feat(api): add Vimeo video metadata extraction support

- Create unified video-meta.ts API handler for both YouTube and Vimeo
- Add Vimeo oEmbed API integration for server-side metadata extraction
- Implement URL pattern matching for YouTube and Vimeo video detection
- Support both URL and videoId parameters for backward compatibility
- Add proper TypeScript types for Vimeo oEmbed response
- Include caching mechanism for Vimeo metadata (7-day cache)
- Remove unused @vimeo/player package dependency

The new API endpoint supports:
- YouTube: /api/video-meta?url=https://youtube.com/watch?v=ID or ?videoId=ID
- Vimeo: /api/video-meta?url=https://vimeo.com/ID
- Returns consistent response format for both platforms

api/video-meta.ts

@@ -0,0 +1,197 @@
+import type { VercelRequest, VercelResponse } from '@vercel/node'
+import { getSubtitles, getVideoDetails } from '@treeee/youtube-caption-extractor'
+
+type Caption = { start: number; dur: number; text: string }
+
+type CacheEntry = {
+  body: unknown
+  expires: number
+}
+
+type VimeoOEmbedResponse = {
+  title: string
+  description: string
+  author_name: string
+  author_url: string
+  provider_name: string
+  provider_url: string
+  type: string
+  version: string
+  width: number
+  height: number
+  html: string
+  thumbnail_url: string
+  thumbnail_width: number
+  thumbnail_height: number
+}
+
+// In-memory cache for 7 days
+const WEEK_MS = 7 * 24 * 60 * 60 * 1000
+const memoryCache = new Map<string, CacheEntry>()
+
+function buildKey(videoId: string, lang: string, preferAuto?: string | string[], source?: string) {
+  return `${source || 'video'}|${videoId}|${lang}|${preferAuto ? 'auto' : 'manual'}`
+}
+
+function ok(res: VercelResponse, data: unknown) {
+  res.setHeader('Cache-Control', 'public, max-age=86400, s-maxage=604800') // client: 1d, CDN: 7d
+  return res.status(200).json(data)
+}
+
+function bad(res: VercelResponse, code: number, message: string) {
+  return res.status(code).json({ error: message })
+}
+
+function extractVideoId(url: string): { id: string; source: 'youtube' | 'vimeo' } | null {
+  // YouTube patterns
+  const youtubePatterns = [
+    /(?:youtube\.com\/watch\?v=|youtu\.be\/|youtube\.com\/embed\/)([^&\n?#]+)/,
+    /youtube\.com\/v\/([^&\n?#]+)/
+  ]
+  
+  for (const pattern of youtubePatterns) {
+    const match = url.match(pattern)
+    if (match) {
+      return { id: match[1], source: 'youtube' }
+    }
+  }
+  
+  // Vimeo patterns
+  const vimeoPatterns = [
+    /vimeo\.com\/(\d+)/,
+    /player\.vimeo\.com\/video\/(\d+)/
+  ]
+  
+  for (const pattern of vimeoPatterns) {
+    const match = url.match(pattern)
+    if (match) {
+      return { id: match[1], source: 'vimeo' }
+    }
+  }
+  
+  return null
+}
+
+async function pickCaptions(videoID: string, preferredLangs: string[], manualFirst: boolean): Promise<{ caps: Caption[]; lang: string; isAuto: boolean } | null> {
+  for (const lang of preferredLangs) {
+    try {
+      const caps = await getSubtitles({ videoID, lang, auto: !manualFirst ? true : false })
+      if (Array.isArray(caps) && caps.length > 0) {
+        return { caps, lang, isAuto: !manualFirst }
+      }
+    } catch {
+      // try next
+    }
+  }
+  return null
+}
+
+async function getVimeoMetadata(videoId: string): Promise<{ title: string; description: string }> {
+  const vimeoUrl = `https://vimeo.com/${videoId}`
+  const oembedUrl = `https://vimeo.com/api/oembed.json?url=${encodeURIComponent(vimeoUrl)}`
+  
+  const response = await fetch(oembedUrl)
+  if (!response.ok) {
+    throw new Error(`Vimeo oEmbed API returned ${response.status}`)
+  }
+  
+  const data: VimeoOEmbedResponse = await response.json()
+  
+  return {
+    title: data.title || '',
+    description: data.description || ''
+  }
+}
+
+export default async function handler(req: VercelRequest, res: VercelResponse) {
+  const url = (req.query.url as string | undefined)?.trim()
+  const videoId = (req.query.videoId as string | undefined)?.trim()
+  
+  if (!url && !videoId) {
+    return bad(res, 400, 'Missing url or videoId parameter')
+  }
+
+  // Extract video info from URL or use provided videoId
+  let videoInfo: { id: string; source: 'youtube' | 'vimeo' }
+  
+  if (url) {
+    const extracted = extractVideoId(url)
+    if (!extracted) {
+      return bad(res, 400, 'Unsupported video URL. Only YouTube and Vimeo are supported.')
+    }
+    videoInfo = extracted
+  } else {
+    // If only videoId is provided, assume YouTube for backward compatibility
+    videoInfo = { id: videoId!, source: 'youtube' }
+  }
+
+  const lang = ((req.query.lang as string | undefined) || 'en').toLowerCase()
+  const uiLocale = (req.headers['x-ui-locale'] as string | undefined)?.toLowerCase()
+  const preferAuto = req.query.preferAuto === 'true'
+
+  const cacheKey = buildKey(videoInfo.id, lang, preferAuto ? 'auto' : undefined, videoInfo.source)
+  const now = Date.now()
+  const cached = memoryCache.get(cacheKey)
+  if (cached && cached.expires > now) {
+    return ok(res, cached.body)
+  }
+
+  try {
+    if (videoInfo.source === 'youtube') {
+      // YouTube handling
+      const details: unknown = await getVideoDetails({ videoID: videoInfo.id, lang })
+      // Be tolerant to possible shapes returned by the extractor
+      const title = (details as { title?: string } | undefined)?.title || ''
+      const d1 = (details as { description?: string } | undefined)?.description
+      const d2 = (details as { shortDescription?: string } | undefined)?.shortDescription
+      const d3 = (details as { descriptionText?: string } | undefined)?.descriptionText
+      const description = d1 || d2 || d3 || ''
+
+      // Language order: manual en -> uiLocale -> lang -> any manual, then auto with same order
+      const langs: string[] = Array.from(new Set(['en', uiLocale, lang].filter(Boolean) as string[]))
+
+      let selected = null as null | { caps: Caption[]; lang: string; isAuto: boolean }
+      // Manual first
+      selected = await pickCaptions(videoInfo.id, langs, true)
+      if (!selected) {
+        // Try auto
+        selected = await pickCaptions(videoInfo.id, langs, false)
+      }
+
+      const captions = selected?.caps || []
+      const transcript = captions.map(c => c.text).join(' ').trim()
+      const response = {
+        title,
+        description,
+        captions,
+        transcript,
+        lang: selected?.lang || lang,
+        isAuto: selected?.isAuto || false,
+        source: 'youtube'
+      }
+
+      memoryCache.set(cacheKey, { body: response, expires: now + WEEK_MS })
+      return ok(res, response)
+    } else if (videoInfo.source === 'vimeo') {
+      // Vimeo handling
+      const { title, description } = await getVimeoMetadata(videoInfo.id)
+      
+      const response = {
+        title,
+        description,
+        captions: [], // Vimeo doesn't provide captions through oEmbed API
+        transcript: '', // No transcript available
+        lang: 'en', // Default language
+        isAuto: false, // Not applicable for Vimeo
+        source: 'vimeo'
+      }
+
+      memoryCache.set(cacheKey, { body: response, expires: now + WEEK_MS })
+      return ok(res, response)
+    } else {
+      return bad(res, 400, 'Unsupported video source')
+    }
+  } catch (e) {
+    return bad(res, 500, `Failed to fetch ${videoInfo.source} metadata`)
+  }
+}

