@index([questionId])
+}
+
 // ─────────────────────────────────────────────
 // Balance
 // ─────────────────────────────────────────────

src/app/(student)/courses/[slug]/lessons/[lessonId]/homework-actions.ts

@@ -4,7 +4,7 @@ import { prisma } from "@/lib/prisma";
 import { auth } from "@/lib/auth";
 import { headers } from "next/headers";
 import { revalidatePath } from "next/cache";
-import { sendHomeworkSubmittedEmail } from "@/lib/email";
+import { sendHomeworkSubmittedEmail, sendHomeworkUpdatedEmail } from "@/lib/email";
 
 interface HomeworkFile {
   name: string;
@@ -40,6 +40,27 @@ export async function submitHomework(
       data: { text, files: files as object[], audioUrl: audioUrl ?? null, submittedAt: new Date() },
     });
     submissionId = updated.id;
+
+    // Notify admins/curators when student edits an existing submission
+    const [lessonRecord, staff] = await Promise.all([
+      prisma.homework.findUnique({
+        where: { id: homeworkId },
+        include: { lesson: { select: { title: true } } },
+      }),
+      prisma.user.findMany({
+        where: { role: { in: ["admin", "curator"] } },
+        select: { email: true, name: true },
+      }),
+    ]);
+    if (lessonRecord) {
+      await Promise.all(
+        staff.map((s) =>
+          sendHomeworkUpdatedEmail(s.email, s.name, session.user.name, lessonRecord.lesson.title, submissionId).catch(
+            (e) => console.error("[email] homework-updated:", e)
+          )
+        )
+      );
+    }
   } else {
     const created = await prisma.homeworkSubmission.create({
       data: { homeworkId, userId: session.user.id, text, files: files as object[], audioUrl: audioUrl ?? null },

src/app/(student)/layout.tsx

@@ -44,6 +44,9 @@ export default async function StudentLayout({ children }: { children: React.Reac
           {schoolName}
         </Link>
         <div className="flex items-center gap-4">
+          <Link href="/questions" className="text-sm hover:underline" style={{ color: "var(--muted-foreground)" }}>
+            Вопросы
+          </Link>
           <Link href="/profile" className="text-sm hover:underline" style={{ color: "var(--muted-foreground)" }}>
             {session.user.name}
           </Link>

src/app/(student)/questions/[id]/page.tsx

@@ -0,0 +1,86 @@
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { redirect, notFound } from "next/navigation";
+import { prisma } from "@/lib/prisma";
+import Link from "next/link";
+import { QuestionThread } from "@/components/questions/QuestionThread";
+
+export default async function QuestionThreadPage({
+  params,
+}: {
+  params: Promise<{ id: string }>;
+}) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) redirect("/login");
+
+  const { id } = await params;
+
+  const question = await prisma.studentQuestion.findUnique({
+    where: { id },
+    include: {
+      user: { select: { id: true, name: true } },
+      messages: {
+        include: { author: { select: { id: true, name: true, role: true } } },
+        orderBy: { createdAt: "asc" },
+      },
+    },
+  });
+
+  if (!question || question.userId !== session.user.id) notFound();
+
+  // Mark staff messages as read
+  await prisma.studentQuestionMessage.updateMany({
+    where: {
+      questionId: id,
+      isRead: false,
+      NOT: { authorId: session.user.id },
+    },
+    data: { isRead: true },
+  });
+
+  return (
+    <div className="max-w-2xl mx-auto px-4 py-8">
+      <div className="flex items-start justify-between mb-6">
+        <div>
+          <h1 className="text-lg font-bold mb-1" style={{ color: "var(--foreground)" }}>
+            {question.title}
+          </h1>
+          <p className="text-xs" style={{ color: "var(--muted-foreground)" }}>
+            Создан{" "}
+            {new Date(question.createdAt).toLocaleDateString("ru", {
+              day: "numeric",
+              month: "long",
+            })}{" "}
+            ·{" "}
+            <span
+              style={{
+                color: question.status === "OPEN" ? "var(--foreground)" : "var(--muted-foreground)",
+                fontWeight: 700,
+              }}
+            >
+              {question.status === "OPEN" ? "● Открыт" : "✓ Закрыт"}
+            </span>
+          </p>
+        </div>
+        <Link
+          href="/questions"
+          className="text-xs"
+          style={{ color: "var(--muted-foreground)", textDecoration: "underline" }}
+        >
+          ← Все вопросы
+        </Link>
+      </div>
+
+      <QuestionThread
+        questionId={id}
+        questionStatus={question.status as "OPEN" | "CLOSED"}
+        currentUserId={session.user.id}
+        initialMessages={question.messages.map((m) => ({
+          ...m,
+          files: m.files as Array<{ name: string; url: string; size: number }> | null,
+          createdAt: m.createdAt.toISOString(),
+        }))}
+      />
+    </div>
+  );
+}

src/app/(student)/questions/new/page.tsx

@@ -0,0 +1,122 @@
+"use client";
+
+import { useState } from "react";
+import { useRouter } from "next/navigation";
+import Link from "next/link";
+
+export default function NewQuestionPage() {
+  const router = useRouter();
+  const [title, setTitle] = useState("");
+  const [text, setText] = useState("");
+  const [loading, setLoading] = useState(false);
+  const [error, setError] = useState("");
+
+  async function handleSubmit(e: React.FormEvent) {
+    e.preventDefault();
+    if (!title.trim() || !text.trim()) return;
+    setLoading(true);
+    setError("");
+
+    try {
+      const res = await fetch("/api/questions", {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ title, text }),
+      });
+      if (!res.ok) {
+        const data = await res.json();
+        throw new Error(data.error ?? "Ошибка при создании вопроса");
+      }
+      const q = await res.json();
+      router.push(`/questions/${q.id}`);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Ошибка");
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  return (
+    <div className="max-w-xl mx-auto px-4 py-8">
+      <div className="flex items-center gap-3 mb-6">
+        <Link
+          href="/questions"
+          className="text-sm"
+          style={{ color: "var(--muted-foreground)", textDecoration: "underline" }}
+        >
+          ← Все вопросы
+        </Link>
+      </div>
+
+      <h1 className="text-xl font-bold mb-6" style={{ color: "var(--foreground)" }}>
+        Новый вопрос
+      </h1>
+
+      <form onSubmit={handleSubmit} className="flex flex-col gap-4">
+        <div>
+          <label
+            className="block text-sm font-bold mb-1"
+            style={{ color: "var(--foreground)" }}
+          >
+            Тема вопроса
+          </label>
+          <input
+            type="text"
+            value={title}
+            onChange={(e) => setTitle(e.target.value)}
+            placeholder="Кратко опишите суть вопроса"
+            required
+            className="w-full text-sm px-3 py-2 outline-none"
+            style={{
+              border: "2px solid var(--border)",
+              background: "var(--color-surface)",
+              color: "var(--foreground)",
+            }}
+          />
+        </div>
+
+        <div>
+          <label
+            className="block text-sm font-bold mb-1"
+            style={{ color: "var(--foreground)" }}
+          >
+            Описание
+          </label>
+          <textarea
+            value={text}
+            onChange={(e) => setText(e.target.value)}
+            placeholder="Подробно опишите вопрос или проблему"
+            required
+            rows={6}
+            className="w-full text-sm px-3 py-2 outline-none resize-none"
+            style={{
+              border: "2px solid var(--border)",
+              background: "var(--color-surface)",
+              color: "var(--foreground)",
+            }}
+          />
+        </div>
+
+        {error && (
+          <p className="text-sm" style={{ color: "var(--destructive)" }}>
+            {error}
+          </p>
+        )}
+
+        <button
+          type="submit"
+          disabled={loading || !title.trim() || !text.trim()}
+          className="self-end text-sm font-bold px-6 py-2"
+          style={{
+            background: "var(--foreground)",
+            color: "var(--background)",
+            border: "none",
+            opacity: loading ? 0.6 : 1,
+          }}
+        >
+          {loading ? "Отправка..." : "Отправить →"}
+        </button>
+      </form>
+    </div>
+  );
+}

