macos: new terminal view new tab/window

macos/Sources/AppDelegate.swift

@@ -233,8 +233,7 @@ class AppDelegate: NSObject, ObservableObject, NSApplicationDelegate, GhosttyApp
     }
     
     private func focusedSurface() -> ghostty_surface_t? {
-        guard let window = NSApp.keyWindow as? PrimaryWindow else { return nil }
-        return window.focusedSurfaceWrapper.surface
+        return terminalManager.focusedSurface?.surface
     }
     
     private func splitMoveFocus(direction: Ghostty.SplitFocusDirection) {

macos/Sources/Features/Terminal/TerminalController.swift

@@ -9,6 +9,9 @@ class TerminalController: NSWindowController, NSWindowDelegate, TerminalViewDele
     /// The app instance that this terminal view will represent.
     let ghostty: Ghostty.AppState
     
+    /// The currently focused surface.
+    var focusedSurface: Ghostty.SurfaceView? = nil
+    
     init(_ ghostty: Ghostty.AppState) {
         self.ghostty = ghostty
         super.init(window: nil)
@@ -49,6 +52,13 @@ class TerminalController: NSWindowController, NSWindowDelegate, TerminalViewDele
         ))
     }
     
+    // Shows the "+" button in the tab bar, responds to that click.
+    override func newWindowForTab(_ sender: Any?) {
+        // Trigger the ghostty core event logic for a new tab.
+        guard let surface = self.focusedSurface?.surface else { return }
+        ghostty.newTab(surface: surface)
+    }
+    
     //MARK: - NSWindowDelegate
     
     func windowWillClose(_ notification: Notification) {
@@ -56,6 +66,10 @@ class TerminalController: NSWindowController, NSWindowDelegate, TerminalViewDele
     
     //MARK: - TerminalViewDelegate
     
+    func focusedSurfaceDidChange(to: Ghostty.SurfaceView?) {
+        self.focusedSurface = to
+    }
+    
     func titleDidChange(to: String) {
         self.window?.title = to
     }

macos/Sources/Features/Terminal/TerminalManager.swift

@@ -1,4 +1,5 @@
 import Cocoa
+import SwiftUI
 
 /// Manages a set of terminal windows.
 class TerminalManager {
@@ -8,6 +9,9 @@ class TerminalManager {
     
     let ghostty: Ghostty.AppState
     
+    /// The currently focused surface of the main window.
+    var focusedSurface: Ghostty.SurfaceView? { mainWindow?.controller.focusedSurface }
+    
     /// The set of windows we currently have.
     private var windows: [Window] = []
     
@@ -26,6 +30,30 @@ class TerminalManager {
     
     init(_ ghostty: Ghostty.AppState) {
         self.ghostty = ghostty
+        
+        let center = NotificationCenter.default
+        center.addObserver(
+            self,
+            selector: #selector(onNewTab),
+            name: Ghostty.Notification.ghosttyNewTab,
+            object: nil)
+        center.addObserver(
+            self,
+            selector: #selector(onNewWindow),
+            name: Ghostty.Notification.ghosttyNewWindow,
+            object: nil)
+    }
+    
+    deinit {
+        let center = NotificationCenter.default;
+        center.removeObserver(
+            self,
+            name: Ghostty.Notification.ghosttyNewTab,
+            object: nil)
+        center.removeObserver(
+            self,
+            name: Ghostty.Notification.ghosttyNewWindow,
+            object: nil)
     }
     
     /// Create a new terminal window.
@@ -43,6 +71,11 @@ class TerminalManager {
             return
         }
         
+        // Create a new window and add it to the parent
+        newTab(to: parent, withBaseConfig: base)
+    }
+    
+    private func newTab(to parent: NSWindow, withBaseConfig base: Ghostty.SurfaceConfiguration?) {
         // Create a new window and add it to the parent
         let window = createWindow(withBaseConfig: base).window!
         parent.addTabbedWindow(window, ordered: .above)
@@ -50,7 +83,7 @@ class TerminalManager {
     }
     
     /// Creates a window controller, adds it to our managed list, and returns it.
-    func createWindow(withBaseConfig: Ghostty.SurfaceConfiguration?) -> TerminalController {
+    private func createWindow(withBaseConfig: Ghostty.SurfaceConfiguration?) -> TerminalController {
         // Initialize our controller to load the window
         let c = TerminalController(ghostty)
         
@@ -59,4 +92,20 @@ class TerminalManager {
         
         return c
     }
+    
+    @objc private func onNewWindow(notification: SwiftUI.Notification) {
+        let configAny = notification.userInfo?[Ghostty.Notification.NewSurfaceConfigKey]
+        let config = configAny as? Ghostty.SurfaceConfiguration
+        self.newWindow(withBaseConfig: config)
+    }
+    
+    @objc private func onNewTab(notification: SwiftUI.Notification) {
+        guard let surfaceView = notification.object as? Ghostty.SurfaceView else { return }
+        guard let window = surfaceView.window else { return }
+        
+        let configAny = notification.userInfo?[Ghostty.Notification.NewSurfaceConfigKey]
+        let config = configAny as? Ghostty.SurfaceConfiguration
+        
+        self.newTab(to: window, withBaseConfig: config)
+    }
 }