'use strict'

const config = require('config')
const express = require('express')
const fs = require('fs')
const path = require('path')
const multer = require('multer')

const constants = require('../../../initializers/constants')
const logger = require('../../../helpers/logger')
const friends = require('../../../lib/friends')
const middleware = require('../../../middlewares')
const oAuth2 = require('../../../middlewares/oauth2')
const reqValidator = middleware.reqValidators.videos
const utils = require('../../../helpers/utils')
const Videos = require('../../../models/videos') // model
const videos = require('../../../lib/videos')
const webtorrent = require('../../../lib/webtorrent')

const router = express.Router()
const uploads = config.get('storage.uploads')

// multer configuration
const storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, uploads)
  },

  filename: function (req, file, cb) {
    let extension = ''
    if (file.mimetype === 'video/webm') extension = 'webm'
    else if (file.mimetype === 'video/mp4') extension = 'mp4'
    else if (file.mimetype === 'video/ogg') extension = 'ogv'
    utils.generateRandomString(16, function (err, randomString) {
      const fieldname = err ? undefined : randomString
      cb(null, fieldname + '.' + extension)
    })
  }
})

const reqFiles = multer({ storage: storage }).fields([{ name: 'videofile', maxCount: 1 }])
const thumbnailsDir = path.join(__dirname, '..', '..', '..', '..', config.get('storage.thumbnails'))

router.get('/', listVideos)
router.post('/', oAuth2.authenticate, reqFiles, reqValidator.videosAdd, addVideo)
router.get('/:id', reqValidator.videosGet, getVideos)
router.delete('/:id', oAuth2.authenticate, reqValidator.videosRemove, removeVideo)
router.get('/search/:name', reqValidator.videosSearch, searchVideos)

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

module.exports = router

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

function addVideo (req, res, next) {
  const videoFile = req.files.videofile[0]
  const videoInfos = req.body

  videos.seed(videoFile.path, function (err, torrent) {
    if (err) {
      logger.error('Cannot seed this video.')
      return next(err)
    }

    videos.getVideoDuration(videoFile.path, function (err, duration) {
      if (err) {
        // TODO: unseed the video
        logger.error('Cannot retrieve metadata of the file.')
        return next(err)
      }

      videos.getVideoThumbnail(videoFile.path, function (err, thumbnailName) {
        if (err) {
          // TODO: unseed the video
          logger.error('Cannot make a thumbnail of the video file.')
          return next(err)
        }

        const videoData = {
          name: videoInfos.name,
          namePath: videoFile.filename,
          description: videoInfos.description,
          magnetUri: torrent.magnetURI,
          author: res.locals.oauth.token.user.username,
          duration: duration,
          thumbnail: thumbnailName
        }

        Videos.add(videoData, function (err) {
          if (err) {
            // TODO unseed the video
            logger.error('Cannot insert this video in the database.')
            return next(err)
          }

          fs.readFile(thumbnailsDir + thumbnailName, function (err, data) {
            if (err) {
              // TODO: remove video?
              logger.error('Cannot read the thumbnail of the video')
              return next(err)
            }

            // Set the image in base64
            videoData.thumbnailBase64 = new Buffer(data).toString('base64')
            // Now we'll add the video's meta data to our friends
            friends.addVideoToFriends(videoData)

            // TODO : include Location of the new video -> 201
            res.type('json').status(204).end()
          })
        })
      })
    })
  })
}

function getVideos (req, res, next) {
  Videos.get(req.params.id, function (err, videoObj) {
    if (err) return next(err)

    const state = videos.getVideoState(videoObj)
    if (state.exist === false) {
      return res.type('json').status(204).end()
    }

    res.json(getFormatedVideo(videoObj))
  })
}

function listVideos (req, res, next) {
  Videos.list(function (err, videosList) {
    if (err) return next(err)

    res.json(getFormatedVideos(videosList))
  })
}

function removeVideo (req, res, next) {
  const videoId = req.params.id
  Videos.get(videoId, function (err, video) {
    if (err) return next(err)

    removeTorrent(video.magnetUri, function () {
      Videos.removeOwned(req.params.id, function (err) {
        if (err) return next(err)

        videos.removeVideosDataFromDisk([ video ], function (err) {
          if (err) logger.error('Cannot remove video data from disk.', { video: video })

          const params = {
            name: video.name,
            magnetUri: video.magnetUri
          }

          friends.removeVideoToFriends(params)
          res.type('json').status(204).end()
        })
      })
    })
  })
}

function searchVideos (req, res, next) {
  Videos.search(req.params.name, function (err, videosList) {
    if (err) return next(err)

    res.json(getFormatedVideos(videosList))
  })
}

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

function getFormatedVideo (videoObj) {
  const formatedVideo = {
    id: videoObj._id,
    name: videoObj.name,
    description: videoObj.description,
    podUrl: videoObj.podUrl,
    isLocal: videos.getVideoState(videoObj).owned,
    magnetUri: videoObj.magnetUri,
    author: videoObj.author,
    duration: videoObj.duration,
    thumbnailPath: constants.THUMBNAILS_STATIC_PATH + '/' + videoObj.thumbnail
  }

  return formatedVideo
}

function getFormatedVideos (videosObj) {
  const formatedVideos = []

  videosObj.forEach(function (videoObj) {
    formatedVideos.push(getFormatedVideo(videoObj))
  })

  return formatedVideos
}

// Maybe the torrent is not seeded, but we catch the error to don't stop the removing process
function removeTorrent (magnetUri, callback) {
  try {
    webtorrent.remove(magnetUri, callback)
  } catch (err) {
    logger.warn('Cannot remove the torrent from WebTorrent', { err: err })
    return callback(null)
  }
}