module Eco
  module Data
    module FuzzyMatch
      class Score < Struct.new(:score, :total)

        def ratio(decimals = 6)
          tot = self.total; sc = self.score
          tot = tot && tot > 0 ? tot : 1
          sc  = sc  && sc  > 0 ? sc  : 0
          (sc.to_f / tot).round(decimals)
        end

        def percent(decimals = 3)
          (100 * ratio).round(decimals)
        end

        def increase(value = 1)
          self.score += value
          raise "Score #{self.score} (increase: #{value}) can't be greater than total #{self.total}" if self.score > self.total
          self.score
        end

        def increase_total(value)
          self.total += value
        end

        def values_at(*keys)
          keys.map do |key|
            self.send(key) if self.respond_to?(key)
          end
        end

        # Merges 2 Score instance objects
        def merge(scr)
          Score.new(*values_at(:score, :total)).merge!(scr)
        end

        def merge!(scr)
          raise "Expecting Score object. Given: #{scr.class}" unless scr.is_a?(Score)
          increase_total(scr.total)
          increase(scr.score)
          self
        end

      end

    end
  end
end