Add coverImage poster to player, fix TipTap v3 editor reset, quiz admin preview

- Add coverImage field to Lesson model (prisma)
- Pass coverImage as poster prop to KinescopePlayer
- Show quiz in read-only preview mode for admin on lesson page
- Fix TipTap v3 editor reset on save: pass [lesson.id] as deps to useEditor
  to prevent setOptions() from reinitializing content on every re-render
- Replace saveLesson Server Action call with fetch PATCH /api/admin/lessons/[id]
  to avoid Next.js 16 automatic RSC refresh after Server Actions
- Simplify revalidatePath: only revalidate module page, not lesson editor page

prisma/schema.prisma

@@ -130,6 +130,7 @@ model Lesson {
   title       String
   content     Json?
   kinescopeId String?
+  coverImage  String?
   order       Int      @default(0)
   published   Boolean  @default(false)
   createdAt   DateTime @default(now())

src/app/(student)/courses/[slug]/lessons/[lessonId]/page.tsx

@@ -113,7 +113,7 @@ export default async function LessonPage({ params }: Props) {
       {/* Video */}
       {lesson.kinescopeId && (
         <div className="mb-8">
-          <KinescopePlayer videoId={lesson.kinescopeId} />
+          <KinescopePlayer videoId={lesson.kinescopeId} poster={lesson.coverImage ?? undefined} />
         </div>
       )}
 
@@ -180,17 +180,30 @@ export default async function LessonPage({ params }: Props) {
       )}
 
       {/* Quiz */}
-      {lesson.quiz && !isAdmin && (
+      {lesson.quiz && (
         <div className="mb-8">
           <p className="text-xs font-bold uppercase tracking-widest mb-3" style={{ color: "var(--muted-foreground)" }}>
-            Тест
+            Тест{isAdmin && <span className="ml-2 opacity-50">(предпросмотр)</span>}
           </p>
+          {isAdmin ? (
+            <div className="space-y-4 opacity-70">
+              {lesson.quiz.questions.map((q, idx) => (
+                <div key={q.id} className="space-y-1">
+                  <p className="text-sm font-medium">{idx + 1}. {q.text}</p>
+                  <div className="px-4 py-3 text-sm" style={{ border: "2px solid var(--border)", color: "var(--muted-foreground)" }}>
+                    Поле для ответа студента
+                  </div>
+                </div>
+              ))}
+            </div>
+          ) : (
             <QuizSection
               quiz={lesson.quiz}
               attempt={quizAttempt ? { answers: quizAttempt.answers as Record<string, string> } : null}
               slug={slug}
               lessonId={lessonId}
             />
+          )}
         </div>
       )}
 

src/app/api/admin/lessons/[lessonId]/route.ts

@@ -0,0 +1,34 @@
+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<{ lessonId: string }> }
+) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session || session.user.role !== "admin") {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+
+  const { lessonId } = await params;
+  const body = await req.json() as {
+    title: string;
+    kinescopeId: string;
+    content: object;
+    published: boolean;
+  };
+
+  await prisma.lesson.update({
+    where: { id: lessonId },
+    data: {
+      title: body.title,
+      kinescopeId: body.kinescopeId || null,
+      content: body.content,
+      published: body.published,
+    },
+  });
+
+  return NextResponse.json({ ok: true });
+}

src/components/admin/lesson-editor.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useState, useCallback, useTransition } from "react";
+import { useState, useCallback } from "react";
 import { useEditor, EditorContent } from "@tiptap/react";
 import StarterKit from "@tiptap/starter-kit";
 import Image from "@tiptap/extension-image";
@@ -9,7 +9,6 @@ import Underline from "@tiptap/extension-underline";
 import Placeholder from "@tiptap/extension-placeholder";
 import { Save, Eye, FileUp, ChevronLeft, ChevronRight } from "lucide-react";
 import { useRouter } from "next/navigation";
-import { saveLesson } from "@/lib/actions/lesson-actions";
 
