1 files changed, 1313 insertions, 0 deletions
diff --git a/trunk/lib/rss/rss.rb b/trunk/lib/rss/rss.rb
new file mode 100644
index 0000000000..4b943ec55b
--- /dev/null
+++ b/trunk/lib/rss/rss.rb
@@ -0,0 +1,1313 @@
+require "time"
+
+class Time
+  class << self
+    unless respond_to?(:w3cdtf)
+      def w3cdtf(date)
+        if /\A\s*
+            (-?\d+)-(\d\d)-(\d\d)
+            (?:T
+            (\d\d):(\d\d)(?::(\d\d))?
+            (\.\d+)?
+            (Z|[+-]\d\d:\d\d)?)?
+            \s*\z/ix =~ date and (($5 and $8) or (!$5 and !$8))
+          datetime = [$1.to_i, $2.to_i, $3.to_i, $4.to_i, $5.to_i, $6.to_i]
+          usec = 0
+          usec = $7.to_f * 1000000 if $7
+          zone = $8
+          if zone
+            off = zone_offset(zone, datetime[0])
+            datetime = apply_offset(*(datetime + [off]))
+            datetime << usec
+            time = Time.utc(*datetime)
+            time.localtime unless zone_utc?(zone)
+            time
+          else
+            datetime << usec
+            Time.local(*datetime)
+          end
+        else
+          raise ArgumentError.new("invalid date: #{date.inspect}")
+        end
+      end
+    end
+  end
+
+  unless method_defined?(:w3cdtf)
+    def w3cdtf
+      if usec.zero?
+        fraction_digits = 0
+      else
+        fraction_digits = Math.log10(usec.to_s.sub(/0*$/, '').to_i).floor + 1
+      end
+      xmlschema(fraction_digits)
+    end
+  end
+end
+
+
+require "English"
+require "rss/utils"
+require "rss/converter"
+require "rss/xml-stylesheet"
+
+module RSS
+
+  VERSION = "0.2.5"
+
+  URI = "http://purl.org/rss/1.0/"
+
+  DEBUG = false
+
+  class Error < StandardError; end
+
+  class OverlappedPrefixError < Error
+    attr_reader :prefix
+    def initialize(prefix)
+      @prefix = prefix
+    end
+  end
+
+  class InvalidRSSError < Error; end
+
+  class MissingTagError < InvalidRSSError
+    attr_reader :tag, :parent
+    def initialize(tag, parent)
+      @tag, @parent = tag, parent
+      super("tag <#{tag}> is missing in tag <#{parent}>")
+    end
+  end
+
+  class TooMuchTagError < InvalidRSSError
+    attr_reader :tag, :parent
+    def initialize(tag, parent)
+      @tag, @parent = tag, parent
+      super("tag <#{tag}> is too much in tag <#{parent}>")
+    end
+  end
+
+  class MissingAttributeError < InvalidRSSError
+    attr_reader :tag, :attribute
+    def initialize(tag, attribute)
+      @tag, @attribute = tag, attribute
+      super("attribute <#{attribute}> is missing in tag <#{tag}>")
+    end
+  end
+
+  class UnknownTagError < InvalidRSSError
+    attr_reader :tag, :uri
+    def initialize(tag, uri)
+      @tag, @uri = tag, uri
+      super("tag <#{tag}> is unknown in namespace specified by uri <#{uri}>")
+    end
+  end
+
+  class NotExpectedTagError < InvalidRSSError
+    attr_reader :tag, :uri, :parent
+    def initialize(tag, uri, parent)
+      @tag, @uri, @parent = tag, uri, parent
+      super("tag <{#{uri}}#{tag}> is not expected in tag <#{parent}>")
+    end
+  end
+  # For backward compatibility :X
+  NotExceptedTagError = NotExpectedTagError
+
+  class NotAvailableValueError < InvalidRSSError
+    attr_reader :tag, :value, :attribute
+    def initialize(tag, value, attribute=nil)
+      @tag, @value, @attribute = tag, value, attribute
+      message = "value <#{value}> of "
+      message << "attribute <#{attribute}> of " if attribute
+      message << "tag <#{tag}> is not available."
+      super(message)
+    end
+  end
+
+  class UnknownConversionMethodError < Error
+    attr_reader :to, :from
+    def initialize(to, from)
+      @to = to
+      @from = from
+      super("can't convert to #{to} from #{from}.")
