gistfile1.rb

>> Review.detect?("Rating: 4\nItem: Dyson\n\nThis should be the description.")
=> true
>> Chat.detect?("You: Hello\nMe: Hello back at ya!\nYou: Wanna go eat\nYou: Somehwere\nMe: Yes!")
=> true
>> Chat.detect?("Rating: 4\nItem: Dyson\n\nThis should be the description.")
=> false
>> Review.detect?("You: Hello\nMe: Hello back at ya!\nYou: Wanna go eat\nYou: Somehwere\nMe: Yes!")
=> false

# The code that makes this work

  # can be overriden to provide auto detection of type from a block of text
  #
  # Examples:
  #   def self.detect?(text)
  #     has_keys? text, :title, :body
  #   end
  #
  #   def self.detect?(text)
  #     has_required? text
  #   end
  #
  #   def self.detect?(text)
  #     has_one_or_more? text, :me
  #   end
  #
  def self.detect?(text)
    false
  end
  
  # useful for detection
  def self.has_keys?(text, *fields)
    needed = fields.make_attrs
    get_pairs_count(text, needed).length == needed.length
  end
  
  def self.has_more_than_one?(text, field)
    has_more_than? text, field, 1
  end
  
  def self.has_one_or_more?(text, field)
    has_more_than? text, field, 0
  end
  
  def self.has_more_than?(text, field, amount)
    get_pairs_count(text, [field]).length > amount
  end
  
  def self.get_pairs(text)
    TextImporter.new(self).import(text)
  end
  
  def self.get_pairs_count(text, fields)
    pairs = get_pairs(text)
    pairs.reject { |pair| !fields.include?(pair.keys.first) }
  end
  
  def self.has_required?(text)
    has_keys? text, *self.required_fields_list
  end
  
  # runs through the list of children looking for one that will work
  def self.auto_detect(text)
    list = self.preferred_order.blank? ? @all_children : self.preferred_order
    
    list.each { |l| return l.new(text) if l.detect?(text) }
  end