[i3+sway] Setup brightness controll for ddc monitors

home/roles/i3+sway/default.nix

@@ -343,7 +343,7 @@ in {
 
           modules-left = [ "sway/workspaces" "sway/mode" ];
           modules-center = [ ];
-          modules-right = [ "disk" "cpu" "memory" "pulseaudio" "backlight" "network" "battery" "tray" "clock" ];
+          modules-right = [ "disk" "cpu" "memory" "pulseaudio" "custom/backlight-ddc" "backlight" "network" "battery" "tray" "clock" ];
 
           "sway/workspaces" = {
             disable-scroll = true;
@@ -400,6 +400,23 @@ in {
             tooltip = false;
           };
 
+          "custom/backlight-ddc" = {
+            exec = pkgs.writeShellScript "waybar-backlight-ddc" ''
+              if command -v ddcutil &>/dev/null; then
+                # Display current brightness
+                brightness=$(ddcutil getvcp 10 --brief 2>/dev/null | awk '{print $4}')
+                if [ -n "$brightness" ]; then
+                  echo "☀️ $brightness%"
+                fi
+              fi
+            '';
+            interval = 5;
+            format = "{}";
+            on-scroll-up = "ddcutil setvcp 10 + 5 2>/dev/null &";
+            on-scroll-down = "ddcutil setvcp 10 - 5 2>/dev/null &";
+            tooltip = false;
+          };
+
           "network" = {
             format-wifi = "📶 {essid} ({signalStrength}%)";
             format-ethernet = "🔌 {ipaddr}";

roles/users/default.nix

@@ -25,7 +25,7 @@ in
     users.users.johno = {
       isNormalUser = true;
       description = "John Ogle";
-      extraGroups = [ "wheel" "networkmanager" "audio" "video" ] ++ cfg.extraGroups;
+      extraGroups = [ "wheel" "networkmanager" "audio" "video" "i2c" ] ++ cfg.extraGroups;
     };
 
     users.users.eli = mkIf cfg.kids {