const timer = {
      time: 0,
      timeStart: 0,
      timeEnd: 0,
      interval: 50,

      init: function() {
        this.timeStart = new Date();
      },

      setTimeStart: function() {
        if (this.timeStart == 0) {
          this.timeStart = Math.floor(Date.now() / 1000);
        }
      },

      start: function() {
        this.setTimeStart();

        var now = Math.floor(Date.now() / 1000); // get the time now
        var diff = now - this.timeStart; // diff in seconds between now and start

        // console.log('now', now);
        // console.log('timestart', this.timeStart);
        console.log('diff', diff);
        this.sync(diff);

        setTimeout(this.start(), this.interval * 1000); // set a timeout to update the timer
      },

      stop: function() {
        clearTimeout(this.start());
      },

      sync: function(time) {

      }
    };