feature.rb

class Feature
  include Mongoid::Document
  field :body, :type => String

  embedded_in :suggestion, :inverse_of => :features
  has_many_related :votes, :as => :votable
  
end

show.html.erb

# shows a suggestion with all its features and allows voting on both

<p id="notice"><%= notice %></p>

<div class="suggestion">
	
	<div class="voting">
		<h3>
			<span class="plus_votes">+<%= @suggestion.votes.find_all{|vote| vote.value == true}.count %></span> / 
			<span class="minus_votes">-<%= @suggestion.votes.find_all{|vote| vote.value == false}.count %></span>
		</h3>
		your vote?
		<%= form_for([@suggestion, @suggestion.votes.build]) do |f| %>
			<%= f.hidden_field(:value,:value => 1) %>
			<%#= f.submit "+" %>
			<button><%= image_tag("plus.png") %> agree</button>
		<% end %>
		<%= form_for([@suggestion, @suggestion.votes.build]) do |f| %>
			<%= f.hidden_field(:value,:value => 0) %>
			<%#= f.submit "-" %>
			<button><%= image_tag("minus.png") %> disagree</button>
		<% end %>
	</div><!-- .voting -->          
	
	<div class="body">
		<h3><%= @suggestion.title %></h3>
		<p><%= @suggestion.body %></p>
		
		
			<h4>Features</h4>
			<% @features.each do |feature| %>
				<div class="feature">
					<div class="voting">
						<span class="plus_votes">+<%= feature.votes.find_all{|vote| vote.value == true}.count %></span> / 
						<span class="minus_votes">-<%= feature.votes.find_all{|vote| vote.value == false}.count %></span> 

						<%= form_for([@suggestion, feature, feature.votes.build]) do |f| %>
							<%= f.hidden_field(:value,:value => 1) %>
							<%#= f.submit "+" %>
							<button><%= image_tag("plus.png") %> agree</button>
						<% end %>
						<%= form_for([@suggestion, feature, feature.votes.build]) do |f| %>
							<%= f.hidden_field(:value,:value => 0) %>
							<%#= f.submit "-" %>
							<button><%= image_tag("minus.png") %> disagree</button>
						<% end %>
					</div><!-- .voting -->
					<div class="body">
						<%= feature.body %>
					</div><!-- .body -->
					
						<%= link_to "Edit", edit_suggestion_feature_path(@suggestion, feature) %> | 
						<%= link_to "Delete", suggestion_feature_path(@suggestion,feature), :confirm => 'Are you sure?', :method => :delete %>
					<!-- TODO edit and delete for admin only -->
				</div><!-- .feature -->
			<% end %>
      
			<hr class="cleaner" />

			<h4>Add a feature</h4>
			<%= form_for([@suggestion, @suggestion.features.build]) do |f| %>
				<%= f.text_area :body %><br />
				<%= f.submit "Add a feature" %>
			<% end %>
		
	</div><!-- .body -->
	
</div><!-- .suggestion -->

<hr class="cleaner" />


<%= link_to 'Edit', edit_suggestion_path(@suggestion) %> |
<%= link_to 'Back', suggestions_path %>

suggestion.rb

class Suggestion
  include Mongoid::Document
  
  field :title, :type => String
  field :body, :type => String
  field :slug, :type => String
  
  has_many_related :votes, :as => :votable
  embeds_many :features
  
  validates_presence_of :title, :body
  validates_uniqueness_of :title, :slug
  
  def to_param
    slug
  end

end

vote.rb

class Vote
  include Mongoid::Document
  field :value, :type => Boolean

  belongs_to_related :suggestion
  belongs_to_related :feature
  # This way each Vote has both suggestion_id and feature_id field
end

votes_controller.rb

# just create method:

  def create

    if params[:feature_id].nil? # casting vote on Feature or Suggestion? - ugly implementation of polymorphism...
      # cast vote on Suggestion
      suggestion = Suggestion.where(:slug => params[:suggestion_id]).first
      params[:suggestion_id] = suggestion.id # replace slug with id
      @vote = Vote.new(params[:vote])
      suggestion.votes << @vote
    else
      # cast vote on Feature
      suggestion = Suggestion.where(:slug => params[:suggestion_id]).first
      feature = suggestion.features.find(params[:feature_id])
      @vote = Vote.new(params[:vote])
      feature.votes << @vote
    end