import fs from 'fs/promises'
import path from 'path'

async function main() {
  // variable for incoming variable
  let mediaDir = ''
  let outputDir = ''
  let recurse = false

  // get command line arguments
  process.argv.forEach(function (val, index) {
    // console.log(index + ': ' + val)
    if (val == '-dir') {
      // console.log(process.argv[index + 1])
      mediaDir = process.argv[index + 1] || ''
    }

    if (val == '-r' || val == '-R') {
      recurse = true
    }

    if (val == '-o') {
      outputDir = process.argv[index + 1]
    }
  })

  // if no media dir jump out
  if (!mediaDir) {
    console.log('no directory passed to script')
    return 0
  }

  // read directory
  const media = await fs.readdir(mediaDir)

  // clean up directory for json
  let parent_dir = mediaDir
    .match(/(?<=\/)(\w|\d)+\/*$/i)[0]
    .replace(/\/$/i, '')

  if (!outputDir) {
    outputDir = '.'
  }

  const obj = await Promise.all(media.map(async m => {

    const _r = {
      title: '',
      parent_dir,
      media: m,
    }

    if (recurse) {
      const rDir = path.join(mediaDir, m)
      const files = await fs.readdir(rDir)

      _r.album = true
      _r.tracks = files
    }

    return _r
  }))

  const json = JSON.stringify(obj, null, 2)
  let output = `${parent_dir}.json`
  fs.writeFile(path.join(outputDir, output), json)
}


main()