SIT314 A2 - iOS App

ViewController.swift

//
//  ViewController.swift
//  GPSTracker
//
//  Created by Perry Rose on 22/7/21.
//

import UIKit
import MapKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate {

    @IBOutlet weak var timerLabel: UILabel!
    @IBOutlet weak var statusLabel: UILabel!
    @IBOutlet weak var coordsRecordedLabel: UILabel!

    struct Coord: Codable {
        let lat: Double
        let lng: Double
    }
    
    var coords = [Coord]()
    var isTracking: Bool = false

    let locationManager = CLLocationManager()

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        
        // Request authorisation
        locationManager.requestAlwaysAuthorization()
        locationManager.requestWhenInUseAuthorization()
        
        // Set delegate
        if CLLocationManager.locationServicesEnabled() {
            locationManager.delegate = self
            locationManager.desiredAccuracy = kCLLocationAccuracyBest
        }
    }

    @IBAction func startTracking(_ sender: Any) {
        if (!isTracking) {
            // Start tracking user
            isTracking = true;
            statusLabel.text = "Current Status: Tracking"
            locationManager.startUpdatingLocation()
        }
    }
    
    func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
        // Alert user for any location errors
        alertUser(title: "Error", message: "There was an error getting your GPS data")
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if (isTracking) {
            if let location = locations.first {
                // Get current location and add it to coords array
                coords.append(Coord(lat: location.coordinate.latitude, lng: location.coordinate.longitude))
                // Update label
                coordsRecordedLabel.text = "Coord Recorded: \(coords.count)"
            }
        }
    }
    
    @IBAction func stopTracking(_ sender: Any) {
        if (isTracking) {
            // Stop Tracking
            isTracking = false;
            statusLabel.text = "Current Status: Not Tracking"
        }
    }
    
    @IBAction func clearTracking(_ sender: Any) {
        if (!isTracking) {
            // Remove coords from array
            coords.removeAll()
            coordsRecordedLabel.text = "Coords Recorded: 0"
            alertUser(title: "Success", message: "Your current tracking data has been removed")
        }
        else {
            alertUser(title: "Cannot clear tracking", message: "Please stop tracking before clearing tracking")
        }
    }
    
    @IBAction func exportCurrentRun(_ sender: Any) {
        if (!isTracking) {
            uploadData()
        }
        else {
            alertUser(title: "Cannot upload data", message: "Please stop the tracking before uploading the data")
        }
    }
    
    func uploadData() {
        // Encode run data
        guard let uploadData = try? JSONEncoder().encode(coords) else {
            alertUser(title: "Error", message: "There was an error with the JSON encoder")
            return
        }
        
        // Prepare request
        let url = URL(string: "https://api.jsonbin.io/v3/b")!
        var request = URLRequest(url: url)
        request.httpMethod = "POST"
        request.setValue("$2b$10$O3vibr5wNWg3eVTsg79HYO1Cs3Jcz7rJkwA6pf5phIVhDyVLwvctq", forHTTPHeaderField: "X-Master-Key")
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.setValue("GPSTrackingData", forHTTPHeaderField: "X-Bin-Name")
        
        // Upload JSON data
        let task = URLSession.shared.uploadTask(with: request, from: uploadData) { data, response, error in
            if error != nil {
                self.alertUser(title: "Cannot upload data", message: "There was an error uploading the data")
                return
            }
            guard let response = response as? HTTPURLResponse,
                (200...299).contains(response.statusCode) else {
                self.alertUser(title: "Cannot upload data", message: "There was a server error and the data was not uploaded")
                return
            }
            if let mimeType = response.mimeType,
                mimeType == "application/json",
                let data = data,
                let dataString = String(data: data, encoding: .utf8) {
                print(dataString)
                self.alertUser(title: "Success", message: "The data was successfully uploaded to JSONBIN.io")
            }
        }
        task.resume()
    }
    
    func alertUser(title: String, message: String) {
        // Alert on main thread to prevent errors from inside URLSession.shared.uploadTask call
        DispatchQueue.main.async {
            let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)
            alert.addAction(UIAlertAction(title: "Okay", style: .default, handler: nil))
            self.present(alert, animated: true)
        }
    }
    
}