GeolocationUtils.js

import Rx from 'rx'
import request from 'superagent'

export function getCurrentPosition(geolocationOptions = {enableHighAccuracy: true, timeout: 8000}) {
  if (!window.navigator && !window.navigator.geolocation) {
    throw new TypeError('geolocation not available')
  }

  return new Rx.AnonymousObservable((observer) => {
    window.navigator.geolocation.getCurrentPosition(
      (data) => {
        observer.onNext(data)
        observer.onCompleted()
      },
      observer.onError.bind(observer),
      geolocationOptions
    )
  })
}

export function findLocationByLatLng({lat, lng}) {
  return Rx.Observable.fromNodeCallback(request.get)(
      `https://maps.googleapis.com/maps/api/geocode/json?`
    + [
        `latlng=${lat},${lng}`,
        `sensor=false`
      ].join('&')
  )
}

export function findLocationByZip(zip = '') {
  return Rx.Observable.fromNodeCallback(request.get)(
      `https://maps.googleapis.com/maps/api/geocode/json?`
    + [
        `address=${zip}`,
        `components=country:USA`,
        `sensor=false`
      ].join('&')
  )
}

export function watchPosition(geolocationOptions) {
  if (!window.navigator && !window.navigator.geolocation) {
    throw new TypeError('geolocation not available')
  }

  return new Rx.AnonymousObservable((observer) => {
    var watchId = window.navigator.geolocation.watchPosition(
      observer.onNext.bind(observer),
      observer.onError.bind(observer),
      geolocationOptions
    )

    return () => {
      window.navigator.geolocation.clearWatch(watchId)
    }
  }).publish().refCount()
}