src/app/(student)/questions/page.tsx

@@ -0,0 +1,113 @@
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { redirect } from "next/navigation";
+import { prisma } from "@/lib/prisma";
+import Link from "next/link";
+
+export default async function QuestionsPage() {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) redirect("/login");
+
+  const questions = await prisma.studentQuestion.findMany({
+    where: { userId: session.user.id },
+    include: {
+      _count: {
+        select: {
+          messages: {
+            where: { isRead: false, NOT: { authorId: session.user.id } },
+          },
+        },
+      },
+      messages: {
+        orderBy: { createdAt: "desc" },
+        take: 1,
+        include: { author: { select: { name: true } } },
+      },
+    },
+    orderBy: { updatedAt: "desc" },
+  });
+
+  return (
+    <div className="max-w-2xl mx-auto px-4 py-8">
+      <div className="flex items-center justify-between mb-6">
+        <h1 className="text-xl font-bold" style={{ color: "var(--foreground)" }}>
+          Мои вопросы
+        </h1>
+        <Link
+          href="/questions/new"
+          className="text-sm font-bold px-4 py-2"
+          style={{
+            background: "var(--color-surface)",
+            border: "2px solid var(--foreground)",
+            color: "var(--foreground)",
+          }}
+        >
+          + Задать вопрос
+        </Link>
+      </div>
+
+      {questions.length === 0 && (
+        <p className="text-sm" style={{ color: "var(--muted-foreground)" }}>
+          У вас ещё нет вопросов.
+        </p>
+      )}
+
+      <div className="flex flex-col gap-2">
+        {questions.map((q) => {
+          const unread = q._count.messages > 0;
+          const lastMsg = q.messages[0];
+          return (
+            <Link
+              key={q.id}
+              href={`/questions/${q.id}`}
+              className="block p-3 rounded-sm transition-colors"
+              style={{
+                border: unread ? "2px solid var(--foreground)" : "1px solid var(--border)",
+                background: q.status === "CLOSED" ? "var(--background)" : "var(--color-surface)",
+                opacity: q.status === "CLOSED" ? 0.7 : 1,
+              }}
+            >
+              <div className="flex items-start justify-between gap-2 mb-1">
+                <span
+                  className="text-sm"
+                  style={{
+                    fontWeight: unread ? 700 : 400,
+                    color: q.status === "CLOSED" ? "var(--muted-foreground)" : "var(--foreground)",
+                  }}
+                >
+                  {q.title}
+                </span>
+                <span
+                  className="text-xs shrink-0 px-1.5 py-0.5 rounded-sm"
+                  style={
+                    q.status === "OPEN"
+                      ? { background: "#E8F0D8", border: "1px solid var(--border)", color: "var(--foreground)" }
+                      : { background: "var(--background)", color: "var(--muted-foreground)" }
+                  }
+                >
+                  {q.status === "OPEN" ? "● ОТКРЫТ" : "✓ ЗАКРЫТ"}
+                </span>
+              </div>
+              {unread && (
+                <div className="flex items-center gap-1.5 mb-1">
+                  <span
+                    className="inline-block w-2 h-2 rounded-full"
+                    style={{ background: "var(--foreground)" }}
+                  />
+                  <span className="text-xs font-bold" style={{ color: "var(--foreground)" }}>
+                    Новый ответ от школы
+                  </span>
+                </div>
+              )}
+              {lastMsg && !unread && (
+                <p className="text-xs" style={{ color: "var(--muted-foreground)" }}>
+                  последнее от {lastMsg.author.name}
+                </p>
+              )}
+            </Link>
+          );
+        })}
+      </div>
+    </div>
+  );
+}

src/app/admin/layout.tsx

@@ -2,11 +2,23 @@ import { headers } from "next/headers";
 import { auth } from "@/lib/auth";
 import { redirect } from "next/navigation";
 import { AdminShell } from "@/components/admin/admin-shell";
+import { prisma } from "@/lib/prisma";
 
 export default async function AdminLayout({ children }: { children: React.ReactNode }) {
   const session = await auth.api.getSession({ headers: await headers() });
   if (!session) redirect("/login");
   if (session.user.role !== "admin") redirect("/dashboard");
 
