## production.log
Processing ProductsController#admin_update (for 72.128.34.48 at 2009-12-07 23:48:36) [POST]
  Parameters: {"commit"=>"Update", "authenticity_token"=>"SYorMTYI6GiZm0MS/fRlR9GcfdKSJ6FLFb/zKpvgMGI=", "product"=>{"name"=>"Japanese Flag Buckle", "price"=>"11.99", "quantity"=>"3", "desc"=>"How much do we love Japan? Let us count the ways!  Pay tribute to the country that brings us Anime, Ninjas, and Robots! Need we say more?  How about the Earthquake Bed and the Cat Booty Dusters? OK, lets stick to the first three...  Measures 3 ", "category_id"=>["27"], "item_number"=>"BKL2"}, "id"=>"21-japanese-flag-buckle"}

ActiveRecord::RecordInvalid (Validation failed: Category is not a number):
  app/controllers/products_controller.rb:86:in `admin_update'
  dispatch.fcgi:24

Rendering /home/klutch/shop/public/422.html (422 Unprocessable Entity)

## products_controller.rb
  def admin_update
    @product = Product.find_by_id(params[:id])
    if(@product.update_attributes!(params[:product])) # <-- line 86
      @product.update_categories(params[:product][:category_id])
      redirect_to :action => 'admin_list'
    else
      render :xml => @product
    end
  end

## product.rb
def update_categories(category_ids)
    bridges = CategoryProduct.find(:all, :conditions  => {:product_id => id})
    bridge_category_ids = []
    bridges.each do |bridge|
      bridge_category_ids.push(bridge.category_id)
    end

    # Create bridges with ids from category_ids
    category_ids.each do |category_id|
      unless(bridge_category_ids.include?(category_id))
        bridge = CategoryProduct.new(:product_id => id, :category_id => category_id)
        bridge.save
      end
    end

    # Remove bridges whose ids aren't listed in category_ids
    bridge_category_ids.each do |bridge_category_id|
      unless(category_ids.include?(bridge_category_id))
        bridge = CategoryProduct.find(	:first,
					:conditions => {
						:product_id => id,
						:category_id => bridge_category_id})
        bridge.destroy
      end
    end
  end