const Router = require('@koa/router')
const r = new Router()
module.exports = r

const koaBody = require('koa-body')
const {
  download: ytdl,
  getTitle
} = require('@libs/youtube.js')
const qs = require('querystring')
const fs = require('fs')
const path = require('path')
const config = require('@config/index.js')
const store = require('@libs/memstore.js')

r.post('/download', koaBody(), async c => {
  console.log(c.request)
  const { url } = c.request.body
  if (typeof url !== 'string' || url.trim().length === 0) c.throw(400, 'url is empty')
  let id = ''
  if (/:\/\/youtu\.be/i.test(url)) {
    const arr = url.split('/')
    id = arr[arr.length - 1]
  } else {
    const arr = url.split('?')
    if (arr.length !== 2) c.throw(400, 'url format error')
    const q = qs.parse(arr[1])
    if (!('v' in q) || typeof q.v !== 'string' || q.v.length === 0) c.throw(400, 'url format error')
    id = q.v
  }

  const title = await getTitle(url)

  const result = await ytdl(url)
  if (!result) c.throw(500, 'download fail')

  store.set(`${id}.mp3`, { title })

  c.body = {
    url: `${c.protocol}://${c.host.replace(/\/$/, '')}/api/youtube/download?file=${id}.mp3`
  }
  c.status = 200
})

r.get('/download', async c => {
  const { file } = c.query
  if (typeof file !== 'string' || file.trim().length === 0) c.throw(400, 'file is empty')

  const fp = path.resolve(config.download_location, file)
  if (!fs.existsSync(fp)) c.throw(404, 'file not found')

  const fileInfo = store.get(file)
  let fn = file
  if (fileInfo !== null && 'title' in fileInfo) fn = `${fileInfo.title}.mp3`

  const rs = fs.createReadStream(fp)
  c.set('Content-disposition', `attachment; filename="${encodeURIComponent(fn)}"; filename*="utf8''${encodeURIComponent(fn)}";`)
  c.set('Content-Type', 'audio/mpeg')
  c.body = rs
  c.status = 200
})