add brightness service and slider

widgets/bar/__init__.hy

@@ -6,6 +6,7 @@
 (import .clock [clock])
 (import .battery [battery-dial])
 (import .volume [volume])
+(import .brightness [brightness])
 
 (setv bar (Widget.Window
   :namespace "bar"
@@ -26,7 +27,8 @@
           :class-name "sliders"
           :vertical True
           :children [
-            volume])
+            volume
+            brightness])
         battery-dial
         ((astalify Gtk.Separator))
         clock]))))

widgets/bar/brightness.hy

@@ -0,0 +1,22 @@
+(import astal *)
+(import astal.gtk3 *)
+(import services.brightness [Brightness])
+(import math [floor])
+
+(import gi.repository [AstalWp])
+
+(let [
+  backlight (Brightness "amdgpu_bl1")]
+  (setv brightness (Widget.Box
+    :class-name "brightness-slider"
+    :children [
+      (Widget.Button
+        :child (Widget.Icon :icon (bind backlight "brightness" (fn [brightness]
+          f"display-brightness-{(get ["off" "low" "medium" "high" "high"] (floor (/ (* brightness 100) 25)))}-symbolic"))))
+      (Widget.Slider
+        :class-name "brightness-slider"
+        :hexpand True
+        :draw-value False
+        :value (bind backlight "brightness")
+        :on-dragged (fn [self] 
+          (. backlight (set-brightness (.get-value self)))))])))