import path from 'path'
import express from 'express'
import session from 'express-session'
import bodyParser from 'body-parser'
import connectSession from 'connect-redis'
import redis from 'redis'
import http from 'http'
import ffmpeg from 'fluent-ffmpeg'
import { user, userMiddleware } from './user'
import { dbPromise } from './database'

import * as asn from './common/async'

import * as playlist from './playlist'
import * as lastfm from './lastfm'
import * as external from './external.js'

require('express-async-errors')

const values = require(path.join(process.cwd(), 'values.json'))
const tracksPerPage = 100

const app = express()
const port = process.env.PORT || 3000

const dev = process.env.NODE_ENV === 'development'
const server = http.createServer(app)

if (dev) {
  const morgan = require('morgan')
  app.use(morgan('dev'))
}

app.set('trust proxy', 1)
app.use(bodyParser.urlencoded({ extended: false }))
app.use(bodyParser.json())

const router = express.Router()

const sortfields = ['id', 'track', 'artist', 'title', 'album', 'year']
const srchcategories = ['title', 'artist', 'album']

const SessionStore = connectSession(session)
app.use(session({
  key: values.session_key || 'Session',
  secret: values.session_secret || 'ch4ng3 m3!',
  store: new SessionStore({ client: redis.createClient(values.redis || { port: 6379 }) }),
  resave: false,
  saveUninitialized: true,
  cookie: {
    secure: !dev,
    maxAge: 2678400000 // 1 month
  }
}))

// ------ //
// TRACKS //
// ------ //

router.get('/tracks', userMiddleware, async (req, res) => {
  let page = parseInt(req.query.page) || 1
  if (isNaN(page)) {
    page = 1
  }

  let sort = req.query.sort
  if (!sort || sortfields.indexOf(sort.toLowerCase()) === -1) {
    sort = 'artist'
  }

  let sortdir = req.query.sortdir
  if (!sortdir || (sortdir !== 'desc' && sortdir !== 'asc')) {
    sortdir = 'asc'
  }

  const db = await dbPromise
  const count = (await db.get('SELECT COUNT(*) as \'count\' FROM Track')).count

  const pageCount = Math.ceil(count / tracksPerPage)

  if (page > pageCount) page = pageCount

  const offset = (page - 1) * tracksPerPage
  const tracks = await db.all(`SELECT * FROM Track ORDER BY ${sort} ${sortdir} LIMIT ? OFFSET ?`, tracksPerPage, offset)

  for (const i in tracks) {
    delete tracks[i].file
  }

  res.jsonp({
    page, count, pageCount, tracks
  })
})

router.get('/tracks/search', userMiddleware, async (req, res) => {
  const streamable = (req.query.streamable === '1')
  let query = req.query.q
  let qr = ''
  let exact = false

  if (query.indexOf('http') !== -1) {
    const result = await external.searchURL(query)
    res.jsonp({
      page: 1, count: 1, pageCount: 1, tracks: result
    })
    return
  }

  if (query.indexOf(':') !== -1) {
    const ctr = query.split(':')

    if (srchcategories.indexOf(ctr[0]) !== -1) {
      qr = `ifnull(${ctr[0]}, '')`
      query = query.substring(ctr[0].length + 1)
    }
  }

  if (qr === '') {
    for (const c in srchcategories) {
      const cat = srchcategories[c]
      if (parseInt(c) !== 0) qr += ' || '
      qr += `ifnull(${cat}, '')`
    }
  }

  if (query.indexOf('=') !== -1 && query.indexOf('\\=') === -1) {
    query = query.replace('=', '')
    exact = true
  }

  const original = String(query)
  if (!exact) query = `%${query}%`

  let sort = req.query.sort
  if (!sort || sortfields.indexOf(sort.toLowerCase()) === -1) {
    sort = 'artist'
  }

  let sortdir = req.query.sortdir
  if (!sortdir || (sortdir !== 'desc' && sortdir !== 'asc')) {
    sortdir = 'asc'
  }

