/*

 Copyright (C) 2016 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 View controller for the active workout screen.

 */

import Foundation

import UIKit

import HealthKit

import WatchConnectivity

class WorkoutViewController: UIViewController, WCSessionDelegate {

    // MARK: Properties

    var configuration : HKWorkoutConfiguration?

    let healthStore = HKHealthStore()

    var wcSessionActivationCompletion : ((WCSession)->Void)?

    @IBOutlet var workoutSessionState : UILabel!

    // MARK: UIViewController

    override func viewDidAppear(_ animated: Bool) {

        super.viewDidAppear(animated)

        startWatchApp()

    }

    // MARK: Convenience

    func startWatchApp() {

        guard let workoutConfiguration = configuration else { return }

        getActiveWCSession { (wcSession) in

            if wcSession.activationState == .activated && wcSession.isWatchAppInstalled {

                self.healthStore.startWatchApp(with: workoutConfiguration, completion: { (success, error) in

                    // Handle errors

                })

            }

        }

    }

    func getActiveWCSession(completion: @escaping (WCSession)->Void) {

        guard WCSession.isSupported() else { return }

        let wcSession = WCSession.default()

        wcSession.delegate = self

        if wcSession.activationState == .activated {

            completion(wcSession)

        } else {

            wcSession.activate()

            wcSessionActivationCompletion = completion

        }

    }

    func updateSessionState(_ state: String) {

        DispatchQueue.main.async {

            self.workoutSessionState.text = state

        }

    }

    // MARK: WCSessionDelegate

    func session(_ session: WCSession, activationDidCompleteWith activationState: WCSessionActivationState, error: Error?) {

        if activationState == .activated {

            if let activationCompletion = wcSessionActivationCompletion {

                activationCompletion(session)

                wcSessionActivationCompletion = nil

            }

        }

    }

    func session(_ session: WCSession, didReceiveMessage message: [String : Any]) {

        if let state = message["State"] as? String {

            updateSessionState(state)

        }

    }

    func sessionDidBecomeInactive(_ session: WCSession) {

    }

    func sessionDidDeactivate(_ session: WCSession) {

    }

}