+    end
+  end
+  # for backward compatibility
+  UnknownConvertMethod = UnknownConversionMethodError
+
+  class ConversionError < Error
+    attr_reader :string, :to, :from
+    def initialize(string, to, from)
+      @string = string
+      @to = to
+      @from = from
+      super("can't convert #{@string} to #{to} from #{from}.")
+    end
+  end
+
+  class NotSetError < Error
+    attr_reader :name, :variables
+    def initialize(name, variables)
+      @name = name
+      @variables = variables
+      super("required variables of #{@name} are not set: #{@variables.join(', ')}")
+    end
+  end
+
+  class UnsupportedMakerVersionError < Error
+    attr_reader :version
+    def initialize(version)
+      @version = version
+      super("Maker doesn't support version: #{@version}")
+    end
+  end
+
+  module BaseModel
+    include Utils
+
+    def install_have_child_element(tag_name, uri, occurs, name=nil, type=nil)
+      name ||= tag_name
+      add_need_initialize_variable(name)
+      install_model(tag_name, uri, occurs, name)
+
+      writer_type, reader_type = type
+      def_corresponded_attr_writer name, writer_type
+      def_corresponded_attr_reader name, reader_type
+      install_element(name) do |n, elem_name|
+        <<-EOC
+        if @#{n}
+          "\#{@#{n}.to_s(need_convert, indent)}"
+        else
+          ''
+        end
+EOC
+      end
+    end
+    alias_method(:install_have_attribute_element, :install_have_child_element)
+
+    def install_have_children_element(tag_name, uri, occurs, name=nil, plural_name=nil)
+      name ||= tag_name
+      plural_name ||= "#{name}s"
+      add_have_children_element(name, plural_name)
+      add_plural_form(name, plural_name)
+      install_model(tag_name, uri, occurs, plural_name, true)
+
+      def_children_accessor(name, plural_name)
+      install_element(name, "s") do |n, elem_name|
+        <<-EOC
+        rv = []
+        @#{n}.each do |x|
+          value = "\#{x.to_s(need_convert, indent)}"
+          rv << value if /\\A\\s*\\z/ !~ value
+        end
+        rv.join("\n")
+EOC
+      end
+    end
+
+    def install_text_element(tag_name, uri, occurs, name=nil, type=nil,
+                             disp_name=nil)
+      name ||= tag_name
+      disp_name ||= name
+      self::ELEMENTS << name unless self::ELEMENTS.include?(name)
+      add_need_initialize_variable(name)
+      install_model(tag_name, uri, occurs, name)
+
+      def_corresponded_attr_writer(name, type, disp_name)
+      def_corresponded_attr_reader(name, type || :convert)
+      install_element(name) do |n, elem_name|
+        <<-EOC
+        if respond_to?(:#{n}_content)
+          content = #{n}_content
+        else
+          content = @#{n}
+        end
+        if content
+          rv = "\#{indent}<#{elem_name}>"
+          value = html_escape(content)
+          if need_convert
+            rv << convert(value)
+          else
+            rv << value
+          end
+    	    rv << "</#{elem_name}>"
+          rv
+        else
+          ''
+        end
+EOC
+      end
+    end
+
+    def install_date_element(tag_name, uri, occurs, name=nil, type=nil, disp_name=nil)
+      name ||= tag_name
+      type ||= :w3cdtf
+      disp_name ||= name
+      self::ELEMENTS << name
+      add_need_initialize_variable(name)
+      install_model(tag_name, uri, occurs, name)
+
+      # accessor
+      convert_attr_reader name
+      date_writer(name, type, disp_name)
+      
+      install_element(name) do |n, elem_name|
+        <<-EOC
+        if @#{n}
+          rv = "\#{indent}<#{elem_name}>"
+          value = html_escape(@#{n}.#{type})
+          if need_convert
+            rv << convert(value)
+          else
+            rv << value
+          end
+    	    rv << "</#{elem_name}>"
+          rv
+        else
+          ''
+        end
+EOC
+      end
+
+    end
+
+    private
+    def install_element(name, postfix="")
+      elem_name = name.sub('_', ':')
+      method_name = "#{name}_element#{postfix}"
+      add_to_element_method(method_name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{method_name}(need_convert=true, indent='')
+        #{yield(name, elem_name)}
+      end
+      private :#{method_name}
+EOC
+    end
+
+    def inherit_convert_attr_reader(*attrs)
+      attrs.each do |attr|
+        attr = attr.id2name if attr.kind_of?(Integer)
+        module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+        def #{attr}_without_inherit
+          convert(@#{attr})
+        end
+
+        def #{attr}
+          if @#{attr}
+            #{attr}_without_inherit
+          elsif @parent
+            @parent.#{attr}
+          else
+            nil
+          end
+        end
+EOC
+      end
+    end
+
+    def uri_convert_attr_reader(*attrs)
+      attrs.each do |attr|
+        attr = attr.id2name if attr.kind_of?(Integer)
+        module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+        def #{attr}_without_base
+          convert(@#{attr})
+        end
+
+        def #{attr}
+          value = #{attr}_without_base
+          return nil if value.nil?