-  return <AdminShell userName={session.user.name}>{children}</AdminShell>;
+  const questionsBadge = await prisma.studentQuestion.count({
+    where: {
+      messages: {
+        some: {
+          isRead: false,
+          author: { role: "student" },
+        },
+      },
+    },
+  });
+
+  return <AdminShell userName={session.user.name} questionsBadge={questionsBadge}>{children}</AdminShell>;
 }

src/app/admin/questions/page.tsx

@@ -0,0 +1,11 @@
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { redirect } from "next/navigation";
+import { QuestionSplitView } from "@/components/questions/QuestionSplitView";
+
+export default async function AdminQuestionsPage() {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session || session.user.role !== "admin") redirect("/login");
+
+  return <QuestionSplitView currentUserId={session.user.id} />;
+}

src/app/api/questions/[id]/close/route.ts

@@ -0,0 +1,31 @@
+import { NextRequest, NextResponse } from "next/server";
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+
+export async function PATCH(
+  _req: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+
+  if (session.user.role !== "admin" && session.user.role !== "curator") {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+
+  const { id } = await params;
+
+  const question = await prisma.studentQuestion.findUnique({ where: { id } });
+  if (!question) return NextResponse.json({ error: "Not found" }, { status: 404 });
+  if (question.status === "CLOSED") {
+    return NextResponse.json({ error: "Already closed" }, { status: 400 });
+  }
+
+  const updated = await prisma.studentQuestion.update({
+    where: { id },
+    data: { status: "CLOSED", closedAt: new Date(), closedById: session.user.id },
+  });
+
+  return NextResponse.json(updated);
+}

src/app/api/questions/[id]/messages/route.ts

@@ -0,0 +1,104 @@
+import { NextRequest, NextResponse } from "next/server";
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+import { sendQuestionFollowUpEmail, sendQuestionReplyEmail } from "@/lib/email";
+
+interface FileAttachment {
+  name: string;
+  url: string;
+  size: number;
+}
+
+function buildS3Prefix(): string {
+  const endpoint = process.env.S3_ENDPOINT ?? "";
+  const bucket = process.env.S3_BUCKET ?? "";
+  // e.g. https://fsn1.your-objectstorage.com/lms-uploads/
+  return `${endpoint}/${bucket}/`;
+}
+
+export async function POST(
+  req: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+
+  const { id } = await params;
+  const isStaff = session.user.role === "admin" || session.user.role === "curator";
+
+  const question = await prisma.studentQuestion.findUnique({
+    where: { id },
+    include: { user: { select: { id: true, name: true, email: true } } },
+  });
+
+  if (!question) return NextResponse.json({ error: "Not found" }, { status: 404 });
+  if (!isStaff && question.userId !== session.user.id) {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+  if (question.status === "CLOSED") {
+    return NextResponse.json({ error: "Question is closed" }, { status: 409 });
+  }
+
+  let body: unknown;
+  try {
+    body = await req.json();
+  } catch {
+    return NextResponse.json({ error: "Invalid JSON" }, { status: 400 });
+  }
+  const { text, files } = body as { text: string; files?: FileAttachment[] };
+
+  if (!text?.trim()) {
+    return NextResponse.json({ error: "text is required" }, { status: 400 });
+  }
+
+  const s3Prefix = buildS3Prefix();
+  const safeFiles = files
+    ?.filter(
+      (f) =>
+        typeof f.name === "string" &&
+        typeof f.url === "string" &&
+        f.url.startsWith("https://") &&
+        f.url.startsWith(s3Prefix) &&
+        typeof f.size === "number"
+    )
+    .map((f) => ({ name: f.name.slice(0, 255), url: f.url, size: Math.max(0, f.size) }));
+
+  const [msg] = await prisma.$transaction([
+    prisma.studentQuestionMessage.create({
+      data: {
+        questionId: id,
+        authorId: session.user.id,
+        text: text.trim(),
+        files: safeFiles?.length ? (safeFiles as object[]) : undefined,
+      },
+      include: { author: { select: { id: true, name: true, role: true } } },
+    }),
+    prisma.studentQuestion.update({
+      where: { id },
+      data: { updatedAt: new Date() },
+    }),
+  ]);
+
+  // Send notifications (fire-and-forget, outside transaction)
+  if (isStaff) {
+    void sendQuestionReplyEmail(
+      question.user.email,
+      question.user.name,
+      question.title,
+      id,
+    );
+  } else {
+    const staff = await prisma.user.findMany({
+      where: { role: { in: ["admin", "curator"] } },
+      select: { email: true, name: true },
+    });
+    void Promise.all(
+      staff.map((s) =>
+        sendQuestionFollowUpEmail(s.email, s.name, session.user.name, question.title)
+      )
+    );
+  }
+
+  return NextResponse.json(msg, { status: 201 });
+}

src/app/api/questions/[id]/route.ts

@@ -0,0 +1,44 @@
+import { NextRequest, NextResponse } from "next/server";
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+
+export async function GET(
+  _req: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+
+  const { id } = await params;
+  const isStaff = session.user.role === "admin" || session.user.role === "curator";
+
+  const question = await prisma.studentQuestion.findUnique({
+    where: { id },
+    include: {
+      user: { select: { id: true, name: true } },
+      course: { select: { id: true, title: true } },
+      messages: {
+        include: { author: { select: { id: true, name: true, role: true } } },
+        orderBy: { createdAt: "asc" },
+      },
+    },
+  });
+
+  if (!question) return NextResponse.json({ error: "Not found" }, { status: 404 });
+  if (!isStaff && question.userId !== session.user.id) {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+
+  // Mark unread messages as read
+  const unreadWhere = isStaff
+    ? { questionId: id, isRead: false, author: { role: "student" } }
+    : { questionId: id, isRead: false, NOT: { authorId: session.user.id } };
+
+  await prisma.studentQuestionMessage.updateMany({
+    where: unreadWhere,
+    data: { isRead: true },
+  });
+
+  return NextResponse.json(question);
+}

src/app/api/questions/route.ts

@@ -0,0 +1,97 @@
+import { NextRequest, NextResponse } from "next/server";
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { prisma } from "@/lib/prisma";
+import { sendQuestionCreatedEmail } from "@/lib/email";
+
+export async function GET() {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+
+  const isStaff = session.user.role === "admin" || session.user.role === "curator";
+
+  const userSelect = isStaff
+    ? { id: true as const, name: true as const, email: true as const }
+    : { id: true as const, name: true as const };
+
+  const questions = await prisma.studentQuestion.findMany({
+    where: isStaff ? undefined : { userId: session.user.id },
+    include: {
+      user: { select: userSelect },
+      course: { select: { id: true, title: true } },
+      _count: {
+        select: {
+          messages: {
+            where: isStaff
+              ? { isRead: false, author: { role: "student" } }
+              : { isRead: false, NOT: { authorId: session.user.id } },
+          },
+        },
+      },
+    },
+    orderBy: { updatedAt: "desc" },
+  });
+
+  return NextResponse.json(
+    questions.map((q) => ({
+      id: q.id,
+      title: q.title,
+      status: q.status,
+      createdAt: q.createdAt,
+      updatedAt: q.updatedAt,
+      user: q.user,
+      course: q.course,
+      unreadCount: q._count.messages,
+    }))
+  );
+}
+
+export async function POST(req: NextRequest) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  if (session.user.role !== "student") {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+
+  let body: unknown;
+  try {
+    body = await req.json();
+  } catch {
+    return NextResponse.json({ error: "Invalid JSON" }, { status: 400 });
+  }
+  const { title, text, courseId } = body as {
+    title: string;
+    text: string;
+    courseId?: string;
+  };
+
+  if (!title?.trim() || !text?.trim()) {
+    return NextResponse.json({ error: "title and text are required" }, { status: 400 });
+  }
+
+  const question = await prisma.studentQuestion.create({
+    data: {
+      userId: session.user.id,
+      courseId: courseId ?? null,
+      title: title.trim(),
+      messages: {
+        create: {
+          authorId: session.user.id,
+          text: text.trim(),
+        },
+      },
+    },
+  });
+
+  const staff = await prisma.user.findMany({
+    where: { role: { in: ["admin", "curator"] } },
+    select: { email: true, name: true },
+  });
+  void Promise.all(
+    staff.map((s) =>
+      sendQuestionCreatedEmail(s.email, s.name, session.user.name, title.trim())
+    )
+  );
+
+  return NextResponse.json(question, { status: 201 });
+}