  // Paging
  let page = parseInt(req.query.page) || 1
  if (isNaN(page)) {
    page = 1
  }

  const db = await dbPromise
  let count = (await db.get(`SELECT COUNT(*) as 'count' FROM Track WHERE ${qr} LIKE ?`, query)).count
  let pageCount = Math.ceil(count / tracksPerPage)

  if (page > pageCount) page = pageCount

  const offset = (page - 1) * tracksPerPage
  let tracks = await db.all(`SELECT * FROM Track WHERE ${qr} LIKE ? ORDER BY ${sort} ${sortdir} LIMIT ? OFFSET ?`,
    query, tracksPerPage, offset)

  let llimit = tracksPerPage - count
  if (streamable && page === pageCount && llimit > 1) {
    if (llimit < 10) llimit = 10
    try {
      const lfm = await lastfm.search(original, llimit)
      if (lfm && lfm.length) {
        tracks = tracks.concat(lfm)
        count = count + lfm.length
        if (page === 0) page = 1
        if (pageCount === 0) pageCount = 1
      }
    } catch (e) {}
  }

  for (const i in tracks) {
    delete tracks[i].file
  }

  res.jsonp({
    page, count, pageCount, tracks
  })
})

router.get('/track/:id', userMiddleware, async (req, res, next) => {
  const id = req.params.id

  const db = await dbPromise
  let track = await db.get('SELECT * FROM Track WHERE id = ?', id)
  if (!track) {
    track = await external.getTrackMetaReal(id)
    if (!track) throw new Error('404 track not found')
  }

  delete track.file

  res.jsonp(track)
})

router.post('/track/:id', userMiddleware, async (req, res, next) => {
  const id = req.params.id
  const meta = req.body

  const db = await dbPromise
  const track = await db.get('SELECT file FROM Track WHERE id = ?', id)
  if (!track) throw new Error('404 track not found')

  const m = await asn.setMetadata(track.file, meta)
  await asn.updateDB(db, id, m.dbq)

  res.jsonp(m)
})

// --------- //
// PLAYLISTS //
// --------- //

// General playlist endpoints

router.post('/playlist/new', userMiddleware, async (req, res, next) => {
  if (!req.body.title) throw new Error('Title missing from body.')
  const id = await playlist.createPlaylist(req.session.user, req.body.title)
  res.jsonp({ success: true, playlist: id.id })
})

router.post('/playlist/delete/:playlistId', userMiddleware, async (req, res, next) => {
  const pId = req.params.playlistId
  await playlist.deletePlaylist(req.session.user, pId)
  res.jsonp({ success: true })
})

// Playlist track endpoints

router.post('/playlist/track/put/:playlistId/:trackId', userMiddleware, async (req, res, next) => {
  const pId = req.params.playlistId
  const tId = req.params.trackId
  await playlist.addTrack(req.session.user, pId, tId)
  res.jsonp({ success: true })
})

router.post('/playlist/track/remove/:playlistId/:trackId', userMiddleware, async (req, res, next) => {
  const pId = req.params.playlistId
  const tId = req.params.trackId
  await playlist.removeTrack(req.session.user, pId, tId)
  res.jsonp({ success: true })
})

router.post('/playlist/track/move/:playlistId/:trackId', userMiddleware, async (req, res, next) => {
  const pId = req.params.playlistId
  const tId = req.params.trackId
  const pos = parseInt(req.body.position)
  if (!pos || isNaN(pos)) throw new Error('Invalid position.')
  await playlist.moveTrack(req.session.user, pId, tId, pos)
  res.jsonp({ success: true })
})

router.get('/playlist', userMiddleware, async (req, res, next) => {
  res.jsonp(await playlist.getPlaylists(req.session.user))
})

router.get('/playlist/:id', userMiddleware, async (req, res, next) => {
  let sort = req.query.sort
  if (!sort || sortfields.indexOf(sort.toLowerCase()) === -1) {
    sort = 'artist'
  }

  let sortdir = req.query.sortdir
  if (!sortdir || (sortdir !== 'desc' && sortdir !== 'asc')) {
    sortdir = 'asc'
  }

  if (sort === 'id') {
    sort = 'ntry.indx'
  } else {
    sort = 'trck.' + sort
  }

  res.jsonp(await playlist.getPlaylist(req.params.id, sort, sortdir))
})

