Respect Language public status for Page public status

A page is only considered public if the language is also public. This is
always the case for the default language, because there cannot be at
least one public default language (assurred in the language validations).

app/models/alchemy/page/page_natures.rb

@@ -6,7 +6,7 @@ module Page::PageNatures
 
     def public?
       current_time = Time.current
-      already_public_for?(current_time) && still_public_for?(current_time)
+      language.public? && already_public_for?(current_time) && still_public_for?(current_time)
     end
 
     def expiration_time

app/models/alchemy/page/page_scopes.rb

@@ -96,6 +96,7 @@ module ClassMethods
       # All public pages
       #
       def published
+        joins(:language).merge(Language.published).
         where("#{table_name}.public_on <= :time AND " \
               "(#{table_name}.public_until IS NULL " \
               "OR #{table_name}.public_until >= :time)", time: Time.current)

spec/models/alchemy/page_spec.rb

@@ -558,11 +558,14 @@ class AnotherUrlPathClass; end
       let!(:public_one) { create(:alchemy_page, :public) }
       let!(:public_two) { create(:alchemy_page, :public) }
       let!(:non_public_page) { create(:alchemy_page) }
+      let!(:page_with_non_public_language) { create(:alchemy_page, :public, language: non_public_language) }
+      let(:non_public_language) { create(:alchemy_language, :german, public: false) }
 
       it "returns public available pages" do
         expect(published).to include(public_one)
         expect(published).to include(public_two)
         expect(published).to_not include(non_public_page)
+        expect(published).to_not include(page_with_non_public_language)
       end
     end
 
@@ -1314,6 +1317,13 @@ class AnotherUrlPathClass; end
 
         it { is_expected.to be(false) }
       end
+
+      context "when language is not public" do
+        let(:language) { create(:alchemy_language, public: false, default: false) }
+        let(:page) { create(:alchemy_page, :public, language: language) }
+
+        it { is_expected.to be(false) }
+      end
     end
 
     describe "#publish!" do