From ea6698a2d8e34b50cf1686b71e2d0c02db715719 Mon Sep 17 00:00:00 2001
From: Shadowfacts <me@shadowfacts.net>
Date: Mon, 28 Nov 2022 16:33:19 -0500
Subject: [PATCH] State restoration for non-home timeline pages

---
 Tusker/Screens/Main/MainSplitViewController.swift  |  3 +--
 Tusker/Screens/Main/MainTabBarViewController.swift | 10 ++++------
 .../Screens/Timeline/TimelineViewController.swift  |  6 ++++--
 .../Timeline/TimelinesPageViewController.swift     | 14 ++++++++++----
 .../Utilities/SegmentedPageViewController.swift    |  7 ++++++-
 5 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/Tusker/Screens/Main/MainSplitViewController.swift b/Tusker/Screens/Main/MainSplitViewController.swift
index c69c6f458b..54f95580d6 100644
--- a/Tusker/Screens/Main/MainSplitViewController.swift
+++ b/Tusker/Screens/Main/MainSplitViewController.swift
@@ -391,8 +391,7 @@ extension MainSplitViewController: TuskerRootViewController {
             return tabBarViewController.stateRestorationActivity()
         } else {
             if let timelinePages = navigationStackFor(item: .tab(.timelines))?.first as? TimelinesPageViewController {
-                let timeline = timelinePages.pageControllers[timelinePages.currentIndex] as! TimelineViewController
-                return timeline.stateRestorationActivity()
+                return timelinePages.stateRestorationActivity()
             } else {
                 stateRestorationLogger.fault("MainSplitViewController: Unable to create state restoration activity")
                 return nil
diff --git a/Tusker/Screens/Main/MainTabBarViewController.swift b/Tusker/Screens/Main/MainTabBarViewController.swift
index 58b81f3cb0..d5ac1a9a31 100644
--- a/Tusker/Screens/Main/MainTabBarViewController.swift
+++ b/Tusker/Screens/Main/MainTabBarViewController.swift
@@ -244,9 +244,8 @@ extension MainTabBarViewController: TuskerRootViewController {
     func stateRestorationActivity() -> NSUserActivity? {
         let nav = viewController(for: .timelines) as! UINavigationController
         var activity: NSUserActivity?
-        if let timelinePages = nav.viewControllers.first as? TimelinesPageViewController,
-           let timelineVC = timelinePages.pageControllers[timelinePages.currentIndex] as? TimelineViewController {
-            activity = timelineVC.stateRestorationActivity()
+        if let timelinePages = nav.viewControllers.first as? TimelinesPageViewController {
+            activity = timelinePages.stateRestorationActivity()
         } else {
             stateRestorationLogger.fault("MainTabBarViewController: Unable to create state restoration activity, couldn't find timeline/page VC")
         }
@@ -268,12 +267,11 @@ extension MainTabBarViewController: TuskerRootViewController {
         
         if activity.activityType == UserActivityType.showTimeline.rawValue {
             let nav = viewController(for: .timelines) as! UINavigationController
-            guard let timelinePages = nav.viewControllers.first as? TimelinesPageViewController,
-                  let timelineVC = timelinePages.pageControllers[timelinePages.currentIndex] as? TimelineViewController else {
+            guard let timelinePages = nav.viewControllers.first as? TimelinesPageViewController else {
                 stateRestorationLogger.fault("MainTabBarViewController: Unable to restore timeline activity, couldn't find VC")
                 return
             }
-            timelineVC.restoreActivity(activity)
+            timelinePages.restoreActivity(activity)
             restoreEditedDraft()
         } else if activity.activityType == UserActivityType.newPost.rawValue {
             restoreEditedDraft()
diff --git a/Tusker/Screens/Timeline/TimelineViewController.swift b/Tusker/Screens/Timeline/TimelineViewController.swift
index 50281e0be8..58dea58f66 100644
--- a/Tusker/Screens/Timeline/TimelineViewController.swift
+++ b/Tusker/Screens/Timeline/TimelineViewController.swift
@@ -252,8 +252,10 @@ class TimelineViewController: UIViewController, TimelineLikeCollectionViewContro
     }
     
     private func doRestore() -> Bool {
-        guard let activity = activityToRestore,
-              let statusIDs = activity.userInfo?["statusIDs"] as? [String] else {
+        guard let activity = activityToRestore else {
+            return false
+        }
+        guard let statusIDs = activity.userInfo?["statusIDs"] as? [String] else {
             stateRestorationLogger.fault("TimelineViewController: activity missing statusIDs")
             return false
         }
diff --git a/Tusker/Screens/Timeline/TimelinesPageViewController.swift b/Tusker/Screens/Timeline/TimelinesPageViewController.swift
index e8ba32ef03..4219eccf3d 100644
--- a/Tusker/Screens/Timeline/TimelinesPageViewController.swift
+++ b/Tusker/Screens/Timeline/TimelinesPageViewController.swift
@@ -46,21 +46,27 @@ class TimelinesPageViewController: SegmentedPageViewController {
         fatalError("init(coder:) has not been implemented")
     }
     
+    func stateRestorationActivity() -> NSUserActivity? {
+        return (pageControllers[currentIndex] as! TimelineViewController).stateRestorationActivity()
+    }
+    
     func restoreActivity(_ activity: NSUserActivity) {
         guard let timeline = UserActivityManager.getTimeline(from: activity) else {
             return
         }
+        let index: Int
         switch timeline {
         case .home:
-            selectPage(at: 0, animated: false)
+            index = 0
         case .public(local: false):
-            selectPage(at: 1, animated: false)
+            index = 1
         case .public(local: true):
-            selectPage(at: 2, animated: false)
+            index = 2
         default:
             return
         }
-        let timelineVC = pageControllers[currentIndex] as! TimelineViewController
+        selectPage(at: index, animated: false)
+        let timelineVC = pageControllers[index] as! TimelineViewController
         timelineVC.restoreActivity(activity)
     }
 
diff --git a/Tusker/Screens/Utilities/SegmentedPageViewController.swift b/Tusker/Screens/Utilities/SegmentedPageViewController.swift
index 0e19512e68..ff3e8fdbf1 100644
--- a/Tusker/Screens/Utilities/SegmentedPageViewController.swift
+++ b/Tusker/Screens/Utilities/SegmentedPageViewController.swift
@@ -13,6 +13,7 @@ class SegmentedPageViewController: UIPageViewController, UIPageViewControllerDel
     let titles: [String]
     let pageControllers: [UIViewController]
     
+    private var initialIndex = 0
     private(set) var currentIndex = 0
     
     var segmentedControl: UISegmentedControl!
@@ -43,7 +44,7 @@ class SegmentedPageViewController: UIPageViewController, UIPageViewControllerDel
         
         view.backgroundColor = .systemBackground
         
-        selectPage(at: 0, animated: false)
+        selectPage(at: initialIndex, animated: false)
         
         addKeyCommand(MenuController.prevSubTabCommand)
         addKeyCommand(MenuController.nextSubTabCommand)
@@ -57,6 +58,10 @@ class SegmentedPageViewController: UIPageViewController, UIPageViewControllerDel
     }
     
     func selectPage(at index: Int, animated: Bool) {
+        guard isViewLoaded else {
+            initialIndex = index
+            return
+        }
         let direction: UIPageViewController.NavigationDirection = index - currentIndex > 0 ? .forward : .reverse
         setViewControllers([pageControllers[index]], direction: direction, animated: animated)
         navigationItem.title = pageControllers[index].title