From 5903d7d10f8098146ab83c448f970d9eae993bab Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <m@mitchellh.com>
Date: Mon, 11 Aug 2025 09:43:39 -0700
Subject: [PATCH] apprt/gtk-ng: hook up goto_split

---
 src/apprt/gtk-ng/class/application.zig | 33 +++++++++++++++++++++++++-
 src/apprt/gtk-ng/class/split_tree.zig  | 17 +++++++++++++
 2 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/src/apprt/gtk-ng/class/application.zig b/src/apprt/gtk-ng/class/application.zig
index 7dde0fa93..129147ece 100644
--- a/src/apprt/gtk-ng/class/application.zig
+++ b/src/apprt/gtk-ng/class/application.zig
@@ -34,6 +34,7 @@ const Common = @import("../class.zig").Common;
 const WeakRef = @import("../weak_ref.zig").WeakRef;
 const Config = @import("config.zig").Config;
 const Surface = @import("surface.zig").Surface;
+const SplitTree = @import("split_tree.zig").SplitTree;
 const Window = @import("window.zig").Window;
 const CloseConfirmationDialog = @import("close_confirmation_dialog.zig").CloseConfirmationDialog;
 const ConfigErrorsDialog = @import("config_errors_dialog.zig").ConfigErrorsDialog;
@@ -552,6 +553,8 @@ pub const Application = extern struct {
 
             .desktop_notification => Action.desktopNotification(self, target, value),
 
+            .goto_split => return Action.gotoSplit(target, value),
+
             .goto_tab => return Action.gotoTab(target, value),
 
             .initial_size => return Action.initialSize(target, value),
@@ -615,7 +618,6 @@ pub const Application = extern struct {
             // TODO: splits
             .resize_split,
             .equalize_splits,
-            .goto_split,
             .toggle_split_zoom,
             => {
                 log.warn("unimplemented action={}", .{action});
@@ -1650,6 +1652,35 @@ const Action = struct {
         gio_app.sendNotification(n.body, notification);
     }
 
+    pub fn gotoSplit(
+        target: apprt.Target,
+        to: apprt.action.GotoSplit,
+    ) bool {
+        switch (target) {
+            .app => return false,
+            .surface => |core| {
+                // Design note: we can't use widget actions here because
+                // we need to know whether there is a goto target for returning
+                // the proper perform result (boolean).
+
+                const surface = core.rt_surface.surface;
+                const tree = ext.getAncestor(
+                    SplitTree,
+                    surface.as(gtk.Widget),
+                ) orelse {
+                    log.warn("surface is not in a split tree, ignoring goto_split", .{});
+                    return false;
+                };
+
+                return tree.goto(switch (to) {
+                    .previous => .previous_wrapped,
+                    .next => .next_wrapped,
+                    else => @panic("TODO"),
+                });
+            },
+        }
+    }
+
     pub fn gotoTab(
         target: apprt.Target,
         tab: apprt.action.GotoTab,
diff --git a/src/apprt/gtk-ng/class/split_tree.zig b/src/apprt/gtk-ng/class/split_tree.zig
index b70f0e2f8..cbaef54ae 100644
--- a/src/apprt/gtk-ng/class/split_tree.zig
+++ b/src/apprt/gtk-ng/class/split_tree.zig
@@ -258,6 +258,23 @@ pub const SplitTree = extern struct {
         self.setTree(&new_tree);
     }
 
+    /// Move focus from the currently focused surface to the given
+    /// direction. Returns true if focus switched to a new surface.
+    pub fn goto(self: *Self, to: Surface.Tree.Goto) bool {
+        const tree = self.getTree() orelse return false;
+        const active = self.getActiveSurfaceHandle() orelse return false;
+        const target = tree.goto(active, to) orelse return false;
+
+        // If we aren't changing targets then we did nothing.
+        if (active == target) return false;
+
+        // Get the surface at the target location and grab focus.
+        const surface = tree.nodes[target].leaf;
+        surface.grabFocus();
+
+        return true;
+    }
+
     fn disconnectSurfaceHandlers(self: *Self) void {
         const tree = self.getTree() orelse return;
         var it = tree.iterator();