space-ios/iOSClient/Extensions/UIViewController+Extension.swift

//
//  UIViewController+Extension.swift
//  Nextcloud
//
//  Created by Marino Faggiana on 02/08/2022.
//  Copyright © 2022 Marino Faggiana. All rights reserved.
//
//  Author Marino Faggiana <marino.faggiana@nextcloud.com>
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//

import Foundation

extension UIViewController {

    // https://stackoverflow.com/questions/6131205/how-to-find-topmost-view-controller-on-ios
    @objc func topMostViewController() -> UIViewController {
        // Handling Modal views
        if let presentedViewController = self.presentedViewController {
            return presentedViewController.topMostViewController()
        }
        // Handling UIViewController's added as subviews to some other views.
        else {
            for view in self.view.subviews {
                // Key property which most of us are unaware of / rarely use.
                if let subViewController = view.next {
                    if subViewController is UIViewController {
                        if let viewController = subViewController as? UIViewController {
                            return viewController.topMostViewController()
                        }
                    }
                }
            }
            return self
        }
    }

    // https://stackoverflow.com/questions/23620276/how-to-check-if-a-view-controller-is-presented-modally-or-pushed-on-a-navigation
    var isModal: Bool {
        if let index = navigationController?.viewControllers.firstIndex(of: self), index > 0 {
            return false
        } else if presentingViewController != nil {
            return true
        } else if navigationController?.presentingViewController?.presentedViewController == navigationController {
            return true
        } else if tabBarController?.presentingViewController is UITabBarController {
            return true
        } else {
            return false
        }
    }
}