const express = require('express')
const path = require('path')
const sqlite = require('sqlite')
const crypto = require('crypto')

const router = express.Router()
const cfgLoader = require(path.join('..', '..', 'config-loader'))(path.join(__dirname, 'config.json'), {
  database: 'shortened.db',
  gateway: 'https://distributed.icynet.eu',
  tokens: {}
})

async function init () {
  let config = await cfgLoader

  const dbPromise = Promise.resolve()
    .then(() => sqlite.open(path.join(__dirname, config.database), { Promise, cache: true }))
    .then(db => db.migrate({ migrationsPath: path.join(__dirname, 'migrations') }))

  router.get('/:hash', async (req, res, next) => {
    let db = await dbPromise
    let translation = await db.get('SELECT * FROM Translation WHERE translation = ?', req.params.hash)
    if (!translation) return res.status(404).end()

    res.header('Cache-Control', 'max-age=' + 7 * 24 * 60 * 60 * 1000)
    res.redirect(config.gateway + '/ipfs/' + translation.file_hash)
  })

  router.post('/publish', async (req, res, next) => {
    let token = req.header('token') || req.body.token
    if (!token || !config.tokens[token]) return res.status(402).send('Forbidden')

    let baseurl = config.tokens[token]
    let hash = req.query.hash || req.body.hash
    let filename = req.query.filename || req.body.filename
    if (!hash) return res.status(400).send('Invalid request: missing IPFS hash')
    if (!filename) filename = crypto.randomBytes(8).toString('hex')

    let db = await dbPromise
    await db.run('INSERT INTO Translation (translation,file_hash,timeat) VALUES (?,?,?)', filename, hash, new Date())

    res.send(baseurl + filename)
  })

  return router
}

module.exports = init