class Episode < ActiveRecord::Base

  attr_protected :permalink

  belongs_to :program
  
  validates_presence_of   :title
  validates_uniqueness_of :title
  validates_associated    :program

  # TODO This requires that a value be entered for each of these, 
  #      which is not always the case.
  #
  # validates_numericality_of :mp3_length
  # validates_numericality_of :mp4_length

  def before_create
    @attributes['permalink'] = @attributes['title'].downcase.gsub(/\s+/, '-').gsub(/[^a-zA-Z0-9_\-]+/, '')
    @attributes['published_at'] = Time.now.utc if @attributes['published_at'].blank?
  end

  def before_save
    if has_transcript && transcript_published_at.blank?
      @attributes['transcript_published_at'] = Time.now.utc
    end
  end

  ##
  # Makes urls search-engine friendly.
  #
  #  /programs/1/episodes/bart_simpson
  #
  def to_param
    permalink
  end

  # TODO
  #      Resolve relative paths for mp3_url: /..., a..., http://...
  #      

  # TODO
  #      Set transcript_published_at if has_transcript was updated

end