# -*- encoding : utf-8 -*-


class Card
  module FollowOption
    mattr_reader :test, :follower_candidate_ids
    @@test, @@follower_candidate_ids = {}, {}

    @@options = { all: [], main: [], restrictive: [] }

    def self.included(host_class)
       host_class.extend ClassMethods
    end

    def self.codenames type=:all
      @@options[type]
    end

    def self.cards
       codenames.map { |codename| Card[codename] }
    end

    def self.restrictive_options
      self.codenames :restrictive
    end

    def self.main_options
      self.codenames :main
    end

    def restrictive_option?
      Card::FollowOption.restrictive_options.include? codename
    end

    def description set_card
      set_card.follow_label
    end

    module ClassMethods

      # args:
      # position: <Fixnum> (starting at 1, default: add to end)
      def restrictive_follow_opts args
        add_option args, :restrictive
      end

      # args:
      # position: <Fixnum> (starting at 1, default: add to end)
      def follow_opts args
        add_option args, :main
      end

      def follow_test opts={}, &block
        Card::FollowOption.test[ get_codename(opts) ] = block
      end

      def follower_candidate_ids opts={}, &block
        Card::FollowOption.follower_candidate_ids[ get_codename(opts) ] = block
      end

      private

      def insert_option pos, item, type
        if Card::FollowOption.codenames(type)[pos]
          Card::FollowOption.codenames(type).insert(pos, item)
        else
          # If pos > codenames.size in a previous insert then we have a bunch of preceding nils in the array.
          # Hence, we have to overwrite a nil value if we encounter one and can't use insert.
          Card::FollowOption.codenames(type)[pos] = item
        end
      end

      def add_option opts, type, &block
        codename = get_codename opts
        if opts[:position]
          insert_option opts[:position]-1, codename, type
        else
          Card::FollowOption.codenames(type) << codename
        end
        Card::FollowOption.codenames(:all) << codename
      end

      def get_codename opts
        opts[:codename] || self.name.match(/::(\w+)$/)[1].underscore.to_sym
      end


    end
  end
end