 interface LessonData {
   id: string;
@@ -47,7 +46,8 @@ export function LessonEditor({
   const [importing, setImporting] = useState(false);
   const [importError, setImportError] = useState<string | null>(null);
   const [saved, setSaved] = useState(false);
-  const [pending, startTransition] = useTransition();
+  const [saveError, setSaveError] = useState<string | null>(null);
+  const [pending, setPending] = useState(false);
 
   const inputStyle = {
     border: "2px solid var(--border)",
@@ -73,7 +73,7 @@ export function LessonEditor({
         class: "prose prose-slate max-w-none min-h-[300px] focus:outline-none p-4",
       },
     },
-  });
+  }, [lesson.id]);
 
   const uploadImage = useCallback(async () => {
     const input = document.createElement("input");
@@ -133,18 +133,27 @@ export function LessonEditor({
     }
   }, [editor]);
 
-  function handleSave() {
+  async function handleSave() {
     if (!editor) return;
-    startTransition(async () => {
+    setPending(true);
-      await saveLesson(lesson.id, courseId, moduleId, {
+    setSaveError(null);
-        title,
+    try {
-        kinescopeId,
+      const res = await fetch(`/api/admin/lessons/${lesson.id}`, {
-        content: editor.getJSON(),
+        method: "PATCH",
-        published,
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ title, kinescopeId, content: editor.getJSON(), published }),
       });
+      if (!res.ok) {
+        const data = await res.json().catch(() => ({}));
+        throw new Error((data as { error?: string }).error ?? `HTTP ${res.status}`);
+      }
       setSaved(true);
       setTimeout(() => setSaved(false), 2000);
-    });
+    } catch (err) {
+      setSaveError(err instanceof Error ? err.message : "Ошибка сохранения");
+    } finally {
+      setPending(false);
+    }
   }
 
   function navigateTo(lessonId: string) {
@@ -266,6 +275,12 @@ export function LessonEditor({
         </p>
       )}
 
+      {saveError && (
+        <p className="text-xs px-3 py-2" style={{ background: "oklch(0.577 0.245 27.325 / 0.1)", color: "oklch(0.577 0.245 27.325)", border: "1px solid oklch(0.577 0.245 27.325 / 0.3)" }}>
+          Ошибка сохранения: {saveError}
+        </p>
+      )}
+
       {/* Title */}
       <div className="space-y-1">
         <label className="text-xs font-bold uppercase tracking-widest" style={{ color: "var(--muted-foreground)" }}>

src/components/player/kinescope-player.tsx

@@ -4,15 +4,17 @@ import KinescopeReactPlayer from "@kinescope/react-kinescope-player";
 
 interface Props {
   videoId: string;
+  poster?: string;
 }
 
-export function KinescopePlayer({ videoId }: Props) {
+export function KinescopePlayer({ videoId, poster }: Props) {
   return (
     <div className="w-full aspect-video" style={{ border: "2px solid var(--border)" }}>
       <KinescopeReactPlayer
         videoId={videoId}
         width="100%"
         height="100%"
+        poster={poster}
       />
     </div>
   );

src/lib/actions/lesson-actions.ts

@@ -21,7 +21,15 @@ export async function saveLesson(
     published: boolean;
   }
 ) {
+  console.log("[saveLesson] start", lessonId);
+  try {
     await requireAdmin();
+    console.log("[saveLesson] auth ok");
+  } catch (e) {
+    console.error("[saveLesson] auth failed:", e);
+    throw e;
+  }
+  try {
     await prisma.lesson.update({
       where: { id: lessonId },
       data: {
@@ -31,6 +39,11 @@ export async function saveLesson(
         published: data.published,
       },
     });
+    console.log("[saveLesson] db update ok");
+  } catch (e) {
+    console.error("[saveLesson] db update failed:", e);
+    throw e;
+  }
   revalidatePath(`/admin/courses/${courseId}/modules/${moduleId}`);
-  revalidatePath(`/admin/courses/${courseId}/modules/${moduleId}/lessons/${lessonId}`);
+  console.log("[saveLesson] done");
 }