Tag: list

So I have a view that shows the last 5 employees and 5 customers for a restaurant app. I save this in the user profile.

I also manage the currently selected object.

Here is my class.

//----------------------------------------------------------------------------------------
//----------------------------------------------------------------------------------------
//----------------------------------------------------------------------------------------
//This class is used for saving the user object and fetching the user object from user default
// user obejct can be Staff User or Customer object

enum RecentStaffErros : Error {
    case userObjectAddUpdateFailed
}

protocol RecentListManagable:FireCodable {
    var firstName: String? { get set }
    var lastName: String? { get set }
}

class RecentUserDataManager {

    var selectedData:T? = nil
    private let recentLimit = 5
    private(set) var recentUsers:(T) = ()
    private var userDefaultKey:UserDefaults.RecentUsersList.ArrayDefaultKey

    var recentUserDidChanged:(((T)) -> Void)?

    var isDataAvailable:Bool {
        return recentUsers.isEmpty
    }

    init(userDefaultKey:UserDefaults.RecentUsersList.ArrayDefaultKey) {
        self.userDefaultKey = userDefaultKey
        fetchLastFiveStaffUsersFromUserDefault()
    }

    private func fetchLastFiveStaffUsersFromUserDefault() {
        let staffUsers = UserDefaults.RecentUsersList.array(forKey: userDefaultKey) as? ((String:Any))
        self.recentUsers =   staffUsers?.map({ (object) -> T?  in
            if let staffData = object.data {
                return try? JSONDecoder().decode(T.self, from: staffData)
            }
            return nil
        }).compactMap{$0} ?? ()

    }

    private func saveLastFiveCustomerToUserDefault() {
        let arrayOfDictionary = self.recentUsers.map {$0.values}.compactMap{$0}
        UserDefaults.RecentUsersList.set(arrayOfDictionary, forKey: userDefaultKey)
    }

    func addOrUpdateStaffUserIfRequired(_ user:T) throws  {
        guard  let data = user.values else {
            throw RecentStaffErros.userObjectAddUpdateFailed
        }
        //we found the data remove from that index and append to bottom
        if let index =  recentUsers.firstIndex(where: {$0.id == user.id}) {
            self.recentUsers.remove(at: index)
        }
            //append new object
        self.recentUsers.insert(user, at: 0)


        if self.recentUsers.count > 5 {
            //keep only 5 users
            self.recentUsers = Array(self.recentUsers.prefix(recentLimit))
        }

        saveLastFiveCustomerToUserDefault()
        switchCurrentSelectedUser(user)
        self.recentUserDidChanged?(self.recentUsers)

    }

    func switchCurrentSelectedUser(_ user:T) {
        self.selectedData = user
    }

}

In my view controller, where I manage the list

 private var recentStaffUsers:RecentUserDataManager = RecentUserDataManager(userDefaultKey: .arrayStaffUsers)

 private var recentCustomerUsers:RecentUserDataManager = RecentUserDataManager(userDefaultKey: .arrayCustomerUser)




 private func setupForCustomer() {
        createButtonsForCustomer() //create 5 buttons 
        recentCustomerUsers.recentUserDidChanged = {(weak self) _ in
            DispatchQueue.main.async {
                //When New customer added or removed update Buttons
                self?.createButtonsForCustomer()
            }
        }
    }

Do you see any improvements or problems in my code?
I should think to redesign RecentUserDataManager deeper as separate logic