# Be sure to restart your server when you modify this file.
#
# Points are a simple integer value which are given to "meritable" resources
# according to rules in +app/models/merit/point_rules.rb+. They are given on
# actions-triggered, either to the action user or to the method (or array of
# methods) defined in the +:to+ option.
#
# 'score' method may accept a block which evaluates to boolean
# (recieves the object as parameter)

module Merit
  class PointRules
    include Merit::PointRulesMethods

    AVAILABLE_RULES = {
      :comment_author => {
        :action => 'comment#create',
        :undo_action => 'comment#destroy',
        :to => :author,
        :value => 1,
        :default_weight => 10
      },
      :article_author => {
        :action => 'article#create',
        :undo_action => 'article#destroy',
        :to => :author,
        :value => 1,
        :default_weight => 50
      },
      :vote_voteable_author => {
        :action => 'vote#create',
        :undo_action => 'vote#destroy',
        :to => lambda {|vote| vote.voteable.author},
        :profile => lambda {|vote| vote.voteable.profile},
        :value => lambda {|vote| vote.vote},
        :default_weight => 5
      },
      :vote_voteable => {
        :action => 'vote#create',
        :undo_action => 'vote#destroy',
        :to => lambda {|vote| vote.voteable},
        :profile => lambda {|vote| vote.voteable.profile},
        :value => lambda {|vote| vote.vote},
        :default_weight => 5
      },
    }

    # FIXME get value from environment
    def weight(category)
      AVAILABLE_RULES[category][:default_weight]
    end

    def calculate_score(target, category, value)
      value = value.call(target) if value.respond_to?(:call)
      weight(category) * value
    end

    # TODO receive environment parameter
    def initialize
      AVAILABLE_RULES.each do |category, setting|
        [setting[:action], setting[:undo_action]].compact.zip([1, -1]).each do |action, signal|
          score lambda {|target| signal * calculate_score(target, category, setting[:value])}, :on => action, :to => setting[:to], :category => category
        end
      end
    end

  end
end