dwm: Add label-floating

This label is visible when the currently focused client is in floating mode and
detached from the layout. It uses the focused_state_change_event as well as the
focused_client_change_event to check if the focused client is floating and
updates m_is_floating accordingly which will enable/disbale the floating label
in the final output.

update_floating_label is called when the floating state of the client is not
known. The function queries dwm for the properties of the focused client and
sets m_is_floating accordingly.

This fixes issue #2.

config.cmake

@@ -168,7 +168,7 @@ label-urgent-padding = 2
 
 [module/dwm]
 type = internal/dwm
-format = <label-tags> <label-layout> <label-title>
+format = <label-tags> <label-layout> <label-floating> <label-title>
 
 enable-tags-click = false
 enable-layout-click = false

include/modules/dwm.hpp

@@ -56,7 +56,7 @@ namespace modules {
     auto input(string&& cmd) -> bool override;
 
    private:
-    static constexpr const char* DEFAULT_FORMAT_TAGS{"<label-tags> <label-layout> <label-title>"};
+    static constexpr const char* DEFAULT_FORMAT_TAGS{"<label-tags> <label-layout> <label-floating> <label-title>"};
     static constexpr const char* DEFAULT_STATE_LABEL{"%name%"};
 
     /**
@@ -75,6 +75,11 @@ namespace modules {
      */
     static constexpr const char* TAG_LABEL_LAYOUT{"<label-layout>"};
 
+    /**
+     * The floating label is shown when the selected window is floating
+     */
+    static constexpr const char* TAG_LABEL_FLOATING{"<label-floating>"};
+
     /**
      * The title layout is replaced by the currently focused window title
      */
@@ -140,6 +145,14 @@ namespace modules {
      */
     void on_focused_title_change(const dwmipc::FocusedTitleChangeEvent& ev);
 
+    /**
+     * Called by has_event when the state of the currently focused window
+     * changes. This updates the floating label.
+     *
+     * @param ev Event data
+     */
+    void on_focused_state_change(const dwmipc::FocusedStateChangeEvent& ev);
+
     /**
      * Get a list of monitors from dwm, store them in m_monitors, and update the
      * pointers to the active monitor and bar monitor.
@@ -159,6 +172,12 @@ namespace modules {
      */
     void update_title_label();
 
+    /**
+     * Query dwm to determine if the currently focused client and update
+     * m_is_floating
+     */
+    void update_floating_label();
+
     /**
      * Translate the tag's tag states to a state_t enum value
      *
@@ -246,6 +265,11 @@ namespace modules {
      */
     bool m_layout_reverse{false};
 
+    /**
+     * If true, show floating label
+     */
+    bool m_is_floating{false};
+
     /**
      * If the layout symbol is clicked on, it will set the layout represented by
      * this symbol. The default is monocle mode [M].
@@ -288,6 +312,11 @@ namespace modules {
      */
     label_t m_layout_label;
 
+    /**
+     * Shown when currently focused window is floating
+     */
+    label_t m_floating_label;
+
     /**
      * Inserted between tags
      */

src/modules/dwm.cpp

@@ -28,7 +28,7 @@ namespace modules {
     m_ipc = factory_util::unique<dwmipc::Connection>(socket_path);
 
     // Load configuration
-    m_formatter->add(DEFAULT_FORMAT, DEFAULT_FORMAT_TAGS, {TAG_LABEL_TAGS, TAG_LABEL_LAYOUT, TAG_LABEL_TITLE});
+    m_formatter->add(DEFAULT_FORMAT, DEFAULT_FORMAT_TAGS, {TAG_LABEL_TAGS, TAG_LABEL_LAYOUT, TAG_LABEL_FLOATING, TAG_LABEL_TITLE});
 
     // Populate m_state_labels map with labels and their states
     if (m_formatter->has(TAG_LABEL_TAGS)) {
@@ -50,6 +50,10 @@ namespace modules {
       m_layout_label = load_optional_label(m_conf, name(), "label-layout", "%layout%");
     }
 
+    if (m_formatter->has(TAG_LABEL_FLOATING)) {
+      m_floating_label = load_optional_label(m_conf, name(), "label-floating", "");
+    }
+
     if (m_formatter->has(TAG_LABEL_TITLE)) {
       m_title_label = load_optional_label(m_conf, name(), "label-title", "%title%");
     }
@@ -74,6 +78,10 @@ namespace modules {
         m_tags.emplace_back(t.tag_name, t.bit_mask, state, move(label));
       }
 
+      if (m_floating_label) {
+        update_floating_label();
+      }
+
       if (m_layout_label) {
         auto layouts = m_ipc->get_layouts();
         m_layouts = m_ipc->get_layouts();
@@ -106,6 +114,14 @@ namespace modules {
         m_ipc->subscribe(dwmipc::Event::FOCUSED_TITLE_CHANGE);
       }
 
+      if (m_floating_label) {
+        update_floating_label();
+        m_ipc->on_focused_state_change = [this](const dwmipc::FocusedStateChangeEvent& ev) {
+          this->on_focused_state_change(ev);
+        };
+        m_ipc->subscribe(dwmipc::Event::FOCUSED_STATE_CHANGE);
+      }
+
       // This event is for keeping track of the currently focused monitor
       m_ipc->on_monitor_focus_change = [this](const dwmipc::MonitorFocusChangeEvent& ev) {
         this->on_monitor_focus_change(ev);
@@ -154,6 +170,11 @@ namespace modules {
   auto dwm_module::build(builder* builder, const string& tag) const -> bool {
     if (tag == TAG_LABEL_TITLE) {
       builder->node(m_title_label);
+    } else if (tag == TAG_LABEL_FLOATING) {
+      if (!m_is_floating) {
+        return true;
+      }
+      builder->node(m_floating_label);
     } else if (tag == TAG_LABEL_LAYOUT) {
       if (m_layout_click) {
         // Toggle between secondary and default layout
@@ -353,6 +374,21 @@ namespace modules {
     m_title_label->replace_token("%title%", new_title);
   }
 
+  void dwm_module::update_floating_label() {
+    if (m_focused_client_id != 0) {
+      try {
+        m_is_floating = m_ipc->get_client(m_focused_client_id)->states.is_floating;
+      } catch (const dwmipc::SocketClosedError& err) {
+        m_log.err("%s: Disconnected from socket: %s", name(), err.what());
+        reconnect_dwm();
+      } catch (const dwmipc::IPCError& err) {
+        throw module_error(err.what());
+      }
+    } else {
+      m_is_floating = false;
+    }
+  }
+
   auto dwm_module::reconnect_dwm() -> bool {
     try {
       if (!m_ipc->is_main_socket_connected()) {
@@ -401,10 +437,17 @@ namespace modules {
     }
   }
 
+  void dwm_module::on_focused_state_change(const dwmipc::FocusedStateChangeEvent& ev) {
+    if (ev.monitor_num == m_bar_mon->num && ev.client_window_id == m_focused_client_id) {
+      m_is_floating = ev.new_state.is_floating;
+    }
+  }
+
   void dwm_module::on_client_focus_change(const dwmipc::ClientFocusChangeEvent& ev) {
     if (ev.monitor_num == m_bar_mon->num) {
       m_focused_client_id = ev.new_win_id;
       update_title_label();
+      update_floating_label();
     }
   }