module Mail

grammar ContentType

  include RFC2822
  include RFC2045

  rule content_type
    main_type "/" sub_type param_hashes:(CFWS ";"* parameter CFWS)* {
      def parameters
        param_hashes.elements.map do |param|
          param.parameter.param_hash
        end
      end
    }
  end

  rule main_type
    discrete_type / composite_type
  end

  # This matches in a case insensitive way:
  #
  #   rule discrete_type
  #     "text" / "image" / "audio" / "video" / "application" / extension_token
  #   end
  rule discrete_type
    [tT] [eE] [xX] [tT] / [iI] [mM] [aA] [gG] [eE] / [aA] [uU] [dD] [iI] [oO] / [vV] [iI] [dD] [eE] [oO] / [aA] [pP] [pP] [lL] [iI] [cC] [aA] [tT] [iI] [oO] [nN] / extension_token
  end

  # This matches in a case insensitive way:
  #
  #   rule composite_type
  #     "message" / "multipart" / extension_token
  #   end
  rule composite_type
    [mM] [eE] [sS] [sS] [aA] [gG] [eE] / [mM] [uU] [lL] [tT] [iI] [pP] [aA] [rR] [tT] / extension_token
  end

  rule extension_token
    ietf_token / custom_x_token
  end

  rule sub_type
    extension_token / iana_token
  end

  rule parameter
    CFWS? attr:attribute "=" val:value CFWS? {
      def param_hash
        {attr.text_value => val.text_value}
      end
    }
  end

  rule attribute
    token+
  end

  rule value
    quoted_string {
      def text_value
        quoted_content.text_value
      end
    } / (token / [\x3d])+
  end

end

end