Vuejs timeago filter (Milliseconds to Readable string)

vue-timeago-filter.js

/*
It converts timestamp / milliseconds to readable time ago string. for eg. 12 mins ago, 1 month ago
How to use?
import { timeago } from '@/filters.js';

export default {
    name: ...,
filters:{timeago},
}

in HTML
<div class="time">
{{post.date | timeago(ctime)}}
</div>

Then in main.js
  data: () => ({
  timer:null, ctime: Date.now()
  }),
  created(){
   this.timer = setInterval(() => {this.ctime = Date.now()}, 10000);
  },
  beforeDestroy(){
    clearInterval(this.timer)
    }
*/
export const timeago = (ptime, ctime) =>{
    if (!ptime || !ctime) return ''
        let ntime = new Date(ptime * 1000),
         seconds = Math.floor((ctime - ntime) / 1000),
             intervals = [Math.floor(seconds / 31536000), Math.floor(seconds / 2592000), Math.floor(seconds / 604800), 
                Math.floor(seconds / 86400), Math.floor(seconds / 3600),Math.floor(seconds / 60)
             ],
             times = ['year', 'month', 'week', 'day', 'hr', 'min'],
             key, res;
         for (key in intervals) {
             if (intervals[key] > 1){
                 res  = intervals[key] + ' ' + times[key] + 's ';
                 return res;
             }else if (intervals[key] === 1){
                 res = intervals[key] + ' ' + times[key] + ' ';
                 return res;
             }
         }
      return 'few secs';
}