import { IResolvers } from 'apollo-server-express'
import fs from 'fs'
import randombytes from 'randombytes'
import { uploadDir } from './constants'
import { checkPermission } from '../user/resolvers'
import { saveStreamToFile, processImage, processVideo, processAudio } from './utils'

export const resolvers: IResolvers = {
  Query: {
    fsFiles: async (parent, { directory }, context, info) => {
      checkPermission(context, 'ADMIN')
      const data = await fsFiles(directory)
      return data
    },
    files: (parent, args, context, info) => {
      checkPermission(context, 'ADMIN')
      return context.db.query.files(args, info)
    },
    file: (parent, args, context, info) => {
      checkPermission(context, 'ADMIN')
      return context.db.query.file(args, info)
    },
  },
  Mutation: {
    uploadFile: async (parent, { file, ...args }, context, info) => {
      checkPermission(context, 'ADMIN')
      const fileInfo = await uploadFile(file)

      return context.db.mutation.createFile(
        {
          data: {
            ...args,
            ...fileInfo,
            user: { connect: { id: context.req.userId } },
          },
        },
        info
      )
    },
    updateFile: (parent, args, context, info) => {
      checkPermission(context, 'ADMIN')
      return context.db.mutation.updateFile(args, info)
    },
    deleteFile: async (parent, { id }, context, info) => {
      checkPermission(context, 'ADMIN')
      const file = await context.db.query.file({ where: { id } })
      if (!file) throw Error(`File '${id}' not found.`)
      console.log(file)
      try {
        await fs.promises.unlink(file.path)
      } catch (error) {}
      return context.db.mutation.deleteFile({ where: { id } })
    },
  },
}

async function fsFiles(directory: string) {
  const fileList = await fs.promises.readdir(directory)
  return Promise.all(
    fileList.map(async (filename) => {
      const path = `${directory}/${filename}`
      const { size, ctime, mtime } = await fs.promises.stat(path)
      return {
        filename,
        path,
        size,
        ctime,
        mtime,
      }
    })
  )
}

async function uploadFile(file: any) {
  const { createReadStream, filename, mimetype, encoding } = await file
  const stream = createReadStream()
  const fsFilename = randombytes(16).toString('hex')
  const path: [string, string] = [uploadDir, fsFilename]
  const filePath = path.join('/')

  let fileDetails = { filename, mimetype, encoding, path: filePath }

  if (mimetype.startsWith('image/')) {
    const imageDetails = await processImage(stream, path)
    fileDetails = { ...fileDetails, ...imageDetails }
  } else if (mimetype.startsWith('video/')) {
    const videoDetails = await processVideo(stream, path)
    fileDetails = { ...fileDetails, ...videoDetails }
  } else if (mimetype.startsWith('audio/')) {
    const audioDetails = await processAudio(stream, path)
    fileDetails = { ...fileDetails, ...audioDetails }
  } else {
    await saveStreamToFile(stream, path)
  }

  const { size } = await fs.promises.stat(filePath)

  return { ...fileDetails, size }
}