/*

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

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 A view controller to display output from the magnetometer.

 */

import UIKit

import CoreMotion

import simd

class MagnetometerViewController: UIViewController, MotionGraphContainer {

    // MARK: Properties

    @IBOutlet weak var graphView: GraphView!

    // MARK: MotionGraphContainer properties

    var motionManager: CMMotionManager?

    @IBOutlet weak var updateIntervalLabel: UILabel!

    @IBOutlet weak var updateIntervalSlider: UISlider!

    let updateIntervalFormatter = MeasurementFormatter()

    @IBOutlet var valueLabels: [UILabel]!

    // MARK: UIViewController overrides

    override func viewDidLoad() {

        super.viewDidLoad()

        graphView.valueRanges = [-30.0...30.0, -250.0...250.0, -1000.0...1000.0]

    }

    override func viewWillAppear(_ animated: Bool) {

        super.viewWillAppear(animated)

        startUpdates()

    }

    override func viewDidDisappear(_ animated: Bool) {

        super.viewDidDisappear(animated)

        stopUpdates()

    }

    // MARK: Interface Builder actions

    @IBAction func intervalSliderChanged(_ sender: UISlider) {

        startUpdates()

    }

    // MARK: MotionGraphContainer implementation

    func startUpdates() {

        guard let motionManager = motionManager, motionManager.isGyroAvailable else { return }

        updateIntervalLabel.text = formattedUpdateInterval

        motionManager.magnetometerUpdateInterval = TimeInterval(updateIntervalSlider.value)

        motionManager.showsDeviceMovementDisplay = true

        motionManager.startMagnetometerUpdates(to: .main) { magnetometerData, error in

            guard let magnetometerData = magnetometerData else { return }

            let magneticField: double3 = [magnetometerData.magneticField.x, magnetometerData.magneticField.y, magnetometerData.magneticField.z]

            self.graphView.add(magneticField)

            self.setValueLabels(xyz: magneticField)

        }

    }

    func stopUpdates() {

        guard let motionManager = motionManager, motionManager.isAccelerometerAvailable else { return }

        motionManager.stopMagnetometerUpdates()

    }

}