From 5c3ec45a9552410f46c7173c46157c730ad2746b Mon Sep 17 00:00:00 2001
From: Sasikanth Miriyampalli <hello@sasikanth.dev>
Date: Mon, 16 Oct 2023 15:59:07 +0530
Subject: [PATCH] Provide UI view controller via application component

---
 iosApp/iosApp/AppDelegate.swift               | 39 ++++++++++++++++++-
 .../rss/reader/di/ApplicationComponent.kt     |  6 ++-
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/iosApp/iosApp/AppDelegate.swift b/iosApp/iosApp/AppDelegate.swift
index 44a09f726..88d2a40fb 100644
--- a/iosApp/iosApp/AppDelegate.swift
+++ b/iosApp/iosApp/AppDelegate.swift
@@ -14,7 +14,9 @@ import Sentry
 class AppDelegate: NSObject, UIApplicationDelegate {
 	let rootHolder: RootHolder = RootHolder()
     
-    lazy var applicationComponent: InjectApplicationComponent = InjectApplicationComponent()
+    lazy var applicationComponent: InjectApplicationComponent = InjectApplicationComponent(
+      uiViewControllerProvider: { UIApplication.topViewController()! }
+    )
     
     func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
 
@@ -67,3 +69,38 @@ class AppDelegate: NSObject, UIApplicationDelegate {
         }
     }
 }
+
+extension UIApplication {
+
+    private class func keyWindowCompat() -> UIWindow? {
+         return UIApplication
+             .shared
+             .connectedScenes
+             .flatMap { ($0 as? UIWindowScene)?.windows ?? [] }
+             .last { $0.isKeyWindow }
+     }
+
+    class func topViewController(
+        base: UIViewController? = UIApplication.keyWindowCompat()?.rootViewController
+    ) -> UIViewController? {
+        if let nav = base as? UINavigationController {
+            return topViewController(base: nav.visibleViewController)
+        }
+
+        if let tab = base as? UITabBarController {
+            let moreNavigationController = tab.moreNavigationController
+
+            if let top = moreNavigationController.topViewController, top.view.window != nil {
+                return topViewController(base: top)
+            } else if let selected = tab.selectedViewController {
+                return topViewController(base: selected)
+            }
+        }
+
+        if let presented = base?.presentedViewController {
+            return topViewController(base: presented)
+        }
+
+        return base
+    }
+}
diff --git a/shared/src/iosMain/kotlin/dev/sasikanth/rss/reader/di/ApplicationComponent.kt b/shared/src/iosMain/kotlin/dev/sasikanth/rss/reader/di/ApplicationComponent.kt
index 67a87894b..7eac7fd62 100644
--- a/shared/src/iosMain/kotlin/dev/sasikanth/rss/reader/di/ApplicationComponent.kt
+++ b/shared/src/iosMain/kotlin/dev/sasikanth/rss/reader/di/ApplicationComponent.kt
@@ -18,10 +18,14 @@ package dev.sasikanth.rss.reader.di
 import dev.sasikanth.rss.reader.di.scopes.AppScope
 import dev.sasikanth.rss.reader.repository.RssRepository
 import me.tatarka.inject.annotations.Component
+import me.tatarka.inject.annotations.Provides
+import platform.UIKit.UIViewController
 
 @AppScope
 @Component
-abstract class ApplicationComponent : SharedApplicationComponent() {
+abstract class ApplicationComponent(
+  @get:Provides val uiViewControllerProvider: () -> UIViewController,
+) : SharedApplicationComponent() {
 
   abstract val rssRepository: RssRepository
 }