+          if /\\A[a-z][a-z0-9+.\\-]*:/i =~ value
+            value
+          else
+            "\#{base}\#{value}"
+          end
+        end
+EOC
+      end
+    end
+
+    def convert_attr_reader(*attrs)
+      attrs.each do |attr|
+        attr = attr.id2name if attr.kind_of?(Integer)
+        module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+        def #{attr}
+          convert(@#{attr})
+        end
+EOC
+      end
+    end
+
+    def yes_clean_other_attr_reader(*attrs)
+      attrs.each do |attr|
+        attr = attr.id2name if attr.kind_of?(Integer)
+        module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+          attr_reader(:#{attr})
+          def #{attr}?
+            YesCleanOther.parse(@#{attr})
+          end
+        EOC
+      end
+    end
+
+    def yes_other_attr_reader(*attrs)
+      attrs.each do |attr|
+        attr = attr.id2name if attr.kind_of?(Integer)
+        module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+          attr_reader(:#{attr})
+          def #{attr}?
+            Utils::YesOther.parse(@#{attr})
+          end
+        EOC
+      end
+    end
+
+    def csv_attr_reader(*attrs)
+      separator = nil
+      if attrs.last.is_a?(Hash)
+        options = attrs.pop
+        separator = options[:separator]
+      end
+      separator ||= ", "
+      attrs.each do |attr|
+        attr = attr.id2name if attr.kind_of?(Integer)
+        module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+          attr_reader(:#{attr})
+          def #{attr}_content
+            if @#{attr}.nil?
+              @#{attr}
+            else
+              @#{attr}.join(#{separator.dump})
+            end
+          end
+        EOC
+      end
+    end
+
+    def date_writer(name, type, disp_name=name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{name}=(new_value)
+        if new_value.nil?
+          @#{name} = new_value
+        elsif new_value.kind_of?(Time)
+          @#{name} = new_value.dup
+        else
+          if @do_validate
+            begin
+              @#{name} = Time.__send__('#{type}', new_value)
+            rescue ArgumentError
+              raise NotAvailableValueError.new('#{disp_name}', new_value)
+            end
+          else
+            @#{name} = nil
+            if /\\A\\s*\\z/ !~ new_value.to_s
+              begin
+                unless Date._parse(new_value, false).empty?
+                  @#{name} = Time.parse(new_value)
+                end
+              rescue ArgumentError
+              end
+            end
+          end
+        end
+
+        # Is it need?
+        if @#{name}
+          class << @#{name}
+            undef_method(:to_s)
+            alias_method(:to_s, :#{type})
+          end
+        end
+
+      end
+EOC
+    end
+
+    def integer_writer(name, disp_name=name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{name}=(new_value)
+        if new_value.nil?
+          @#{name} = new_value
+        else
+          if @do_validate
+            begin
+              @#{name} = Integer(new_value)
+            rescue ArgumentError
+              raise NotAvailableValueError.new('#{disp_name}', new_value)
+            end
+          else
+            @#{name} = new_value.to_i
+          end
+        end
+      end
+EOC
+    end
+
+    def positive_integer_writer(name, disp_name=name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{name}=(new_value)
+        if new_value.nil?
+          @#{name} = new_value
+        else
+          if @do_validate
+            begin
+              tmp = Integer(new_value)
+              raise ArgumentError if tmp <= 0
+              @#{name} = tmp
+            rescue ArgumentError
+              raise NotAvailableValueError.new('#{disp_name}', new_value)
+            end
+          else
+            @#{name} = new_value.to_i
+          end
+        end
+      end
+EOC
+    end
+
+    def boolean_writer(name, disp_name=name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{name}=(new_value)
+        if new_value.nil?
