From 1626c8cd3a6b8d2602641a7a3207a880cc116893 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Sat, 2 Sep 2023 09:15:50 -0700
Subject: [PATCH] macos: hacks for split focus to work correctly on macos 12

---
 macos/Sources/Ghostty/Ghostty.SplitView.swift | 13 +++++++++++++
 macos/Sources/Ghostty/Package.swift           |  4 ++++
 macos/Sources/Ghostty/SurfaceView.swift       | 15 +++++++++++++--
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/macos/Sources/Ghostty/Ghostty.SplitView.swift b/macos/Sources/Ghostty/Ghostty.SplitView.swift
index 553ede47f..9ea1a7351 100644
--- a/macos/Sources/Ghostty/Ghostty.SplitView.swift
+++ b/macos/Sources/Ghostty/Ghostty.SplitView.swift
@@ -322,6 +322,19 @@ extension Ghostty {
                 if previous != view {
                     _ = previous.resignFirstResponder()
                 }
+                
+                // On newer versions of macOS everything above works great so we're done.
+                if #available(macOS 13, *) { return }
+                
+                // On macOS 12, splits do not properly gain focus. I don't know why, but
+                // it seems like the `focused` SwiftUI method doesn't work. We use
+                // NotificationCenter as a blunt force instrument to make it work.
+                if #available(macOS 12, *) {
+                    NotificationCenter.default.post(
+                        name: Notification.didBecomeFocusedSurface,
+                        object: view
+                    )
+                }
             }
         }
     }
diff --git a/macos/Sources/Ghostty/Package.swift b/macos/Sources/Ghostty/Package.swift
index 7a09fd872..1b4517c22 100644
--- a/macos/Sources/Ghostty/Package.swift
+++ b/macos/Sources/Ghostty/Package.swift
@@ -91,6 +91,10 @@ extension Ghostty.Notification {
     /// Toggle fullscreen of current window
     static let ghosttyToggleFullscreen = Notification.Name("com.mitchellh.ghostty.toggleFullscreen")
     static let NonNativeFullscreenKey = ghosttyToggleFullscreen.rawValue
+    
+    /// Notification that a surface is becoming focused. This is only sent on macOS 12 to
+    /// work around bugs. macOS 13+ should use the ".focused()" attribute.
+    static let didBecomeFocusedSurface = Notification.Name("com.mitchellh.ghostty.didBecomeFocusedSurface")
 }
 
 // Make the input enum hashable.
diff --git a/macos/Sources/Ghostty/SurfaceView.swift b/macos/Sources/Ghostty/SurfaceView.swift
index 8448cb5d2..d6e885d55 100644
--- a/macos/Sources/Ghostty/SurfaceView.swift
+++ b/macos/Sources/Ghostty/SurfaceView.swift
@@ -54,7 +54,8 @@ extension Ghostty {
             // resize callback.
             GeometryReader { geo in
                 // We use these notifications to determine when the window our surface is
-                // attached to is or is not focused. 
+                // attached to is or is not focused.
+                let pubBecomeFocused = NotificationCenter.default.publisher(for: Notification.didBecomeFocusedSurface, object: surfaceView)
                 let pubBecomeKey = NotificationCenter.default.publisher(for: NSWindow.didBecomeKeyNotification)
                 let pubResign = NotificationCenter.default.publisher(for: NSWindow.didResignKeyNotification)
                 
@@ -74,6 +75,16 @@ extension Ghostty {
                             windowFocus = false
                         }
                     }
+                    .onReceive(pubBecomeFocused) { notification in
+                        // We only want to run this on older macOS versions where the .focused
+                        // method doesn't work properly. See the dispatch of this notification
+                        // for more information.
+                        if #available(macOS 13, *) { return }
+                        
+                        DispatchQueue.main.async {
+                            surfaceFocus = true
+                        }
+                    }
                     .onAppear() {
                         // Welcome to the SwiftUI bug house of horrors. On macOS 12 (at least
                         // 12.5.1, didn't test other versions), the order in which the view
@@ -119,7 +130,7 @@ extension Ghostty {
         /// The view to render for the terminal surface.
         let view: SurfaceView
         
-        /// This should be set to true wen the surface has focus. This is up to the parent because
+        /// This should be set to true when the surface has focus. This is up to the parent because
         /// focus is also defined by window focus. It is important this is set correctly since if it is
         /// false then the surface will idle at almost 0% CPU.
         let hasFocus: Bool