/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    A view controller that lists the most recent workouts.

*/

import UIKit

import AscentFramework

class WorkoutsController: UITableViewController {

    private var observerObject: NSObjectProtocol!

    private var workoutHistory = WorkoutHistory.load() {

        didSet {

            guard oldValue != workoutHistory && isViewLoaded else { return }

            tableView.reloadData()

        }

    }

    // MARK: Initialization

    required init?(coder aDecoder: NSCoder) {

        super.init(coder: aDecoder)

        // Add a notification handler for when the application becomes active.

        let notificationCenter = NotificationCenter.default

        notificationCenter.addObserver(forName: .UIApplicationDidBecomeActive, object: nil, queue: nil) { _ in

            self.workoutHistory = WorkoutHistory.load()

        }

    }

    deinit {

        let notificationCenter = NotificationCenter.default

        notificationCenter.removeObserver(observerObject)

    }

    // MARK: UITableViewDataSource

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

        return workoutHistory.count

    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        guard let cell = tableView.dequeueReusableCell(withIdentifier: WorkoutCell.reuseIdentifier, for: indexPath) as? WorkoutCell else { fatalError("Unable to dequeue a WorkoutCell") }

        let workout = self.workout(at: indexPath)

        cell.climbDescriptionLabel.text = workout.climbDescription

        cell.goalDescriptionLabel.text = workout.goalDescription

        cell.stateLabel.text = workout.stateDescription

        // Allow the user to select any active workouts.

        cell.selectionStyle = workout.state == .ended ? .none : .default

        return cell

    }

    // MARK: UITableViewDelegate

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

        tableView.deselectRow(at: indexPath, animated: true)

        // Determine the actions to show in an action sheet for the selected workout.

        let workout = self.workout(at: indexPath)

        let alertController = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)

        switch workout.state {

            case .active:

                let action = UIAlertAction(title: "Pause Workout", style: .default) { _ in

                    self.workoutHistory.pauseActiveWorkout()

                }

                alertController.addAction(action)

            case .paused:

                let action = UIAlertAction(title: "Resume Workout", style: .default) { _ in

                    self.workoutHistory.pauseActiveWorkout()

                }

                alertController.addAction(action)

            case .ended:

                return

        }

        alertController.addAction(UIAlertAction(title: "End Workout", style: .default) { _ in

            self.workoutHistory.endActiveWorkout()

        })

        alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel) { _ in })

        // Present the configured action sheet.

        present(alertController, animated: true, completion: nil)

    }

    // MARK: UIResponder

    override func restoreUserActivityState(_ activity: NSUserActivity) {

        super.restoreUserActivityState(activity)

        // Check this is an activity we can handle.

        guard let activityType = activity.ascentActivityType else { return }

        switch activityType {

            case .start(let workout):

                workoutHistory.start(newWorkout: workout)

            case .endWorkout, .cancelWorkout:

                workoutHistory.endActiveWorkout()

            case .pauseWorkout:

                workoutHistory.pauseActiveWorkout()

            case .resumeWorkout:

                workoutHistory.resumeActiveWorkout()

        }

    }

    // MARK: Convenience

    private func workout(at indexPath: IndexPath) -> Workout {

        let reversedWorkouts = workoutHistory.reversed()

        return reversedWorkouts[indexPath.row]

    }

}

class WorkoutCell: UITableViewCell {

    static let reuseIdentifier = "WorkoutCell"

    @IBOutlet weak var climbDescriptionLabel: UILabel!

    @IBOutlet weak var goalDescriptionLabel: UILabel!

    @IBOutlet weak var stateLabel: UILabel!

}