// server/api/polls/[id].ts
export default defineEventHandler(async (event) => {
    const method = event.node.req.method;
    const pollId = getRouterParam(event, 'id');

    // We use Nitro's built-in storage. 
    // 'polls' is the storage namespace.
    const storage = useStorage('polls'); 

    if (!pollId) {
        throw createError({ statusCode: 400, statusMessage: 'Poll ID required' });
    }

    // GET: Fetch the saved Yjs document state
    if (method === 'GET') {
        const data = await storage.getItem(`poll:${pollId}`);
        // Return the array of numbers (or null if it doesn't exist yet)
        return { update: data || null };
    }

    // POST: Save a new Yjs document state
    if (method === 'POST') {
        const body = await readBody(event);

        if (body.update && Array.isArray(body.update)) {
            // Save the binary update (sent as an array of numbers) to storage
            await storage.setItem(`poll:${pollId}`, body.update);
            return { success: true };
        }

        throw createError({ statusCode: 400, statusMessage: 'Invalid update payload' });
    }
});