src/app/api/student/question-upload/route.ts

@@ -0,0 +1,43 @@
+import { NextRequest, NextResponse } from "next/server";
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { uploadFile } from "@/lib/s3";
+import { randomUUID } from "crypto";
+
+const ALLOWED_TYPES = new Set([
+  "image/jpeg", "image/png", "image/gif", "image/webp",
+  "application/pdf", "text/markdown", "text/x-markdown", "text/plain",
+]);
+const MAX_BYTES = 10 * 1024 * 1024; // 10 MB
+
+export async function POST(req: NextRequest) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+
+  const form = await req.formData();
+  const file = form.get("file") as File | null;
+  if (!file) return NextResponse.json({ error: "Missing file" }, { status: 400 });
+
+  if (file.size > MAX_BYTES) {
+    return NextResponse.json({ error: "Файл слишком большой (макс. 10 МБ)" }, { status: 413 });
+  }
+
+  if (!ALLOWED_TYPES.has(file.type)) {
+    return NextResponse.json(
+      { error: "Разрешены только jpg, png, pdf, md" },
+      { status: 415 }
+    );
+  }
+
+  const ext = file.name.split(".").pop()?.toLowerCase() ?? "bin";
+  const ALLOWED_EXTS = new Set(["jpg", "jpeg", "png", "gif", "webp", "pdf", "md", "txt"]);
+  if (!ALLOWED_EXTS.has(ext)) {
+    return NextResponse.json({ error: "Недопустимое расширение файла" }, { status: 415 });
+  }
+
+  const key = `questions/${session.user.id}/${randomUUID()}.${ext}`;
+  const buffer = Buffer.from(await file.arrayBuffer());
+  const url = await uploadFile(key, buffer, file.type);
+
+  return NextResponse.json({ name: file.name, url, size: file.size });
+}

src/app/curator/layout.tsx

@@ -5,6 +5,7 @@ import Link from "next/link";
 import { LogoutButton } from "@/components/layout/logout-button";
 import { AdminShell } from "@/components/admin/admin-shell";
 import { getSetting } from "@/lib/settings";
+import { prisma } from "@/lib/prisma";
 
 export default async function CuratorLayout({ children }: { children: React.ReactNode }) {
   const session = await auth.api.getSession({ headers: await headers() });
@@ -19,7 +20,17 @@ export default async function CuratorLayout({ children }: { children: React.Reac
 
   // Admin uses the admin shell with sidebar
   if (session.user.role === "admin") {
-    return <AdminShell userName={session.user.name}>{children}</AdminShell>;
+    const questionsBadge = await prisma.studentQuestion.count({
+      where: {
+        messages: {
+          some: {
+            isRead: false,
+            author: { role: "student" },
+          },
+        },
+      },
+    });
+    return <AdminShell userName={session.user.name} questionsBadge={questionsBadge}>{children}</AdminShell>;
   }
 
   return (
@@ -33,6 +44,7 @@ export default async function CuratorLayout({ children }: { children: React.Reac
         <nav className="flex-1 py-3 space-y-0.5 px-2">
           <NavLink href="/curator/dashboard">Обзор</NavLink>
           <NavLink href="/curator/homework">ДЗ на проверку</NavLink>
+          <NavLink href="/curator/questions">Вопросы</NavLink>
         </nav>
         <div className="px-4 py-4" style={{ borderTop: "1px solid rgba(255,255,255,0.08)" }}>
           <p className="text-xs mb-2 truncate" style={{ color: "#888" }}>{session.user.name}</p>

src/app/curator/questions/page.tsx

@@ -0,0 +1,12 @@
+import { headers } from "next/headers";
+import { auth } from "@/lib/auth";
+import { redirect } from "next/navigation";
+import { QuestionSplitView } from "@/components/questions/QuestionSplitView";
+
+export default async function CuratorQuestionsPage() {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) redirect("/login");
+  if (session.user.role !== "admin" && session.user.role !== "curator") redirect("/dashboard");
+
+  return <QuestionSplitView currentUserId={session.user.id} />;
+}

src/components/admin/admin-nav.tsx

@@ -9,13 +9,14 @@ const links = [
   { href: "/admin/categories", label: "Категории" },
   { href: "/admin/users", label: "Пользователи" },
   { href: "/curator/homework", label: "ДЗ на проверку" },
+  { href: "/admin/questions", label: "Вопросы" },
   { href: "/admin/quizzes", label: "Тесты" },
   { href: "/admin/comments", label: "Комментарии" },
   { href: "/admin/import-export", label: "Импорт / Экспорт" },
   { href: "/admin/settings", label: "Настройки" },
 ];
 
-export function AdminNav() {
+export function AdminNav({ questionsBadge = 0 }: { questionsBadge?: number }) {
   const pathname = usePathname();
 
   return (
@@ -24,7 +25,7 @@ export function AdminNav() {
         const active =
           pathname === href ||
           (href !== "/admin/dashboard" && href !== "/curator/homework" && pathname.startsWith(href)) ||
-          (href === "/curator/homework" && pathname.startsWith("/curator"));
+          (href === "/curator/homework" && pathname.startsWith("/curator/homework"));
         return (
           <Link
             key={href}
@@ -40,7 +41,23 @@ export function AdminNav() {
                 : undefined
             }
           >
-            {label}
+            <span className="flex items-center justify-between w-full">
+              {label}
+              {href === "/admin/questions" && questionsBadge > 0 && (
+                <span
+                  className="ml-2 inline-flex items-center justify-center rounded-full text-xs font-bold leading-none"
+                  style={{
+                    minWidth: "1.25rem",
+                    height: "1.25rem",
+                    padding: "0 0.3rem",
+                    backgroundColor: "var(--destructive)",
+                    color: "#fff",
+                  }}
+                >
+                  {questionsBadge}
+                </span>
+              )}
+            </span>
           </Link>
         );
       })}

