Display on air state

src/main.rs

@@ -9,6 +9,7 @@ use std::{
     },
     collections::{
         HashMap,
+        HashSet,
     },
     rc::{
         Rc,
@@ -27,6 +28,8 @@ fn main() -> Result<()> {
     let nodes: Rc<RefCell<HashMap<u32, Box<dyn pw::proxy::ProxyT>>>> = Rc::new(RefCell::new(HashMap::new()));
     let listeners: Rc<RefCell<HashMap<u32, Vec<Box<dyn pw::proxy::Listener>>>>> = Rc::new(RefCell::new(HashMap::new()));
 
+    let running_cameras: Rc<RefCell<HashSet<u32>>> = Rc::new(RefCell::new(HashSet::new()));
+
     // Listen for new nodes
     let _registry_listener = registry
         .add_listener_local()
@@ -37,12 +40,34 @@ fn main() -> Result<()> {
 
                     let node: pw::node::Node = registry.bind(obj).unwrap();
 
+                    let running_cameras_weak = Rc::downgrade(&running_cameras);
+
                     // Listen for camera node changes
                     let node_listener = node
                         .add_listener_local()
-                        .info(|info| {
+                        .info(move |info| {
+
+                            if let Some(running_cameras) = running_cameras_weak.upgrade() {
+                                let cameras_are_running_before = running_cameras.borrow_mut().len() > 0;
+
+                                if let pw::node::NodeState::Running = info.state() {
+                                    running_cameras.borrow_mut().insert(info.id());
+                                }
+                                else {
+                                    running_cameras.borrow_mut().remove(&info.id());
+                                }
+
+                                let cameras_are_running_after = running_cameras.borrow_mut().len() > 0;
+                                if cameras_are_running_before != cameras_are_running_after {
+                                    if cameras_are_running_after {
+                                        println!("On air");
+                                    }
+                                    else {
+                                        println!("Off air");
+                                    }
+                                }
+                            }
 
-                            println!("{}: {:?}", info.id(), info.state());
                         })
                         .register();