import express from 'express'
import { escapeHTML, forceNumber } from '@peertube/peertube-core-utils'
import { MChannelSummary } from '@server/types/models/index.js'
import { EMBED_SIZE, PREVIEWS_SIZE, THUMBNAILS_SIZE, WEBSERVER } from '../initializers/constants.js'
import { apiRateLimiter, asyncMiddleware, oembedValidator } from '../middlewares/index.js'
import { accountNameWithHostGetValidator } from '../middlewares/validators/index.js'

const servicesRouter = express.Router()

servicesRouter.use('/oembed',
  apiRateLimiter,
  asyncMiddleware(oembedValidator),
  generateOEmbed
)
servicesRouter.use('/redirect/accounts/:accountName',
  apiRateLimiter,
  asyncMiddleware(accountNameWithHostGetValidator),
  redirectToAccountUrl
)

// ---------------------------------------------------------------------------

export {
  servicesRouter
}

// ---------------------------------------------------------------------------

function generateOEmbed (req: express.Request, res: express.Response) {
  if (res.locals.videoAll) return generateVideoOEmbed(req, res)

  return generatePlaylistOEmbed(req, res)
}

function generatePlaylistOEmbed (req: express.Request, res: express.Response) {
  const playlist = res.locals.videoPlaylistSummary

  const json = buildOEmbed({
    channel: playlist.VideoChannel,
    title: playlist.name,
    embedPath: playlist.getEmbedStaticPath() + buildPlayerURLQuery(req.query.url),
    previewPath: playlist.getThumbnailStaticPath(),
    previewSize: THUMBNAILS_SIZE,
    req
  })

  return res.json(json)
}

function generateVideoOEmbed (req: express.Request, res: express.Response) {
  const video = res.locals.videoAll

  const json = buildOEmbed({
    channel: video.VideoChannel,
    title: video.name,
    embedPath: video.getEmbedStaticPath() + buildPlayerURLQuery(req.query.url),
    previewPath: video.getPreviewStaticPath(),
    previewSize: PREVIEWS_SIZE,
    req
  })

  return res.json(json)
}

function buildPlayerURLQuery (inputQueryUrl: string) {
  const allowedParameters = new Set([
    'start',
    'stop',
    'loop',
    'autoplay',
    'muted',
    'controls',
    'controlBar',
    'title',
    'api',
    'warningTitle',
    'peertubeLink',
    'p2p',
    'subtitle',
    'bigPlayBackgroundColor',
    'mode',
    'foregroundColor'
  ])

  const params = new URLSearchParams()

  new URL(inputQueryUrl).searchParams.forEach((v, k) => {
    if (allowedParameters.has(k)) {
      params.append(k, v)
    }
  })

  const stringQuery = params.toString()
  if (!stringQuery) return ''

  return '?' + stringQuery
}

function buildOEmbed (options: {
  req: express.Request
  title: string
  channel: MChannelSummary
  previewPath: string | null
  embedPath: string
  previewSize: {
    height: number
    width: number
  }
}) {
  const { req, previewSize, previewPath, title, channel, embedPath } = options

  const webserverUrl = WEBSERVER.URL
  const maxHeight = forceNumber(req.query.maxheight)
  const maxWidth = forceNumber(req.query.maxwidth)

  const embedUrl = webserverUrl + embedPath
  const embedTitle = escapeHTML(title)

  let thumbnailUrl = previewPath
    ? webserverUrl + previewPath
    : undefined

  let embedWidth = EMBED_SIZE.width
  if (maxWidth < embedWidth) embedWidth = maxWidth

  let embedHeight = EMBED_SIZE.height
  if (maxHeight < embedHeight) embedHeight = maxHeight

  // Our thumbnail is too big for the consumer
  if (
    (maxHeight !== undefined && maxHeight < previewSize.height) ||
    (maxWidth !== undefined && maxWidth < previewSize.width)
  ) {
    thumbnailUrl = undefined
  }

  const html = `<iframe width="${embedWidth}" height="${embedHeight}" sandbox="allow-same-origin allow-scripts allow-popups" ` +
    `title="${embedTitle}" src="${embedUrl}" frameborder="0" allowfullscreen></iframe>`

  const json: any = {
    type: 'video',
    version: '1.0',
    html,
    width: embedWidth,
    height: embedHeight,
    title,
    author_name: channel.name,
    author_url: channel.Actor.url,
    provider_name: 'PeerTube',
    provider_url: webserverUrl
  }

  if (thumbnailUrl !== undefined) {
    json.thumbnail_url = thumbnailUrl
    json.thumbnail_width = previewSize.width
    json.thumbnail_height = previewSize.height
  }

  return json
}

function redirectToAccountUrl (req: express.Request, res: express.Response, next: express.NextFunction) {
  return res.redirect(res.locals.account.Actor.url)
}