const cacheName = 'spa-cache-v1';

// —— Cache pressure controls ——
const MAX_NOHASH_ENTRIES = 500; // 每个无 hash 版本缓存的最大条目数
const MAX_HASH_ENTRIES = 200; // 带 hash 静态资源缓存最大条目数
const MAX_IMG_RESPONSE_SIZE = 1_500_000; // 超过此大小（字节）不入缓存
// iOS/Safari 下调限额（小容量设备）
const IS_SAFARI = /Safari\//.test(self.navigator.userAgent) && !/Chrome\//.test(self.navigator.userAgent);
const IS_FB_BROWSER = /FBAN|FBAV|FB_IAB/i.test(self.navigator.userAgent);
const IOS_LIMIT_FACTOR = IS_SAFARI ? 0.5 : 1;
const FB_LIMIT_FACTOR = IS_FB_BROWSER ? 0.3 : 1;
const DEVICE_FACTOR = Math.min(IOS_LIMIT_FACTOR, FB_LIMIT_FACTOR);

// —— Image cache configs ——
const IMG_NOHASH_CACHE_PREFIX = 'img-webp-nohash-v'; // versioned
const IMG_HASH_CACHE_NAME = 'img-webp-hash'; // stable (hashed filenames)
let IMG_VERSION = '0';

async function readAppVersion() {
  try {
    const res = await fetch('/app_version.json', { cache: 'no-store' });
    if (res && res.ok) {
      const data = await res.json();
      IMG_VERSION = String(data?.version || '0');
    }
  } catch (e) {
    // ignore
  }
}

// —— Cookie Store 安全封装（iOS Safari 可能不支持） ——
function hasCookieStore() {
  return 'cookieStore' in self && self.cookieStore && typeof self.cookieStore.get === 'function';
}

async function safeGetCookie(name) {
  if (!hasCookieStore()) return undefined;
  try {
    const res = await self.cookieStore.get(name);
    return res?.value;
  } catch (e) {
    return undefined;
  }
}

async function safeSetCookie(name, value) {
  if (!hasCookieStore()) return;
  try {
    await self.cookieStore.set(name, value);
  } catch (e) {
    // ignore
  }
}

async function safeDeleteCookie(name) {
  if (!hasCookieStore()) return;
  try {
    await self.cookieStore.delete(name);
  } catch (e) {
    // ignore
  }
}

// 定义主域名和备用域名列表
var BACKUP_DOMAINS = ['https://winus777.com'];
// 当前选定的域名
let activeDomain = '';
var ORIGINAL_DOMAIN;

// 安装 Service Worker 并缓存 index.html
self.addEventListener('install', function (e) {
  e.waitUntil(
    (async () => {
      await readAppVersion();
      const cache = await caches.open(cacheName);
      let ok;
      try {
        ORIGINAL_DOMAIN = await safeGetCookie('ORIGINAL_DOMAIN');
        ok = await cache.addAll([
          // '/index.html'
        ]);
      } catch (err) {
        console.log('err: cache.addAll');
      }
      return ok;
    })()
  );
  console.log('[Service Worker] Install');
  self.skipWaiting();
});

self.addEventListener('activate', e => {
  // Remove unwanted caches
  e.waitUntil(
    (async () => {
      await readAppVersion();
      ORIGINAL_DOMAIN = await safeGetCookie('ORIGINAL_DOMAIN');
      const names = await caches.keys();
      const validNoHashName = IMG_NOHASH_CACHE_PREFIX + IMG_VERSION;
      await Promise.all(
        names.map(name => {
          const isOldNoHash = name.startsWith(IMG_NOHASH_CACHE_PREFIX) && name !== validNoHashName;
          const isOldSpa = name !== cacheName && !name.startsWith(IMG_NOHASH_CACHE_PREFIX) && name !== IMG_HASH_CACHE_NAME;
          if (isOldNoHash || isOldSpa) {
            console.log('Service Worker: Clearing Old Cache', name);
            return caches.delete(name);
          }
        })
      );
      await self.clients.claim();
    })()
  );
});
self.addEventListener('fetch', event => {
  const request = event.request;
  const url = new URL(request.url);

  // 仅处理同源请求
  const isSameOrigin = url.origin === self.location.origin;

  // 1) 导航请求：沿用现有逻辑
  if (request.mode === 'navigate') {
    event.respondWith(handleRequest(request, url));
    return;
  }

  // 2) 仅处理 .webp 图片
  const isWebpImage = request.destination === 'image' && /\.webp(\?|$)/.test(url.pathname);
  if (!isWebpImage || !isSameOrigin) {
    return; // 放过其余请求
  }

  const isNoHashDir = url.pathname.startsWith('/game_data/') || url.pathname.startsWith('/img/');

  // 2.1 无 hash 目录：Stale-While-Revalidate，版本化缓存名
  if (isNoHashDir) {
    const noHashCacheName = IMG_NOHASH_CACHE_PREFIX + IMG_VERSION;
    event.respondWith(
      (async () => {
        const cache = await caches.open(noHashCacheName);
        const cached = await cache.match(request);
        const networkPromise = fetch(request)
          .then(resp => {
            if (resp && resp.ok) {
              const len = Number(resp.headers.get('content-length') || '0');
              if (len === 0 || len <= MAX_IMG_RESPONSE_SIZE) {
                cache.put(request, resp.clone());
                // 限制缓存条数，删除最早的
                enforceCacheLimit(noHashCacheName, Math.floor(MAX_NOHASH_ENTRIES * DEVICE_FACTOR));
              }
            }
            return resp;
          })
          .catch(() => cached); // 网络失败时回退缓存

        if (cached) {
          event.waitUntil(networkPromise); // 背景更新
          return cached;
        }
        return networkPromise;
      })()
    );
    return;
  }