+          @#{name} = new_value
+        else
+          if @do_validate and
+              ![true, false, "true", "false"].include?(new_value)
+            raise NotAvailableValueError.new('#{disp_name}', new_value)
+          end
+          if [true, false].include?(new_value)
+            @#{name} = new_value
+          else
+            @#{name} = new_value == "true"
+          end
+        end
+      end
+EOC
+    end
+
+    def text_type_writer(name, disp_name=name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{name}=(new_value)
+        if @do_validate and
+            !["text", "html", "xhtml", nil].include?(new_value)
+          raise NotAvailableValueError.new('#{disp_name}', new_value)
+        end
+        @#{name} = new_value
+      end
+EOC
+    end
+
+    def content_writer(name, disp_name=name)
+      klass_name = "self.class::#{Utils.to_class_name(name)}"
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{name}=(new_value)
+        if new_value.is_a?(#{klass_name})
+          @#{name} = new_value
+        else
+          @#{name} = #{klass_name}.new
+          @#{name}.content = new_value
+        end
+      end
+EOC
+    end
+
+    def yes_clean_other_writer(name, disp_name=name)
+      module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+        def #{name}=(value)
+          value = (value ? "yes" : "no") if [true, false].include?(value)
+          @#{name} = value
+        end
+      EOC
+    end
+
+    def yes_other_writer(name, disp_name=name)
+      module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+        def #{name}=(new_value)
+          if [true, false].include?(new_value)
+            new_value = new_value ? "yes" : "no"
+          end
+          @#{name} = new_value
+        end
+      EOC
+    end
+
+    def csv_writer(name, disp_name=name)
+      module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+        def #{name}=(new_value)
+          @#{name} = Utils::CSV.parse(new_value)
+        end
+      EOC
+    end
+
+    def csv_integer_writer(name, disp_name=name)
+      module_eval(<<-EOC, __FILE__, __LINE__ + 1)
+        def #{name}=(new_value)
+          @#{name} = Utils::CSV.parse(new_value) {|v| Integer(v)}
+        end
+      EOC
+    end
+
+    def def_children_accessor(accessor_name, plural_name)
+      module_eval(<<-EOC, *get_file_and_line_from_caller(2))
+      def #{plural_name}
+        @#{accessor_name}
+      end
+
+      def #{accessor_name}(*args)
+        if args.empty?
+          @#{accessor_name}.first
+        else
+          @#{accessor_name}[*args]
+        end
+      end
+
+      def #{accessor_name}=(*args)
+        receiver = self.class.name
+        warn("Warning:\#{caller.first.sub(/:in `.*'\z/, '')}: " \
+             "Don't use `\#{receiver}\##{accessor_name} = XXX'/" \
+             "`\#{receiver}\#set_#{accessor_name}(XXX)'. " \
+             "Those APIs are not sense of Ruby. " \
+             "Use `\#{receiver}\##{plural_name} << XXX' instead of them.")
+        if args.size == 1
+          @#{accessor_name}.push(args[0])
+        else
+          @#{accessor_name}.__send__("[]=", *args)
+        end
+      end
+      alias_method(:set_#{accessor_name}, :#{accessor_name}=)
+EOC
+    end
+  end
+
+  module SetupMaker
+    def setup_maker(maker)
+      target = maker_target(maker)
+      unless target.nil?
+        setup_maker_attributes(target)
+        setup_maker_element(target)
+        setup_maker_elements(target)
+      end
+    end
+
+    private
+    def maker_target(maker)
+      nil
+    end
+
+    def setup_maker_attributes(target)
+    end
+
+    def setup_maker_element(target)
+      self.class.need_initialize_variables.each do |var|
+        value = __send__(var)
+        next if value.nil?
