diff options
Diffstat (limited to 'activemodel/lib/active_model/state_machine')
4 files changed, 226 insertions, 0 deletions
diff --git a/activemodel/lib/active_model/state_machine/event.rb b/activemodel/lib/active_model/state_machine/event.rb new file mode 100644 index 0000000000..e8bc8ebdb7 --- /dev/null +++ b/activemodel/lib/active_model/state_machine/event.rb @@ -0,0 +1,62 @@ +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.to_s}!") 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 diff --git a/activemodel/lib/active_model/state_machine/machine.rb b/activemodel/lib/active_model/state_machine/machine.rb new file mode 100644 index 0000000000..170505c0b2 --- /dev/null +++ b/activemodel/lib/active_model/state_machine/machine.rb @@ -0,0 +1,74 @@ +module ActiveModel + module StateMachine + class Machine + attr_accessor :initial_state, :states, :events, :state_index + attr_reader :klass, :name + + def initialize(klass, name, options = {}, &block) + @klass, @name, @states, @state_index, @events = klass, name, [], {}, {} + update(options, &block) + end + + def initial_state + @initial_state ||= (states.first ? states.first.name : nil) + end + + def update(options = {}, &block) + if options.key?(:initial) then @initial_state = options[:initial] end + if block then instance_eval(&block) end + self + end + + def fire_event(event, record, persist, *args) + state_index[record.current_state(@name)].call_action(:exit, record) + if new_state = @events[event].fire(record, *args) + state_index[new_state].call_action(:enter, record) + + if record.respond_to?(event_fired_callback) + record.send(event_fired_callback, record.current_state, new_state) + end + + record.current_state(@name, new_state, persist) + record.send(@events[event].success) if @events[event].success + true + else + if record.respond_to?(event_failed_callback) + record.send(event_failed_callback, event) + end + + false + end + end + + def states_for_select + states.map { |st| [st.display_name, st.name.to_s] } + end + + def events_for(state) + events = @events.values.select { |event| event.transitions_from_state?(state) } + events.map! { |event| event.name } + end + + def current_state_variable + "@#{@name}_current_state" + end + + private + def state(name, options = {}) + @states << (state_index[name] ||= State.new(name, :machine => self)).update(options) + end + + def event(name, options = {}, &block) + (@events[name] ||= Event.new(self, name)).update(options, &block) + end + + def event_fired_callback + @event_fired_callback ||= (@name == :default ? '' : "#{@name}_") + 'event_fired' + end + + def event_failed_callback + @event_failed_callback ||= (@name == :default ? '' : "#{@name}_") + 'event_failed' + end + end + end +end
\ No newline at end of file diff --git a/activemodel/lib/active_model/state_machine/state.rb b/activemodel/lib/active_model/state_machine/state.rb new file mode 100644 index 0000000000..68eb2aa34a --- /dev/null +++ b/activemodel/lib/active_model/state_machine/state.rb @@ -0,0 +1,50 @@ +module ActiveModel + module StateMachine + class State + attr_reader :name, :options + + def initialize(name, options = {}) + @name = name + machine = options.delete(:machine) + if machine + machine.klass.send(:define_method, "#{name}?") do + current_state.to_s == name.to_s + end + end + update(options) + end + + def ==(state) + if state.is_a? Symbol + name == state + else + name == state.name + end + end + + def call_action(action, record) + action = @options[action] + case action + when Symbol, String + record.send(action) + when Proc + action.call(record) + end + end + + def display_name + @display_name ||= name.to_s.gsub(/_/, ' ').capitalize + end + + def for_select + [display_name, name.to_s] + end + + def update(options = {}) + if options.key?(:display) then @display_name = options.delete(:display) end + @options = options + self + end + end + end +end diff --git a/activemodel/lib/active_model/state_machine/state_transition.rb b/activemodel/lib/active_model/state_machine/state_transition.rb new file mode 100644 index 0000000000..f9df998ea4 --- /dev/null +++ b/activemodel/lib/active_model/state_machine/state_transition.rb @@ -0,0 +1,40 @@ +module ActiveModel + module StateMachine + class StateTransition + attr_reader :from, :to, :options + + def initialize(opts) + @from, @to, @guard, @on_transition = opts[:from], opts[:to], opts[:guard], opts[:on_transition] + @options = opts + end + + def perform(obj) + case @guard + when Symbol, String + obj.send(@guard) + when Proc + @guard.call(obj) + else + true + end + end + + def execute(obj, *args) + case @on_transition + when Symbol, String + obj.send(@on_transition, *args) + when Proc + @on_transition.call(obj, *args) + end + end + + def ==(obj) + @from == obj.from && @to == obj.to + end + + def from?(value) + @from == value + end + end + end +end |