module Yema
  class Rule
    class StrongType < self

      attr_reader :type, :strict, :member_type

      def initialize(attribute_name, options={})
        super
        extract_options(options)
      end

      def self.required_options
        [:type]
      end

      def matches?(value)
        return allow_nil_rule(value) if strict == :allow_nil
        if type == TrueClass || type == FalseClass
          boolean_matches?(value)
        elsif value.kind_of?(Array)
          array_matches?(value)
        else
          value.kind_of?(type)
        end
      end

      private

      def allow_nil_rule(value)
        return true if value.nil?
        value.kind_of?(type)
      end

      def extract_options(options)
        @type        = options.fetch(:type)
        @member_type = options.fetch(:member_type, nil)
        @strict      = options.fetch(:strict, :high)
        assert_options_value
      end

      def assert_options_value
        raise InvalidOptionError, "Strict option only accept [:high, :allow_nil]" unless [:high, :allow_nil].include?(strict)
      end

      def boolean_matches?(value)
        value.equal?(true) || value.equal?(false)
      end

      def array_matches?(value)
        if member_type
          value.kind_of?(Array) && value.all? { |v| v.kind_of?(member_type) }
        else
          value.kind_of?(Array)
        end
      end
    end
  end
end