Add saved instances to new sidebar

Tusker/Screens/Main/MainSidebarViewController.swift

@@ -371,7 +371,7 @@ extension MainSidebarViewController {
             case let .savedInstance(url):
                 return url.host!
             case .addSavedInstance:
-                return "Find An Instance..."
+                return "Find an Instance..."
             }
         }
         

Tusker/Screens/Main/NewMainTabBarViewController.swift

@@ -25,6 +25,7 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
     private var myProfileTab: UITab!
     private var listsGroup: UITabGroup!
     private var hashtagsGroup: UITabGroup!
+    private var instancesGroup: UITabGroup!
     
     private var cancellables = Set<AnyCancellable>()
     
@@ -79,6 +80,17 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
         ]
         reloadHashtags()
         
+        instancesGroup = UITabGroup(title: "Instance Timelines", image: nil, identifier: Tab.instances.rawValue, children: []) { _ in
+            return AdaptableNavigationController()
+        }
+        instancesGroup.preferredPlacement = .sidebarOnly
+        instancesGroup.sidebarActions = [
+            UIAction(title: "Find an Instance…", image: UIImage(systemName: "plus"), handler: { [unowned self] _ in
+                self.showAddSavedInstance()
+            })
+        ]
+        reloadSavedInstances()
+        
         if UIDevice.current.userInterfaceIdiom == .phone {
             self.tabs = [
                 homeTab,
@@ -105,6 +117,8 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
                 .merge(with: NotificationCenter.default.publisher(for: .savedHashtagsChanged).map { _ in () })
                 .sink { [unowned self] in self.reloadHashtags() }
                 .store(in: &cancellables)
+            
+            NotificationCenter.default.addObserver(self, selector: #selector(reloadSavedInstances), name: .savedInstancesChanged, object: nil)
         }
         
         setupFastAccountSwitcher()
@@ -118,7 +132,7 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
             
             var exploreNavStack: [UIViewController]? = nil
             if let parent = selectedTab?.parent,
-               parent === listsGroup || parent === hashtagsGroup {
+               parent === listsGroup || parent === hashtagsGroup || parent === instancesGroup {
                 let nav = parent.viewController as! any NavigationControllerProtocol
                 exploreNavStack = nav.viewControllers
                 nav.viewControllers = []
@@ -180,6 +194,7 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
                 composeTab,
                 listsGroup,
                 hashtagsGroup,
+                instancesGroup,
             ]
             
             if let (tab, navStack) = newTabAndNavigationStack {
@@ -222,7 +237,7 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
             root = FavoritesViewController(mastodonController: mastodonController)
         case .myProfile:
             root = MyProfileViewController(mastodonController: mastodonController)
-        case .lists, .hashtags:
+        case .lists, .hashtags, .instances:
             fatalError("unreachable")
         }
         return embedInNavigationController(root)
@@ -279,6 +294,19 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
         hashtagsGroup.children = tabs
     }
     
+    @objc private func reloadSavedInstances() {
+        let viewControllerProvider = { [unowned self] (tab: UITab) in
+            let tab = tab as! InstanceTab
+            return InstanceTimelineViewController(for: tab.instance.url, parentMastodonController: self.mastodonController)
+        }
+        let req = SavedInstance.fetchRequest(account: mastodonController.accountInfo!)
+        req.sortDescriptors = [NSSortDescriptor(key: "url.host", ascending: true)]
+        let instances = (try? mastodonController.persistentContainer.viewContext.fetch(req).uniques(by: \.url)) ?? []
+        instancesGroup.children = instances.map {
+            InstanceTab(instance: $0, viewControllerProvider: viewControllerProvider)
+        }
+    }
+    
     @objc func handleComposeKeyCommand() {
         compose(editing: nil)
     }
@@ -305,6 +333,13 @@ final class NewMainTabBarViewController: BaseMainTabBarViewController {
         present(nav, animated: true)
     }
     
+    private func showAddSavedInstance() {
+        let findController = FindInstanceViewController(parentMastodonController: mastodonController)
+        findController.instanceTimelineDelegate = self
+        let nav = EnhancedNavigationViewController(rootViewController: findController)
+        present(nav, animated: true)
+    }
+    
     fileprivate func updateViewControllerSafeAreaInsets(_ vc: UIViewController) {
         guard vc is MultiColumnNavigationController || (vc as? AdaptableNavigationController)?.current is MultiColumnNavigationController else {
             return
@@ -379,6 +414,7 @@ extension NewMainTabBarViewController {
         
         case lists
         case hashtags
+        case instances
     }
 }
 
@@ -418,7 +454,7 @@ extension NewMainTabBarViewController: UITabBarControllerDelegate {
         // get the new transition animation.
         // This would be much less complicated if the controller just used the individual VCs of items in a group.
         if let group = newTab.parent,
-           group === listsGroup || group === hashtagsGroup,
+           group === listsGroup || group === hashtagsGroup || group === instancesGroup,
            let nav = group.viewController as? any NavigationControllerProtocol {
             updateViewControllerSafeAreaInsets(nav)
             
@@ -499,6 +535,9 @@ extension NewMainTabBarViewController: UITabBarController.Sidebar.Delegate {
             } else {
                 return nil
             }
+        } else if tab is InstanceTab {
+            // don't currently have a scene type for this
+            return nil
         } else if let tabID = Tab(rawValue: tab.identifier) {
             switch tabID {
             case .home:
@@ -517,7 +556,7 @@ extension NewMainTabBarViewController: UITabBarController.Sidebar.Delegate {
                 return nil
             case .compose:
                 activity = UserActivityManager.newPostActivity(accountID: id)
-            case .lists, .hashtags:
+            case .lists, .hashtags, .instances:
                 return nil
             }
         } else {
@@ -638,6 +677,20 @@ extension NewMainTabBarViewController: AccountSwitchableViewController {
     }
 }
 
+@available(iOS 18.0, *)
+extension NewMainTabBarViewController: InstanceTimelineViewControllerDelegate {
+    func didSaveInstance(url: URL) {
+        dismiss(animated: true) {
+            let tab = self.instancesGroup.tab(forIdentifier: InstanceTab.identifier(for: url))!
+            self.selectedTab = tab
+        }
+    }
+    
+    func didUnsaveInstance(url: URL) {
+        dismiss(animated: true)
+    }
+}
+
 private struct MyProfileContentConfiguration: UIContentConfiguration {
     let wrapped: any UIContentConfiguration
     @Box var view: UIView?
@@ -754,3 +807,21 @@ private class HashtagTab: UITab {
         "hashtag:\(name)"
     }
 }
+
+@available(iOS 18.0, *)
+private class InstanceTab: UITab {
+    let instance: SavedInstance
+    
+    init(instance: SavedInstance, viewControllerProvider: @escaping (UITab) -> UIViewController) {
+        self.instance = instance
+        super.init(title: instance.url.host!, image: UIImage(systemName: "globe"), identifier: Self.identifier(for: instance), viewControllerProvider: viewControllerProvider)
+    }
+    
+    static func identifier(for instance: SavedInstance) -> String {
+        "instance:\(instance.url.host!)"
+    }
+    
+    static func identifier(for instanceURL: URL) -> String {
+        "instance:\(instanceURL.host!)"
+    }
+}