From 6ac37faaa461cdfe09c88ef5e8194cbc4e932827 Mon Sep 17 00:00:00 2001
From: Ryan Walklin <ryan@testtoast.com>
Date: Fri, 12 Dec 2025 21:04:15 +1300
Subject: [PATCH] xdg_shell: float and position dragged toplevels

Make toplevels attached to an xdg-toplevel-drag automatically float, and
position them at the cursor when first mapped.

This enables the typical tab tear-off workflow:
1. User starts dragging a tab in a browser
2. Browser creates a new toplevel attached to the drag
3. Sway floats the toplevel and positions it at the cursor
4. The motion handler (from previous commit) keeps it moving with cursor
---
 sway/desktop/xdg_shell.c | 10 ++++++++++
 sway/tree/view.c         | 15 +++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/sway/desktop/xdg_shell.c b/sway/desktop/xdg_shell.c
index 48638817c..5428b9f6b 100644
--- a/sway/desktop/xdg_shell.c
+++ b/sway/desktop/xdg_shell.c
@@ -2,10 +2,13 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <wayland-server-core.h>
+#include <wlr/types/wlr_data_device.h>
 #include <wlr/types/wlr_xdg_shell.h>
+#include <wlr/types/wlr_xdg_toplevel_drag_v1.h>
 #include <wlr/types/wlr_xdg_toplevel_tag_v1.h>
 #include <wlr/util/edges.h>
 #include "log.h"
+#include "sway/server.h"
 #include "sway/decoration.h"
 #include "sway/scene_descriptor.h"
 #include "sway/desktop/transaction.h"
@@ -228,6 +231,13 @@ static void set_resizing(struct sway_view *view, bool resizing) {
 static bool wants_floating(struct sway_view *view) {
 	struct wlr_xdg_toplevel *toplevel = view->wlr_xdg_toplevel;
 	struct wlr_xdg_toplevel_state *state = &toplevel->current;
+
+	// Check if this toplevel is attached to a toplevel drag
+	if (wlr_xdg_toplevel_drag_v1_from_wlr_xdg_toplevel(
+			server.xdg_toplevel_drag_manager, toplevel) != NULL) {
+		return true;
+	}
+
 	return (state->min_width != 0 && state->min_height != 0
 		&& (state->min_width == state->max_width
 		|| state->min_height == state->max_height))
diff --git a/sway/tree/view.c b/sway/tree/view.c
index be813be98..71eb5bc68 100644
--- a/sway/tree/view.c
+++ b/sway/tree/view.c
@@ -8,10 +8,13 @@
 #include <wlr/types/wlr_foreign_toplevel_management_v1.h>
 #include <wlr/types/wlr_fractional_scale_v1.h>
 #include <wlr/types/wlr_output_layout.h>
+#include <wlr/types/wlr_cursor.h>
 #include <wlr/types/wlr_security_context_v1.h>
 #include <wlr/types/wlr_server_decoration.h>
 #include <wlr/types/wlr_subcompositor.h>
 #include <wlr/types/wlr_xdg_decoration_v1.h>
+#include <wlr/types/wlr_xdg_shell.h>
+#include <wlr/types/wlr_xdg_toplevel_drag_v1.h>
 #include <wlr/types/wlr_session_lock_v1.h>
 #if WLR_HAS_XWAYLAND
 #include <wlr/xwayland.h>
@@ -861,6 +864,18 @@ void view_map(struct sway_view *view, struct wlr_surface *wlr_surface,
 		view->container->pending.border = config->floating_border;
 		view->container->pending.border_thickness = config->floating_border_thickness;
 		container_set_floating(view->container, true);
+
+		// If this is a toplevel attached to a drag, position it at the cursor
+		if (view->wlr_xdg_toplevel != NULL) {
+			struct wlr_xdg_toplevel_drag_v1 *toplevel_drag =
+				wlr_xdg_toplevel_drag_v1_from_wlr_xdg_toplevel(
+					server.xdg_toplevel_drag_manager, view->wlr_xdg_toplevel);
+			if (toplevel_drag != NULL) {
+				double x = seat->cursor->cursor->x - toplevel_drag->x_offset;
+				double y = seat->cursor->cursor->y - toplevel_drag->y_offset;
+				container_floating_move_to(view->container, x, y);
+			}
+		}
 	} else {
 		view->container->pending.border = config->border;
 		view->container->pending.border_thickness = config->border_thickness;