style waybar, add mpd module, other fixes

lib/modules/mpd.nix

@@ -0,0 +1,32 @@
+{ user }: { lib, pkgs, config, ... }:
+with lib;
+let
+  cfg = config.roles.mpd;
+in
+{
+  options.roles.mpd = {
+    enable = mkEnableOption "setup mpd client";
+    host = mkOption {default = "music.local";};
+  };
+
+  config = mkIf cfg.enable {
+    home-manager.users.${user}.imports = [{
+      programs.ncmpcpp = {
+        enable = true;
+        settings.mpd_host = cfg.host;
+        bindings = [
+          { key = "j"; command = "scroll_down"; }
+          { key = "k"; command = "scroll_up"; }
+          { key = "l"; command = "next_column"; }
+          { key = "h"; command = "previous_column"; }
+          { key = "J"; command = [ "select_item" "scroll_down" ]; }
+          { key = "K"; command = [ "select_item" "scroll_up" ]; }
+        ];
+      };
+      services.mpd-mpris = {
+        enable = true;
+        mpd.host = cfg.host;
+      };
+    }];
+  };
+}