god_systems_god_1

gistfile1.coffee

class Ebay
  constructor: ->

    #I'm yet to decide if static vs dynamic roles' assignment 
    #is better. It doesn't matter so much for now

    #extend(@, EbayCanBeWatchedRole)
    #extend(@, SellersCanListRole)



class EbayCanBeWatchedRole


  is_already_watching_item: (seller, item) =>
    storage().is_seller_watching(item)


  seller_wants_to_watch_item: (seller, item) =>
    if @is_already_watching_item(seller, item)
      throw new AlreadyWatching()

    storage().seller_starts_watching(item)


class ListingItemAnswer
  listing_is_valid: () =>
  errors: () =>
  mark_ok: () =>


class SellersCanListRole

  list_items: (seller, item_definition) =>
    answer = new ListingItemAnswer()

    if @is_valid(item_definition) and @can_seller_list(seller)
      @schedule_for_listing(seller, item_definition)
      answer.mark_ok()

    #...