Should show tutorial

AppManager+Tutorial.swift

public class AppManager: NSObject {
    
    static let userDefaults = UserDefaults.standard
    static let shared = AppManager()
    static let dataKey = "AppManagerDataKey"
    static let tutorialKey = "AppManagerTutorialKey"
    
    public func reset(for key: String) {
        if var data = userDefaults.object(forKey: dataKey) as? [String: Bool] {
            data.removeValue(forKey: key)
            userDefaults.set(data, forKey: dataKey)
        }
    }
    
    public func shouldShowTutorial() -> Bool {
        if var data = userDefaults.object(forKey: dataKey) as? [String: Bool] {
            if let _ = data[tutorialKey] {
                return false
            }
            data[tutorialKey] = true
            userDefaults.set(data, forKey: dataKey)
            return true
        }
        let data = [tutorialKey: true]
        userDefaults.set(data, forKey: dataKey)
        return true
    }
}