import { apply, call, cancelled, put, take } from 'redux-saga/effects'

import { createSubscriptionChannel } from '../utils/websocket'
import { actions } from '../redux/errors'

import {toastr} from 'react-redux-toastr'

export default function *errorHandlingSaga({ socket }) {
  const errorChannel = yield call(createSubscriptionChannel, socket, '/user/queue/errors')
  try {
    while (true) {
      const error = yield take(errorChannel)
      yield* handleOneError(error)
    }
  } finally {
    if (yield cancelled()) {
      console.log('Error management saga cancelled')
      yield apply(errorChannel, errorChannel.close)
    }
  }
}

function *handleOneError(err) {
  console.error("Error received on web socket channel", err)
  const msg = buildMsg(err)
  yield apply(toastr, toastr.error, [msg, {icon: 'error'}])
  yield put(actions.errorReceived(err))
}

function buildMsg(err) {
  if (err.details.length > 0) {
    return err.details.map(d => d.message).join('\n')
  } else {
    return err.message
  }
}