Add ext-foreign-toplevel-list-v1 protocol

src/wayland/handlers/compositor.rs

@@ -265,6 +265,7 @@ impl State {
                     let res = shell.map_window(
                         &window,
                         &mut self.common.toplevel_info_state,
+                        &mut self.common.foreign_toplevel_list,
                         &mut self.common.workspace_state,
                         &self.common.event_loop_handle,
                     );

src/wayland/handlers/foreign_toplevel_list.rs

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+use crate::{
+    shell::{CosmicSurface, Shell},
+    state::State,
+};
+use smithay::wayland::foreign_toplevel_list::{
+    ForeignToplevelHandle, ForeignToplevelListHandler, ForeignToplevelListState,
+};
+use std::sync::Mutex;
+
+impl ForeignToplevelListHandler for State {
+    fn foreign_toplevel_list_state(&mut self) -> &mut ForeignToplevelListState {
+        &mut self.common.foreign_toplevel_list
+    }
+}
+
+pub fn new_foreign_toplevel(
+    window: &CosmicSurface,
+    foreign_toplevel_list: &mut ForeignToplevelListState,
+) {
+    let toplevel_handle =
+        foreign_toplevel_list.new_toplevel::<State>(window.title(), window.app_id());
+    *window
+        .user_data()
+        .get_or_insert::<Mutex<Option<ForeignToplevelHandle>>, _>(Default::default)
+        .lock()
+        .unwrap() = Some(toplevel_handle);
+}
+
+pub fn remove_foreign_toplevel(
+    window: &CosmicSurface,
+    foreign_toplevel_list: &mut ForeignToplevelListState,
+) {
+    if let Some(handle) = window
+        .user_data()
+        .get::<Mutex<Option<ForeignToplevelHandle>>>()
+    {
+        if let Some(handle) = handle.lock().unwrap().take() {
+            foreign_toplevel_list.remove_toplevel(&handle);
+        }
+    }
+}
+
+pub fn refresh_foreign_toplevels(shell: &Shell) {
+    for (window, _) in shell
+        .workspaces
+        .spaces()
+        .flat_map(|workspace| workspace.mapped())
+        .flat_map(|mapped| mapped.windows())
+    {
+        let foreign_toplevel_handle = window
+            .user_data()
+            .get::<Mutex<Option<ForeignToplevelHandle>>>()
+            .and_then(|handle| handle.lock().unwrap().clone());
+        if let Some(handle) = foreign_toplevel_handle {
+            let app_id = window.app_id();
+            let title = window.title();
+            if handle.app_id() != app_id || handle.title() != title {
+                handle.send_app_id(&app_id);
+                handle.send_title(&title);
+                handle.send_done();
+            }
+        }
+    }
+}
+
+smithay::delegate_foreign_toplevel_list!(State);

src/wayland/handlers/mod.rs

@@ -9,6 +9,7 @@ pub mod decoration;
 pub mod dmabuf;
 pub mod drm;
 pub mod drm_lease;
+pub mod foreign_toplevel_list;
 pub mod fractional_scale;
 pub mod idle_inhibit;
 pub mod idle_notify;

src/wayland/handlers/xdg_shell/mod.rs

@@ -379,6 +379,7 @@ impl XdgShellHandler for State {
                 surface.wl_surface(),
                 &seat,
                 &mut self.common.toplevel_info_state,
+                &mut self.common.foreign_toplevel_list,
             );
 
             let output = shell