How do I know when my state changes form Auto-Renewable Subscription?

Hi,

I've the following class that handles everything regarding RevenueCat. My current problem is that I just don't get the current state of my subscription. So the point after purchase was clicked. Is it useful to have this class as a singleton like I've it here? Or rather as an EnvironmentObject?

If there's still missing information - please don't hesitate to ask.

 enum EUserSubscriptionState {
     case SUBSCRIBED
     case UNSUBSCRIBED
     case NONE
 }

enum EUserSubscriptionType {
    case TRIAL
    case BASIC
    case NONE
}

 class SubscriptionManager: ObservableObject {
     @Published var subscriptionType: EUserSubscriptionType = .NONE
     @Published var subscriptionState: EUserSubscriptionState = .NONE
     @Published var isSubscriptionSheetShown: Bool = false

     static let shared = SubscriptionManager()

     private init() {
         Purchases.shared.getCustomerInfo { info, error in
             guard let info = info, error == nil else { return }

             if info.entitlements.all["Basic"]?.isActive == true {
                 self.subscriptionState = .SUBSCRIBED
             } else {

             }
         }
     }

     var currentSubscriptionState: Bool {
         get {
             switch subscriptionState {
             case .SUBSCRIBED:
                 return true
             case .UNSUBSCRIBED:
                 return false
             case .NONE:
                 return false
             }
         }
     }

     func fetchPackage(completion: @escaping (Package) -> Void) {
         Purchases.shared.getOfferings { offerings, error in
             guard let offerings = offerings, error == nil else { return }

             guard let package = offerings.all.first?.value.availablePackages.first else { return }

             completion(package)
         }
     }

     func onSubscriptionClick() {
         fetchPackage { [weak self] package in
             self?.purchase(package: package)
             print("yyyy subscribed in click method")
         }
     }

     func purchase(package: Package) {
         Purchases.shared.purchase(package: package) { transaction, info, error, userCancelled in
             guard let transaction = transaction, let info = info, error == nil, !userCancelled else { return }
             print("yyyy subscribed in purchase")

             print("yyyy \(transaction)")
             print("yyyy \(info.entitlements)")
         }
     }

     func restorePurchases() {
         Purchases.shared.restorePurchases { info, error in
             guard let info = info, error == nil else { return }

             if info.entitlements.all["Basic"]?.isActive == true {
                 self.subscriptionState = .UNSUBSCRIBED

             } else {

             }
         }
     }

     func onTapHalfYearRestore() {
         restorePurchases()
     }
    func fetchCustomerSubscriptionState() {
         Purchases.shared.getCustomerInfo { info, error in
             guard let info = info, error == nil else { return }

             if info.entitlements.all["Basic"]?.isActive == true {
                 self.subscriptionState = .SUBSCRIBED
             } else {

             }
         }
     }
 }

extension AppDelegate: PurchasesDelegate {
    func purchases(_ purchases: Purchases, receivedUpdated customerInfo: CustomerInfo) {
        let subscriptionManager = SubscriptionManager.shared
        print("yyyy")
        if customerInfo.entitlements.all["Basic"]?.isActive == true {
            subscriptionManager.subscriptionState = .SUBSCRIBED
            subscriptionManager.subscriptionType = .BASIC
            print("yyyy basic subscribed")
        } else {
            subscriptionManager.subscriptionState = .UNSUBSCRIBED
            subscriptionManager.subscriptionType = .NONE
            print("unsubscribed basic subscribed")
        }
    }
}