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var OfflineTrack,
  __bind = function(fn, me){ return function(){ return fn.apply(me, arguments); }; };

OfflineTrack = (function() {
  function OfflineTrack(dataSendFunc) {
    var e;
    this.dataSendFunc = dataSendFunc;
    this.pageVisibilityChanged = __bind(this.pageVisibilityChanged, this);
    this.doOnlineOfflineCheck = __bind(this.doOnlineOfflineCheck, this);
    this.sendData = __bind(this.sendData, this);
    this.endOfflineTrack = __bind(this.endOfflineTrack, this);
    this.setTrackingEnd = __bind(this.setTrackingEnd, this);
    this.startOfflineTrack = __bind(this.startOfflineTrack, this);
    try {
      this.trackingArray = JSON.parse(window.localStorage.getItem("offlineTrack")) || [];
    } catch (_error) {
      e = _error;
      return;
    }
    window.addEventListener("offline", this.startOfflineTrack, false);
    document.addEventListener("visibilitychange", this.pageVisibilityChanged, false);
    this.doOnlineOfflineCheck();
  }

  OfflineTrack.prototype.startOfflineTrack = function() {
    var lastTrack;
    if (this.isTracking) {
      return;
    }
    this.isTracking = true;
    lastTrack = this.trackingArray[this.trackingArray.length - 1];
    if ((lastTrack != null ? lastTrack.length : void 0) < 2) {
      this.trackingArray.splice(this.trackingArray.length - 1, 1);
    }
    this.trackingArray.push([Date.now()]);
    this.trackInterval = setInterval(this.setTrackingEnd, 30000);
    return window.addEventListener("online", this.endOfflineTrack, false);
  };

  OfflineTrack.prototype.setTrackingEnd = function() {
    var currentTrack;
    currentTrack = this.trackingArray[this.trackingArray.length - 1];
    currentTrack[1] = Date.now();
    return window.localStorage.setItem("offlineTrack", JSON.stringify(this.trackingArray));
  };

  OfflineTrack.prototype.endOfflineTrack = function() {
    this.isTracking = false;
    if (this.trackInterval) {
      clearInterval(this.trackInterval);
    }
    this.setTrackingEnd();
    window.removeEventListener("online", this.endOfflineTrack, false);
    return this.sendData();
  };

  OfflineTrack.prototype.sendData = function() {
    var mappedResults, result;
    if (this.trackingArray.length === 0) {
      return;
    }
    mappedResults = this.trackingArray.map(function(t) {
      return {
        start: new Date(t[0]),
        end: new Date(t[1])
      };
    });
    return result = this.dataSendFunc(mappedResults, (function(_this) {
      return function() {
        _this.trackingArray = [];
        return window.localStorage.removeItem("offlineTrack");
      };
    })(this));
  };

  OfflineTrack.prototype.doOnlineOfflineCheck = function() {
    if (navigator.onLine) {
      return this.sendData();
    } else {
      return this.startOfflineTrack();
    }
  };

  OfflineTrack.prototype.pageVisibilityChanged = function() {
    if (document.hidden && !navigator.onLine) {
      return this.endOfflineTrack();
    } else if (!navigator.onLine) {
      return this.startOfflineTrack();
    } else if (!document.hidden && navigator.onLine) {
      return this.sendData();
    }
  };

  return OfflineTrack;

})();

new OfflineTrack(function(data, cb) {
  console.log(data);
  return cb();
});