Add deck generation and study flow improvements

src/app/api/spaced-repetition-sets/route.ts

@@ -0,0 +1,30 @@
+import { NextRequest, NextResponse } from "next/server";
+import { createSpacedRepetitionSetSchema } from "@/lib/validation/spacedRepetitionSchemas";
+import { spacedRepetitionErrorResponse } from "@/lib/spacedRepetitionApi";
+import * as spacedRepetitionService from "@/services/spacedRepetitionService";
+
+export async function GET(request: NextRequest) {
+  const classId = new URL(request.url).searchParams.get("classId");
+  if (!classId) return NextResponse.json({ error: "classId is required" }, { status: 400 });
+  try {
+    return NextResponse.json(await spacedRepetitionService.listSetsByClass(classId));
+  } catch (error) {
+    return spacedRepetitionErrorResponse(error);
+  }
+}
+
+export async function POST(request: NextRequest) {
+  const parsed = createSpacedRepetitionSetSchema.safeParse(
+    await request.json().catch(() => null)
+  );
+  if (!parsed.success) {
+    return NextResponse.json({ error: "Invalid repetition set" }, { status: 400 });
+  }
+  try {
+    return NextResponse.json(await spacedRepetitionService.createSet(parsed.data), {
+      status: 201,
+    });
+  } catch (error) {
+    return spacedRepetitionErrorResponse(error);
+  }
+}