// -------------- //
// LASTFM CONNECT //
// -------------- //

async function scrobble (user, track) {
  if (await lastfm.getSessionForUser(user)) {
    try {
      await lastfm.scrobbleTrack(user, track)
    } catch (e) {
      console.warn('Track scrobbling failed for', user)
      console.error(e.stack)
    }
  }
}

router.get('/lastfm', userMiddleware, async (req, res, next) => {
  const sess = await lastfm.getSessionForUser(req.session.user)
  if (sess) return res.jsonp({ connected: true, name: sess.name })
  res.jsonp({ connected: false })
})

router.get('/lastfm/connect', userMiddleware, async (req, res, next) => {
  if (await lastfm.getSessionForUser(req.session.user)) throw new Error('You already have a LFM session!')
  res.redirect(lastfm.getAuthURL())
})

router.get('/lastfm/disconnect', userMiddleware, async (req, res, next) => {
  await lastfm.disregardSession(req.session.user)
  res.redirect('/')
})

router.get('/lastfm/_redirect', userMiddleware, async (req, res, next) => {
  const token = req.query.token
  if (!token) throw new Error('Failed to get token from LastFM!')
  const session = await lastfm.getSession(token)
  await lastfm.storeSession(req.session.user, session)
  res.redirect('/?success=lastfm')
})

router.post('/lastfm/scrobble/:track', userMiddleware, async (req, res, next) => {
  const id = req.params.track
  const user = req.session.user
  const db = await dbPromise
  let track = await db.get('SELECT title,artist,album,duration FROM Track WHERE id = ?', id)
  if (!track) {
    track = await external.getTrackMetaReal(id)
    if (!track) throw new Error('404 file not found')
  }
  await scrobble(user, track)
  res.jsonp({ success: true })
})

// ------------ //
// TRACK SERVER //
// ------------ //

router.get('/serve/by-id/:id', userMiddleware, async (req, res, next) => {
  const id = req.params.id
  const dl = (req.query.dl === '1')
  const db = await dbPromise
  let track = await db.get('SELECT file FROM Track WHERE id = ?', id)
  if (!track) {
    track = await external.getTrackMetaReal(id)
    if (!track) throw new Error('404 file not found')
    if (dl) {
      external.invokeDownload(id)
      return res.end('<p>OK</p><script>window.close();</script>')
    }
    dev && console.log('Remote', track.file)
    return ffmpeg(track.file)
      .audioCodec('libmp3lame')
      .format('mp3')
      .on('error', (e) => console.error(e))
      .pipe(res, { end: true })
  }

  const fpath = path.resolve(track.file)

  res.set('Cache-Control', 'public, max-age=31557600')
  if (dl) return res.download(fpath)

  res.redirect('/file/track' + fpath.substring(values.directory.length))
})

// ---------- //
// ERROR SINK //
// ---------- //

router.use((err, req, res, next) => {
  const msg = err.message
  dev && console.error(err.stack)
  res.status(msg.indexOf('404') !== -1 ? 404 : 400).jsonp({ error: err.message, stack: dev ? err.stack.toString() : undefined })
})

app.use('/user', user(values.oauth, values.registrations === true))

app.use('/api', router)
app.use('/file/track', express.static(path.resolve(values.directory)))
app.use('/', express.static(path.join(process.cwd(), 'public')))

const host = process.env.NODE_ENV === 'development' ? '0.0.0.0' : '127.0.0.1'

server.listen(port, host, async function () {
  const db = await dbPromise
  await db.migrate()
  console.log(`app running on port ${port}`)
})