/**
 * Shared utilities for converting external service URLs to embeddable formats.
 * Used by lib's embed components and the hub's admin document editor.
 */

export function toGoogleSheetsEmbedUrl(url: string): string {
  if (url.includes('/htmlembed')) return url

  const match = url.match(/\/spreadsheets\/d\/([a-zA-Z0-9-_]+)/)
  if (!match) return url

  const gidMatch = url.match(/[#?&]gid=(\d+)/)
  const gid = gidMatch ? gidMatch[1] : '0'

  return `https://docs.google.com/spreadsheets/d/${match[1]}/htmlembed?widget=true&chrome=false&headers=false&gid=${gid}`
}

export function toGoogleSheetsOriginalUrl(url: string): string {
  const match = url.match(/\/spreadsheets\/d\/([a-zA-Z0-9-_]+)/)
  if (!match) return url

  const gidMatch = url.match(/[#?&]gid=(\d+)/)
  const gid = gidMatch ? gidMatch[1] : '0'

  return `https://docs.google.com/spreadsheets/d/${match[1]}/edit#gid=${gid}`
}

/**
 * Convert a Figma URL to an embeddable URL.
 * Slides/deck URLs map to `deck` (present) by default; `slidesView: 'browse'` switches to `slides` (browse).
 */
export function toFigmaEmbedUrl(
  url: string,
  opts?: { slidesView?: 'present' | 'browse' }
): string {
  if (url.includes('embed.figma.com')) return url
  if (url.includes('figma.com/embed')) return url

  const match = url.match(
    /figma\.com\/(design|file|proto|board|slides|deck)\/([a-zA-Z0-9]+)(?:\/([^?]*))?(\?.*)?$/
  )

  if (match) {
    const [, urlType, fileKey, titleSlug, queryString] = match
    const isSlides = urlType === 'slides' || urlType === 'deck'
    const embedType =
      urlType === 'proto' ? 'proto'
      : isSlides ? (opts?.slidesView === 'browse' ? 'slides' : 'deck')
      : 'design'
    const pathSuffix = titleSlug ? `/${titleSlug}` : ''

    const params = new URLSearchParams(queryString?.replace(/^\?/, '') || '')
    if (!params.has('embed-host')) {
      params.set('embed-host', 'flamingo')
    }
    const clientId = process.env.NEXT_PUBLIC_FIGMA_CLIENT_ID
    if (clientId && !params.has('client-id')) {
      params.set('client-id', clientId)
    }

    return `https://embed.figma.com/${embedType}/${fileKey}${pathSuffix}?${params.toString()}`
  }

  return `https://www.figma.com/embed?embed-host=flamingo&url=${encodeURIComponent(url)}`
}

export function isFigmaSlidesUrl(url: string): boolean {
  if (!url) return false
  return /(?:www\.|embed\.)?figma\.com\/(?:slides|deck)\/[a-zA-Z0-9]+/.test(url)
}

export function toFigmaOriginalUrl(url: string): string {
  if (url.includes('embed.figma.com')) {
    return url.replace('embed.figma.com', 'www.figma.com').replace(/\?.*$/, '')
  }
  return url.replace(/\?.*$/, '')
}

/**
 * The self-hosted MIRROR url for a claude artifact url — the whole
 * mirror mechanism is UNDER THE HOOD: the viewer detects a claude url,
 * DERIVES the mirror location from the artifact's own id under the
 * host's configured storage-view proxy base, and frames the downloaded
 * copy from there. No per-link data, no props, no shortcode changes —
 * 100% transparent to every consumer.
 *
 * `storageViewBaseUrl` comes from `EndpointsRuntime` — the SAME
 * host-overridable proxy-path mechanism every other lib→API call uses
 * (a reverse-proxied embedder remaps it; a host without the proxy omits
 * it and gets `null` here, i.e. no mirror leg at all).
 *
 * `null` when the base is absent or the url carries no artifact id. The
 * derived url is the configured base + a validated uuid — safe as a
 * frame source without further checks. KEEP THE OBJECT NAMING IN SYNC
 * with the hub's `lib/data/design-brief-mirror.cjs` (bucket +
 * `<uuid>.html`) — that module owns the ingest/audit half.
 */
export function toClaudeMirrorPath(
  url: string | null | undefined,
  storageViewBaseUrl: string | null | undefined,
): string | null {
  if (!url || !storageViewBaseUrl) return null
  try {
    const u = new URL(url)
    const host = u.hostname.toLowerCase()
    const id =
      (host === 'claude.ai' &&
        /^\/(?:code\/artifact|public\/artifacts)\/([0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})(?:[/?#]|$)/i.exec(
          u.pathname,
        )?.[1]) ||
      (host === 'claude.site' &&
        /^\/artifacts\/([0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})(?:[/?#]|$)/i.exec(
          u.pathname,
        )?.[1]) ||
      null
    return id
      ? `${storageViewBaseUrl.replace(/\/$/, '')}/design-briefs/${id.toLowerCase()}.html`
      : null
  } catch {
    return null
  }
}

/**
 * The EMBED url for a published Claude artifact, or `null` when the link is not
 * one we can frame — the Claude counterpart of `toFigmaEmbedUrl`.
 *
 * claude.ai serves `frame-ancestors 'self'` on the artifact page itself, but a
 * PUBLISHED artifact also has an `/embed` route whose `frame-ancestors` carries
 * the domains its author allow-listed under "Get embed code → Allowed domains".
 * That is Anthropic's supported way to put an artifact on another site, so that
 * is what the iframe points at.
 *
 * Returns `null` for everything else, including a Claude CODE url
 * (`claude.ai/code/artifact/…`), whose Share dialog exposes no Embed settings
 * and whose `/embed` path answers `frame-ancestors 'self'` (verified against
 * real artifacts, 2026-08). A trailing `/embed` is accepted because that is the
 * url "Get embed code" hands the author.
 */
export function toClaudeEmbedUrl(url: string | null | undefined): string | null {
  if (!url) return null
  try {
    const u = new URL(url)
    const host = u.hostname.toLowerCase()
    // `claude.site/artifacts/<id>` 308-redirects to the claude.ai public url.
    const publicId =
      (host === 'claude.ai' && /^\/public\/artifacts\/([\w-]+)(?:\/embed)?\/?$/.exec(u.pathname)?.[1]) ||
      (host === 'claude.site' && /^\/artifacts\/([\w-]+)(?:\/embed)?\/?$/.exec(u.pathname)?.[1]) ||
      null
    return publicId ? `https://claude.ai/public/artifacts/${publicId}/embed` : null
  } catch {
    return null
  }
}