l 3 power-action: add charging check

lass/3modules/power-action.nix

@@ -25,6 +25,16 @@ let
     plans = mkOption {
       type = with types; attrsOf (submodule {
         options = {
+          charging = mkOption {
+            type = nullOr bool;
+            default = null;
+            description = ''
+              check for charging status.
+              null = don't care
+              true = only if system is charging
+              false = only if system is discharging
+            '';
+          };
           upperLimit = mkOption {
             type = int;
           };
@@ -53,15 +63,31 @@ let
   };
 
   startScript = pkgs.writeDash "power-action" ''
+    set -euf
+
     power="$(${powerlvl})"
+    state="$(${state})"
     ${concatStringsSep "\n" (mapAttrsToList writeRule cfg.plans)}
   '';
+  charging_check = plan:
+    if (plan.charging == null) then "" else
+      if plan.charging
+        then ''&& [ "$state" = "true" ]''
+        else ''&& ! [ "$state" = "true" ]''
+    ;
 
   writeRule = _: plan:
-    "if [ $power -ge ${toString plan.lowerLimit} ] && [ $power -le ${toString plan.upperLimit} ]; then ${plan.action}; fi";
+    "if [ $power -ge ${toString plan.lowerLimit} ] && [ $power -le ${toString plan.upperLimit} ] ${charging_check plan}; then ${plan.action}; fi";
 
   powerlvl = pkgs.writeDash "powerlvl" ''
     cat /sys/class/power_supply/BAT0/capacity
   '';
 
+  state = pkgs.writeDash "state" ''
+    if [ "$(cat /sys/class/power_supply/BAT0/status)" = "Charging" ]
+      then echo "true"
+      else echo "false"
+    fi
+  '';
+
 in out