gistfile1.rb

class Episode < ActiveRecord::Base
  # accessors
  attr_accessor :flex_video
  
  def video_url
    video.url
  end
  
  def video_url=(url)
    #do nothing
  end
  
  # associations
  belongs_to :channel
  
  has_attached_file :video,
                    :storage => 's3',   
                    :s3_credentials => YAML.load_file("#{RAILS_ROOT}/config/amazon_s3.yml")[RAILS_ENV],
                    :url => ":s3_alias_url",
                    :s3_host_alias => "assets.#{MAIN_HOST}",
                    :path => ":attachment/:id/:style/:basename.:extension"

  # validations
  validates_presence_of :name
  validates_attachment_content_type :video, :content_type => [ "video/x-flv" ]  
  
  # callbacks
  before_validation :check_video_content_type, :if => Proc.new { |episode| episode.flex_video }
  
  #class methods
  
  def self.flex_params  
    {:only => [:id, :name, :approved], :methods => :video_url}
  end
  
  protected
  
  
  private
    
    # Fixes the content type and assigns the video properly before validation
    def check_video_content_type
      self.flex_video.content_type = fix_content_type(self.flex_video.original_filename)      
      self.video = self.flex_video
    end
    
    def fix_content_type(original_filename) #content_type
      if ( original_filename.split(".").last == "flv" )
        content_type = "video/x-flv"
      else
        content_type = MIME::Types.type_for(original_filename).to_s
      end

      return content_type
    end
    
end