module Rasti
  module Types
    class Float
      class << self

        include Castable

        FORMAT = /^(\d+\.)?\d+$/

        private

        def valid?(value)
          !value.nil? && (valid_string?(value) || transformable?(value))
        end

        def transform(value)
          value.to_f
        end

        def valid_string?(value)
          value.is_a?(::String) && value.match(FORMAT)
        end

        def transformable?(value)
          !value.is_a?(::String) && value.respond_to?(:to_f)
        end

      end
    end
  end
end