From https://once.com/writebook

app/helpers/arrangement_helper.rb

@@ -0,0 +1,38 @@
+module ArrangementHelper
+  def arrangement_tag(book, **, &)
+    tag.div data: {
+      controller: "arrangement reading-progress",
+      arrangement_cursor_class: "arrangement-cursor",
+      arrangement_selected_class: "arrangement-selected",
+      arrangement_placeholder_class: "arrangement-placeholder",
+      arrangement_adding_mode_class: "arrangement--adding",
+      arrangement_move_mode_class: "arrangement-move-mode",
+      arrangement_url_value: book_leaves_moves_url(book),
+      reading_progress_book_id_value: book.id,
+      reading_progress_last_read_class: "toc__leaf--last-read"
+    }, **, &
+  end
+
+  def arrangement_actions
+    actions = {
+      "click": "click",
+      "dragstart": "dragStart",
+      "dragover": "dragOver:prevent",
+      "dragend": "dragEnd",
+      "drop": "drop",
+      "keydown.up": "moveBefore",
+      "keydown.right": "moveAfter",
+      "keydown.down": "moveAfter",
+      "keydown.left": "moveBefore",
+      "keydown.shift+up": "moveBefore",
+      "keydown.shift+right": "moveAfter",
+      "keydown.shift+down": "moveAfter",
+      "keydown.shift+left": "moveBefore",
+      "keydown.space": "toggleMoveMode",
+      "keydown.enter": "applyMoveMode",
+      "keydown.esc": "cancelMoveMode"
+    }
+
+    actions.map { |action, target| "#{action}->arrangement##{target}" }.join(" ")
+  end
+end