require 'active_model/state_machine/state_transition' module ActiveModel module StateMachine class Event attr_reader :name, :success def initialize(machine, name, options = {}, &block) @machine, @name, @transitions = machine, name, [] if machine machine.klass.send(:define_method, "#{name}!") do |*args| machine.fire_event(name, self, true, *args) end machine.klass.send(:define_method, name.to_s) do |*args| machine.fire_event(name, self, false, *args) end end update(options, &block) end def fire(obj, to_state = nil, *args) transitions = @transitions.select { |t| t.from == obj.current_state(@machine ? @machine.name : nil) } raise InvalidTransition if transitions.size == 0 next_state = nil transitions.each do |transition| next if to_state && !Array(transition.to).include?(to_state) if transition.perform(obj) next_state = to_state || Array(transition.to).first transition.execute(obj, *args) break end end next_state end def transitions_from_state?(state) @transitions.any? { |t| t.from? state } end def ==(event) if event.is_a? Symbol name == event else name == event.name end end def update(options = {}, &block) if options.key?(:success) then @success = options[:success] end if block then instance_eval(&block) end self end private def transitions(trans_opts) Array(trans_opts[:from]).each do |s| @transitions << StateTransition.new(trans_opts.merge({:from => s.to_sym})) end end end end end