PermissionManager for swift permissions

PermissionManager.swift

//
//  PermissionManager.swift
//  IDRNDVoiceDemo
//
//  Created by Saurabh on 14/11/19.
//

import Foundation
import AVFoundation
import Speech

enum Permission {
    case camera
    case speech
    case audio
}

class PermissionManager {
    static let shared = PermissionManager()
    private var permissions: [Permission: Bool]
    
    private init() {
        permissions = [:]
    }
    
    private func askCameraPermission() {
        AVCaptureDevice.requestAccess(for: AVMediaType.video) {[weak self] response in
            self?.permissions[.camera] = response
        }
    }
    
    private func askSpeechPermission() {
        SFSpeechRecognizer.requestAuthorization {[weak self] authStatus in
            self?.permissions[.speech] = authStatus == .authorized
        }
    }
    
    private func askAudioPermissions() {
        AVAudioSession.sharedInstance().requestRecordPermission {[weak self] allowed in
            self?.permissions[.audio] = allowed
        }
    }
    
    func askPermissions(_ permissions: [Permission]) {
        for permission in permissions {
            askPermission(permission)
        }
    }
    
    func askPermission(_ permission: Permission) {
        switch permission {
            case .camera:
                askCameraPermission()
            case .speech:
                askSpeechPermission()
            case .audio:
                askAudioPermissions()
        }
    }
    
    subscript(permission: Permission) -> Bool {
        return permissions[permission] ?? false
    }
}