+        if value.respond_to?("setup_maker") and
+            !not_need_to_call_setup_maker_variables.include?(var)
+          value.setup_maker(target)
+        else
+          setter = "#{var}="
+          if target.respond_to?(setter)
+            target.__send__(setter, value)
+          end
+        end
+      end
+    end
+
+    def not_need_to_call_setup_maker_variables
+      []
+    end
+
+    def setup_maker_elements(parent)
+      self.class.have_children_elements.each do |name, plural_name|
+        if parent.respond_to?(plural_name)
+          target = parent.__send__(plural_name)
+          __send__(plural_name).each do |elem|
+            elem.setup_maker(target)
+          end
+        end
+      end
+    end
+  end
+
+  class Element
+    extend BaseModel
+    include Utils
+    extend Utils::InheritedReader
+    include SetupMaker
+
+    INDENT = "  "
+    
+    MUST_CALL_VALIDATORS = {}
+    MODELS = []
+    GET_ATTRIBUTES = []
+    HAVE_CHILDREN_ELEMENTS = []
+    TO_ELEMENT_METHODS = []
+    NEED_INITIALIZE_VARIABLES = []
+    PLURAL_FORMS = {}
+
+    class << self
+      def must_call_validators
+        inherited_hash_reader("MUST_CALL_VALIDATORS")
+      end
+      def models
+        inherited_array_reader("MODELS")
+      end
+      def get_attributes
+        inherited_array_reader("GET_ATTRIBUTES")
+      end
+      def have_children_elements
+        inherited_array_reader("HAVE_CHILDREN_ELEMENTS")
+      end
+      def to_element_methods
+        inherited_array_reader("TO_ELEMENT_METHODS")
+      end
+      def need_initialize_variables
+        inherited_array_reader("NEED_INITIALIZE_VARIABLES")
+      end
+      def plural_forms
+        inherited_hash_reader("PLURAL_FORMS")
+      end
+
+      def inherited_base
+        ::RSS::Element
+      end
+
+      def inherited(klass)
+        klass.const_set("MUST_CALL_VALIDATORS", {})
+        klass.const_set("MODELS", [])
+        klass.const_set("GET_ATTRIBUTES", [])
+        klass.const_set("HAVE_CHILDREN_ELEMENTS", [])
+        klass.const_set("TO_ELEMENT_METHODS", [])
+        klass.const_set("NEED_INITIALIZE_VARIABLES", [])
+        klass.const_set("PLURAL_FORMS", {})
+
+        tag_name = klass.name.split(/::/).last
+        tag_name[0, 1] = tag_name[0, 1].downcase
+        klass.instance_variable_set("@tag_name", tag_name)
+        klass.instance_variable_set("@have_content", false)
+      end
+
+      def install_must_call_validator(prefix, uri)
+        self::MUST_CALL_VALIDATORS[uri] = prefix
+      end
+
+      def install_model(tag, uri, occurs=nil, getter=nil, plural=false)
+        getter ||= tag
+        if m = self::MODELS.find {|t, u, o, g, p| t == tag and u == uri}
+          m[2] = occurs
+        else
+          self::MODELS << [tag, uri, occurs, getter, plural]
+        end
+      end
+
+      def install_get_attribute(name, uri, required=true,
+                                type=nil, disp_name=nil,
+                                element_name=nil)
+        disp_name ||= name
+        element_name ||= name
+        writer_type, reader_type = type
+        def_corresponded_attr_writer name, writer_type, disp_name
+        def_corresponded_attr_reader name, reader_type
+        if type == :boolean and /^is/ =~ name
+          alias_method "#{$POSTMATCH}?", name
+        end
+        self::GET_ATTRIBUTES << [name, uri, required, element_name]
+        add_need_initialize_variable(disp_name)
+      end
+
+      def def_corresponded_attr_writer(name, type=nil, disp_name=nil)
+        disp_name ||= name
+        case type
+        when :integer
+          integer_writer name, disp_name
+        when :positive_integer
+          positive_integer_writer name, disp_name
+        when :boolean
+          boolean_writer name, disp_name
+        when :w3cdtf, :rfc822, :rfc2822
+          date_writer name, type, disp_name
+        when :text_type
+          text_type_writer name, disp_name
+        when :content
+          content_writer name, disp_name
+        when :yes_clean_other
+          yes_clean_other_writer name, disp_name
+        when :yes_other
+          yes_other_writer name, disp_name
+        when :csv
+          csv_writer name
+        when :csv_integer
+          csv_integer_writer name
+        else
+          attr_writer name
+        end
+      end
+
+      def def_corresponded_attr_reader(name, type=nil)
+        case type
+        when :inherit
+          inherit_convert_attr_reader name
+        when :uri
+          uri_convert_attr_reader name
+        when :yes_clean_other
+          yes_clean_other_attr_reader name
+        when :yes_other
+          yes_other_attr_reader name
+        when :csv
+          csv_attr_reader name
+        when :csv_integer
+          csv_attr_reader name, :separator => ","
+        else
+          convert_attr_reader name
+        end
+      end
+
+      def content_setup(type=nil, disp_name=nil)
+        writer_type, reader_type = type
+        def_corresponded_attr_writer :content, writer_type, disp_name
+        def_corresponded_attr_reader :content, reader_type
+        @have_content = true
+      end
+
+      def have_content?
