user focused app

src-tauri/src/ufa/mod.rs

@@ -0,0 +1,54 @@
+/*
+UFA: User Focused App
+*/
+
+pub use types::*;
+mod icon_cache;
+#[cfg(target_os = "macos")]
+mod macos;
+mod types;
+#[cfg(target_os = "windows")]
+mod windows;
+
+/// Listens for changes in the active (foreground) application and calls the provided callback with metadata.
+/// The implementation varies by platform: macOS uses NSWorkspace notifications, Windows uses WinEventHook.
+pub fn init_listener<F>(callback: F)
+where
+    F: Fn(AppMeta) + Send + 'static,
+{
+    listen_impl(callback)
+}
+
+#[cfg(target_os = "macos")]
+fn listen_impl<F>(callback: F)
+where
+    F: Fn(AppMeta) + Send + 'static,
+{
+    macos::listen_for_active_app_changes(callback);
+}
+
+#[cfg(target_os = "windows")]
+fn listen_impl<F>(callback: F)
+where
+    F: Fn(AppMeta) + Send + 'static,
+{
+    windows::listen_for_active_app_changes(callback);
+}
+
+#[cfg(not(any(target_os = "macos", target_os = "windows")))]
+fn listen_impl<F>(_callback: F)
+where
+    F: Fn(AppMeta) + Send + 'static,
+{
+    // no-op on unsupported platforms
+}
+
+/// Initializes the foreground app change listener
+/// and emits events to the Tauri app on changes.
+/// Used for app to emit user foreground app to peers.
+pub fn init() {
+    init_listener(|meta: AppMeta| {
+        // TODO: Emit metadata to the app
+        println!("{:?}", meta);
+    });
+}