macos: add reset zoom to all window titles

macos/Sources/Features/Terminal/BaseTerminalController.swift

@@ -758,6 +758,8 @@ class BaseTerminalController: NSWindowController,
         }
     }
 
+    func fullscreenDidChange() {}
+
     // MARK: Clipboard Confirmation
 
     @objc private func onConfirmClipboardRequest(notification: SwiftUI.Notification) {

macos/Sources/Features/Terminal/TerminalController.swift

@@ -145,7 +145,9 @@ class TerminalController: BaseTerminalController {
     }
 
 
-    func fullscreenDidChange() {
+    override func fullscreenDidChange() {
+        super.fullscreenDidChange()
+
         // When our fullscreen state changes, we resync our appearance because some
         // properties change when fullscreen or not.
         guard let focusedSurface else { return }

macos/Sources/Features/Terminal/Window Styles/TerminalWindow.swift

@@ -9,6 +9,9 @@ class TerminalWindow: NSWindow {
     /// used by the manual float on top menu item feature.
     static let defaultLevelKey: String = "TerminalDefaultLevel"
 
+    /// The view model for SwiftUI views
+    private var viewModel = ViewModel()
+
     /// The configuration derived from the Ghostty config so we don't need to rely on references.
     private(set) var derivedConfig: DerivedConfig?
 
@@ -19,6 +22,15 @@ class TerminalWindow: NSWindow {
 
     // MARK: NSWindow Overrides
 
+    override var toolbar: NSToolbar? {
+        didSet {
+            DispatchQueue.main.async {
+                // When we have a toolbar, our SwiftUI view needs to know for layout
+                self.viewModel.hasToolbar = self.toolbar != nil
+            }
+        }
+    }
+
     override func awakeFromNib() {
         guard let appDelegate = NSApp.delegate as? AppDelegate else { return }
 
@@ -43,6 +55,18 @@ class TerminalWindow: NSWindow {
             hideWindowButtons()
         }
 
+        // Create our reset zoom titlebar accessory.
+        let resetZoomAccessory = NSTitlebarAccessoryViewController()
+        resetZoomAccessory.layoutAttribute = .right
+        resetZoomAccessory.view = NSHostingView(rootView: ResetZoomAccessoryView(
+            viewModel: viewModel,
+            action: { [weak self] in
+                guard let self else { return }
+                self.terminalController?.splitZoom(self)
+            }))
+        addTitlebarAccessoryViewController(resetZoomAccessory)
+        resetZoomAccessory.view.translatesAutoresizingMaskIntoConstraints = false
+
         // Setup the accessory view for tabs that shows our keyboard shortcuts,
         // zoomed state, etc. Note I tried to use SwiftUI here but ran into issues
         // where buttons were not clickable.
@@ -115,6 +139,10 @@ class TerminalWindow: NSWindow {
             // Show/hide our reset zoom button depending on if we're zoomed.
             // We want to show it if we are zoomed.
             resetZoomTabButton.isHidden = !surfaceIsZoomed
+
+            DispatchQueue.main.async {
+                self.viewModel.isSurfaceZoomed = self.surfaceIsZoomed
+            }
         }
     }
 
@@ -313,3 +341,37 @@ class TerminalWindow: NSWindow {
         }
     }
 }
+
+// MARK: SwiftUI View
+
+extension TerminalWindow {
+    class ViewModel: ObservableObject {
+        @Published var isSurfaceZoomed: Bool = false
+        @Published var hasToolbar: Bool = false
+    }
+
+    struct ResetZoomAccessoryView: View {
+        @ObservedObject var viewModel: ViewModel
+        let action: () -> Void
+
+        var body: some View {
+            if viewModel.isSurfaceZoomed {
+                VStack {
+                    Button(action: action) {
+                        Image("ResetZoom")
+                            .foregroundColor(.accentColor)
+                    }
+                    .buttonStyle(.plain)
+                    .help("Reset Split Zoom")
+                    .frame(width: 20, height: 20)
+                    Spacer()
+                }
+                // With a toolbar, the window title is taller, so we need more padding
+                // to properly align.
+                .padding(.top, viewModel.hasToolbar ? 10 : 5)
+                // We always need space at the end of the titlebar
+                .padding(.trailing, 10)
+            }
+        }
+    }
+}

macos/Sources/Helpers/Fullscreen.swift

@@ -45,10 +45,6 @@ protocol FullscreenDelegate: AnyObject {
     func fullscreenDidChange()
 }
 
-extension FullscreenDelegate {
-    func fullscreenDidChange() {}
-}
-
 /// The base class for fullscreen implementations, cannot be used as a FullscreenStyle on its own.
 class FullscreenBase {
     let window: NSWindow
@@ -269,6 +265,12 @@ class NonNativeFullscreen: FullscreenBase, FullscreenStyle {
         window.styleMask = savedState.styleMask
         window.setFrame(window.frameRect(forContentRect: savedState.contentFrame), display: true)
 
+        // Removing the "titled" style also derefs all our accessory view controllers
+        // so we need to restore those.
+        for c in savedState.titlebarAccessoryViewControllers {
+            window.addTitlebarAccessoryViewController(c)
+        }
+
         // This is a hack that I want to remove from this but for now, we need to
         // fix up the titlebar tabs here before we do everything below.
         if let window = window as? TitlebarTabsVenturaTerminalWindow, window.titlebarTabs {
@@ -383,6 +385,7 @@ class NonNativeFullscreen: FullscreenBase, FullscreenStyle {
         let tabGroupIndex: Int?
         let contentFrame: NSRect
         let styleMask: NSWindow.StyleMask
+        let titlebarAccessoryViewControllers: [NSTitlebarAccessoryViewController]
         let dock: Bool
         let menu: Bool
 
@@ -394,6 +397,7 @@ class NonNativeFullscreen: FullscreenBase, FullscreenStyle {
             self.tabGroupIndex = window.tabGroup?.windows.firstIndex(of: window)
             self.contentFrame = window.convertToScreen(contentView.frame)
             self.styleMask = window.styleMask
+            self.titlebarAccessoryViewControllers = window.titlebarAccessoryViewControllers
             self.dock = window.screen?.hasDock ?? false
 
             if let cgWindowId = window.cgWindowId {