devilspie2: add module (#1477)

Co-authored-by: Sumner Evans <me@sumnerevans.com>
Co-authored-by: Nicolas Berbiche <nicolas@normie.dev>

modules/modules.nix

@@ -159,6 +159,7 @@ let
     (loadModule ./services/cbatticon.nix { condition = hostPlatform.isLinux; })
     (loadModule ./services/clipmenu.nix { condition = hostPlatform.isLinux; })
     (loadModule ./services/compton.nix { })
+    (loadModule ./services/devilspie2.nix { condition = hostPlatform.isLinux; })
     (loadModule ./services/dropbox.nix { condition = hostPlatform.isLinux; })
     (loadModule ./services/dunst.nix { })
     (loadModule ./services/dwm-status.nix { condition = hostPlatform.isLinux; })

modules/services/devilspie2.nix

@@ -0,0 +1,42 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+let cfg = config.services.devilspie2;
+in {
+  meta.maintainers = [ maintainers.dawidsowa ];
+
+  options = {
+    services.devilspie2 = {
+      enable = mkEnableOption ''
+        Devilspie2, a window matching utility, allowing the user to
+        perform scripted actions on windows as they are created'';
+
+      config = mkOption {
+        type = types.lines;
+        default = "";
+        description = ''
+          Content of file placed in the devilspie2 config directory.
+        '';
+        example = ''
+          if (get_window_class() == "Gnome-terminal") then
+              make_always_on_top();
+          end
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.user.services.devilspie2 = {
+      Service.ExecStart = "${pkgs.devilspie2}/bin/devilspie2";
+      Unit = {
+        Description = "devilspie2";
+        After = [ "graphical-session-pre.target" ];
+        PartOf = [ "graphical-session.target" ];
+      };
+      Install.WantedBy = [ "graphical-session.target" ];
+    };
+
+    xdg.configFile."devilspie2/config.lua".text = cfg.config;
+  };
+}