/**
 * Trading Studio PWA Service Worker（轻量版）
 * 仅处理导航请求，不拦截 Gradio 静态资源 — 避免平板端加载变慢。
 */
const CACHE_NAME = "trading-studio-v2";

self.addEventListener("install", (event) => {
  self.skipWaiting();
});

self.addEventListener("activate", (event) => {
  event.waitUntil(
    caches.keys().then((keys) =>
      Promise.all(keys.filter((k) => k !== CACHE_NAME).map((k) => caches.delete(k)))
    )
  );
  self.clients.claim();
});

self.addEventListener("fetch", (event) => {
  const { request } = event;

  // 仅缓存页面导航，Gradio JS/CSS/API 全部直连网络
  if (request.method !== "GET" || request.mode !== "navigate") {
    return;
  }

  event.respondWith(
    fetch(request).catch(() => caches.match("/"))
  );
});