dwm: Add layout scroll; rename settings

Rename settings and allow more flexible configuration by allowing the user to
enable click handlers for the tags and the layout label separately.

Add a scroll handler for the layout label so the user can scroll through the
available layouts. Enabling layout-scroll-wrap allows wrapping back to the
beginning/end of the array of available layouts.

next_layout and prev_layout take the address of a layout and returns the
next/previous layout in the m_layouts array if possible, wrapping if specified,
otherwise returns the same layout. This is used to for the layout scroll
handlers to cycle through layouts.

config.cmake

@@ -168,11 +168,14 @@ label-urgent-padding = 2
 
 [module/dwm]
 type = internal/dwm
-format = <label-tags> <label-layout>> <label-title>
+format = <label-tags> <label-layout> <label-title>
 
-enable-click = false
+enable-tags-click = false
+enable-layout-click = false
+enable-layout-scroll = false
+layout-scroll-wrap = false
 
-; If enable-click = true, clicking the layout symbol will switch to this layout
+; If enable-layout-click = true, clicking the layout symbol will switch to this layout
 secondary-layout-symbol = [M]
 
 ; State

include/modules/dwm.hpp

@@ -105,6 +105,18 @@ namespace modules {
      */
     static constexpr const char* EVENT_LAYOUT_RCLICK{"setlayoutsafe"};
 
+    /**
+     * Event name is same as the IPC command name to set the layout to the
+     * previous layout in the array.
+     */
+    static constexpr const char* EVENT_LAYOUT_SDOWN{"setlayoutsafe"};
+
+    /**
+     * Event name is same as the IPC command name to set the layout to the
+     * next layout in the array.
+     */
+    static constexpr const char* EVENT_LAYOUT_SUP{"setlayoutsafe"};
+
     /**
      * Called by has_event on layout changes. This updates the layout label
      *
@@ -182,6 +194,24 @@ namespace modules {
      */
     auto find_layout(uintptr_t addr) const -> const dwmipc::Layout*;
 
+    /**
+     * Get the address of the next layout in m_layouts.
+     *
+     * @param layout Address of the current layout
+     * @param wrap True to wrap around the array, false to return the same
+     *   layout if the next layout does not exist.
+     */
+    auto next_layout(const dwmipc::Layout& layout, bool wrap) const -> const dwmipc::Layout*;
+
+    /**
+     * Get the address of the previous layout in m_layouts.
+     *
+     * @param layout Address of the current layout
+     * @param wrap True to wrap around the array, false to return the same
+     *   layout if the next layout does not exist.
+     */
+    auto prev_layout(const dwmipc::Layout& layout, bool wrap) const -> const dwmipc::Layout*;
+
     /**
      * Check if the command matches the specified event name and if so, send a
      * command to dwm after parsing the command.
@@ -211,7 +241,22 @@ namespace modules {
     /**
      * If true, enables the click handlers for the tags
      */
-    bool m_click{true};
+    bool m_tags_click{true};
+
+    /**
+     * If true, enables the click handlers for the layout label
+     */
+    bool m_layout_click{true};
+
+    /**
+     * If true, scrolling the layout cycle through available layouts
+     */
+    bool m_layout_scroll{true};
+
+    /**
+     * If true, scrolling the layout will wrap around to the beginning
+     */
+    bool m_layout_wrap{true};
 
     /**
      * If the layout symbol is clicked on, it will set the layout represented by

src/modules/dwm.cpp

@@ -28,8 +28,7 @@ namespace modules {
     m_ipc = factory_util::unique<dwmipc::Connection>(socket_path);
 
     // Load configuration
-    m_formatter->add(
+    m_formatter->add(DEFAULT_FORMAT, DEFAULT_FORMAT_TAGS, {TAG_LABEL_TAGS, TAG_LABEL_LAYOUT, TAG_LABEL_TITLE});
-        DEFAULT_FORMAT, DEFAULT_FORMAT_TAGS, {TAG_LABEL_TAGS, TAG_LABEL_LAYOUT, TAG_LABEL_TITLE});
 
     // Populate m_state_labels map with labels and their states
     if (m_formatter->has(TAG_LABEL_TAGS)) {
@@ -55,8 +54,10 @@ namespace modules {
       m_title_label = load_optional_label(m_conf, name(), "label-title", "%title%");
     }
 
