import type { ApiErrorBody } from './types.ts';

/** 类型化 fetch 封装：非 2xx 抛 Error(后端 detail.message)。 */
export async function api<T = unknown>(method: string, url: string, body?: unknown): Promise<T> {
  const headers: Record<string, string> = {};
  const opt: RequestInit = { method, headers };
  if (body !== undefined) {
    headers['Content-Type'] = 'application/json';
    opt.body = JSON.stringify(body);
  }
  const r = await fetch(url, opt);
  const data = (await r.json().catch(() => ({}))) as T & ApiErrorBody;
  if (!r.ok) {
    const detail = data.detail;
    const msg = typeof detail === 'string' ? detail : detail && detail.message;
    throw new Error(msg || String(r.status));
  }
  return data as T;
}