ViewController.swift

//
//  ViewController.swift
//  mapanitest
//
//  Created by Julian Shen on 2016/10/4.
//  Copyright © 2016年 cowbay.wtf. All rights reserved.
//

import UIKit
import MapKit
import LocationPickerViewController

class ViewController: UIViewController, MKMapViewDelegate {
    @IBOutlet weak var mapView: MKMapView!
    
    
    var planePositionIndex:Int = 0
    var geodesicPolyline:MKGeodesicPolyline?
    let thePlane = MKPointAnnotation()
    var startloc, endloc: CLLocationCoordinate2D?
    var step:Int = 50
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        print("view did load")
        
        mapView.delegate = self
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func updatePlane() {
        planePositionIndex = planePositionIndex + step;
        
        if (planePositionIndex >= geodesicPolyline!.pointCount)
        {
            //plane has reached end, stop moving
            planePositionIndex = 0
            return;
        }
        
        let s = 8.0
        
        let nextMapPoint = geodesicPolyline?.points()[planePositionIndex]
        
        thePlane.coordinate = MKCoordinateForMapPoint(nextMapPoint!)
        
        mapView.region = MKCoordinateRegionMake(thePlane.coordinate, MKCoordinateSpan(latitudeDelta: s, longitudeDelta: s))

        perform(#selector(updatePlane), with: self, afterDelay: 0.4)
    }
    
    func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
        guard let polyline = overlay as? MKPolyline else {
            return MKOverlayRenderer()
        }
        
        let renderer = MKPolylineRenderer(polyline: polyline)
        renderer.lineWidth = 3.0
        renderer.alpha = 0.5
        renderer.strokeColor = UIColor.blue
        
        return renderer
    }
    
    func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
        let planeIdentifier = "Plane"
        
        let annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: planeIdentifier)
            ?? MKAnnotationView(annotation: annotation, reuseIdentifier: planeIdentifier)
        
        annotationView.image = UIImage(named: "ic_flight_48pt")
        
        return annotationView
    }
    
    @IBAction func pickLocation(_ sender: AnyObject) {
        let button = sender as! UIButton
        
        
        let locationPicker = LocationPicker()
        locationPicker.pickCompletion = { (pickedLocationItem) in
            // Do something with the location the user picked.
            print(pickedLocationItem.coordinate)
            print(button.accessibilityIdentifier)
            
            let coord = pickedLocationItem.coordinate!
            
            if button.accessibilityIdentifier == "startloc" {
                self.startloc = CLLocationCoordinate2D(latitude: coord.latitude, longitude: coord.longitude)
            } else if button.accessibilityIdentifier == "endloc" {
                self.endloc = CLLocationCoordinate2D(latitude: coord.latitude, longitude: coord.longitude)
            }
        }
        locationPicker.addBarButtons()
        
        let navigationController = UINavigationController(rootViewController: locationPicker)
            present(navigationController, animated: true) {
        }

        
    }
    
    @IBAction func displayPath(_ sender: AnyObject) {
        guard let sl = startloc else {
            print("error: no startloc")
            return
        }
        
        guard let el = endloc else {
            print("error: no endloc")
            return
        }
        
        let coordinates = [sl, el]
        
        if let gl = geodesicPolyline {
            mapView.remove(gl)
        }
        
        geodesicPolyline = MKGeodesicPolyline(coordinates: coordinates, count: 2)
        
        print(geodesicPolyline!.pointCount)
        step = geodesicPolyline!.pointCount/(Int)(20/0.4)
        mapView.add(geodesicPolyline!)
        
        thePlane.coordinate = sl
        
        mapView.addAnnotation(thePlane)
        
        UIView.animate(withDuration: 1.5) {
            let span = MKCoordinateSpanMake(8.0, 8.0)
            let region1 = MKCoordinateRegion(center: sl, span: span)
            self.mapView.setRegion(region1, animated: true)
            
            self.perform(#selector(self.updatePlane), with: self, afterDelay: 0.4)
        }
    }
}