# regenerate parser.rb using `tt parser.treetop`
module Asciidoctor
module Pdf
module FormattedText
grammar Markup
  rule text
    complex
  end

  rule complex
    (cdata / element / entity)* {
      def content
        elements.map {|e| e.content }
      end
    }
  end

  rule element
    # strict tag matching (costs a minor toll)
    # void_element / start_tag complex end_tag &{|seq| seq[0].name == seq[2].name } {

    void_element / start_tag complex end_tag {
      # NOTE content only applies to non-void elements (second part of rule)
      def content
        { type: :element, name: (tag_element = elements[0]).name.to_sym, attributes: tag_element.attributes, pcdata: elements[1].content }
      end
    }
  end

  rule void_element
    '<' void_tag_name attributes (spaces? '/')? '>' {
      def content
        { type: :element, name: elements[1].text_value.to_sym, attributes: elements[2].content }
      end
    }
  end

  rule start_tag
    '<' tag_name attributes '>' {
      def name
        elements[1].text_value
      end

      def attributes
        elements[2].content
      end
    }
  end

  rule tag_name
    # QUESTION faster to do regex?
    # QUESTION can we cut stuff we aren't using? what about supporting hr?
    #'a' / 'b' / 'code' / 'color' / 'del' / 'em' / 'font' / 'i' / 'img' / 'link' / 'span' / 'strikethrough' / 'strong' / 'sub' / 'sup' / 'u'
    'a' / 'code' / 'color' / 'del' / 'em' / 'font' / 'span' / 'strong' / 'sub' / 'sup'
  end

  rule void_tag_name
    'br' / 'img'
  end

  rule attributes
    attribute* {
      def content
        attrs = {}
        elements.each {|e|
          attr_name, attr_val = e.content
          attrs[attr_name.to_sym] = attr_val
        }
        attrs
      end
    }
  end

  rule attribute
    spaces [a-z_]+ '=' '"' [^"]* '"' {
      def content
        [elements[1].text_value, elements[4].text_value]
      end
    }
  end

  rule end_tag
    '</' tag_name '>' {
      def name
        elements[1].text_value
      end
    }
  end

  rule cdata
    [^<&]+ {
      def content
        { type: :text, value: text_value }
      end
    }
  end

  rule entity
    '&' ('#' entity_number / entity_name) ';' {
      def content
        if (entity_value = elements[1]).terminal?
          { type: :entity, name: entity_value.text_value.to_sym }
        else
          { type: :entity, number: entity_value.elements[1].text_value.to_i }
        end
      end
    }
  end

  rule entity_number
    [0-9] 2..4
  end

  rule entity_name
    'amp' / 'apos' / 'gt' / 'lt' / 'quot'
  end

  rule spaces
    ' '+
  end
end
end
end
end