api/vimeo-meta.ts

@@ -0,0 +1,93 @@
+import type { VercelRequest, VercelResponse } from '@vercel/node'
+
+type CacheEntry = {
+  body: unknown
+  expires: number
+}
+
+type VimeoOEmbedResponse = {
+  title: string
+  description: string
+  author_name: string
+  author_url: string
+  provider_name: string
+  provider_url: string
+  type: string
+  version: string
+  width: number
+  height: number
+  html: string
+  thumbnail_url: string
+  thumbnail_width: number
+  thumbnail_height: number
+}
+
+// In-memory cache for 7 days
+const WEEK_MS = 7 * 24 * 60 * 60 * 1000
+const memoryCache = new Map<string, CacheEntry>()
+
+function buildKey(videoId: string) {
+  return `vimeo|${videoId}`
+}
+
+function ok(res: VercelResponse, data: unknown) {
+  res.setHeader('Cache-Control', 'public, max-age=86400, s-maxage=604800') // client: 1d, CDN: 7d
+  return res.status(200).json(data)
+}
+
+function bad(res: VercelResponse, code: number, message: string) {
+  return res.status(code).json({ error: message })
+}
+
+async function getVimeoMetadata(videoId: string): Promise<{ title: string; description: string }> {
+  const vimeoUrl = `https://vimeo.com/${videoId}`
+  const oembedUrl = `https://vimeo.com/api/oembed.json?url=${encodeURIComponent(vimeoUrl)}`
+  
+  const response = await fetch(oembedUrl)
+  if (!response.ok) {
+    throw new Error(`Vimeo oEmbed API returned ${response.status}`)
+  }
+  
+  const data: VimeoOEmbedResponse = await response.json()
+  
+  return {
+    title: data.title || '',
+    description: data.description || ''
+  }
+}
+
+export default async function handler(req: VercelRequest, res: VercelResponse) {
+  const videoId = (req.query.videoId as string | undefined)?.trim()
+  if (!videoId) return bad(res, 400, 'Missing videoId')
+
+  // Validate that videoId is a number
+  if (!/^\d+$/.test(videoId)) {
+    return bad(res, 400, 'Invalid Vimeo video ID - must be numeric')
+  }
+
+  const cacheKey = buildKey(videoId)
+  const now = Date.now()
+  const cached = memoryCache.get(cacheKey)
+  if (cached && cached.expires > now) {
+    return ok(res, cached.body)
+  }
+
+  try {
+    const { title, description } = await getVimeoMetadata(videoId)
+    
+    const response = {
+      title,
+      description,
+      captions: [], // Vimeo doesn't provide captions through oEmbed API
+      transcript: '', // No transcript available
+      lang: 'en', // Default language
+      isAuto: false, // Not applicable for Vimeo
+      source: 'vimeo'
+    }
+
+    memoryCache.set(cacheKey, { body: response, expires: now + WEEK_MS })
+    return ok(res, response)
+  } catch (e) {
+    return bad(res, 500, 'Failed to fetch Vimeo metadata')
+  }
+}