require('dotenv').load()

const fs = require('fs')
const csv = require('csv-parse')
const es = require('event-stream')
const Datastore = require('nedb')
const BatchStream = require('batch-stream')

const db = new Datastore({ filename: process.env.DB_PATH, autoload: true })
const debug = require('debug')('setup')

function massage ([ipLo, ipHi, cc, country, area, city, lat, lng]) {
  return { ipLo, ipHi, cc, country, area, city, lat, lng }
}

function setup () {
  let qty = 0

  return new Promise((resolve, reject) => {
    fs.createReadStream(process.env.IP2LOCATION_PATH)
      // read and parse csv
      .pipe(csv())
      // batch it up
      .pipe(new BatchStream({ size: 100 }))
      // write it into the database
      .pipe(es.map((batch, cb) => {
        // massage and persist it
        db.insert(batch.map(massage), _ => {
          qty += batch.length
          if (qty % 100 === 0)
            debug(`Inserted ${qty} documents…`)
          cb.apply(this, arguments)
        })
      }))
      .on('end', resolve)
      .on('error', reject)
  })
}

module.exports = setup

if (!module.parent) {
  debug('Setting up geo database…')
  setup()
    .then(_ => debug('done!'))
    .catch(err => debug('there was an error :/', err))
}