Rails: Create a custom UI for a single specific object

I've run into a problem I'm completely unsure how to approach.

I have an app for sharing architectural photos. Users have_many Photos, and users can create Collections which also have_many Photos.

Now I have one customer who is a big name in the industry who would like to work with me to create a totally customized Collection with a very different look and feel from "regular" collections, but essentially the same functionality underneath. I'd like to accommodate this request, but I really have no idea how to do it.

Given that I already have a functioning Collection model and CollectionsController, plus all the views, I'd like to re-use as much of that as possible. So, for instance, the custom Collection needs to override the user facing :show view, but not the admin :edit view.

How would you approach something like this?

I'm trying to understand the most efficient, DRY method for creating a completely custom UI for a single record in the database. I'd be very appreciative of suggest开发者_如何学编程ions, including links to articles / books etc, as I haven't been able to find much in this area.

I would allow the creation of Liquid view templates associated with a User and/or Collection (if you want both - per-user templates with per-collection variations - use a polymorphic association) and of course fall back to your default view (also built with Liquid for consistency and reference) for all cases where no custom template is found.

Edit to add suggested details:

Any custom templates should be stored in the database (I would add a test/preview function so the user entering a custom template has the chance to verify their template before publishing it):

# Table name custom_templates
# id               :integer
# templatable_type :string
# templatable_id   :integer
# contents         :text
class CustomTemplate < ActiveRecord::Base
  belongs_to :templatable, :polymorphic => true
end
class User
  has_one :custom_template, :as => :templatable    
end
class Collection
  has_one :custom_template, :as => :templatable
end

In your controller action, look for a custom template:

custom_template   = @collection.custom_template
custom_template ||= @user.custom_template
@custom_template = Liquid::Template.parse(custom_template.contents) if custom_template

In your view, either render the custom template or your default template partial:

<% if @custom_template -%>
  <%= @custom_template.render(_hash_of_objects_to_pass_to_liquid_template_) %>
<% else -%>
  <%= render :partial => 'default' %>
<% end -%>