+        @have_content
+      end
+
+      def add_have_children_element(variable_name, plural_name)
+        self::HAVE_CHILDREN_ELEMENTS << [variable_name, plural_name]
+      end
+
+      def add_to_element_method(method_name)
+        self::TO_ELEMENT_METHODS << method_name
+      end
+
+      def add_need_initialize_variable(variable_name)
+        self::NEED_INITIALIZE_VARIABLES << variable_name
+      end
+
+      def add_plural_form(singular, plural)
+        self::PLURAL_FORMS[singular] = plural
+      end
+
+      def required_prefix
+        nil
+      end
+
+      def required_uri
+        ""
+      end
+
+      def need_parent?
+        false
+      end
+
+      def install_ns(prefix, uri)
+        if self::NSPOOL.has_key?(prefix)
+          raise OverlappedPrefixError.new(prefix)
+        end
+        self::NSPOOL[prefix] = uri
+      end
+
+      def tag_name
+        @tag_name
+      end
+    end
+
+    attr_accessor :parent, :do_validate
+
+    def initialize(do_validate=true, attrs=nil)
+      @parent = nil
+      @converter = nil
+      if attrs.nil? and (do_validate.is_a?(Hash) or do_validate.is_a?(Array))
+        do_validate, attrs = true, do_validate
+      end
+      @do_validate = do_validate
+      initialize_variables(attrs || {})
+    end
+
+    def tag_name
+      self.class.tag_name
+    end
+
+    def full_name
+      tag_name
+    end
+    
+    def converter=(converter)
+      @converter = converter
+      targets = children.dup
+      self.class.have_children_elements.each do |variable_name, plural_name|
+        targets.concat(__send__(plural_name))
+      end
+      targets.each do |target|
+        target.converter = converter unless target.nil?
+      end
+    end
+
+    def convert(value)
+      if @converter
+        @converter.convert(value)
+      else
+        value
+      end
+    end
+
+    def valid?(ignore_unknown_element=true)
+      validate(ignore_unknown_element)
+      true
+    rescue RSS::Error
+      false
+    end
+
+    def validate(ignore_unknown_element=true)
+      do_validate = @do_validate
+      @do_validate = true
+      validate_attribute
+      __validate(ignore_unknown_element)
+    ensure
+      @do_validate = do_validate
+    end
+    
+    def validate_for_stream(tags, ignore_unknown_element=true)
+      validate_attribute
+      __validate(ignore_unknown_element, tags, false)
+    end
+
+    def to_s(need_convert=true, indent='')
+      if self.class.have_content?
+        return "" if !empty_content? and !content_is_set?
+        rv = tag(indent) do |next_indent|
+          if empty_content?
+            ""
+          else
+            xmled_content
+          end
+        end
+      else
+        rv = tag(indent) do |next_indent|
+          self.class.to_element_methods.collect do |method_name|
+            __send__(method_name, false, next_indent)
+          end
+        end
+      end
+      rv = convert(rv) if need_convert
+      rv
+    end
+
+    def have_xml_content?
+      false
+    end
+
+    def need_base64_encode?
+      false
+    end
+
+    def set_next_element(tag_name, next_element)
+      klass = next_element.class
+      prefix = ""
+      prefix << "#{klass.required_prefix}_" if klass.required_prefix
+      key = "#{prefix}#{tag_name.gsub(/-/, '_')}"
+      if self.class.plural_forms.has_key?(key)
+        ary = __send__("#{self.class.plural_forms[key]}")
+        ary << next_element
+      else
+        __send__("#{key}=", next_element)
+      end
+    end
+
+    protected
+    def have_required_elements?
+      self.class::MODELS.all? do |tag, uri, occurs, getter|
+        if occurs.nil? or occurs == "+"
+          child = __send__(getter)
+          if child.is_a?(Array)
+            children = child
+            children.any? {|c| c.have_required_elements?}
+          else
+            !child.to_s.empty?
+          end
+        else
+          true
+        end
+      end
+    end
+
+    private
+    def initialize_variables(attrs)
+      normalized_attrs = {}
+      attrs.each do |key, value|
+        normalized_attrs[key.to_s] = value
+      end
+      self.class.need_initialize_variables.each do |variable_name|
+        value = normalized_attrs[variable_name.to_s]
+        if value
+          __send__("#{variable_name}=", value)
+        else
+          instance_variable_set("@#{variable_name}", nil)
+        end
+      end
+      initialize_have_children_elements
+      @content = normalized_attrs["content"] if self.class.have_content?
+    end
+
+    def initialize_have_children_elements
+      self.class.have_children_elements.each do |variable_name, plural_name|
+        instance_variable_set("@#{variable_name}", [])
+      end
+    end
+
+    def tag(indent, additional_attrs={}, &block)
+      next_indent = indent + INDENT
+
+      attrs = collect_attrs
+      return "" if attrs.nil?
