metric: don't hardcode battery name

bl: red background if battery is low

blinkenlicht/bl.fnl

@@ -86,12 +86,13 @@
                :wait-for { :interval (* 1000 10) }
                :refresh
                #(let [{:power-supply-capacity percent
-                       :power-supply-status status} (metric.battery)
+                       :power-supply-status status}
+                      (metric.battery "axp20x-battery")
                       icon-code (battery-icon-codepoint
                                  status (tonumber percent))]
                   {:text
                    (string.format "%s %d%%" (utf8.char icon-code) percent)
-                   :classes ["yellow"]
+                   :classes ["battery" (if (< (tonumber percent) 20) "low" "ok")]
                    })
                })
    (indicator {

blinkenlicht/licht.css

@@ -7,6 +7,10 @@
     margin: 5px 0px 5px 12px;
 }
 
+.battery.low {
+    background-color: #e00;
+}
+
 .bar {
     background-color: #200;
 }

blinkenlicht/metric.fnl

@@ -6,8 +6,8 @@
           (one five fifteen) (line:match "([%d.]+) +([%d.]+) +([%d.]+)")]
       (values (tonumber one) (tonumber five) (tonumber fifteen)))))
 
-(fn battery [path]
-  (let [name (.. (or path "/sys/class/power_supply/BAT0") "/uevent")]
+(fn battery [name]
+  (let [name (.. "/sys/class/power_supply/" name  "/uevent")]
     (with-open [f (io.open name :r)]
       (let [fields {}]
         (each [line #(f:read "*l")]