     }
 
   kick_off: () -> @switch_scene('welcome')
+
+  next_stage: () ->
+    @configs['current_stage'] = (@configs['current_stage'] + 1
+      + @configs['stages']) % @configs['stages']
+    if @configs['current_stage'] == 0
+      @configs['current_stage'] = @configs['stages']
+    @configs['current_stage']
 
   reset: () ->
     _.each @scenes, (scene) -> scene.stop()

    @enemy_win() if (@remain_user_p1_lives == 0 and @remain_user_p2_lives == 0)

  user_win: () ->
    console.log "user win!"
    setTimeout((() => @game.switch_scene('report')), 5000)

  enemy_win: () ->
    # hi score or
    # welcome
    console.log "enemy win!"
    # setTimeout(() =>
    #   @game.switch_scene('welcome')
    # , 10000)

  born_tanks: (tank) ->
    if tank instanceof UserP1Tank

      switch event.which
        when 37, 38
          # UP, LEFT
          @current_stage = @game.prev_stage()
          @update_stage_label()
        when 39, 40
          # RIGHT, DOWN
          @current_stage = @game.next_stage()
          @update_stage_label()
        when 13
          # ENTER
          @game.switch_scene('game')

  disable_stage_control: () ->
    $(document).unbind "keydown"

  init_stage_nodes: () ->
    # bg
