fix: fix focus_follows_cursor on touchpads (#875)

packages/wm/src/common/platform/event_window.rs

@@ -34,7 +34,10 @@ use windows::Win32::{
 use super::{
   KeyboardHook, MouseMoveEvent, Platform, PlatformEvent, WindowEventHook,
 };
-use crate::{common::Point, user_config::KeybindingConfig};
+use crate::{
+  common::{platform::FOREGROUND_INPUT_IDENTIFIER, Point},
+  user_config::KeybindingConfig,
+};
 
 /// Global instance of sender for platform events.
 ///
@@ -266,13 +269,14 @@ fn handle_input_msg(
     )
   };
 
-  // Ignore if data is invalid or not a mouse event. The `hDevice` check
-  // ignores programmatic mouse inputs via `SendInput` (this caused issues
-  // since `NativeWindow::set_foreground` simulates a mouse input).
+  // Ignore if data is invalid or not a mouse event. Inputs from our own
+  // process are ignored, which would cause issues since
+  // `NativeWindow::set_foreground` simulates a mouse input.
   if res_size == 0
     || raw_input_size == u32::MAX
     || raw_input.header.dwType != RIM_TYPEMOUSE.0
-    || raw_input.header.hDevice.is_invalid()
+    || unsafe { raw_input.data.mouse.ulExtraInformation }
+      == FOREGROUND_INPUT_IDENTIFIER
   {
     return Ok(());
   }

packages/wm/src/common/platform/native_window.rs

@@ -18,7 +18,9 @@ use windows::{
       },
     },
     UI::{
-      Input::KeyboardAndMouse::{SendInput, INPUT, INPUT_MOUSE},
+      Input::KeyboardAndMouse::{
+        SendInput, INPUT, INPUT_0, INPUT_MOUSE, MOUSEINPUT,
+      },
       Shell::{ITaskbarList, TaskbarList},
       WindowsAndMessaging::{
         EnumWindows, GetClassNameW, GetWindow, GetWindowLongPtrW,
@@ -45,6 +47,10 @@ use crate::{
   windows::WindowState,
 };
 
+/// Magic number used to identify programmatic mouse inputs from our own
+/// process.
+pub const FOREGROUND_INPUT_IDENTIFIER: u32 = 6379;
+
 #[derive(Debug, Clone)]
 pub struct NativeWindow {
   pub handle: isize,
@@ -288,6 +294,12 @@ impl NativeWindow {
   pub fn set_foreground(&self) -> anyhow::Result<()> {
     let input = [INPUT {
       r#type: INPUT_MOUSE,
+      Anonymous: INPUT_0 {
+        mi: MOUSEINPUT {
+          dwExtraInfo: FOREGROUND_INPUT_IDENTIFIER as usize,
+          ..Default::default()
+        },
+      },
       ..Default::default()
     }];