+
+      return "" unless have_required_elements?
+
+      attrs.update(additional_attrs)
+      start_tag = make_start_tag(indent, next_indent, attrs.dup)
+
+      if block
+        content = block.call(next_indent)
+      else
+        content = []
+      end
+
+      if content.is_a?(String)
+        content = [content]
+        start_tag << ">"
+        end_tag = "</#{full_name}>"
+      else
+        content = content.reject{|x| x.empty?}
+        if content.empty?
+          return "" if attrs.empty?
+          end_tag = "/>"
+        else
+          start_tag << ">\n"
+          end_tag = "\n#{indent}</#{full_name}>"
+        end
+      end
+      
+      start_tag + content.join("\n") + end_tag
+    end
+
+    def make_start_tag(indent, next_indent, attrs)
+      start_tag = ["#{indent}<#{full_name}"]
+      unless attrs.empty?
+        start_tag << attrs.collect do |key, value|
+          %Q[#{h key}="#{h value}"]
+        end.join("\n#{next_indent}")
+      end
+      start_tag.join(" ")
+    end
+
+    def collect_attrs
+      attrs = {}
+      _attrs.each do |name, required, alias_name|
+        value = __send__(alias_name || name)
+        return nil if required and value.nil?
+        next if value.nil?
+        return nil if attrs.has_key?(name)
+        attrs[name] = value
+      end
+      attrs
+    end
+    
+    def tag_name_with_prefix(prefix)
+      "#{prefix}:#{tag_name}"
+    end
+
+    # For backward compatibility
+    def calc_indent
+      ''
+    end
+
+    def children
+      rv = []
+      self.class.models.each do |name, uri, occurs, getter|
+        value = __send__(getter)
+        next if value.nil?
+        value = [value] unless value.is_a?(Array)
+        value.each do |v|
+          rv << v if v.is_a?(Element)
+        end
+      end
+      rv
+    end
+
+    def _tags
+      rv = []
+      self.class.models.each do |name, uri, occurs, getter, plural|
+        value = __send__(getter)
+        next if value.nil?
+        if plural and value.is_a?(Array)
+          rv.concat([[uri, name]] * value.size)
+        else
+          rv << [uri, name]
+        end
+      end
+      rv
+    end
+
+    def _attrs
+      self.class.get_attributes.collect do |name, uri, required, element_name|
+        [element_name, required, name]
+      end
+    end
+
+    def __validate(ignore_unknown_element, tags=_tags, recursive=true)
+      if recursive
+        children.compact.each do |child|
+          child.validate
+        end
+      end
+      must_call_validators = self.class.must_call_validators
+      tags = tag_filter(tags.dup)
+      p tags if DEBUG
+      must_call_validators.each do |uri, prefix|
+        _validate(ignore_unknown_element, tags[uri], uri)
+        meth = "#{prefix}_validate"
+        if !prefix.empty? and respond_to?(meth, true)
+          __send__(meth, ignore_unknown_element, tags[uri], uri)
+        end
+      end
+    end
+
+    def validate_attribute
+      _attrs.each do |a_name, required, alias_name|
+        value = instance_variable_get("@#{alias_name || a_name}")
+        if required and value.nil?
+          raise MissingAttributeError.new(tag_name, a_name)
+        end
+        __send__("#{alias_name || a_name}=", value)
+      end
+    end
+
+    def _validate(ignore_unknown_element, tags, uri, models=self.class.models)
+      count = 1
+      do_redo = false
+      not_shift = false
+      tag = nil
+      models = models.find_all {|model| model[1] == uri}
+      element_names = models.collect {|model| model[0]}
+      if tags
+        tags_size = tags.size
+        tags = tags.sort_by {|x| element_names.index(x) || tags_size}
+      end
+
+      _tags = tags.dup if tags
+      models.each_with_index do |model, i|
+        name, model_uri, occurs, getter = model
+
+        if DEBUG
+          p "before"
+          p tags
+          p model
+        end
+
+        if not_shift
+          not_shift = false
+        elsif tags
+          tag = tags.shift
+        end
+
+        if DEBUG
+          p "mid"
+          p count
+        end
+
+        case occurs
+        when '?'
