import type { SimulationFunction } from '@x12i/api-simulator';
import { listBooks } from '../state/checkout-ledger.js';

/**
 * GET /books/search?author=&available=
 *
 * `relative` behavior can only echo data back verbatim -- it has no concept of
 * conditionals. Filtering by query parameters needs a `simulation` handler.
 */
export const searchBooks: SimulationFunction = ({ request }) => {
  const author =
    typeof request.query.author === 'string' ? request.query.author.toLowerCase() : undefined;
  const onlyAvailable = request.query.available === 'true';

  const items = listBooks().filter((book) => {
    if (author && !String(book.author).toLowerCase().includes(author)) return false;
    if (onlyAvailable && Number(book.copiesAvailable) < 1) return false;
    return true;
  });

  return { status: 200, body: { count: items.length, items } };
};