add merge button

app/controllers/models_controller.rb

@@ -16,6 +16,15 @@ def update
     redirect_to [@library, @model]
   end
 
+  def merge
+    if (@parent = @model.parent)
+      @model.merge_into_parent!
+      redirect_to [@library, @parent]
+    else
+      render status: :bad_request
+    end
+  end
+
   def bulk_edit
     @creators = Creator.all
     @models = @library.models

app/views/models/show.html.erb

@@ -33,6 +33,7 @@
 
     <%= card :secondary, "Actions" do %>
       <%= link_to "Edit Details", edit_library_model_path(@library, @model), class: "btn btn-primary" %>
+      <%= link_to "Merge Into Parent", merge_library_model_path(@library, @model), class: "btn btn-danger", method: :post if @model.parent %>
     <% end %>
 
     <%= render 'tags_card', tags: @model.tags, selected: nil %>

config/routes.rb

@@ -3,6 +3,9 @@
   post "/", controller: :search, action: :index
   resources :libraries do
     resources :models, except: [:index, :destroy] do
+      member do
+        post "merge"
+      end
       collection do
         get "edit", action: "bulk_edit"
         patch "update", action: "bulk_update"