Add single-instance tauri plugin (#261)

Co-authored-by: lukas <lukas.walter@aceart.de>

src-tauri/src/main.rs

@@ -2,6 +2,8 @@
     all(not(debug_assertions), target_os = "windows"),
     windows_subsystem = "windows"
 )]
+
+use tauri::Manager;
 #[cfg(target_os = "macos")]
 mod menu;
 mod tray;
@@ -17,6 +19,23 @@ fn main() {
         .on_system_tray_event(tray::system_tray_handler);
 
     builder
+        .plugin(tauri_plugin_single_instance::init(|app, _, _| {
+            let tray_handle = match app.tray_handle_by_id(crate::tray::TRAY_LABEL) {
+                Some(h) => h,
+                None => return,
+            };
+            let window = app.get_window("main").unwrap();
+
+            if !window.is_visible().unwrap() || window.is_minimized().unwrap() {
+                window.unminimize().unwrap();
+                window.show().unwrap();
+                window.set_focus().unwrap();
+                tray_handle
+                    .get_item("toggle")
+                    .set_title("Hide Cinny")
+                    .unwrap();
+            }
+        }))
         .build(tauri::generate_context!())
         .expect("error while building tauri application")
         .run(run_event_handler)