const express = require('express')
const router = express.Router()
const async = require('async')
const path = require('path')
const multer = require('multer')
const fs = require('fs-extra')
const upload = multer({ dest: 'uploads' })

const sharp = require('sharp')

const TOL = require('../../tools/common')
const CFG = require('../../config')
var CTX = null

module.exports = function (pCtx) {
  CTX = pCtx
  router.post('/upload', upload.single('media'), handleUploadedMedia)

  router.get('/get/:id', function (req, res) {
    let mediaId = req.params.id
    CTX.restapi.media.__services.readOne(mediaId, {projection: {path: 1}}, function (pErr, pResult) {
      if (pErr) {
        return res.status(404).send('Media:Media:NotFound')
      }
      let mediaPath = path.join(CFG.media.documents, pResult.data.path)
      fs.access(mediaPath, fs.constants.F_OK, function (pErr) {
        if (pErr) {
          return res.status(404).send('Media:File:NotFound')
        }
        res.sendFile(mediaPath)
      })
    })
  })

  router.get('/preview/:id', function (req, res) {
    let mediaId = req.params.id
    CTX.restapi.media.__services.readOne(mediaId, {projection: {mimetype: 1, path: 1}}, function (pErr, pResult) {
      if (pErr) {
        return res.sendFile(CFG.media['404'])
      }

      let media = pResult.data
      let mimetypes = media.mimetype.split('/')
      let type = mimetypes[0]
      let subtype = mimetypes[1]

      switch (type) {
        case 'image':
          let mediaPath = path.join(CFG.media.documents, media.path)
          getPreviewFromImage(res, mediaPath, req.query)
          break
        default:
          res.sendFile(CFG.media['404'])
      }
    })
  })

  return router
}

function getPreviewFromImage (res, pPath, pQuery, pMedia) {
  let query = pQuery
  query.width = parseInt(query.width) || null
  query.height = parseInt(query.height) || null
  query.fit = query.fit || 'cover'
  if (!query.width && !query.height) {
    query.width = 1024
  }

  let outName = TOL.createHash(JSON.stringify(query), 'sha1')
  let outPath = path.join(CFG.media.cache, generatePathFromMediaId(outName))
  let outFull = path.join(outPath, `${outName}.jpg`)

  let tasks = []

  tasks.push(function (pCb) {
    fs.ensureDir(outPath, pErr => pCb(pErr))
  })

  tasks.push(function (pCb) {
    sharp(pPath)
      .resize(query.width, query.height, {fit: query.fit})
      .toFile(outFull, function (pErr) {
        pCb(pErr)
      })
  })

  async.waterfall(tasks, function (pErr) {
    if (pErr) {
      console.log(pErr)
      res.sendFile(CFG.media['404'])
    } else {
      res.sendFile(outFull)
    }
  })
}

function handleUploadedMedia (req, res) {
  let tasks = []
  let file = req.file
  let fileKey = {
    coll: '__default',
    id: '',
    path: ''
  }
  let ext = getExtensionFromMimetype(file.mimetype)
  let currentDate = new Date()

  if (req.body.docColl && req.body.docId && req.body.docPath) {
    fileKey = {
      coll: req.body.docColl,
      id: req.body.docId,
      path: req.body.docPath
    }
  }

  let mediaId = TOL.createHash(JSON.stringify(fileKey.coll === '__default' ? file : fileKey), 'sha1')
  let outPath = path.join(CFG.media.documents, generatePathFromMediaId(mediaId))
  let outName = `media.${ext}`
  let outFull = path.join(outPath, outName)
  let isAlreadyExisting = false

  file.createdAt = currentDate
  file.fileKey = fileKey

  tasks.push(function (pCb) {
    fs.ensureDir(outPath, pErr => pCb(pErr))
  })

  tasks.push(function (pCb) {
    fs.move(file.path, outFull, { overwrite: true }, pErr => pCb(pErr))
  })

  tasks.push(function (pCb) {
    fs.writeFile(path.join(outPath, 'info'), JSON.stringify(file, null, 2), 'utf8', pErr => pCb(pErr))
  })

  tasks.push(function (pCb) {
    CTX.restapi.media.__services.readOne(mediaId, {projection: {_id: 1}}, function (pErr, pResult) {
      if (pResult && pResult.ok) {
        isAlreadyExisting = true
      }
      pCb()
    })
  })

  tasks.push(function (pCb) {
    let doc = {
      _id: mediaId,
      name: outName,
      originalName: file.originalname,
      extension: ext,
      path: path.join(generatePathFromMediaId(mediaId), outName),
      fileKey: fileKey,
      mimetype: file.mimetype,
      size: file.size
    }

    if (isAlreadyExisting) {
      CTX.restapi.media.__services.update(mediaId, doc, req.user, 'media', function (pErr, pResult) {
        pCb(pErr)
      })
    } else {
      CTX.restapi.media.__services.create(doc, req.user, function (pErr, pResult) {
        pCb(pErr)
      })
    }
  })

  async.waterfall(tasks, function (pErr) {
    res.done(pErr, {
      ok: pErr ? 0 : 1,
      mediaId: mediaId
    })
  })
}

function generatePathFromMediaId (pMediaId) {
  let outSubf = pMediaId.slice(0, 4)
  return path.join(outSubf, pMediaId)
}

function getExtensionFromMimetype (pMimetype) {
  let ext = 'unknown'
  let mimetypes = pMimetype.split('/')
  let type = mimetypes[0]
  let subtype = mimetypes[1]
  switch (type) {
    case 'audio':
    case 'video':
    case 'image':
      ext = subtype
      break
    case 'application/pdf':
      ext = 'pdf'
      break
    default:
  }

  return ext
}