Include self and ancestors in result

app/assets/stylesheets/application.css

@@ -379,7 +379,8 @@ table.items td {
 }
 /* For <a> to fill <td> completely, we use an ::after pseudoelement. */
 table.items td.link {
-  padding: 0 0 0 1em;
+  padding: 0;
+  padding-inline-start: calc(1em + var(--depth) * 0.8em);
   position: relative;
 }
 table.items td.link a {

app/models/quantity.rb

@@ -12,38 +12,33 @@ class Quantity < ApplicationRecord
 
   scope :defaults, ->{ where(user: nil) }
   scope :ordered, ->{
-    cte = Arel::Table.new('cte')
     numbered = Arel::Table.new('numbered')
-    Quantity.with(numbered: numbered(:parent_id, :name)).with_recursive(
-      cte:
-      [
-        Arel::SelectManager.new.project(
-          numbered[Arel.star],
-          numbered.cast(numbered[:child_number], 'BINARY').as('path')
-        ).from(numbered).where(numbered[:parent_id].eq(nil)),
-        Arel::SelectManager.new.project(
-          numbered[Arel.star],
-          cte[:path].concat(numbered[:child_number])
-        ).from(numbered).join(cte).on(numbered[:parent_id].eq(cte[:id]))
-      ]
-    ).select(cte[Arel.star]).from(cte).order(cte[:path])
+    Quantity.with(numbered: numbered(:parent_id, :name)).with_recursive(quantities: [
+      Arel::SelectManager.new.project(
+        numbered[Arel.star],
+        numbered.cast(numbered[:child_number], 'BINARY').as('path'),
+        Arel::Nodes.build_quoted(0).as('depth')
+      ).from(numbered).where(numbered[:parent_id].eq(nil)),
+      Arel::SelectManager.new.project(
+        numbered[Arel.star],
+        arel_table[:path].concat(numbered[:child_number]),
+        arel_table[:depth] + 1
+      ).from(numbered).join(arel_table).on(numbered[:parent_id].eq(arel_table[:id]))
+    ]).select(arel_table[Arel.star]).from(arel_table).order(arel_table[:path])
   }
 
+  # TODO: extract named functions to custom Arel extension
+  # https://gist.github.com/ProGM/c6df08da14708dcc28b5ca325df37ceb#extending-arel
   scope :numbered, ->(parent_column, order_column){
     select(
       arel_table[Arel.star],
       Arel::Nodes::NamedFunction.new(
         'LPAD',
         [
-          Arel::Nodes::NamedFunction.new(
-            'ROW_NUMBER', []
-          ).over(
-            Arel::Nodes::Window.new.partition(parent_column).order(order_column)
-          ),
+          Arel::Nodes::NamedFunction.new('ROW_NUMBER', [])
+            .over(Arel::Nodes::Window.new.partition(parent_column).order(order_column)),
           Arel::SelectManager.new.project(
-            Arel::Nodes::NamedFunction.new(
-              'LENGTH', [Arel::Nodes::NamedFunction.new('COUNT', [Arel.star])]
-            )
+            Arel::Nodes::NamedFunction.new('LENGTH', [Arel.star.count])])
           ),
           Arel::Nodes.build_quoted('0')
         ],
@@ -62,4 +57,24 @@ class Quantity < ApplicationRecord
   def default?
     parent_id.nil?
   end
+
+  # Return: record, its ancestors and succesive record in order of appearance,
+  # including :depth attribute. Used for table view reload.
+  def successive
+    quantities = Quantity.arel_table
+    ancestors = Arel::Table.new('ancestors')
+    Quantity.with(
+      ancestors: user.quantities.ordered.select(
+        Arel::Nodes::NamedFunction.new('LAG', [quantities[:id]]).over.as('lag_id')
+      )
+    )
+    .with_recursive(quantities: [
+      Arel::SelectManager.new.project(ancestors[Arel.star]).from(ancestors)
+        .where(ancestors[:id].eq(id).or(ancestors[:lag_id].eq(id))),
+      Arel::SelectManager.new.project(ancestors[Arel.star]).from(ancestors)
+        .join(quantities).on(quantities[:parent_id].eq(ancestors[:id]))
+        .where(quantities[:lag_id].not_eq(id))
+    ]).order(quantities[:path])
+    # return: .first == self ? nul, ancestors : ancestors.pop, ancestors
+  end
 end

app/views/units/_form.html.erb

@@ -10,7 +10,6 @@
     </td>
     <td class="number">
       <% unless @unit.base.nil? %>
-        <%= form.hidden_field :base_id %>
         <%= form.number_field :multiplier, required: true, size: 10, min: :step %>
       <% end %>
     </td>

app/views/units/new.turbo_stream.erb

@@ -7,7 +7,8 @@
 <%= turbo_stream.disable ids[:link] -%>
 
 <%= turbo_stream.append :unit_form do %>
-  <%- tabular_form_with model: @unit, html: {id: ids[:form_tag]} do %>
+  <%- tabular_form_with model: @unit, html: {id: ids[:form_tag]} do |form| %>
+    <%= form.hidden_field :base_id unless @unit.base.nil? %>
   <% end %>
 <% end %>