+          if count > 2
+            raise TooMuchTagError.new(name, tag_name)
+          else
+            if name == tag
+              do_redo = true
+            else
+              not_shift = true
+            end
+          end
+        when '*'
+          if name == tag
+            do_redo = true
+          else
+            not_shift = true
+          end
+        when '+'
+          if name == tag
+            do_redo = true
+          else
+            if count > 1
+              not_shift = true
+            else
+              raise MissingTagError.new(name, tag_name)
+            end
+          end
+        else
+          if name == tag
+            if models[i+1] and models[i+1][0] != name and
+                tags and tags.first == name
+              raise TooMuchTagError.new(name, tag_name)
+            end
+          else
+            raise MissingTagError.new(name, tag_name)
+          end
+        end
+
+        if DEBUG
+          p "after"
+          p not_shift
+          p do_redo
+          p tag
+        end
+
+        if do_redo
+          do_redo = false
+          count += 1
+          redo
+        else
+          count = 1
+        end
+
+      end
+
+      if !ignore_unknown_element and !tags.nil? and !tags.empty?
+        raise NotExpectedTagError.new(tags.first, uri, tag_name)
+      end
+
+    end
+
+    def tag_filter(tags)
+      rv = {}
+      tags.each do |tag|
+        rv[tag[0]] = [] unless rv.has_key?(tag[0])
+        rv[tag[0]].push(tag[1])
+      end
+      rv
+    end
+
+    def empty_content?
+      false
+    end
+
+    def content_is_set?
+      if have_xml_content?
+        __send__(self.class.xml_getter)
+      else
+        content
+      end
+    end
+
+    def xmled_content
+      if have_xml_content?
+        __send__(self.class.xml_getter).to_s
+      else
+        _content = content
+        _content = [_content].pack("m").delete("\n") if need_base64_encode?
+        h(_content)
+      end
+    end
+  end
+
+  module RootElementMixin
+
+    include XMLStyleSheetMixin
+    
+    attr_reader :output_encoding
+    attr_reader :feed_type, :feed_subtype, :feed_version
+    attr_accessor :version, :encoding, :standalone
+    def initialize(feed_version, version=nil, encoding=nil, standalone=nil)
+      super()
+      @feed_type = nil
+      @feed_subtype = nil
+      @feed_version = feed_version
+      @version = version || '1.0'
+      @encoding = encoding
+      @standalone = standalone
+      @output_encoding = nil
+    end
+
+    def feed_info
+      [@feed_type, @feed_version, @feed_subtype]
+    end
+
+    def output_encoding=(enc)
+      @output_encoding = enc
+      self.converter = Converter.new(@output_encoding, @encoding)
+    end
+
+    def setup_maker(maker)
+      maker.version = version
+      maker.encoding = encoding
+      maker.standalone = standalone
+
+      xml_stylesheets.each do |xss|
+        xss.setup_maker(maker)
+      end
+
+      super
+    end
+
+    def to_feed(type, &block)
+      Maker.make(type) do |maker|
+        setup_maker(maker)
+        block.call(maker) if block
+      end
+    end
+
+    def to_rss(type, &block)
+      to_feed("rss#{type}", &block)
+    end
+
+    def to_atom(type, &block)
+      to_feed("atom:#{type}", &block)
+    end
+
+    def to_xml(type=nil, &block)
+      if type.nil? or same_feed_type?(type)
+        to_s
+      else
+        to_feed(type, &block).to_s
+      end
+    end
+
+    private
+    def same_feed_type?(type)
+      if /^(atom|rss)?(\d+\.\d+)?(?::(.+))?$/i =~ type
+        feed_type = ($1 || @feed_type).downcase
+        feed_version = $2 || @feed_version
+        feed_subtype = $3 || @feed_subtype
+        [feed_type, feed_version, feed_subtype] == feed_info
+      else
+        false
+      end
+    end
+
+    def tag(indent, attrs={}, &block)
+      rv = super(indent, ns_declarations.merge(attrs), &block)
+      return rv if rv.empty?
+      "#{xmldecl}#{xml_stylesheet_pi}#{rv}"
+    end
+
+    def xmldecl
+      rv = %Q[<?xml version="#{@version}"]
+      if @output_encoding or @encoding
+        rv << %Q[ encoding="#{@output_encoding or @encoding}"]
+      end
+      rv << %Q[ standalone="yes"] if @standalone
+      rv << "?>\n"
+      rv
+    end
+    
+    def ns_declarations
+      decls = {}
+      self.class::NSPOOL.collect do |prefix, uri|
+        prefix = ":#{prefix}" unless prefix.empty?
+        decls["xmlns#{prefix}"] = uri
+      end
+      decls
+    end
+
+    def maker_target(target)
+      target
+    end
+  end
+end