FEATURE: Theme settings (2) (#5611)

Allows theme authors to specify custom theme settings for the theme. 

Centralizes the theme/site settings into a single construct

app/serializers/theme_serializer.rb

@@ -24,11 +24,7 @@ class ThemeFieldSerializer < ApplicationSerializer
   end
 
   def target
-    case object.target_id
-    when 0 then "common"
-    when 1 then "desktop"
-    when 2 then "mobile"
-    end
+    Theme.lookup_target(object.target_id)&.to_s
   end
 
   def include_error?
@@ -60,7 +56,7 @@ class RemoteThemeSerializer < ApplicationSerializer
 end
 
 class ThemeSerializer < ChildThemeSerializer
-  attributes :color_scheme, :color_scheme_id, :user_selectable, :remote_theme_id
+  attributes :color_scheme, :color_scheme_id, :user_selectable, :remote_theme_id, :settings
 
   has_many :theme_fields, serializer: ThemeFieldSerializer, embed: :objects
   has_many :child_themes, serializer: ChildThemeSerializer, embed: :objects
@@ -69,6 +65,10 @@ class ThemeSerializer < ChildThemeSerializer
   def child_themes
     object.child_themes.order(:name)
   end
+
+  def settings
+    object.settings.map { |setting| ThemeSettingsSerializer.new(setting, root: false) }
+  end
 end
 
 class ThemeFieldWithEmbeddedUploadsSerializer < ThemeFieldSerializer
@@ -94,4 +94,8 @@ end
 
 class ThemeWithEmbeddedUploadsSerializer < ThemeSerializer
   has_many :theme_fields, serializer: ThemeFieldWithEmbeddedUploadsSerializer, embed: :objects
+
+  def include_settings?
+    false
+  end
 end

app/serializers/theme_settings_serializer.rb

@@ -0,0 +1,35 @@
+class ThemeSettingsSerializer < ApplicationSerializer
+  attributes :setting, :type, :default, :value, :description, :valid_values
+
+  def setting
+    object.name
+  end
+
+  def type
+    object.type_name
+  end
+
+  def default
+    object.default
+  end
+
+  def value
+    object.value
+  end
+
+  def description
+    object.description
+  end
+
+  def valid_values
+    object.choices
+  end
+
+  def include_valid_values?
+    object.type == ThemeSetting.types[:enum]
+  end
+
+  def include_description?
+    object.description.present?
+  end
+end