import opts from 'config'
import Notifier from '@uci-utils/notify'
import Route53 from '@uci-utils/route53'
import pIp from 'public-ip'
import { lookup as clookup } from 'dns'
import { promisify } from 'util'
const lookup = promisify(clookup)
import { CronJob } from 'cron'
import to from 'await-to-js'
import { info } from 'console'

const rname = process.argv[2] || opts.domain
if (!rname) {
  console.log('exiting, must supply (sub)domain record name to check')
  console.log(JSON.stringify(opts, null, 3))
  process.exit()
}

const verbose = (opts.verbose ||'').length
const interval = (opts.lookup || {}).interval || 10 // seconds
const timeout = (opts.lookup || {}).timeout || 5  // minutes

if (verbose) console.log(JSON.stringify(opts, null, 3))

let notify=()=>{} // noop
const route53 = new Route53(opts.aws ? opts.aws : {profile:'default'})
;
(async () => {
  if (opts.notify){
    const notifier = await Notifier.create(opts.notify)
    notify = notifier.send.bind(notifier)
  }
  if (opts.cron && !opts.debug) {
    console.log('setting up check cron job every', opts.cron,'minutes')
    const cronstr = `0 */${opts.cron} * * * *`
    const job = new CronJob(cronstr, checkIP)
    console.log('cron job starting with:',cronstr)
    job.start()
  } else {
    console.log('running check a single time')
    checkIP()
  }

})().catch(err => {
  console.log('FATAL: IP Updater! \n',err)
  process.exitCode = 1
  process.kill(process.pid, 'SIGINT') // this will restart via systemd unit
})


async function checkIP () {
  let curr = await pIp.v4()
  if (opts.dev) {
    let ip = curr.split('.')
    ip[0] = ip[0] - Math.floor(Math.random() * 10)
    curr = ip.join('.')
    console.log('development run: generated dummy current ip', curr)
  }
  const saved =  await route53.getZoneRecordValue(rname)
  if (opts.debug) notify('checking for change in public ip',timestamp())
  if (curr !== saved)  {
    let msg=`${timestamp()} Network:${opts.network}, a new public ip has been detected for ${rname} from ${saved} to ${curr}`
    console.log(msg)
    notify(msg)
    const res=JSON.stringify(await route53.updateZoneRecordValue(rname,curr),null,3)
    console.log(res)
    notify(res)
    const fail = setTimeout(()=>{
      clearInterval(check)
      msg=`${timestamp()}, ${opts.network}: FATAL the pending change of ip address was not realized in ${timeout} minutes.  Human attention required`
      console.log(msg)
      notify(msg)
    },timeout*1000*60)
    const check = setInterval(async ()=>{
     let  [err,info] = await to(lookup(rname))
      if (err) {
        clearInterval(check)
        clearTimeout(fail)
        msg=`FATAL Error in lookup of' ${rname}, ${err}, aborting check, human intervention required`
        console.log(msg)
        notify(msg)
     } else {
      if (curr === info.address) {
        msg=`Update Succeeded, lookup of ${rname} is now ${curr}`
        clearInterval(check)
        clearTimeout(fail)
        console.log(msg)
        notify(msg)
      } else {
        msg=`Update Pending, will check again in ${interval} seconds`
        if (verbose || opts.debug ) {
          notify(msg)
          console.log(msg)
        }
      }
    }
    }
      ,interval*1000)

  } else console.log('Public IP has not changed, nothing to do',  saved)

}

function timestamp() {
  return new Date().toLocaleString().replace('T', ' ').substring(0, 19)
}