/*

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

See LICENSE.txt for this sample’s licensing information

Abstract:

This class represents a significant activity the user performed.

*/

import Foundation

import CoreMotion

/**

    This struct is responsible for storing the activity data and providing relevant

    pedometer properties such as pace and distance.

*/

struct Activity: CustomDebugStringConvertible {

    // MARK: Properties

    static let milesPerMeter = 0.000621371192

    var activity: CMMotionActivity

    var startDate: Date

    var endDate: Date

    var timeInterval = 0.0

    var numberOfSteps: Int?

    var distance: Int?

    var floorsAscended: Int?

    var floorsDescended: Int?

    // MARK: Initializers

    init(activity: CMMotionActivity, startDate: Date, endDate: Date, pedometerData: CMPedometerData? = nil) {

        self.activity = activity

        self.startDate = startDate

        self.endDate = endDate

        self.timeInterval = endDate.timeIntervalSince(startDate)

        guard let pedometerData = pedometerData , activity.walking || activity.running else {

            return

        }

        numberOfSteps = pedometerData.numberOfSteps.intValue

        if let distance = pedometerData.distance?.intValue , distance > 0 {

            self.distance = distance

        }

        if let floorsAscended = pedometerData.floorsAscended?.intValue {

            self.floorsAscended = floorsAscended

        }

        if let floorsDescended = pedometerData.floorsDescended?.intValue {

            self.floorsDescended = floorsDescended

        }

    }

    // MARK: Computed Properties

    var activityType: String {

        if activity.walking {

            return "Walking"

        }

        else if activity.running {

            return "Running"

        }

        else if activity.automotive {

            return "Automotive"

        }

        else if activity.cycling {

            return "Cycling"

        }

        else if activity.stationary {

            return "Stationary"

        }

        else {

            return "Unknown"

        }

    }

    var startDateDescription: String {

        return createLocalTimeDateStringFromDate(startDate)

    }

    var endDateDescription: String {

        return createLocalTimeDateStringFromDate(endDate)

    }

    var activityDuration: String {

        return createTimeStringFromSeconds(timeInterval)

    }

    var distanceInMiles: String {

        guard let distance = distance else { return "N/A" }

        return String(format: "%.7f", Double(distance) * Activity.milesPerMeter)

    }

    var calculatedPace: String {

        guard let distance = distance else { return "N/A" }

        let miles = Double(distance) * Activity.milesPerMeter

        let paceInSecondsPerMile = timeInterval / miles

        return createTimeStringFromSeconds(paceInSecondsPerMile)

    }

    // MARK: Helper Functions

    fileprivate func createTimeStringFromSeconds(_ seconds: TimeInterval) -> String {

        let calendar = NSCalendar.current

        let startDate = Date()

        let endDate = Date(timeInterval: seconds, since: startDate)

        let unitFlags: NSCalendar.Unit = [.hour, .minute, .second]

        let conversionInfo = (calendar as NSCalendar).components(unitFlags, from: startDate, to: endDate, options: [])

        return String(format: "%dh %dm %ds", conversionInfo.hour!, conversionInfo.minute!, conversionInfo.second!)

    }

    fileprivate func createLocalTimeDateStringFromDate(_ date: Date) -> String {

        return DateFormatter.localizedString(from: date, dateStyle: .medium, timeStyle: .medium)

    }

    // MARK: CustomDebugStringConvertible

    var debugDescription: String {

        return "ActivityType: \(activityType), StartDate: \(startDate), EndDate: \(endDate), TimeInterval: \(timeInterval), Steps: \(numberOfSteps), Distance: \(distance), FloorsAscended: \(floorsAscended), FloorsDescended: \(floorsDescended) "

    }

}