get all products from category tree

gistfile1.rb

# category.rb

class Category < ActiveRecord::Base
    acts_as_nested_set
  
    attr_accessible :name, :description, :lft, :rgt, :parent_id   
    
    has_many :categorizations
    has_many :products, :through => :categorizations
    
    attr_accessor :product_list
    
    def branch_ids
      self_and_descendants.map(&:id).uniq 
    end
    

    def all_products
       Category.find(branch_ids).map(&:products) 
    end    
end

#categorization.rb
class Categorization < ActiveRecord::Base
  belongs_to :product
  belongs_to :category
end

# products_controller.rb

class ProductsController < ApplicationController
  before_filter :authenticate_user!, :except => [:index, :show]
  
  def index
    if params[:category]
      @category = Category.find(params[:category])
      @products = @category.all_products # <-- get all products
    else
      @category = false
      @products = Product.scoped
    end
    @products = @products.where("title like ?", "%" + params[:title] + "%") if params[:title]
    @products = @products.order("created_at").page(params[:page]).per( params[:per_page] ? params[:per_page] : 12)
    @categories = Category.all
  end

 #...

end


# console output

ruby-1.9.2-p136 :020 > c = Category.first
 => #<Category id: 6, name: "Woman", description: "woman stuff", created_at: "2011-08-24 13:10:11", updated_at: "2011-08-24 13:10:11", parent_id: nil, lft: 1, rgt: 6> 
ruby-1.9.2-p136 :021 > Category.find(c.branch_ids).map(&:products) 
 => [[#<Product id: 12, description: "test", price: 398000, created_at: "2011-07-11 10:48:13", updated_at: "2011-07-11 10:48:13", title: "Jewels", subtitle: "diamant", currency: "GBP", legacy: nil>], [], [#<Product id: 12, description: "test", price: 398000, created_at: "2011-07-11 10:48:13", updated_at: "2011-07-11 10:48:13", title: "Jewels", subtitle: "diamant", currency: "GBP", legacy: nil>]] 
ruby-1.9.2-p136 :022 > 


# output needed to be able to order and paginate products (example with only one category)

uby-1.9.2-p136 :022 > c = Category.first
 => #<Category id: 6, name: "Woman", description: "woman stuff", created_at: "2011-08-24 13:10:11", updated_at: "2011-08-24 13:10:11", parent_id: nil, lft: 1, rgt: 6> 
ruby-1.9.2-p136 :023 > c.products
 => [#<Product id: 12, description: "test", price: 398000, created_at: "2011-07-11 10:48:13", updated_at: "2011-07-11 10:48:13", title: "Jewels", subtitle: "diamant", currency: "GBP", legacy: nil>] 
ruby-1.9.2-p136 :024 >