fix(wayland): scale portal pointer coordinates on niri (#15683)

* fix(wayland): scale portal pointer coordinates on niri

* perf(wayland): cache portal scaling desktop check

src/server/rdp_input.rs

@@ -9,7 +9,7 @@ use std::collections::HashMap;
 use std::sync::Arc;
 
 pub mod client {
-    use hbb_common::platform::linux::is_kde;
+    use hbb_common::platform::linux::{DISPLAY_DESKTOP_KDE, XDG_CURRENT_DESKTOP};
 
     use super::*;
 
@@ -302,6 +302,19 @@ pub mod client {
         }
     }
 
+    fn desktop_is_niri(desktop: &str) -> bool {
+        desktop
+            .split(':')
+            .any(|name| name.eq_ignore_ascii_case("niri"))
+    }
+
+    lazy_static::lazy_static! {
+        static ref SHOULD_SCALE_POINTER_COORDINATES: bool =
+            std::env::var(XDG_CURRENT_DESKTOP)
+                .map(|desktop| desktop == DISPLAY_DESKTOP_KDE || desktop_is_niri(&desktop))
+                .unwrap_or(false);
+    }
+
     pub struct RdpInputMouse {
         conn: Arc<SyncConnection>,
         session: Path<'static>,
@@ -327,7 +340,7 @@ pub mod client {
             // For Ubuntu 24.04(Gnome 46), (x,y) is restricted from (0,0) to (400,300), but the actual range in screen is:
             // Logic coordinate from (0,0) to (200x150).
             // Or physical coordinate from (0,0) to (400,300).
-            let scale = if is_kde() {
+            let scale = if *SHOULD_SCALE_POINTER_COORDINATES {
                 if resolution.0 == 0 || stream.get_size().0 == 0 {
                     Some(1.0f64)
                 } else {
@@ -348,6 +361,19 @@ pub mod client {
         }
     }
 
+    #[cfg(test)]
+    mod tests {
+        use super::desktop_is_niri;
+
+        #[test]
+        fn detects_niri_in_desktop_list() {
+            assert!(desktop_is_niri("niri"));
+            assert!(desktop_is_niri("NIRI"));
+            assert!(desktop_is_niri("GNOME:niri"));
+            assert!(!desktop_is_niri("GNOME"));
+        }
+    }
+
     impl MouseControllable for RdpInputMouse {
         fn as_any(&self) -> &dyn std::any::Any {
             self