text: var H5P = H5P || {};
  H5P.Summary = H5P.Summary || {};
  
  H5P.Summary.StopWatch = (function () {
    /**
     * @class {H5P.Summary.StopWatch}
     * @constructor
     */
    function StopWatch() {
      /**
       * @property {number} duration in ms
       */
      this.duration = 0;
    }
  
    /**
     * Starts the stop watch
     *
     * @public
     * @return {H5P.Summary.StopWatch}
     */
    StopWatch.prototype.start = function(){
      /**
       * @property {number}
       */
      this.startTime = Date.now();
      return this;
    };
  
    /**
     * Stops the stopwatch, and returns the duration in seconds.
     *
     * @public
     * @return {number}
     */
    StopWatch.prototype.stop = function(){
      this.duration = this.duration + Date.now() - this.startTime;
      return this.passedTime();
    };
  
    /**
     * Sets the duration to 0
     *
     * @public
     */
    StopWatch.prototype.reset = function(){
      this.duration = 0
    };
  
    /**
     * Returns the passed time in seconds
     *
     * @public
     * @return {number}
     */
    StopWatch.prototype.passedTime = function(){
      return Math.round(this.duration / 10) / 100;
    };
  
    return StopWatch;
  })();