/*

 Copyright (C) 2017 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 Demonstrates the APIs to check and request access to health information.

 */

import Foundation

import HealthKit

class HealthAccessProvider {

    let healthStore = HKHealthStore()

}

extension HealthAccessProvider: PrivateDataAccessProvider {

    var accessLevel: PrivateDataAccessLevel {

        // Health data is not available on all devices.

        guard HKHealthStore.isHealthDataAvailable() else { return .unavailable }

        if let heartRateType = HKObjectType.quantityType(forIdentifier: .heartRate) {

            let authorizationStatus = healthStore.authorizationStatus(for: heartRateType)

            return authorizationStatus.accessLevel

        }

        return .undetermined

    }

    func requestAccess(completionHandler: @escaping (PrivateDataRequestAccessResult) -> Void) {

        // Health data is not available on all devices.

        guard HKHealthStore.isHealthDataAvailable() else {

            completionHandler(PrivateDataRequestAccessResult(.unavailable))

            return

        }

        if let heartRateType = HKObjectType.quantityType(forIdentifier: .heartRate) {

            let heartRateTypeSet: Set<HKQuantityType> = [heartRateType]

            //  Requests consent from the user to read and write heart rate data from the health store.

            healthStore.requestAuthorization(toShare: heartRateTypeSet, read: heartRateTypeSet) { (_, error) in

                if let error = error {

                    print(error)

                }

                DispatchQueue.main.async {

                    completionHandler(PrivateDataRequestAccessResult(self.accessLevel))

                }

            }

        }

    }

}

extension HKAuthorizationStatus: PrivateDataAccessLevelConvertible {

    var accessLevel: PrivateDataAccessLevel {

        switch self {

        case .notDetermined:

            return .undetermined

        case .sharingAuthorized:

            return .granted

        case .sharingDenied:

            return .denied

        }

    }

}