Before extracting workflow object

quotation.rb

class Quotation

  include DataMapper::Resource
  # ...snip...
  property :quoted_kms, Float
  property :quoted_per_km, Float
  property :quoted_price, Float

  property :start_date, Date, :required => true
  property :end_date, Date, :required => true
  # ...snip...
  
  def unconfirmed?
    [:mildly_interested, :negotiating].include?(quality)
  end

  def expirable?
    true if self.start_date <= Date.today
  end

  def sendable?
    (approved? || sent?) && !intended_trip.user.email.blank? && !expirable?
  end

  def approvable?
    set_end_date
    (start_date && end_date) && !sent? && !unconfirmed? && !approved? && !expirable? 
  end
  
  #... loads of small functions that check whats possible to do with the Quotation in its current state
  
  workflow do
    state :created do
      event :approve, :transitions_to => :approved, :if => Proc.new{|t| t.approvable? }
      event :reject, :transitions_to => :rejected, :if => Proc.new{|t| t.rejectable? }
      event :hold, :transitions_to => :on_hold, :if => Proc.new{|t| t.on_holdable? }
      event :expire, :transitions_to => :expired, :if => Proc.new{|t| t.expirable? }
      event :callback, :transitions_to => :callback, :if => Proc.new{|t| t.callbackable? }
    end
    state :approved do
      event :send_quotation, :transitions_to => :sent, :if => Proc.new{|t| t.sendable? }
      event :reject, :transitions_to => :rejected, :if => Proc.new{|t| t.rejectable? }
      event :hold, :transitions_to => :on_hold, :if => Proc.new{|t| t.on_holdable? }
      event :pay, :transitions_to => :paid, :if => Proc.new{|t| t.payable? }
      event :expire, :transitions_to => :expired, :if => Proc.new{|t| t.expirable? }
    end  
    #... snip ...  
    end
    # ..snip ..
  end 
  
  def send_quotation(doer, params = {})
    valid?
    UserMailer.quotation(self).deliver
    self.sent_at = DateTime.now
    Transaction.all(:amount.lte => 0, :quotation => self).destroy
    t = Transaction.create(:amount => -quoted_price, :date => Date.today, :user => self.intended_trip.user, :created_by => doer, :comment => "#{doer.email} sent quotation", :quotation => self)
  end

  def pay(doer, params = {})
    t = Transaction.create(:amount => quoted_price, :date => Date.today, :user => self.intended_trip.user, :created_by => doer, :comment => "#{doer.email} marked as 'Paid'", :quotation => self)
  end
  
  # some more actions to be done on state transition
  
  # loads of other methods to do with the Quotation proper
  
end