group module: configurable orientation

currently, the orientation of group modules is always the opposite of
the bar. Change it so that:

* the default orientation of the group module is always the opposite of
  its parent, even for nested groups
* the orientation can be overridden in the config
* css ID and class are set for the group element

include/group.hpp

@@ -12,7 +12,7 @@ namespace waybar {
 
 class Group : public AModule {
  public:
-  Group(const std::string&, const Bar&, const Json::Value&);
+  Group(const std::string&, const std::string&, const Json::Value&, bool);
   ~Group() = default;
   auto update() -> void;
   operator Gtk::Widget&();

man/waybar.5.scd.in

@@ -242,6 +242,7 @@ A module group is defined by specifying a module named "group/some-group-name".
 	"modules-right": ["group/hardware", "clock"],
 
 	"group/hardware": {
+		"orientation": "vertical",
 		"modules": [
 			"cpu",
 			"memory",
@@ -253,6 +254,8 @@ A module group is defined by specifying a module named "group/some-group-name".
 }
 ```
 
+Valid options for the (optional) "orientation" property are: "horizontal", "vertical", "inherit", and "orthogonal" (default).
+
 # SUPPORTED MODULES
 
 - *waybar-backlight(5)*

src/bar.cpp

@@ -742,7 +742,13 @@ void waybar::Bar::getModules(const Factory& factory, const std::string& pos,
         AModule* module;
 
         if (ref.compare(0, 6, "group/") == 0 && ref.size() > 6) {
-          auto group_module = new waybar::Group(ref, *this, config[ref]);
+          auto hash_pos = ref.find('#');
+          auto id_name = ref.substr(6, hash_pos - 6);
+          auto class_name = hash_pos != std::string::npos ? ref.substr(hash_pos + 1) : "";
+
+          auto parent = group ? group : &this->box_;
+          auto vertical = parent->get_orientation() == Gtk::ORIENTATION_VERTICAL;
+          auto group_module = new waybar::Group(id_name, class_name, config[ref], vertical);
           getModules(factory, ref, &group_module->box);
           module = group_module;
         } else {
@@ -764,11 +770,11 @@ void waybar::Bar::getModules(const Factory& factory, const std::string& pos,
             modules_right_.emplace_back(module_sp);
           }
         }
-        module->dp.connect([module, name] {
+        module->dp.connect([module, ref] {
           try {
             module->update();
           } catch (const std::exception& e) {
-            spdlog::error("{}: {}", name.asString(), e.what());
+            spdlog::error("{}: {}", ref, e.what());
           }
         });
       } catch (const std::exception& e) {

src/group.cpp

@@ -6,9 +6,30 @@
 
 namespace waybar {
 
-Group::Group(const std::string& name, const Bar& bar, const Json::Value& config)
+Group::Group(const std::string& name, const std::string& id, const Json::Value& config,
-    : AModule(config, name, "", false, false),
+             bool vertical)
-      box{bar.vertical ? Gtk::ORIENTATION_HORIZONTAL : Gtk::ORIENTATION_VERTICAL, 0} {}
+    : AModule(config, name, id, false, false),
+      box{vertical ? Gtk::ORIENTATION_VERTICAL : Gtk::ORIENTATION_HORIZONTAL, 0} {
+  box.set_name(name_);
+  if (!id.empty()) {
+    box.get_style_context()->add_class(id);
+  }
+
+  // default orientation: orthogonal to parent
+  auto orientation =
+      config_["orientation"].empty() ? "orthogonal" : config_["orientation"].asString();
+  if (orientation == "inherit") {
+    // keep orientation passed
+  } else if (orientation == "orthogonal") {
+    box.set_orientation(vertical ? Gtk::ORIENTATION_HORIZONTAL : Gtk::ORIENTATION_VERTICAL);
+  } else if (orientation == "vertical") {
+    box.set_orientation(Gtk::ORIENTATION_VERTICAL);
+  } else if (orientation == "horizontal") {
+    box.set_orientation(Gtk::ORIENTATION_HORIZONTAL);
+  } else {
+    throw std::runtime_error("Invalid orientation value: " + orientation);
+  }
+}
 
 auto Group::update() -> void {
   // noop