How to calculate ETA time with Google Maps API - Swift - swift

Question

I am drawing a route with Google map. I calculate the km distance on the route I drew. I also want to calculate how long it will go. How can I calculate how many minutes the route will take? I calculated the speed in the code below and when I tried to calculate the time using the speed I could not get any output. How can I calculate the duration?
func drowRoute(from source: CLLocationCoordinate2D, to destination: CLLocationCoordinate2D) {
self.mapView.clear()
let origin = "\(source.latitude),\(source.longitude)"
let destinationn = "\(destination.latitude),\(destination.longitude)"
guard let url = URL(string: "https://maps.googleapis.com/maps/api/directions/json?origin=\(origin)&destination=\(destinationn)&mode=driving&key=..") else {
let error = NSError(domain: "LocalDomain", code: 0, userInfo: [NSLocalizedDescriptionKey: "Failed to create object URL"])
print("Error: \(error)")
return
}
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let task = session.dataTask(with: url, completionHandler: {
(data, response, error) in
if error != nil {
print(error!.localizedDescription)
}
else {
do {
if let json : [String:Any] = try JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? [String: Any]{
guard let routes = json["routes"] as? NSArray else {
DispatchQueue.main.async {
}
return
}
if (routes.count > 0) {
let overview_polyline = routes[0] as? NSDictionary
let dictPolyline = overview_polyline?["overview_polyline"] as? NSDictionary
let points = dictPolyline?.object(forKey: "points") as? String
DispatchQueue.main.async {
//
let legs = overview_polyline?["legs"] as! Array<Dictionary<String, AnyObject>>
let distance = legs[0]["distance"] as? NSDictionary
let distanceValue = distance?["value"] as? Int ?? 0
let distanceDouleValue = distance?["value"] as? Double ?? 0.0
let duration = legs[0]["duration"] as? NSDictionary
let totalDurationInSeconds = duration?["value"] as? Int ?? 0
let durationDouleValue = duration?["value"] as? Double ?? 0.0
if(distanceValue != 0) {
self.speed = distanceDouleValue / durationDouleValue
print("speed", self.speed)
}
let miles = Double(distanceValue) / 1609.344
print("\(miles)")
let km = Double(distanceValue) * 0.001609
self.kmLabel.text = ("\(Int(km))" + " " + "KM")
if distanceValue > Int(32186.9){
}else{
self.showPath(polyStr: points!)
let startLocationDictionary = legs[0]["start_location"] as! Dictionary<String, AnyObject>
let originCoordinate = CLLocationCoordinate2DMake(startLocationDictionary["lat"] as! Double, startLocationDictionary["lng"] as! Double)
let endLocationDictionary = legs[legs.count - 1]["end_location"] as! Dictionary<String, AnyObject>
let destinationCoordinate = CLLocationCoordinate2DMake(endLocationDictionary["lat"] as! Double, endLocationDictionary["lng"] as! Double)
let marker1 = GMSMarker()
marker1.position = CLLocationCoordinate2D(latitude:destinationCoordinate.latitude, longitude: destinationCoordinate.longitude)
marker1.icon = UIImage(named: "placeholder")
marker1.map = self.mapView
let marker2 = GMSMarker()
marker2.position = CLLocationCoordinate2D(latitude:originCoordinate.latitude, longitude: originCoordinate.longitude)
marker2.icon = UIImage(named: "location")
marker2.map = self.mapView
}
}
}
else {
print(json)
DispatchQueue.main.async {
// SVProgressHUD.dismiss()
}
}
}
}
catch {
print("error in JSONSerialization")
DispatchQueue.main.async {
// SVProgressHUD.dismiss()
}
}
}
})
task.resume()
}
func showPath(polyStr :String){
// SVProgressHUD.dismiss()
let path = GMSPath(fromEncodedPath: polyStr)
let polyline = GMSPolyline(path: path)
polyline.strokeWidth = 5.0
polyline.strokeColor = UIColor.red
polyline.map = mapView
DispatchQueue.main.async {
let bounds = GMSCoordinateBounds(path: path!)
let update = GMSCameraUpdate.fit(bounds, with: UIEdgeInsets(top: 170, left: 30, bottom: 30, right: 30))
self.mapView.moveCamera(update)
}
}