feat(extension): integrate local video info API (#67)

* feat(extension): integrate local video info API

* chore(repo): clean up popup styles

* feat(extension): revamp popup UI

* chore(repo): revert docs and drop content script

extension/entrypoints/background.ts

@@ -0,0 +1,203 @@
+type VideoFormat = {
+  format_id?: string
+  ext?: string
+  format_note?: string
+  resolution?: string
+  width?: number
+  height?: number
+  fps?: number
+  vcodec?: string
+  acodec?: string
+  filesize?: number
+  filesize_approx?: number
+  tbr?: number
+}
+
+type VideoInfo = {
+  title?: string
+  thumbnail?: string
+  duration?: number
+  formats?: VideoFormat[]
+}
+
+type VideoInfoCacheEntry = {
+  url: string
+  status: 'pending' | 'ready' | 'error'
+  fetchedAt: number
+  info?: VideoInfo
+  error?: string
+}
+
+const PORT_RANGE_START = 27100
+const PORT_RANGE_END = 27120
+const STATUS_TIMEOUT_MS = 800
+const INFO_TIMEOUT_MS = 60000
+const CACHE_TTL_MS = 5 * 60 * 1000
+
+const pendingRequests = new Map<string, Promise<void>>()
+const defaultIconPaths = {
+  16: 'icon/16.png',
+  32: 'icon/32.png',
+  48: 'icon/48.png',
+  128: 'icon/128.png'
+}
+const loadingIconPaths = {
+  16: 'icon/icon-loading-16.png',
+  32: 'icon/icon-loading-32.png',
+  48: 'icon/icon-loading-48.png',
+  128: 'icon/icon-loading-128.png'
+}
+const successIconPaths = {
+  16: 'icon/icon-success-16.png',
+  32: 'icon/icon-success-32.png',
+  48: 'icon/icon-success-48.png',
+  128: 'icon/icon-success-128.png'
+}
+
+const setActionIcon = (status: 'default' | 'loading' | 'success', tabId?: number): void => {
+  const paths =
+    status === 'loading'
+      ? loadingIconPaths
+      : status === 'success'
+        ? successIconPaths
+        : defaultIconPaths
+  const options = tabId ? { path: paths, tabId } : { path: paths }
+  void browser.action.setIcon(options)
+}
+
+const fetchJson = async <T>(url: string, timeoutMs: number): Promise<T> => {
+  const controller = new AbortController()
+  const timeoutId = setTimeout(() => controller.abort('timeout'), timeoutMs)
+
+  try {
+    const response = await fetch(url, { signal: controller.signal })
+    const data = (await response.json().catch(() => null)) as (T & { error?: string }) | null
+    if (!response.ok) {
+      const message = data && typeof data === 'object' && 'error' in data ? data.error : null
+      const details = data && typeof data === 'object' && 'details' in data ? data.details : null
+      const combined = [message, details].filter(Boolean).join('\n\n')
+      throw new Error(combined || `Request failed: ${response.status}`)
+    }
+    return data as T
+  } catch (error) {
+    if (error instanceof DOMException && error.name === 'AbortError') {
+      throw new Error('Request timed out.')
+    }
+    if (error instanceof Error && error.message.includes('signal is aborted')) {
+      throw new Error('Request timed out.')
+    }
+    if (error instanceof Error && error.message.includes('Failed to fetch')) {
+      throw new Error('VidBee app not responding on this port.')
+    }
+    throw error
+  } finally {
+    clearTimeout(timeoutId)
+  }
+}
+
+const findAvailablePort = async (): Promise<number | null> => {
+  for (let port = PORT_RANGE_START; port <= PORT_RANGE_END; port += 1) {
+    const baseUrl = `http://127.0.0.1:${port}`
+    try {
+      await fetchJson<{ ok: boolean }>(`${baseUrl}/status`, STATUS_TIMEOUT_MS)
+      return port
+    } catch {
+      // Keep scanning.
+    }
+  }
+  return null
+}
+
+const requestVideoInfo = async (targetUrl: string): Promise<VideoInfo> => {
+  const port = await findAvailablePort()
+  if (!port) {
+    throw new Error('VidBee app not found on localhost.')
+  }
+
+  const baseUrl = `http://127.0.0.1:${port}`
+  const tokenResponse = await fetchJson<{ token?: string }>(`${baseUrl}/token`, STATUS_TIMEOUT_MS)
+  if (!tokenResponse.token) {
+    throw new Error('Failed to acquire token from VidBee.')
+  }
+
+  return fetchJson<VideoInfo>(
+    `${baseUrl}/video-info?url=${encodeURIComponent(targetUrl)}&token=${encodeURIComponent(
+      tokenResponse.token
+    )}`,
+    INFO_TIMEOUT_MS
+  )
+}
+
+const getCacheMap = async (): Promise<Record<string, VideoInfoCacheEntry>> => {
+  const data = await browser.storage.local.get('videoInfoCacheByUrl')
+  const map = data.videoInfoCacheByUrl as Record<string, VideoInfoCacheEntry> | undefined
+  if (!map) return {}
+  return map
+}
+
+const pruneCache = (map: Record<string, VideoInfoCacheEntry>): void => {
+  const now = Date.now()
+  for (const [key, entry] of Object.entries(map)) {
+    if (now - entry.fetchedAt > CACHE_TTL_MS) {
+      delete map[key]
+    }
+  }
+}
+
+const loadCache = async (url: string): Promise<VideoInfoCacheEntry | null> => {
+  const map = await getCacheMap()
+  pruneCache(map)
+  const cache = map[url]
+  if (!cache) return null
+  return cache
+}
+
+const saveCacheEntry = async (cache: VideoInfoCacheEntry): Promise<void> => {
+  const map = await getCacheMap()
+  pruneCache(map)
+  map[cache.url] = cache
+  await browser.storage.local.set({ videoInfoCacheByUrl: map })
+}
+
+const fetchAndCache = async (url: string, tabId?: number): Promise<void> => {
+  if (pendingRequests.has(url)) {
+    return pendingRequests.get(url) as Promise<void>
+  }
+
+  const task = (async () => {
+    const existing = await loadCache(url)
+    if (existing?.status === 'ready') {
+      setActionIcon('success', tabId)
+      return
+    }
+
+    setActionIcon('loading', tabId)
+    await saveCacheEntry({ url, status: 'pending', fetchedAt: Date.now() })
+
+    try {
+      const info = await requestVideoInfo(url)
+      await saveCacheEntry({ url, status: 'ready', fetchedAt: Date.now(), info })
+      setActionIcon('success', tabId)
+    } catch (error) {
+      const message = error instanceof Error ? error.message : 'Failed to fetch video info.'
+      await saveCacheEntry({ url, status: 'error', fetchedAt: Date.now(), error: message })
+      setActionIcon('default', tabId)
+    }
+  })()
+
+  pendingRequests.set(url, task)
+  try {
+    await task
+  } finally {
+    pendingRequests.delete(url)
+  }
+}
+
+export default defineBackground(() => {
+  browser.runtime.onMessage.addListener((message: { type?: string; url?: string }, sender) => {
+    if (message.type !== 'video-info:fetch' || !message.url) {
+      return
+    }
+    void fetchAndCache(message.url, sender.tab?.id)
+  })
+})