Implement power icon

src/upower.rs

@@ -0,0 +1,60 @@
+use cosmic::iced::{
+    futures::{channel::mpsc, SinkExt, StreamExt},
+    subscription, Subscription,
+};
+use std::any::TypeId;
+use tokio::time;
+use upower_dbus::UPowerProxy;
+use zbus::{Connection, Result};
+
+pub fn subscription() -> Subscription<Option<(String, f64)>> {
+    struct PowerSubscription;
+
+    subscription::channel(
+        TypeId::of::<PowerSubscription>(),
+        16,
+        |mut msg_tx| async move {
+            match handler(&mut msg_tx).await {
+                Ok(()) => {}
+                Err(err) => {
+                    log::warn!("upower error: {}", err);
+                    //TODO: send error
+                }
+            }
+
+            // If reading power status failed, clear power icon
+            msg_tx.send(None).await.unwrap();
+
+            //TODO: should we retry on error?
+            loop {
+                time::sleep(time::Duration::new(60, 0)).await;
+            }
+        },
+    )
+}
+
+//TODO: use never type?
+pub async fn handler(msg_tx: &mut mpsc::Sender<Option<(String, f64)>>) -> Result<()> {
+    let zbus = Connection::system().await?;
+    let upower = UPowerProxy::new(&zbus).await?;
+    let dev = upower.get_display_device().await?;
+
+    let mut icon_name_changed = dev.receive_icon_name_changed().await;
+    let mut percentage_changed = dev.receive_percentage_changed().await;
+    loop {
+        let mut info_opt = None;
+
+        if let Ok(percent) = dev.percentage().await {
+            if let Ok(icon_name) = dev.icon_name().await {
+                if !icon_name.is_empty() {
+                    info_opt = Some((icon_name, percent));
+                }
+            }
+        }
+
+        msg_tx.send(info_opt).await.unwrap();
+
+        // Waits until icon or percentage have changed
+        tokio::select!(_ = icon_name_changed.next() => (), _ = percentage_changed.next() => ());
+    }
+}