Use Rails standards for deleting pages from EssencePage (AlchemyCMS#1833

)

Rails offers ways for setting relations, let's use them.

app/models/alchemy/essence_page.rb

@@ -2,8 +2,6 @@
 
 module Alchemy
   class EssencePage < BaseRecord
-    PAGE_ID = /\A\d+\z/
-
     acts_as_essence(
       ingredient_column: :page,
       preview_text_method: :name,
@@ -14,16 +12,5 @@ class EssencePage < BaseRecord
         optional: true,
       },
     )
-
-    def ingredient=(page)
-      case page
-      when PAGE_ID
-        self.page = Alchemy::Page.new(id: page)
-      when Alchemy::Page
-        self.page = page
-      else
-        super
-      end
-    end
   end
 end

app/views/alchemy/essences/_essence_page_editor.html.erb

@@ -4,7 +4,7 @@
   data: essence_page_editor.data_attributes do %>
   <%= content_label(essence_page_editor) %>
   <%= text_field_tag(
-    essence_page_editor.form_field_name,
+    essence_page_editor.form_field_name("page_id"),
     essence_page_editor.essence.page_id,
     id: essence_page_editor.form_field_id,
     class: 'alchemy_selectbox full_width'

spec/models/alchemy/essence_page_spec.rb

@@ -18,44 +18,4 @@
       expect(essences[0].association(:ingredient_association)).to be_loaded
     end
   end
-
-  describe "ingredient=" do
-    subject(:ingredient) { essence.page }
-
-    context "when String value is only a number" do
-      let(:value) { "101" }
-
-      before do
-        essence.ingredient = value
-      end
-
-      it "sets page to an page instance with that id" do
-        is_expected.to be_a(Alchemy::Page)
-        expect(ingredient.id).to eq(101)
-      end
-    end
-
-    context "when value is an Alchemy Page" do
-      let(:value) { page }
-
-      before do
-        essence.ingredient = value
-      end
-
-      it "sets page to an page instance with that id" do
-        is_expected.to be_a(Alchemy::Page)
-        expect(ingredient).to eq(page)
-      end
-    end
-
-    context "when value is not only a number" do
-      let(:value) { "page1" }
-
-      it do
-        expect {
-          essence.ingredient = value
-        }.to raise_error(ActiveRecord::AssociationTypeMismatch)
-      end
-    end
-  end
 end