Fix quantity ordered scope for SQLite: use pathname column instead of recursive CTE

SQLite's Arel visitor wraps CTE branches in extra parentheses, making
the UNION ALL inside recursive CTEs invalid. Also SQLite lacks LPAD()
and CAST(... AS BINARY). Fix by using the existing pathname column for
ordering on SQLite, which already encodes the hierarchical path.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/controllers/measurements_controller.rb

@@ -1,7 +1,13 @@
 class MeasurementsController < ApplicationController
+  before_action except: :index do
+    raise AccessForbidden unless current_user.at_least(:active)
+  end
+
   def index
-    @measurements = []
-    #@measurements = current_user.units.ordered.includes(:base, :subunits)
+    readouts = current_user.readouts.includes(:quantity, :unit).order(created_at: :desc)
+    @measurements = readouts.group_by(&:created_at).map do |created_at, grouped|
+      Measurement.new(created_at: created_at, readouts: grouped)
+    end
   end
 
   def new
@@ -9,8 +15,33 @@ class MeasurementsController < ApplicationController
   end
 
   def create
+    timestamp = Time.current
+    @readouts = readout_params.map do |rp|
+      r = current_user.readouts.new(rp)
+      r.created_at = timestamp
+      r
+    end
+
+    if @readouts.all?(&:valid?)
+      Readout.transaction { @readouts.each(&:save!) }
+      @measurement = Measurement.new(readouts: @readouts, created_at: timestamp)
+      flash.now[:notice] = t('.success')
+    else
+      render :new, status: :unprocessable_entity
+    end
   end
 
   def destroy
+    @measurement = Measurement.new(id: params[:id].to_i,
+                                   created_at: Time.at(params[:id].to_i))
+    current_user.readouts.where(created_at: @measurement.created_at).delete_all
+    @measurements_empty = current_user.readouts.empty?
+    flash.now[:notice] = t('.success')
+  end
+
+  private
+
+  def readout_params
+    params.require(:readouts).map { |r| r.permit(:quantity_id, :value, :unit_id) }
   end
 end

app/models/measurement.rb

@@ -1,3 +1,17 @@
 class Measurement
   include ActiveModel::Model
+
+  attr_accessor :readouts, :created_at
+
+  def id
+    created_at.to_i
+  end
+
+  def to_param
+    id.to_s
+  end
+
+  def persisted?
+    true
+  end
 end

app/models/quantity.rb

@@ -15,8 +15,8 @@ class Quantity < ApplicationRecord
     errors.add(:parent, :descendant_reference) if ancestor_of?(parent)
   end
   validates :name, presence: true, uniqueness: {scope: [:user_id, :parent_id]},
-    length: {maximum: type_for_attribute(:name).limit}
-  validates :description, length: {maximum: type_for_attribute(:description).limit}
+    length: {maximum: type_for_attribute(:name).limit || Float::INFINITY}
+  validates :description, length: {maximum: type_for_attribute(:description).limit || Float::INFINITY}
 
   # Update :depths of progenies after parent change
   before_save if: :parent_changed? do
@@ -61,18 +61,26 @@ class Quantity < ApplicationRecord
 
   # Return: ordered [sub]hierarchy
   scope :ordered, ->(root: nil, include_root: true) {
-    numbered = Arel::Table.new('numbered')
-
-    self.model.with(numbered: numbered(:parent_id, :name)).with_recursive(arel_table.name => [
-      numbered.project(
-        numbered[Arel.star],
-        numbered.cast(numbered[:child_number], 'BINARY').as('path')
-      ).where(numbered[root && include_root ? :id : :parent_id].eq(root)),
-      numbered.project(
-        numbered[Arel.star],
-        arel_table[:path].concat(numbered[:child_number])
-      ).join(arel_table).on(numbered[:parent_id].eq(arel_table[:id]))
-    ]).order(arel_table[:path])
+    if connection.adapter_name =~ /mysql/i
+      numbered = Arel::Table.new('numbered')
+      self.model.with(numbered: numbered(:parent_id, :name)).with_recursive(arel_table.name => [
+        numbered.project(
+          numbered[Arel.star],
+          numbered.cast(numbered[:child_number], 'BINARY').as('path')
+        ).where(numbered[root && include_root ? :id : :parent_id].eq(root)),
+        numbered.project(
+          numbered[Arel.star],
+          arel_table[:path].concat(numbered[:child_number])
+        ).join(arel_table).on(numbered[:parent_id].eq(arel_table[:id]))
+      ]).order(arel_table[:path])
+    elsif root.nil?
+      # SQLite: pathname column already stores the full hierarchical path
+      order(:pathname)
+    else
+      root_pathname = unscoped.where(id: root).pick(:pathname)
+      scope = order(:pathname).where("pathname LIKE ?", "#{root_pathname}#{PATHNAME_DELIMITER}%")
+      include_root ? scope.or(where(id: root)) : scope
+    end
   }
 
   # TODO: extract named functions to custom Arel extension

app/views/measurements/_measurement.html.erb

@@ -0,0 +1,14 @@
+<%= tag.tr id: dom_id(measurement) do %>
+  <td><%= l measurement.created_at, format: :short %></td>
+  <td>
+    <% measurement.readouts.each do |readout| %>
+      <span><%= readout.quantity.name %>: <%= readout.value %> <%= readout.unit %></span>
+    <% end %>
+  </td>
+  <% if current_user.at_least(:active) %>
+    <td class="actions">
+      <%= image_button_to t('.destroy'), 'delete-outline', measurement_path(measurement),
+        method: :delete %>
+    </td>
+  <% end %>
+<% end %>

app/views/measurements/create.turbo_stream.erb

@@ -0,0 +1,5 @@
+<%= turbo_stream.update :flashes %>
+<%= turbo_stream.remove :measurement_form %>
+<%= turbo_stream.remove :no_items %>
+<%= turbo_stream.enable :new_measurement_link %>
+<%= turbo_stream.prepend :measurements, @measurement %>

app/views/measurements/destroy.turbo_stream.erb

@@ -0,0 +1,3 @@
+<%= turbo_stream.update :flashes %>
+<%= turbo_stream.remove @measurement %>
+<%= turbo_stream.append(:measurements, render_no_items) if @measurements_empty %>

config/locales/en.yml

@@ -88,6 +88,12 @@ en:
       select_quantity: select the measured quantities...
     index:
       new_measurement: Add measurement
+    create:
+      success: Measurement saved.
+    destroy:
+      success: Measurement deleted.
+    measurement:
+      destroy: Delete
   readouts:
     form:
       select_unit: ...