element-ios/Riot/Routers/NavigationRouterStore.swift

89 lines
3.9 KiB
Swift

//
// Copyright 2021-2024 New Vector Ltd.
//
// SPDX-License-Identifier: AGPL-3.0-only
// Please see LICENSE in the repository root for full details.
//
import Foundation
import WeakDictionary
/// `NavigationRouterStore` enables to get a NavigationRouter from a UINavigationController instance.
class NavigationRouterStore: NavigationRouterStoreProtocol {
// MARK: - Constants
static let shared = NavigationRouterStore()
// MARK: - Properties
// FIXME: WeakDictionary does not work with protocol
// Find a way to use NavigationRouterType as value
private var navigationRouters = WeakDictionary<UINavigationController, NavigationRouter>()
// MARK: - Setup
/// As we are ensuring that there is only one navigation controller per NavigationRouter, the class here should be used as a singleton.
private init() {
self.registerNavigationRouterNotifications()
}
// MARK: - Public
func navigationRouter(for navigationController: UINavigationController) -> NavigationRouterType {
if let existingNavigationRouter = self.findNavigationRouter(for: navigationController) {
return existingNavigationRouter
}
let navigationRouter = NavigationRouter(navigationController: RiotNavigationController())
return navigationRouter
}
// MARK: - Private
private func findNavigationRouter(for navigationController: UINavigationController) -> NavigationRouterType? {
return self.navigationRouters[navigationController]
}
private func removeNavigationRouter(for navigationController: UINavigationController) {
self.navigationRouters[navigationController] = nil
}
private func registerNavigationRouterNotifications() {
NotificationCenter.default.addObserver(self, selector: #selector(navigationRouterDidCreate(_:)), name: NavigationRouter.didCreate, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(navigationRouterWillDestroy(_:)), name: NavigationRouter.willDestroy, object: nil)
}
@objc private func navigationRouterDidCreate(_ notification: Notification) {
guard let userInfo = notification.userInfo,
let navigationRouter = userInfo[NavigationRouter.NotificationUserInfoKey.navigationRouter] as? NavigationRouterType,
let navigationController = userInfo[NavigationRouter.NotificationUserInfoKey.navigationController] as? UINavigationController else {
return
}
if let existingNavigationRouter = self.findNavigationRouter(for: navigationController) {
fatalError("\(existingNavigationRouter) is already tied to the same navigation controller as \(navigationRouter). We should have only one NavigationRouter per navigation controller")
} else {
// FIXME: WeakDictionary does not work with protocol
// Find a way to avoid this cast
self.navigationRouters[navigationController] = navigationRouter as? NavigationRouter
}
}
@objc private func navigationRouterWillDestroy(_ notification: Notification) {
guard let userInfo = notification.userInfo,
let navigationRouter = userInfo[NavigationRouter.NotificationUserInfoKey.navigationRouter] as? NavigationRouterType,
let navigationController = userInfo[NavigationRouter.NotificationUserInfoKey.navigationController] as? UINavigationController else {
return
}
if let existingNavigationRouter = self.findNavigationRouter(for: navigationController), existingNavigationRouter !== navigationRouter {
fatalError("\(existingNavigationRouter) is already tied to the same navigation controller as \(navigationRouter). We should have only one NavigationRouter per navigation controller")
}
self.removeNavigationRouter(for: navigationController)
}
}