//
//  UIViewController.swift
//  List
//
//  Created by Igor Danich on 30.06.2020.
//  Copyright © 2020 Igor Danich. All rights reserved.
//

import UIKit

extension UIViewController {
    static func loadFromNib() -> Self {
        func instantiateFromNib<T: UIViewController>() -> T {
            return T.init(nibName: String(describing: T.self), bundle: nil)
        }
        return instantiateFromNib()
    }
}

// MARK: - REFACTOR

extension UIViewController {
    func child<T: UIViewController>() -> T? { children.compactMap({ $0 as? T }).first }
    static func topController() -> UIViewController {
        let parentWindow: UIWindow?
        if #available(iOS 16.0, *), 
            let topWindow = UIApplication.shared.windows.last {
            parentWindow = topWindow
        } else {
            parentWindow = UIApplication.shared.windows.first
        }
        var parent: UIViewController! = parentWindow?.rootViewController
        while parent.presentedViewController != nil
            || (parent.presentationController?.presentedViewController != nil && parent.presentationController?.presentedViewController != parent) {
            parent = parent.presentedViewController ?? parent.presentationController?.presentedViewController
        }
        return parent
    }
}

extension UIView {
    var viewController: UIViewController? { (next as? UIViewController) ?? (next as? UIView)?.viewController }
}

extension UIViewController {
    private struct Keys {
        static var bag = "bag"
    }
    var bag: Notification.Bag {
        get {
            if let bag: Notification.Bag = Common.Runtime.object(self, key: &Keys.bag) {
                return bag
            } else {
                let bag = Notification.Bag()
                self.bag = bag
                return bag
            }
        }
        set { Common.Runtime.set(self, value: newValue, key: &Keys.bag) }
    }
}