Added parameter with col_sep

app/views/admin/import.html.erb

@@ -1,11 +1,13 @@
 <p class="active_admin_import_hint">
-   <%= raw(@active_admin_import_model.hint) %> 
+   <%= raw(@active_admin_import_model.hint) %>
 </p>
 <%= semantic_form_for @active_admin_import_model, url: {action: :do_import}, html: {multipart: true} do |f| %>
     <%= f.inputs name: t("active_admin_import.details") do %>
         <%= f.input :file, as: :file %>
+        <%= f.input :col_sep, collection: [';', ','], include_blank: false %>
     <% end %>
+
     <%= f.actions do %>
         <%= f.action :submit, label: t("active_admin_import.import_btn"), button_html: {data: {disable_with: t("active_admin_import.import_btn_disabled")}} %>
     <% end %>
-<% end %>
+<% end %>

lib/active_admin_import/importer.rb

@@ -172,6 +172,7 @@ def detect_csv_options
                      else
                        options[:csv_options] || {}
                      end.reject { |_, value| value.nil? || value == "" }
+      @csv_options[:col_sep] = model.col_sep if model.respond_to?(:col_sep)
     end
   end
 end

lib/active_admin_import/model.rb

@@ -65,7 +65,8 @@ def default_attributes
         csv_headers: [],
         file: nil,
         force_encoding: 'UTF-8',
-        hint: ''
+        hint: '',
+        col_sep: ';'
       }
     end