temperature: per-device breakdown in panel, device filter config option

stats-daemon/src/temp.rs

@@ -1,25 +1,79 @@
+use std::collections::HashMap;
 use std::fs;
 use std::io::Write;
 
-pub fn read_temp_celsius() -> Option<i32> {
-    let mut max: Option<i32> = None;
+#[derive(Debug)]
+pub struct ThermalDevice {
+    pub name: String,
+    pub celsius: i32,
+}
+
+pub fn read_thermal_devices() -> Vec<ThermalDevice> {
+    let mut by_name: HashMap<String, i32> = HashMap::new();
+
     for i in 0.. {
-        let path = format!("/sys/class/thermal/thermal_zone{i}/temp");
-        match fs::read_to_string(&path) {
-            Ok(s) => {
-                if let Ok(millic) = s.trim().parse::<i32>() {
-                    let c = millic / 1000;
-                    max = Some(max.map_or(c, |m: i32| m.max(c)));
-                }
-            }
+        let temp_path = format!("/sys/class/thermal/thermal_zone{i}/temp");
+        let type_path = format!("/sys/class/thermal/thermal_zone{i}/type");
+
+        let temp_str = match fs::read_to_string(&temp_path) {
+            Ok(s) => s,
             Err(_) => break,
+        };
+
+        let millic: i32 = match temp_str.trim().parse() {
+            Ok(v) => v,
+            Err(_) => continue,
+        };
+        let celsius = millic / 1000;
+
+        let name = fs::read_to_string(&type_path)
+            .map(|s| s.trim().to_string())
+            .unwrap_or_else(|_| format!("zone{i}"));
+
+        // Keep the highest temp seen for each device type
+        let entry = by_name.entry(name).or_insert(celsius);
+        if celsius > *entry {
+            *entry = celsius;
         }
     }
-    max
+
+    let mut devices: Vec<ThermalDevice> = by_name
+        .into_iter()
+        .map(|(name, celsius)| ThermalDevice { name, celsius })
+        .collect();
+
+    // Sort descending by temp so the hottest shows first
+    devices.sort_by(|a, b| b.celsius.cmp(&a.celsius));
+    devices
 }
 
 pub fn emit_temp(out: &mut impl Write) {
-    if let Some(c) = read_temp_celsius() {
-        let _ = writeln!(out, "{{\"type\":\"temp\",\"celsius\":{c}}}");
+    let devices = read_thermal_devices();
+    if devices.is_empty() {
+        return;
     }
+
+    let max = devices.iter().map(|d| d.celsius).max().unwrap_or(0);
+
+    let devices_json: Vec<String> = devices
+        .iter()
+        .map(|d| {
+            format!(
+                "{{\"name\":{},\"celsius\":{}}}",
+                json_str(&d.name),
+                d.celsius
+            )
+        })
+        .collect();
+
+    let _ = writeln!(
+        out,
+        "{{\"type\":\"temp\",\"celsius\":{max},\"devices\":[{}]}}",
+        devices_json.join(",")
+    );
+}
+
+fn json_str(s: &str) -> String {
+    let escaped = s.replace('\\', "\\\\").replace('"', "\\\"");
+    format!("\"{escaped}\"")
 }