feat: independence from stockholm

modules/power-action.nix

@@ -0,0 +1,94 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; let
+  cfg = config.services.power-action;
+
+  out = {
+    options.services.power-action = api;
+    config = lib.mkIf cfg.enable imp;
+  };
+
+  api = {
+    enable = mkEnableOption "power-action";
+    battery = mkOption {
+      type = types.str;
+      default = "BAT0";
+    };
+    user = mkOption {
+      type = types.str;
+      default = "power-action";
+    };
+    startAt = mkOption {
+      type = types.str;
+      default = "*:0/1";
+    };
+    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 or unknown
+                false = only if system is discharging
+              '';
+            };
+            upperLimit = mkOption {
+              type = int;
+            };
+            lowerLimit = mkOption {
+              type = int;
+            };
+            action = mkOption {
+              type = path;
+            };
+          };
+        });
+    };
+  };
+
+  imp = {
+    systemd.services.power-action = {
+      serviceConfig = rec {
+        ExecStart = startScript;
+        User = cfg.user;
+      };
+      startAt = cfg.startAt;
+    };
+  };
+
+  startScript = pkgs.writers.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} ] ${charging_check plan}; then ${plan.action}; fi";
+
+  powerlvl = pkgs.writers.writeDash "powerlvl" ''
+    cat /sys/class/power_supply/${cfg.battery}/capacity
+  '';
+
+  state = pkgs.writers.writeDash "state" ''
+    if [ "$(cat /sys/class/power_supply/${cfg.battery}/status)" = "Discharging" ]
+      then echo "false"
+      else echo "true"
+    fi
+  '';
+in
+  out