src/components/admin/admin-shell.tsx

@@ -4,9 +4,11 @@ import { LogoutButton } from "@/components/layout/logout-button";
 export function AdminShell({
   children,
   userName,
+  questionsBadge = 0,
 }: {
   children: React.ReactNode;
   userName: string;
+  questionsBadge?: number;
 }) {
   return (
     <div className="min-h-screen flex">
@@ -23,7 +25,7 @@ export function AdminShell({
           </p>
         </div>
         <nav className="flex-1 px-2 py-4 space-y-0.5 overflow-y-auto">
-          <AdminNav />
+          <AdminNav questionsBadge={questionsBadge} />
         </nav>
         <div className="px-4 py-4" style={{ borderTop: "2px solid var(--sidebar-border)" }}>
           <p className="text-xs mb-3 truncate" style={{ color: "var(--sidebar-text)" }}>

src/components/questions/QuestionSplitView.tsx

@@ -0,0 +1,375 @@
+"use client";
+
+import { useState, useEffect, useCallback } from "react";
+
+interface FileAttachment {
+  name: string;
+  url: string;
+  size: number;
+}
+
+interface Message {
+  id: string;
+  authorId: string;
+  text: string;
+  files: FileAttachment[] | null;
+  isRead: boolean;
+  createdAt: string;
+  author: { id: string; name: string; role: string };
+}
+
+interface QuestionSummary {
+  id: string;
+  title: string;
+  status: "OPEN" | "CLOSED";
+  unreadCount: number;
+  updatedAt: string;
+  user: { id: string; name: string };
+  course: { id: string; title: string } | null;
+}
+
+interface QuestionDetail {
+  id: string;
+  title: string;
+  status: "OPEN" | "CLOSED";
+  createdAt: string;
+  user: { id: string; name: string };
+  messages: Message[];
+}
+
+function formatDate(iso: string) {
+  return new Date(iso).toLocaleString("ru", {
+    day: "numeric",
+    month: "short",
+    hour: "2-digit",
+    minute: "2-digit",
+  });
+}
+
+function formatFileSize(bytes: number) {
+  if (bytes < 1024) return `${bytes} Б`;
+  if (bytes < 1024 * 1024) return `${Math.round(bytes / 1024)} КБ`;
+  return `${(bytes / 1024 / 1024).toFixed(1)} МБ`;
+}
+
+export function QuestionSplitView({ currentUserId }: { currentUserId: string }) {
+  const [questions, setQuestions] = useState<QuestionSummary[]>([]);
+  const [selectedId, setSelectedId] = useState<string | null>(null);
+  const [detail, setDetail] = useState<QuestionDetail | null>(null);
+  const [tab, setTab] = useState<"open" | "closed">("open");
+  const [replyText, setReplyText] = useState("");
+  const [sending, setSending] = useState(false);
+  const [closing, setClosing] = useState(false);
+  const [error, setError] = useState("");
+  const [listError, setListError] = useState("");
+  const [listLoading, setListLoading] = useState(true);
+
+  const fetchList = useCallback(async () => {
+    setListError("");
+    setListLoading(true);
+    try {
+      const res = await fetch("/api/questions");
+      if (!res.ok) {
+        setListError("Не удалось загрузить вопросы");
+        return;
+      }
+      const data = await res.json();
+      setQuestions(data);
+    } catch {
+      setListError("Не удалось загрузить вопросы");
+    } finally {
+      setListLoading(false);
+    }
+  }, []);
+
+  useEffect(() => {
+    fetchList();
+  }, [fetchList]);
+
+  async function selectQuestion(id: string) {
+    setSelectedId(id);
+    setReplyText("");
+    setError("");
+    const res = await fetch(`/api/questions/${id}`);
+    if (res.ok) {
+      const data = await res.json();
+      setDetail({
+        ...data,
+        messages: data.messages.map((m: Message & { createdAt: string }) => ({
+          ...m,
+          files: m.files as FileAttachment[] | null,
+        })),
+      });
+      fetchList();
+    }
+  }
+
+  async function handleReply() {
+    if (!replyText.trim() || !selectedId) return;
+    setSending(true);
+    setError("");
+    try {
+      const res = await fetch(`/api/questions/${selectedId}/messages`, {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ text: replyText.trim() }),
+      });
+      if (!res.ok) throw new Error("Ошибка отправки");
+      const msg = await res.json();
+      setDetail((prev) =>
+        prev ? { ...prev, messages: [...prev.messages, msg] } : null
+      );
+      setReplyText("");
+      fetchList();
+    } catch {
+      setError("Не удалось отправить ответ");
+    } finally {
+      setSending(false);
+    }
+  }
+
+  async function handleClose() {
+    if (!selectedId) return;
+    setClosing(true);
+    try {
+      const res = await fetch(`/api/questions/${selectedId}/close`, {
+        method: "PATCH",
+      });
+      if (!res.ok) throw new Error("Ошибка закрытия");
+      setDetail((prev) => (prev ? { ...prev, status: "CLOSED" } : null));
+      fetchList();
+    } catch {
+      setError("Не удалось закрыть вопрос");
+    } finally {
+      setClosing(false);
+    }
+  }
+
+  const filtered = questions.filter((q) =>
+    tab === "open" ? q.status === "OPEN" : q.status === "CLOSED"
+  );
+
+  return (
+    <div className="flex h-[calc(100vh-56px)]">
+      {/* Left panel */}
+      <div
+        className="flex flex-col"
+        style={{ width: "45%", borderRight: "2px solid var(--border)" }}
+      >
+        {/* Tabs */}
+        <div className="flex p-2 gap-1" style={{ borderBottom: "1px solid var(--border)" }}>
+          {(["open", "closed"] as const).map((t) => (
+            <button
+              key={t}
+              onClick={() => setTab(t)}
+              className="text-xs px-3 py-1 rounded-sm font-medium"
+              style={
+                tab === t
+                  ? { background: "var(--foreground)", color: "var(--background)" }
+                  : { background: "var(--muted)", color: "var(--muted-foreground)" }
+              }
+            >
+              {t === "open"
+                ? `Открытые ${questions.filter((q) => q.status === "OPEN").length}`
+                : "Закрытые"}
+            </button>
+          ))}
+        </div>
+
+        {/* Question list */}
+        <div className="flex-1 overflow-y-auto">
+          {listError && (
+            <p className="text-xs p-4" style={{ color: "var(--destructive)" }}>
+              {listError}
+            </p>
+          )}
+          {listLoading && (
+            <p className="text-xs p-4" style={{ color: "var(--muted-foreground)" }}>
+              Загрузка...
+            </p>
+          )}
+          {!listLoading && filtered.length === 0 && (
+            <p className="text-xs p-4" style={{ color: "var(--muted-foreground)" }}>
+              Нет вопросов
+            </p>
+          )}
+          {filtered.map((q) => (
+            <button
+              key={q.id}
+              onClick={() => selectQuestion(q.id)}
+              className="w-full text-left p-3 block"
+              style={{
+                borderLeft:
+                  selectedId === q.id
