fix: fallback to sysfs for battery percentage on HID devices

Author: jamerrq

src/bluetooth.rs

@@ -6,6 +6,29 @@ use bluer::Device as BTDevice;
 
 use crate::app::AppResult;
 
+/// Fallback: read battery percentage from /sys/class/power_supply/ for devices
+/// that report battery via kernel drivers (e.g. PS4/PS5 controllers) instead of
+/// the Bluetooth Battery Service (BAS) profile exposed through BlueZ's Battery1
+/// D-Bus interface.
+fn read_battery_from_sysfs(addr: &Address) -> Option<u8> {
+    let addr_str = addr.to_string().to_lowercase();
+    let power_supply_dir = std::path::Path::new("/sys/class/power_supply");
+
+    if let Ok(entries) = std::fs::read_dir(power_supply_dir) {
+        for entry in entries.flatten() {
+            let name = entry.file_name();
+            let name_str = name.to_string_lossy();
+            if name_str.contains(&addr_str) {
+                let capacity_path = entry.path().join("capacity");
+                if let Ok(content) = std::fs::read_to_string(&capacity_path) {
+                    return content.trim().parse::<u8>().ok();
+                }
+            }
+        }
+    }
+    None
+}
+
 #[derive(Debug, Clone)]
 pub struct Controller {
     pub adapter: Arc<Adapter>,
@@ -114,7 +137,8 @@ impl Controller {
             let is_trusted = device.is_trusted().await?;
             let is_connected = device.is_connected().await?;
             let is_favorite = favorite_devices.contains(&addr);
-            let battery_percentage = device.battery_percentage().await?;
+            let battery_percentage =
+                device.battery_percentage().await?.or_else(|| read_battery_from_sysfs(&addr));
 
             let dev = Device {
                 device,