  // 2.2 其他（带 hash）：Cache-First
  event.respondWith(
    (async () => {
      const cache = await caches.open(IMG_HASH_CACHE_NAME);
      const cached = await cache.match(request);
      if (cached) return cached;
      const resp = await fetch(request);
      if (resp && resp.ok) {
        const len = Number(resp.headers.get('content-length') || '0');
        if (len === 0 || len <= MAX_IMG_RESPONSE_SIZE) {
          cache.put(request, resp.clone());
          enforceCacheLimit(IMG_HASH_CACHE_NAME, Math.floor(MAX_HASH_ENTRIES * DEVICE_FACTOR));
        }
      }
      return resp;
    })()
  );
});

async function handleRequest(request, url) {
  const cachedResponse = await caches.match(request);
  const originalDomain = await safeGetCookie('ORIGINAL_DOMAIN');
  try {
    // 如果缓存中有匹配，则继续请求网络，并更新缓存
    return await fetchAndUpdateCache(request, originalDomain, url);
  } catch (err) {
    if (cachedResponse) {
      return cachedResponse;
    }
    try {
      return await fetch(request);
    } catch (e2) {
      return new Response('Service Worker Error', { status: 500 });
    }
  }
}

async function enforceCacheLimit(cacheName, maxEntries) {
  try {
    const cache = await caches.open(cacheName);
    const keys = await cache.keys();
    const over = keys.length - maxEntries;
    if (over > 0) {
      for (let i = 0; i < over; i++) {
        await cache.delete(keys[i]); // 近似 LRU：按插入顺序清理最早的
      }
    }
  } catch (e) {
    // ignore
  }
}

async function fetchAndUpdateCache(request, ORIGINAL_DOMAIN, url) {
  try {
    const networkResponse = await fetch(request);
    if (ORIGINAL_DOMAIN && ORIGINAL_DOMAIN !== url.origin && url.origin === self.location.origin) {
      await safeDeleteCookie('ORIGINAL_DOMAIN');
    }
    return networkResponse;
  } catch (err) {
    return await handleBackupDomain(request, ORIGINAL_DOMAIN, url);
  }
}

async function handleBackupDomain(request, ORIGINAL_DOMAIN, url) {
  if (ORIGINAL_DOMAIN && ORIGINAL_DOMAIN !== url.origin && url.origin === self.location.origin) {
    const backupResponse = await judgeActiveDomain(ORIGINAL_DOMAIN, request);
    if (backupResponse) return backupResponse;
  }

  return await fetchFromBackup(request);
}

async function fetchFromBackup(request) {
  for (let domain of BACKUP_DOMAINS) {
    const response = await judgeActiveDomain(domain, request);
    if (response) return response;
  }
  // return await fetchFromLatestBackupAddress(request);
}

async function judgeActiveDomain(url, originalRequest) {
  try {
    const newUrl = originalRequest.url.replace(self.location.origin, url);
    const newRequest = new Request(newUrl);
    const response = await fetch(newRequest);
    if (response.ok) {
      // 成功从备用域名获取资源，更新 activeDomain，将请求的html 存入缓存
      await safeSetCookie('ORIGINAL_DOMAIN', url);

      // 刷新界面
      return response.text().then(body => {
        // 定义路径前缀映射表
        const pathReplacements = {
          '/js': `${url}/js`,
          '/css': `${url}/css`,
          '/favicon': `${url}/favicon`,
          '/cdn': `${url}/cdn`,
          '/img': `${url}/img`,
          '/manifest': `${url}/product/manifest`
        };

        // 动态替换规则
        let newBody = body;
        for (const [prefix, replacement] of Object.entries(pathReplacements)) {
          const regex = new RegExp(`(src|href)="${prefix}`, 'g');
          newBody = newBody.replace(regex, `$1="${replacement}`);
        }
        newBody = newBody.replace(/src="\.\//g, `src="${url}/`);
        newBody = newBody.replace(/href="\.\//g, `href="${url}/`);
        return new Response(newBody, {
          headers: response.headers
        });
      });
    } else {
      console.log(`Backup domain ${url} returned status: ${response.status}`);
    }
  } catch (error) {
    console.log(`Backup domain ${url} failed:`, error);
  }
}

self.addEventListener('push', function (event) {
  if (event.data) {
    var notificationData = event.data.json();
    var title = notificationData.title;
    var imageSmall = notificationData.imageSmall;
    var imageLarge = notificationData.imageLarge;
    // 跳转地址
    var url = notificationData.url;
    var actions = notificationData.actions;

    var options = {
      body: notificationData.body || notificationData.message,
      icon: imageSmall,
      image: imageLarge,
      badge: imageSmall,
      actions: actions,
      data: {
        url: url
      }
    };

    event.waitUntil(self.registration.showNotification(title, options));
  }
});

// 处理点击消息
self.addEventListener('notificationclick', function (event) {
  event.notification.close(); // 关闭推送通知
  // 获取推送通知的数据
  var notificationData = event.notification.data;
  // 获取要跳转的页面链接
  var targetPage = notificationData.url; // 假设推送通知的数据中包含了要跳转的页面链接
  // 执行页面跳转操作
  event.waitUntil(clients.openWindow(targetPage));
});