+                    ? "3px solid var(--foreground)"
+                    : "3px solid transparent",
+                borderBottom: "1px solid var(--border)",
+                background:
+                  q.unreadCount > 0
+                    ? "#E8F0D8"
+                    : selectedId === q.id
+                    ? "var(--muted)"
+                    : "transparent",
+              }}
+            >
+              <p className="text-sm font-bold truncate" style={{ color: "var(--foreground)" }}>
+                {q.user.name}
+              </p>
+              <p className="text-xs truncate" style={{ color: "var(--muted-foreground)" }}>
+                {q.title}
+              </p>
+              <p className="text-xs mt-0.5" style={{ color: "#999" }}>
+                {formatDate(q.updatedAt)}
+                {q.unreadCount > 0 && (
+                  <span style={{ color: "#c00", marginLeft: 4 }}>🔴 новое</span>
+                )}
+              </p>
+            </button>
+          ))}
+        </div>
+      </div>
+
+      {/* Right panel */}
+      <div className="flex flex-col overflow-hidden" style={{ width: "55%" }}>
+        {!detail ? (
+          <div className="flex-1 flex items-center justify-center">
+            <p className="text-sm" style={{ color: "var(--muted-foreground)" }}>
+              Выберите вопрос
+            </p>
+          </div>
+        ) : (
+          <>
+            {/* Thread header */}
+            <div
+              className="flex items-start justify-between p-4 shrink-0"
+              style={{ borderBottom: "1px solid var(--border)" }}
+            >
+              <div>
+                <p className="text-sm font-bold" style={{ color: "var(--foreground)" }}>
+                  {detail.title}
+                </p>
+                <p className="text-xs" style={{ color: "var(--muted-foreground)" }}>
+                  {detail.user.name} ·{" "}
+                  {new Date(detail.createdAt).toLocaleDateString("ru", {
+                    day: "numeric",
+                    month: "long",
+                  })}
+                </p>
+              </div>
+              {detail.status === "OPEN" && (
+                <button
+                  onClick={handleClose}
+                  disabled={closing}
+                  className="text-xs px-3 py-1.5 rounded-sm shrink-0"
+                  style={{
+                    background: "var(--muted)",
+                    border: "1px solid var(--border)",
+                    color: "var(--foreground)",
+                  }}
+                >
+                  {closing ? "..." : "✓ Закрыть вопрос"}
+                </button>
+              )}
+            </div>
+
+            {/* Messages */}
+            <div className="flex-1 overflow-y-auto p-4 flex flex-col gap-3">
+              {detail.messages.map((msg) => {
+                const isMine = msg.authorId === currentUserId;
+                return (
+                  <div
+                    key={msg.id}
+                    className="max-w-[85%] px-3 py-2 rounded-sm text-sm"
+                    style={{
+                      alignSelf: isMine ? "flex-end" : "flex-start",
+                      background: isMine ? "var(--muted)" : "var(--background)",
+                      border: isMine ? "none" : "2px solid #E8F0D8",
+                    }}
+                  >
+                    <p className="text-xs mb-1" style={{ color: "var(--muted-foreground)" }}>
+                      {msg.author.name} · {formatDate(msg.createdAt)}
+                    </p>
+                    <p style={{ color: "var(--foreground)" }}>{msg.text}</p>
+                    {msg.files && msg.files.length > 0 && (
+                      <div className="flex flex-col gap-1 mt-2">
+                        {msg.files.map((f) => (
+                          <a
+                            key={f.url}
+                            href={f.url.startsWith("https://") ? f.url : "#"}
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="flex items-center gap-1.5 text-xs px-2 py-1 rounded-sm"
+                            style={{
+                              background: "var(--background)",
+                              border: "1px solid var(--border)",
+                              color: "var(--foreground)",
+                              width: "fit-content",
+                            }}
+                          >
+                            📎 {f.name}
+                            <span style={{ color: "#999" }}>· {formatFileSize(f.size)}</span>
+                          </a>
+                        ))}
+                      </div>
+                    )}
+                  </div>
+                );
+              })}
+            </div>
+
+            {/* Reply form */}
+            <div
+              className="p-3 shrink-0"
+              style={{ borderTop: "1px solid var(--border)" }}
+            >
+              <div
+                className="flex gap-2"
+                style={{ opacity: detail.status === "CLOSED" ? 0.5 : 1 }}
+              >
+                <input
+                  type="text"
+                  value={replyText}
+                  onChange={(e) => setReplyText(e.target.value)}
+                  onKeyDown={(e) => {
+                    if (e.key === "Enter" && !e.shiftKey) {
+                      e.preventDefault();
+                      handleReply();
+                    }
+                  }}
+                  disabled={detail.status === "CLOSED"}
+                  placeholder={
+                    detail.status === "CLOSED" ? "Вопрос закрыт" : "Написать ответ..."
+                  }
+                  className="flex-1 text-sm px-3 py-2 outline-none"
+                  style={{
+                    border: "1px solid var(--border)",
+                    background: "var(--background)",
+                    color: "var(--foreground)",
+                  }}
+                />
+                <button
+                  onClick={handleReply}
+                  disabled={sending || !replyText.trim() || detail.status === "CLOSED"}
+                  className="text-xs font-bold px-4 py-2"
+                  style={{
+                    background: "var(--foreground)",
+                    color: "var(--background)",
+                    border: "none",
+                    opacity: sending ? 0.6 : 1,
+                  }}
+                >
+                  {sending ? "..." : "Отправить"}
+                </button>
+              </div>
+              {error && (
+                <p className="text-xs mt-1" style={{ color: "var(--destructive)" }}>
+                  {error}
+                </p>
+              )}
+            </div>
+          </>
+        )}
+      </div>
+    </div>
+  );
+}

