Extract model to handle locales settings

This way we can simplify the view, particularly the form. However, we're
still adding some complexity to the form so inputs are inside labels and
so the collection is easier to style with CSS.

app/assets/stylesheets/admin/locales/form.scss

@@ -7,6 +7,10 @@
     width: auto;
   }
 
+  .help-text {
+    display: block;
+  }
+
   > select + fieldset,
   > fieldset + fieldset {
     margin-top: $line-height / 2;

app/components/admin/locales/form_component.html.erb

@@ -1,37 +1,36 @@
-<%= form_tag admin_locales_path, method: :patch, class: "locales-form" do %>
+<%= form_for locales_settings, url: admin_locales_path, html: { class: "locales-form" } do |f| %>
   <% if many_available_locales? %>
-    <%= label_tag "default_locale", t("admin.locales.default") %>
-    <p class="help-text"><%= sanitize(t("admin.locales.default_help_text")) %></p>
-    <%= select_tag "default_locale", locales_options %>
+    <%= f.select :default, locales_options, hint: sanitize(t("admin.locales.default_help_text")) %>
   <% else %>
     <fieldset>
-      <legend><%= t("admin.locales.default") %></legend>
+      <legend><%= attribute_name(:default) %></legend>
       <p class="help-text"><%= sanitize(t("admin.locales.default_help_text")) %></p>
 
       <div class="collection-radio-buttons">
-        <% available_locales.each do |locale| %>
-          <%= label_tag "default_locale_#{locale}" do %>
-            <%= radio_button_tag "default_locale", locale, locale == default %>
-            <%= name_for_locale(locale) %>
-          <% end %>
+        <%= f.collection_radio_buttons(
+          :default,
+          available_locales,
+          :to_sym,
+          ->(locale) { name_for_locale(locale) }
+        ) do |b| %>
+          <%= b.label { b.radio_button + b.text } %>
         <% end %>
       </div>
     </fieldset>
   <% end %>
 
   <fieldset>
-    <legend><%= t("admin.locales.enabled") %></legend>
+    <legend><%= attribute_name(:enabled) %></legend>
     <p class="help-text"><%= t("admin.locales.enabled_help_text") %></p>
 
     <div class="collection-check-boxes">
-      <% available_locales.each do |locale| %>
-        <%= label_tag "enabled_locales_#{locale}" do %>
-          <%= check_box_tag "enabled_locales[]",
-                            locale,
-                            enabled_locales.include?(locale),
-                            id: "enabled_locales_#{locale}" %>
-          <%= name_for_locale(locale) %>
-        <% end %>
+      <%= f.collection_check_boxes(
+        :enabled,
+        available_locales,
+        :to_sym,
+        ->(locale) { name_for_locale(locale) }
+      ) do |b| %>
+        <%= b.label { b.check_box + b.text } %>
       <% end %>
     </div>
   </fieldset>

app/components/admin/locales/form_component.rb

@@ -1,10 +1,9 @@
 class Admin::Locales::FormComponent < ApplicationComponent
-  attr_reader :enabled_locales, :default
+  attr_reader :locales_settings
   use_helpers :name_for_locale
 
-  def initialize(enabled_locales, default:)
-    @enabled_locales = enabled_locales
-    @default = default
+  def initialize(locales_settings)
+    @locales_settings = locales_settings
   end
 
   private
@@ -18,13 +17,14 @@ class Admin::Locales::FormComponent < ApplicationComponent
     end
 
     def locales_options
-      options_for_select(
-        available_locales.map { |locale| [name_for_locale(locale), locale] },
-        default
-      )
+      available_locales.map { |locale| [name_for_locale(locale), locale] }
     end
 
     def select_field_threshold
       10
     end
+
+    def attribute_name(...)
+      locales_settings.class.human_attribute_name(...)
+    end
 end

app/components/admin/locales/show_component.html.erb

@@ -1,4 +1,4 @@
 <%= header %>
 <% provide :main_class, "admin-locales-show" %>
 
-<%= render Admin::Locales::FormComponent.new(locales, default: default) %>
+<%= render Admin::Locales::FormComponent.new(locales_settings) %>

app/components/admin/locales/show_component.rb

@@ -1,10 +1,9 @@
 class Admin::Locales::ShowComponent < ApplicationComponent
   include Header
-  attr_reader :locales, :default
+  attr_reader :locales_settings
 
