better_categorizable.rb

# Usage include Categorizable::Categorized or Categorizable::Categorizable

module Categorizable
  module Categorized
    def self.included(klass)
      associations = [
            [:has_many, :categorings],
            [:has_many, :content_categories, {:through => :categorings}],
            [:has_one,  :primary_categoring, {:conditions => {:primary => true}, :class_name => "Categoring"}],
            [:has_one,  :primary_content_category, {:through => :primary_categoring}]          
          ]
      # showing off bad reflection
      associations.each do |association|
        klass.send( *association )
      end
      klass.send(:include, ::Commons)
    end
    
    def content_category=(content_category)
      Categoring.update_all("`primary` = 0", (self.class == FeedItem) ? "feed_item_id = #{id}" : "categorized_id = #{id} and categorized_type = '#{self.class}'") unless self.new_record?
    
        options = {:categorized => self.publishable}
        categoring = self.categorings(true).first(:conditions => { :content_category_id => content_category.id } ) || 
                     self.publishable.categorings(true).first( :conditions => { :content_category_id => content_category.id } )
    
      if categoring
        categoring.update_attribute(:primary, true) 
      else
        method = new_record? ? :build : :create  
        self.categorings.send(method, options.merge(:content_category => content_category, :primary => true) )
      end
    end
  end
  
  module Categorizable
    def self.included(klass)
      associations = [
            [:has_many, :categorings, {:as => :categorized, :dependent => :destroy}],
            [:has_many, :content_categories, {:through => :categorings}],
            [:has_one,  :primary_categoring, {:as => :categorized, :conditions => {:primary => true}, :class_name => "Categoring"}],
            [:has_one,  :primary_content_category, {:through => :primary_categoring}]
          ]
      # showing off bad reflection
      associations.each do |association|
        klass.send( *association )
      end
      klass.send(:include, ::Commons)
    end


    def content_category=(content_category)

      Categoring.update_all("`primary` = 0", (self.class == FeedItem) ? "feed_item_id = #{id}" : "categorized_id = #{id} and categorized_type = '#{self.class}'") unless self.new_record?

        options = self.class == StockPosition ? {:feed_item => self.feed_items.last} : {:feed_item => self.feed_item}
        categoring = self.categorings(true).first( :conditions => { :content_category_id => content_category.id } )

      if categoring
        categoring.update_attribute(:primary, true) 
      else
        method = new_record? ? :build : :create  
        self.categorings.send(method, options.merge(:content_category => content_category, :primary => true) )
      end
    end
  end
  module Common
    def content_category_id=( category_id )
      self.content_category = ContentCategory.find( category_id ) if category_id
    end

    def content_category_id
      self.content_category.id if self.content_category
    end
  
    def content_category(reload = false)
      return @_content_category if @_content_category && !reload
      if primaries = primary_content_category(reload)
        @_content_category = primaries.all.first
      else
        @_content_category = content_categories(reload).first
      end
    end  
  end
end

nil_pattern.rb

class NilClass
  def method_missing(name, *args, &proc)
    nil
  end
end

research.rb

class Research < ActiveRecord::Base
  # just imagine what it used to look
  (1..8).each do |num|
    has_one "chart#{num}".to_sym, :class_name => "Image", :conditions => {:identifier => "Chart#{num}"}, :dependent => :destroy, :as => :attachable
  end


  # This was actually in the controller 
  (1..8).each do |num|
    define_method "chart#{num}=".to_sym do |params|
      if(params && !params[:uploaded_data].blank?)
        if (send("chart#{num}"))
          send("chart#{num}").update_attributes( params )
        else
          send("build_chart#{num}", {:identifier => "Chart#{num}"}.merge( params || {} ) )
        end
      end
    end
  end
end

wrong_categorizable.rb

module WrongCategorizable
  def self.included(klass)
    associations = {
      :feed_item => [
          [:has_many, :categorings],
          [:has_many, :content_categories, {:through => :categorings}],
          [:has_one,  :primary_categoring, {:conditions => {:primary => true}, :class_name => "Categoring"}],
          [:has_one,  :primary_content_category, {:through => :primary_categoring}]          
        ],
      :categorized => [
          [:has_many, :categorings, {:as => :categorized, :dependent => :destroy}],
          [:has_many, :content_categories, {:through => :categorings}],
          [:has_one,  :primary_categoring, {:as => :categorized, :conditions => {:primary => true}, :class_name => "Categoring"}],
          [:has_one,  :primary_content_category, {:through => :primary_categoring}]
        ]}
    # showing off bad reflection
    associations[(klass == FeedItem) ? :feed_item : :categorized].each do |association|
      klass.send( *association )
    end
  end
  
  def content_category_id=( category_id )
    self.content_category = ContentCategory.find( category_id ) if category_id
  end

  def content_category_id
    self.content_category.id if self.content_category
  end

  def content_category(reload = false)
    return @_content_category if @_content_category && !reload
    if primaries = primary_content_category(reload)
      @_content_category = primaries.all.first
    else
      @_content_category = content_categories(reload).first
    end
  end
  
  
  def content_category=(content_category)
    
    Categoring.update_all("`primary` = 0", (self.class == FeedItem) ? "feed_item_id = #{id}" : "categorized_id = #{id} and categorized_type = '#{self.class}'") unless self.new_record?
    if self.class == FeedItem 
      options = {:categorized => self.publishable}
      categoring = self.categorings(true).first(:conditions => { :content_category_id => content_category.id } ) || 
                   self.publishable.categorings(true).first( :conditions => { :content_category_id => content_category.id } )
    else 
      options = self.class == StockPosition ? {:feed_item => self.feed_items.last} : {:feed_item => self.feed_item}
      categoring = self.categorings(true).first( :conditions => { :content_category_id => content_category.id } )
    end
    
    if categoring
      categoring.update_attribute(:primary, true) 
    else
      method = new_record? ? :build : :create  
      self.categorings.send(method, options.merge(:content_category => content_category, :primary => true) )
    end
  end
end