src/components/questions/QuestionThread.tsx

@@ -0,0 +1,262 @@
+"use client";
+
+import { useState, useRef, useEffect } from "react";
+
+interface FileAttachment {
+  name: string;
+  url: string;
+  size: number;
+}
+
+interface Message {
+  id: string;
+  authorId: string;
+  text: string;
+  files: FileAttachment[] | null;
+  isRead: boolean;
+  createdAt: string;
+  author: { id: string; name: string; role: string };
+}
+
+interface QuestionThreadProps {
+  questionId: string;
+  questionStatus: "OPEN" | "CLOSED";
+  currentUserId: string;
+  initialMessages: Message[];
+}
+
+function formatDate(iso: string) {
+  return new Date(iso).toLocaleString("ru", {
+    day: "numeric",
+    month: "long",
+    hour: "2-digit",
+    minute: "2-digit",
+  });
+}
+
+function formatFileSize(bytes: number) {
+  if (bytes < 1024) return `${bytes} B`;
+  if (bytes < 1024 * 1024) return `${Math.round(bytes / 1024)} KB`;
+  return `${(bytes / 1024 / 1024).toFixed(1)} MB`;
+}
+
+export function QuestionThread({
+  questionId,
+  questionStatus,
+  currentUserId,
+  initialMessages,
+}: QuestionThreadProps) {
+  const [messages, setMessages] = useState<Message[]>(initialMessages);
+  const [text, setText] = useState("");
+  const [files, setFiles] = useState<FileAttachment[]>([]);
+  const [uploading, setUploading] = useState(false);
+  const [sending, setSending] = useState(false);
+  const [error, setError] = useState("");
+  const fileInputRef = useRef<HTMLInputElement>(null);
+  const messagesEndRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    messagesEndRef.current?.scrollIntoView({ behavior: "smooth" });
+  }, [messages]);
+
+  async function handleFileSelect(e: React.ChangeEvent<HTMLInputElement>) {
+    const selected = Array.from(e.target.files ?? []);
+    if (!selected.length) return;
+    setUploading(true);
+    setError("");
+
+    try {
+      const uploaded: FileAttachment[] = [];
+      for (const f of selected) {
+        const form = new FormData();
+        form.append("file", f);
+        const res = await fetch("/api/student/question-upload", { method: "POST", body: form });
+        if (!res.ok) {
+          const d = await res.json();
+          throw new Error(d.error ?? "Ошибка загрузки файла");
+        }
+        uploaded.push(await res.json());
+      }
+      setFiles((prev) => [...prev, ...uploaded]);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Ошибка загрузки");
+    } finally {
+      setUploading(false);
+      if (fileInputRef.current) fileInputRef.current.value = "";
+    }
+  }
+
+  async function handleSend() {
+    if (uploading) return;
+    if (!text.trim() && files.length === 0) return;
+    setSending(true);
+    setError("");
+
+    try {
+      const res = await fetch(`/api/questions/${questionId}/messages`, {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ text: text.trim(), files }),
+      });
+      if (!res.ok) {
+        const d = await res.json();
+        throw new Error(d.error ?? "Ошибка отправки");
+      }
+      const msg = await res.json();
+      setMessages((prev) => [...prev, msg]);
+      setText("");
+      setFiles([]);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Ошибка");
+    } finally {
+      setSending(false);
+    }
+  }
+
+  return (
+    <div className="flex flex-col gap-2 w-full">
+      {/* Messages */}
+      <div className="flex flex-col gap-2 mb-4 max-h-96 overflow-y-auto pr-1">
+        {messages.map((msg) => {
+          const isMine = msg.authorId === currentUserId;
+          const isNew = !msg.isRead && !isMine;
+          return (
+            <div
+              key={msg.id}
+              className="max-w-[88%] px-3 py-2 rounded-sm text-sm"
+              style={{
+                alignSelf: isMine ? "flex-end" : "flex-start",
+                background: isMine ? "var(--muted)" : "var(--background)",
+                border: isMine ? "none" : `2px solid #E8F0D8`,
+                borderLeft: !isMine && isNew ? "3px solid #323232" : undefined,
+              }}
+            >
+              <p
+                className="text-xs mb-1"
+                style={{ color: "var(--muted-foreground)" }}
+              >
+                {isMine ? "Ты" : msg.author.name} · {formatDate(msg.createdAt)}
+                {isNew && (
+                  <strong style={{ color: "#323232" }}> · 🔵 новое</strong>
+                )}
+              </p>
+              <p style={{ color: "var(--foreground)" }}>{msg.text}</p>
+              {msg.files && msg.files.length > 0 && (
+                <div className="flex flex-col gap-1 mt-2">
+                  {msg.files.map((f, i) => (
+                    <a
+                      key={i}
+                      href={f.url.startsWith("https://") ? f.url : "#"}
+                      target="_blank"
+                      rel="noreferrer"
+                      className="flex items-center gap-1.5 text-xs px-2 py-1 rounded-sm"
+                      style={{
+                        background: "var(--background)",
+                        border: "1px solid #AAAAAA",
+                        color: "var(--foreground)",
+                        width: "fit-content",
+                      }}
+                    >
+                      📎 <span>{f.name}</span>
+                      <span style={{ color: "#999" }}>· {formatFileSize(f.size)}</span>
+                    </a>
+                  ))}
+                </div>
+              )}
+            </div>
+          );
+        })}
+        <div ref={messagesEndRef} />
+      </div>
+
+      {/* Queued files preview */}
+      {files.length > 0 && (
+        <div className="flex flex-wrap gap-1 mb-2">
+          {files.map((f, i) => (
+            <div
+              key={i}
+              className="flex items-center gap-1 text-xs px-2 py-1 rounded-sm"
+              style={{ background: "var(--color-surface)", border: "1px solid var(--border)" }}
+            >
+              📎 {f.name}
+              <button
+                onClick={() => setFiles((prev) => prev.filter((_, j) => j !== i))}
+                className="ml-1 text-xs"
+                style={{ color: "var(--muted-foreground)" }}
+              >
+                ×
+              </button>
+            </div>
+          ))}
+        </div>
+      )}
+
+      {/* Reply form */}
+      <div
+        className="rounded-sm p-2"
+        style={{
+          border: "2px solid #AAAAAA",
+          background: "var(--color-surface)",
+          opacity: questionStatus === "CLOSED" ? 0.5 : 1,
+          pointerEvents: questionStatus === "CLOSED" ? "none" : "auto",
+        }}
+      >
+        <textarea
+          value={text}
+          onChange={(e) => setText(e.target.value)}
+          placeholder={questionStatus === "CLOSED" ? "Вопрос закрыт" : "Написать сообщение..."}
+          rows={3}
+          disabled={questionStatus === "CLOSED"}
+          className="w-full text-sm outline-none resize-none bg-transparent"
+          style={{ border: "none", color: "var(--foreground)" }}
+        />
+        <div
+          className="flex items-center justify-between pt-2 mt-1"
+          style={{ borderTop: "1px solid var(--muted)" }}
+        >
+          <div className="flex items-center gap-2">
+            <input
+              ref={fileInputRef}
+              type="file"
+              multiple
+              accept=".jpg,.jpeg,.png,.pdf,.md,.txt"
+              className="hidden"
+              onChange={handleFileSelect}
+            />
+            <button
+              type="button"
+              onClick={() => fileInputRef.current?.click()}
+              disabled={uploading}
+              className="text-xs px-2 py-1 rounded-sm"
+              style={{ background: "var(--color-surface)", border: "1px solid #AAAAAA" }}
+            >
+              {uploading ? "Загрузка..." : "📎 Прикрепить"}
+            </button>
+            <span className="text-xs" style={{ color: "#999" }}>
+              jpg, png, pdf, md · до 10 МБ
+            </span>
+          </div>
+          <button
+            type="button"
+            onClick={handleSend}
+            disabled={sending || (!text.trim() && files.length === 0)}
+            className="text-xs font-bold px-4 py-1.5 rounded-sm"
+            style={{
+              background: "var(--foreground)",
+              color: "var(--background)",
+              border: "none",
+              opacity: sending ? 0.6 : 1,
+            }}
+          >
+            {sending ? "..." : "Отправить →"}
+          </button>
+        </div>
+        {error && (
+          <p className="text-xs mt-1" style={{ color: "var(--destructive)" }}>
+            {error}
+          </p>
+        )}
+      </div>
+    </div>
+  );
+}

