Next.js Route Handler with auth guard

                  import { NextResponse } from 'next/server';
import { z } from 'zod';

const Body = z.object({ name: z.string().min(2).max(80) });

function getUserId(req: Request) {
  const auth = req.headers.get('authorization');
  if (!auth?.startsWith('Bearer ')) return null;
  return auth.slice('Bearer '.length);
}

export async function POST(req: Request) {
  const userId = getUserId(req);
  if (!userId) return NextResponse.json({ error: 'UNAUTHORIZED' }, { status: 401 });

  const json = await req.json();
  const parsed = Body.safeParse(json);
  if (!parsed.success) {
    return NextResponse.json(
      { error: 'VALIDATION_ERROR', issues: parsed.error.issues },
      { status: 400 }
    );
  }

  const created = { id: crypto.randomUUID?.() ?? 'temp', name: parsed.data.name, ownerId: userId };
  return NextResponse.json(created, { status: 201 });
}