Refactoring in response to Aldric

module SgfParser
  class Tree

    private

    def parse
      while char = next_character
        case char
        when '('   then store_branch
        when ')'   then fetch_branch
        when ';'   then advance_node
        when '['   then get_and_store_property
        else       store_character(char)
        end
      end
    end

    def current_node
      @current_node ||= @root
    end

    def content
      @content ||= {}
    end

    def identity
      @identify ||= ""
    end

    def advance_node
      parent = current_node
      @current_node = Node.new :parent => parent
      parent.add_properties content
      parent.add_children @current_node
      clear_temporary_data
    end

    def store_branch
      @branches ||= []
      @branches.unshift @current_node
    end

    def fetch_branch
      @current_node = @branches.shift
      clear_temporary_data
    end

    def get_and_store_property
      @content[@identity] ||= ""
      @content[@identity] << get_property
      @identity = ""
    end

    def get_property
      buffer = ""
      while true
        parsed_bit = @stream.sysread(1)
        break if parsed_bit == "]"
        parsed_bit << @stream.sysread(1) if parsed_bit == "\\"
        parsed_bit = "]" if parsed_bit == "\\]"
        buffer << parsed_bit
      end
      buffer
    end

    def clear_temporary_data
      @content.clear
      @identity = ""
    end

    def clean_string
      @sgf.gsub! "\\\\n\\\\r", ""
      @sgf.gsub! "\\\\r\\\\n", ""
      @sgf.gsub! "\\\\r", ""
      @sgf.gsub! "\\\\n", ""
      #@sgf.gsub! "\n", ""
      @sgf
    end

    def character_available?
      @stream ||= StringIO.new(clean_string, 'r')
      !@stream.eof?
    end

    def next_character
      character_available? && @stream.sysread(1)
    end

    def store_character(char)
      @identity << char unless char == "\n"
    end
  end
end