src/lib/email.ts

@@ -190,6 +190,29 @@ export async function sendTestEmail(to: string) {
   }).catch((e) => console.error("[email] sendTestEmail:", e));
 }
 
+export async function sendAccessEmail(
+  to: string,
+  name: string,
+  courseTitle: string,
+  tempPassword: string
+) {
+  const school = await getSchoolName();
+  await getResend().emails.send({
+    from: FROM,
+    to,
+    subject: `Доступ к курсу «${courseTitle}» открыт`,
+    html: base(`
+      <p ${p}>Привет!</p>
+      <p ${p}>Вам открыт доступ к курсу <strong>«${courseTitle}»</strong> на образовательной платформе <strong>${school}</strong>.</p>
+      <p ${p}>Ваши данные для входа:</p>
+      ${quote(`Логин: ${to}\nПароль: ${tempPassword}`)}
+      <p ${p}>После входа рекомендуем сразу сменить пароль в разделе «Профиль».</p>
+      <p ${pLast}>Если пароль не подходит — воспользуйтесь ссылкой «Забыли пароль?» на странице входа.</p>
+      ${btn(`${BASE_URL}/login`, "Войти на платформу")}
+    `, school),
+  }).catch((e) => console.error("[email] sendAccessEmail:", e));
+}
+
 export async function sendPasswordResetEmail(to: string, name: string, resetUrl: string) {
   const school = await getSchoolName();
   await getResend().emails.send({
@@ -205,3 +228,87 @@ export async function sendPasswordResetEmail(to: string, name: string, resetUrl:
     `, school),
   }).catch((e) => console.error("[email] sendPasswordResetEmail:", e));
 }
+
+export async function sendQuestionCreatedEmail(
+  to: string,
+  recipientName: string,
+  studentName: string,
+  questionTitle: string,
+) {
+  const school = await getSchoolName();
+  await getResend().emails.send({
+    from: FROM,
+    to,
+    subject: `Новый вопрос от ${studentName}`,
+    html: base(`
+      <p ${p}>Привет, ${recipientName}!</p>
+      <p ${p}>Студент <strong>${studentName}</strong> задал новый вопрос:</p>
+      ${quote(questionTitle)}
+      <p ${pLast}>Откройте панель, чтобы ответить:</p>
+      ${btn(`${BASE_URL}/admin/questions`, "Перейти к вопросам")}
+    `, school),
+  }).catch((e) => console.error("[email] sendQuestionCreatedEmail:", e));
+}
+
+export async function sendQuestionReplyEmail(
+  to: string,
+  studentName: string,
+  questionTitle: string,
+  questionId: string,
+) {
+  const school = await getSchoolName();
+  await getResend().emails.send({
+    from: FROM,
+    to,
+    subject: `Ответ на ваш вопрос`,
+    html: base(`
+      <p ${p}>Привет, ${studentName}!</p>
+      <p ${p}>Школа ответила на ваш вопрос:</p>
+      ${quote(questionTitle)}
+      <p ${pLast}>Откройте тред чтобы прочитать ответ:</p>
+      ${btn(`${BASE_URL}/questions/${questionId}`, "Читать ответ")}
+    `, school),
+  }).catch((e) => console.error("[email] sendQuestionReplyEmail:", e));
+}
+
+export async function sendQuestionFollowUpEmail(
+  to: string,
+  recipientName: string,
+  studentName: string,
+  questionTitle: string,
+) {
+  const school = await getSchoolName();
+  await getResend().emails.send({
+    from: FROM,
+    to,
+    subject: `Новый ответ от студента — ${questionTitle}`,
+    html: base(`
+      <p ${p}>Привет, ${recipientName}!</p>
+      <p ${p}>Студент <strong>${studentName}</strong> добавил сообщение в вопрос:</p>
+      ${quote(questionTitle)}
+      <p ${pLast}>Откройте панель, чтобы ответить:</p>
+      ${btn(`${BASE_URL}/admin/questions`, "Перейти к вопросам")}
+    `, school),
+  }).catch((e) => console.error("[email] sendQuestionFollowUpEmail:", e));
+}
+
+export async function sendHomeworkUpdatedEmail(
+  to: string,
+  recipientName: string,
+  studentName: string,
+  lessonTitle: string,
+  submissionId: string,
+) {
+  const school = await getSchoolName();
+  await getResend().emails.send({
+    from: FROM,
+    to,
+    subject: `Студент обновил работу — ${lessonTitle}`,
+    html: base(`
+      <p ${p}>Привет, ${recipientName}!</p>
+      <p ${p}>Студент <strong>${studentName}</strong> обновил работу по уроку <strong>«${lessonTitle}»</strong>.</p>
+      <p ${pLast}>Откройте работу чтобы проверить изменения:</p>
+      ${btn(`${BASE_URL}/curator/homework/${submissionId}`, "Открыть работу")}
+    `, school),
+  }).catch((e) => console.error("[email] sendHomeworkUpdatedEmail:", e));
+}