1 files changed, 22 insertions, 0 deletions

diff --git a/app/controllers/shared_previews_controller.rb b/app/controllers/shared_previews_controller.rb
new file mode 100644
index 0000000..f6fb45a
--- /dev/null
+++ b/app/controllers/shared_previews_controller.rb
@@ -0,0 +1,22 @@
+class SharedPreviewsController < ApplicationController
+  def show
+    @page = Page.find_by!(preview_token: params[:token])
+    node  = @page.node
+
+    if node
+      is_head  = node.head_id  == @page.id
+      is_draft = node.draft_id == @page.id
+
+      currently_public = is_head && @page.public?
+      superseded        = !is_head && !is_draft
+
+      if superseded || currently_public
+        redirect_to @page.public_link
+        return
+      end
+    end
+
+    response.headers['X-Robots-Tag'] = 'noindex'
+    render template: @page.valid_template, layout: "application"
+  end
+end