gtk: always remember focused surface before grabbing focus

src/apprt/gtk/Paned.zig

@@ -86,6 +86,7 @@ pub fn setParent(self: *Paned, parent: Parent) void {
 pub fn focusSurfaceInPosition(self: *Paned, position: Position) void {
     const surface: *Surface = self.surfaceInPosition(position) orelse return;
     const widget = @as(*c.GtkWidget, @ptrCast(surface.gl_area));
+    surface.tab.focus_child = surface;
     _ = c.gtk_widget_grab_focus(widget);
 }
 

src/apprt/gtk/Surface.zig

@@ -836,6 +836,7 @@ fn gtkMouseDown(
     // If we don't have focus, grab it.
     const gl_widget = @as(*c.GtkWidget, @ptrCast(self.gl_area));
     if (c.gtk_widget_has_focus(gl_widget) == 0) {
+        self.tab.focus_child = self;
         _ = c.gtk_widget_grab_focus(gl_widget);
     }
 

src/apprt/gtk/Tab.zig

@@ -93,8 +93,6 @@ pub fn init(self: *Tab, window: *Window, parent_: ?*CoreSurface) !void {
     errdefer surface.deinit();
 
     self.child = Child{ .surface = surface };
-    // // TODO: this needs to change
-    self.focus_child = surface;
 
     // Add Surface to the Tab
     const gl_area_widget = @as(*c.GtkWidget, @ptrCast(surface.gl_area));
@@ -122,6 +120,9 @@ pub fn init(self: *Tab, window: *Window, parent_: ?*CoreSurface) !void {
         c.gtk_notebook_set_show_tabs(window.notebook, 1);
     }
 
+    // TODO: This needs to happen before we show the page
+    self.focus_child = surface;
+
     // Set the userdata of the box to point to this tab.
     c.g_object_set_data(@ptrCast(box_widget), GHOSTTY_TAB, self);
 

src/apprt/gtk/Window.zig

@@ -313,6 +313,10 @@ fn closeSurfaceInPaned(self: *Window, surface: *Surface, paned: *Paned, position
         },
     }
 
+    switch (sibling_child) {
+        .surface => |s| s.tab.focus_child = s,
+        else => {},
+    }
     const widget = @as(*c.GtkWidget, @ptrCast(sibling_widget));
     _ = c.gtk_widget_grab_focus(widget);
 }