-    m_click = m_conf.get(name(), "enable-click", m_click);
+    m_tags_click = m_conf.get(name(), "enable-tags-click", m_tags_click);
-
+    m_layout_click = m_conf.get(name(), "enable-layout-click", m_layout_click);
+    m_layout_scroll = m_conf.get(name(), "enable-layout-scroll", m_layout_scroll);
+    m_layout_wrap = m_conf.get(name(), "layout-scroll-wrap", m_layout_wrap);
     m_secondary_layout_symbol = m_conf.get(name(), "secondary-layout-symbol", m_secondary_layout_symbol);
 
     try {
@@ -153,17 +154,27 @@ namespace modules {
     if (tag == TAG_LABEL_TITLE) {
       builder->node(m_title_label);
     } else if (tag == TAG_LABEL_LAYOUT) {
-      if (m_click) {
+      if (m_layout_click) {
         // Toggle between secondary and default layout
         auto addr = (m_current_layout == m_default_layout ? m_secondary_layout : m_default_layout)->address;
         builder->cmd(mousebtn::LEFT, build_cmd(EVENT_LAYOUT_LCLICK, to_string(addr)));
         // Set previous layout
         builder->cmd(mousebtn::RIGHT, build_cmd(EVENT_LAYOUT_RCLICK, "0"));
-        builder->node(m_layout_label);
+      }
+      if (m_layout_scroll) {
+        auto addr_next = next_layout(*m_current_layout, m_layout_wrap)->address;
+        auto addr_prev = prev_layout(*m_current_layout, m_layout_wrap)->address;
+        builder->cmd(mousebtn::SCROLL_DOWN, build_cmd(EVENT_LAYOUT_SDOWN, to_string(addr_prev)));
+        builder->cmd(mousebtn::SCROLL_UP, build_cmd(EVENT_LAYOUT_SUP, to_string(addr_next)));
+      }
+      builder->node(m_layout_label);
+      if (m_layout_click) {
+        builder->cmd_close();
+        builder->cmd_close();
+      }
+      if (m_layout_scroll) {
         builder->cmd_close();
         builder->cmd_close();
-      } else {
-        builder->node(m_layout_label);
       }
     } else if (tag == TAG_LABEL_TAGS) {
       bool first = true;
@@ -175,7 +186,7 @@ namespace modules {
           builder->node(m_seperator_label);
         }
 
-        if (m_click) {
+        if (m_tags_click) {
           builder->cmd(mousebtn::LEFT, build_cmd(EVENT_TAG_LCLICK, to_string(tag.bit_mask)));
           builder->cmd(mousebtn::RIGHT, build_cmd(EVENT_TAG_RCLICK, to_string(tag.bit_mask)));
           builder->node(tag.label);
@@ -220,7 +231,8 @@ namespace modules {
     }
 
     return check_send_cmd(cmd, EVENT_TAG_LCLICK) || check_send_cmd(cmd, EVENT_TAG_RCLICK) ||
-           check_send_cmd(cmd, EVENT_LAYOUT_LCLICK) || check_send_cmd(cmd, EVENT_LAYOUT_RCLICK);
+           check_send_cmd(cmd, EVENT_LAYOUT_LCLICK) || check_send_cmd(cmd, EVENT_LAYOUT_RCLICK) ||
+           check_send_cmd(cmd, EVENT_LAYOUT_SDOWN) || check_send_cmd(cmd, EVENT_LAYOUT_SUP);
   }
 
   auto dwm_module::get_state(tag_mask_t bit_mask) const -> state_t {
@@ -289,6 +301,30 @@ namespace modules {
     return nullptr;
   }
 
+  auto dwm_module::next_layout(const dwmipc::Layout& layout, bool wrap) const -> const dwmipc::Layout* {
+    const auto* next = &layout + 1;
+    const auto* first = m_layouts->begin().base();
+    if (next < m_layouts->end().base()) {
+      return next;
+    } else if (wrap) {
+      return first;
+    } else {
+      return &layout;
+    }
+  }
+
+  auto dwm_module::prev_layout(const dwmipc::Layout& layout, bool wrap) const -> const dwmipc::Layout* {
+    const auto* prev = &layout - 1;
+    const auto* last = m_layouts->end().base() - 1;
+    if (prev >= m_layouts->begin().base()) {
+      return prev;
+    } else if (wrap) {
+      return last;
+    } else {
+      return &layout;
+    }
+  }
+
   void dwm_module::update_tag_labels() {
     for (auto& t : m_tags) {
       t.state = get_state(t.bit_mask);