From ee651ae96a193f1307eaef4397a921a75a571bbf Mon Sep 17 00:00:00 2001
From: Shadowfacts <me@shadowfacts.net>
Date: Tue, 9 May 2023 16:42:16 -0400
Subject: [PATCH] Fix assorted issues collapsing/expanding split VC

---
 .../Main/MainSplitViewController.swift        | 34 +++++++++++++------
 .../HashtagTimelineViewController.swift       |  2 +-
 2 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/Tusker/Screens/Main/MainSplitViewController.swift b/Tusker/Screens/Main/MainSplitViewController.swift
index e580bd53..af2d2599 100644
--- a/Tusker/Screens/Main/MainSplitViewController.swift
+++ b/Tusker/Screens/Main/MainSplitViewController.swift
@@ -225,6 +225,7 @@ extension MainSplitViewController: UISplitViewControllerDelegate {
             // so that explore items aren't shown multiple times.
             
             let exploreNav = tabBarViewController.viewController(for: .explore) as! UINavigationController
+            // make sure there's a root ExploreViewController
             let explore: ExploreViewController
             if let existing = exploreNav.viewControllers.first as? ExploreViewController {
                 explore = existing
@@ -238,14 +239,23 @@ extension MainSplitViewController: UISplitViewControllerDelegate {
             explore.loadViewIfNeeded()
             
             let search = secondaryNavController.viewControllers.first as! InlineTrendsViewController
-            // Copy the search query from the search VC to the Explore VC's search controller.
-            let query = search.searchController.searchBar.text ?? ""
-            explore.searchController.searchBar.text = query
-            // Instruct the explore controller to show its search controller immediately upon its first appearance.
-            // explore.searchController.isActive can't be set directly, see FB7814561
-            explore.searchControllerStatusOnAppearance = !query.isEmpty
-            // Copy the results from the search VC's results controller to avoid the delay introduced by an extra network request
-            explore.resultsController.loadResults(from: search.resultsController)
+            if search.searchController.isActive {
+                // Copy the search query from the search VC to the Explore VC's search controller.
+                let query = search.searchController.searchBar.text ?? ""
+                explore.searchController.searchBar.text = query
+                // Instruct the explore controller to show its search controller immediately upon its first appearance.
+                // explore.searchController.isActive can't be set directly, see FB7814561
+                explore.searchControllerStatusOnAppearance = !query.isEmpty
+                // Copy the results from the search VC's results controller to avoid the delay introduced by an extra network request
+                explore.resultsController.loadResults(from: search.resultsController)
+            } else {
+                // if there is more than just the InlineTrendsVC, and the search VC is not active,
+                // then the user selected something from the trends screen
+                if secondaryNavController.viewControllers.count >= 2 {
+                    // make sure there's a corresponding trends VC in the collapsed nav that they can go back to
+                    exploreNav.pushViewController(TrendsViewController(mastodonController: mastodonController), animated: false)
+                }
+            }
             
             // Transfer the navigation stack, dropping the search VC, to keep anything the user has opened
             transferNavigationStack(from: .explore, to: exploreNav, dropFirst: true, append: true)
@@ -329,14 +339,16 @@ extension MainSplitViewController: UISplitViewControllerDelegate {
                         exploreItem = .favorites
                     case let listVC as ListTimelineViewController:
                         exploreItem = .list(listVC.list)
-                    case let hashtagVC as HashtagTimelineViewController:
+                    case let hashtagVC as HashtagTimelineViewController where hashtagVC.isHashtagSaved:
                         exploreItem = .savedHashtag(hashtagVC.hashtag)
                     case let instanceVC as InstanceTimelineViewController:
                         exploreItem = .savedInstance(instanceVC.instanceURL)
-                    case is TrendingStatusesViewController, is TrendingHashtagsViewController, is TrendingLinksViewController:
+                    case is TrendsViewController:
                         exploreItem = .explore
-                        // these three VCs are part of the root SearchViewController, so we don't need to transfer them
+                        // skip transferring the ExploreViewController and TrendsViewController
                         skipFirst = 2
+                        // prepend the InlineTrendsViewController
+                        toPrepend = getOrCreateNavigationStack(item: .explore).first!
                     default:
                         // transfer the navigation stack prepending, the existing explore VC
                         // if there was other stuff on the explore stack, it will get discarded
diff --git a/Tusker/Screens/Timeline/HashtagTimelineViewController.swift b/Tusker/Screens/Timeline/HashtagTimelineViewController.swift
index 9c404db8..e0b294d1 100644
--- a/Tusker/Screens/Timeline/HashtagTimelineViewController.swift
+++ b/Tusker/Screens/Timeline/HashtagTimelineViewController.swift
@@ -15,7 +15,7 @@ class HashtagTimelineViewController: TimelineViewController {
     
     var toggleSaveButton: UIBarButtonItem!
     
-    private var isHashtagSaved: Bool {
+    var isHashtagSaved: Bool {
         let req = SavedHashtag.fetchRequest(name: hashtag.name, account: mastodonController.accountInfo!)
         return mastodonController.persistentContainer.viewContext.objectExists(for: req)
     }