Fix floating file chooser (#39154)

Closes #39117 

Some window managers (example: hyprland
https://github.com/hyprwm/Hyprland/issues/11229) still won't open a
floating file chooser because they don't support the XDG foreign
protocol yet: https://wayland.app/protocols/xdg-foreign-unstable-v2

Release Notes:

- Fixed file chooser not floating

---------

Co-authored-by: David Kleingeld <davidsk@zed.dev>

crates/gpui/src/platform/linux/platform.rs

@@ -73,6 +73,13 @@ pub trait LinuxClient {
     fn active_window(&self) -> Option<AnyWindowHandle>;
     fn window_stack(&self) -> Option<Vec<AnyWindowHandle>>;
     fn run(&self);
+
+    #[cfg(any(feature = "wayland", feature = "x11"))]
+    fn window_identifier(
+        &self,
+    ) -> impl Future<Output = Option<ashpd::WindowIdentifier>> + Send + 'static {
+        std::future::ready::<Option<ashpd::WindowIdentifier>>(None)
+    }
 }
 
 #[derive(Default)]
@@ -290,6 +297,9 @@ impl<P: LinuxClient + 'static> Platform for P {
         #[cfg(not(any(feature = "wayland", feature = "x11")))]
         let _ = (done_tx.send(Ok(None)), options);
 
+        #[cfg(any(feature = "wayland", feature = "x11"))]
+        let identifier = self.window_identifier();
+
         #[cfg(any(feature = "wayland", feature = "x11"))]
         self.foreground_executor()
             .spawn(async move {
@@ -300,6 +310,7 @@ impl<P: LinuxClient + 'static> Platform for P {
                 };
 
                 let request = match ashpd::desktop::file_chooser::OpenFileRequest::default()
+                    .identifier(identifier.await)
                     .modal(true)
                     .title(title)
                     .accept_label(options.prompt.as_ref().map(crate::SharedString::as_str))
@@ -346,6 +357,9 @@ impl<P: LinuxClient + 'static> Platform for P {
         #[cfg(not(any(feature = "wayland", feature = "x11")))]
         let _ = (done_tx.send(Ok(None)), directory, suggested_name);
 
+        #[cfg(any(feature = "wayland", feature = "x11"))]
+        let identifier = self.window_identifier();
+
         #[cfg(any(feature = "wayland", feature = "x11"))]
         self.foreground_executor()
             .spawn({
@@ -355,6 +369,7 @@ impl<P: LinuxClient + 'static> Platform for P {
                 async move {
                     let mut request_builder =
                         ashpd::desktop::file_chooser::SaveFileRequest::default()
+                            .identifier(identifier.await)
                             .modal(true)
                             .title("Save File")
                             .current_folder(directory)

crates/gpui/src/platform/linux/wayland/client.rs

@@ -7,6 +7,7 @@ use std::{
     time::{Duration, Instant},
 };
 
+use ashpd::WindowIdentifier;
 use calloop::{
     EventLoop, LoopHandle,
     timer::{TimeoutAction, Timer},
@@ -858,6 +859,20 @@ impl LinuxClient for WaylandClient {
     fn compositor_name(&self) -> &'static str {
         "Wayland"
     }
+
+    fn window_identifier(&self) -> impl Future<Output = Option<WindowIdentifier>> + Send + 'static {
+        async fn inner(surface: Option<wl_surface::WlSurface>) -> Option<WindowIdentifier> {
+            if let Some(surface) = surface {
+                ashpd::WindowIdentifier::from_wayland(&surface).await
+            } else {
+                None
+            }
+        }
+
+        let client_state = self.0.borrow();
+        let active_window = client_state.keyboard_focused_window.as_ref();
+        inner(active_window.map(|aw| aw.surface()))
+    }
 }
 
 impl Dispatch<wl_registry::WlRegistry, GlobalListContents> for WaylandClientStatePtr {

crates/gpui/src/platform/linux/x11/client.rs

@@ -1,5 +1,6 @@
 use crate::{Capslock, xcb_flush};
 use anyhow::{Context as _, anyhow};
+use ashpd::WindowIdentifier;
 use calloop::{
     EventLoop, LoopHandle, RegistrationToken,
     generic::{FdWrapper, Generic},
@@ -1652,6 +1653,16 @@ impl LinuxClient for X11Client {
 
         Some(handles)
     }
+
+    fn window_identifier(&self) -> impl Future<Output = Option<WindowIdentifier>> + Send + 'static {
+        let state = self.0.borrow();
+        state
+            .keyboard_focused_window
+            .and_then(|focused_window| state.windows.get(&focused_window))
+            .map(|window| window.window.x_window as u64)
+            .map(|x_window| std::future::ready(Some(WindowIdentifier::from_xid(x_window))))
+            .unwrap_or(std::future::ready(None))
+    }
 }
 
 impl X11ClientState {

crates/gpui/src/platform/linux/x11/window.rs

@@ -284,7 +284,7 @@ pub(crate) struct X11WindowStatePtr {
     pub state: Rc<RefCell<X11WindowState>>,
     pub(crate) callbacks: Rc<RefCell<Callbacks>>,
     xcb: Rc<XCBConnection>,
-    x_window: xproto::Window,
+    pub(crate) x_window: xproto::Window,
 }
 
 impl rwh::HasWindowHandle for RawWindow {