-  def initialize(locales, default:)
-    @locales = locales
-    @default = default
+  def initialize(locales_settings)
+    @locales_settings = locales_settings
   end
 
   def title

app/controllers/admin/locales_controller.rb

@@ -1,15 +1,27 @@
 class Admin::LocalesController < Admin::BaseController
+  before_action :set_locales_settings
+  authorize_resource :locales_settings
+
   def show
-    @enabled_locales = Setting.enabled_locales
-    @default_locale = Setting.default_locale
   end
 
   def update
-    Setting.transaction do
-      Setting["locales.default"] = params["default_locale"]
-      Setting["locales.enabled"] = [params["default_locale"], *params["enabled_locales"]].join(" ")
-    end
+    @locales_settings.update!(locales_settings_params)
 
     redirect_to admin_locales_path, notice: t("admin.locales.update.notice")
   end
+
+  private
+
+    def locales_settings_params
+      params.require(:setting_locales_settings).permit(allowed_params)
+    end
+
+    def allowed_params
+      [:default, enabled: []]
+    end
+
+    def set_locales_settings
+      @locales_settings = Setting::LocalesSettings.new
+    end
 end

app/models/abilities/administrator.rb

@@ -134,6 +134,8 @@ module Abilities
       can [:deliver], Newsletter, hidden_at: nil
       can [:manage], Dashboard::AdministratorTask
 
+      can :manage, Setting::LocalesSettings
+
       can :manage, LocalCensusRecord
       can [:create, :read], LocalCensusRecords::Import
 

app/models/setting/locales_settings.rb

@@ -0,0 +1,23 @@
+class Setting
+  class LocalesSettings
+    include ActiveModel::Model
+    include ActiveModel::Attributes
+
+    attribute :enabled, array: true, default: -> { Setting.enabled_locales }
+    attribute :default, default: -> { Setting.default_locale }
+
+    def persisted?
+      true
+    end
+
+    def update(attributes)
+      assign_attributes(attributes)
+
+      Setting.transaction do
+        Setting["locales.default"] = default
+        Setting["locales.enabled"] = [default, *enabled].join(" ")
+      end
+    end
+    alias_method :update!, :update
+  end
+end

app/views/admin/locales/show.html.erb

@@ -1 +1 @@
-<%= render Admin::Locales::ShowComponent.new(@enabled_locales, default: @default_locale) %>
+<%= render Admin::Locales::ShowComponent.new(@locales_settings) %>

config/locales/en/activemodel.yml

@@ -38,6 +38,9 @@ en:
         year_of_birth: "Year born"
       local_census_records/import:
         file: File
+      setting/locales_settings:
+        default: Default language
+        enabled: Enabled languages
     errors:
       models:
         local_census_records/import:

config/locales/en/admin.yml

@@ -711,9 +711,7 @@ en:
         index:
           title: Following
     locales:
-      default: Default language
       default_help_text: "This is the default language of the application, and changing it will <strong>affect every user</strong> visiting the website for the first time."
-      enabled: Enabled languages
       enabled_help_text: The default language, selected above, will be included automatically.
       update:
         notice: Languages updated successfully

config/locales/es/activemodel.yml

@@ -38,6 +38,9 @@ es:
         year_of_birth: "Año de nacimiento"
       local_census_records/import:
         file: Archivo
+      setting/locales_settings:
+        default: Idioma por defecto
+        enabled: Idiomas habilitados
     errors:
       models:
         local_census_records/import:

config/locales/es/admin.yml

@@ -711,9 +711,7 @@ es:
         index:
           title: Seguimiento
     locales:
-      default: Idioma por defecto
       default_help_text: "Cambiar el idioma por defecto <strong>afectará a todos los usuarios</strong> que visiten la página por primera vez."
-      enabled: Idiomas habilitados
       enabled_help_text: El idioma por defecto, seleccionado con anterioridad, se habilitará automáticamente.
       update:
         notice: Idiomas actualizados con éxito

spec/components/admin/locales/form_component_spec.rb

@@ -3,10 +3,8 @@ require "rails_helper"
 describe Admin::Locales::FormComponent do
   let(:default_locale) { :nl }
   let(:enabled_locales) { %i[en nl] }
-
-  let(:component) do
-    Admin::Locales::FormComponent.new(enabled_locales, default: default_locale)
-  end
+  let(:locales_settings) { Setting::LocalesSettings.new(default: default_locale, enabled: enabled_locales) }
+  let(:component) { Admin::Locales::FormComponent.new(locales_settings) }
 
   describe "default language selector" do
     before { allow(I18n).to receive(:available_locales).and_return(%i[de en es nl]) }

spec/models/setting/locales_settings_spec.rb

@@ -0,0 +1,13 @@
+require "rails_helper"
+
+describe Setting::LocalesSettings do
+  describe "#update!" do
+    it "saves the default locale in the enabled ones when nothing is enabled" do
+      Setting::LocalesSettings.new.update!(default: "es", enabled: %w[])
+      updated_locales_settings = Setting::LocalesSettings.new
+
+      expect(updated_locales_settings.default).to eq :es
+      expect(updated_locales_settings.enabled).to match_array [:es]
+    end
+  end
+end